TREK/client/src/pages/tripPlanner/useTripPlanner.ts

import { useLoadRoadtripSettings, useRoadtripSettings } from '../../hooks/useRoadtripSettings'
import { roadtripPreferencesRepo } from '../../repo/roadtripPreferencesRepo'
import { publishRoadtripPreferences } from '../../store/roadtripPreferencesStore'
import { useState, useEffect, useCallback, useMemo, useRef } from 'react'
import { useParams, useNavigate, useSearchParams } from 'react-router'
import { useTripStore } from '../../store/tripStore'
import { useCanDo } from '../../store/permissionsStore'
import { useSettingsStore } from '../../store/settingsStore'
import { dayColor } from '../../components/Roadtrip/dayColors'
import { getCached, fetchPhoto } from '../../services/photoService'
import { useToast } from '../../components/shared/Toast'
import { Map, Ticket, PackageCheck, Wallet, FolderOpen, Users, Train, Route } from 'lucide-react'
import { resolvePluginIcon } from '../../components/shared/PluginIcon'
import { useTranslation, translateApiError } from '../../i18n'
import { addonsApi, accommodationsApi, authApi, tripsApi, assignmentsApi, healthApi, airtrailApi, mapsApi, placesApi } from '../../api/client'
import { getDayOrder } from '../../utils/dayOrder'
import { TRANSPORT_TYPES, timedSlot } from '../../utils/dayMerge'
import { isOvernightCategory } from '../../components/Roadtrip/stopKinds'
import { parsedItemToDraft, isTransportItem, isUnplaceableItem, type BookingReviewDraft } from '../../components/Planner/parsedItemToDraft'
import type { BookingImportPreviewItem } from '@trek/shared'
import { accommodationRepo } from '../../repo/accommodationRepo'
import { offlineDb, getImportFiles, deleteImportFiles } from '../../db/offlineDb'
import { isEffectivelyOffline } from '../../sync/networkMode'
import { useBackgroundTasksStore } from '../../store/backgroundTasksStore'
import { useAuthStore } from '../../store/authStore'
import { useResizablePanels } from '../../hooks/useResizablePanels'
import { useTripWebSocket } from '../../hooks/useTripWebSocket'
import { useRouteCalculation } from '../../hooks/useRouteCalculation'
import { useRoadtripRoutes, type RoadtripStop } from '../../components/Roadtrip/useRoadtripRoutes'
import { useAutomaticDayPoints } from '../../components/Roadtrip/useAutomaticDayPoints'
import { useDayBoundaries } from '../../components/Roadtrip/useDayBoundaries'
import type { DayBoundaryControls } from '../../components/Map/dayBoundaryDrag'
import { dayWindow, roadtripInsertion } from '../../components/Roadtrip/dayWindow'
import { carrierReservationIds, isStoredStop, viasLeaving, type CarrierTerminal } from '@trek/shared/roadtrip'
import { useTripRouteOverview } from '../../components/Map/useTripRouteOverview'
import { useDawarichTrail } from '../../components/Map/useDawarichTrail'
import { collapsedDayDates } from '../../components/Map/dawarichTrail'
import { useRoadtripCorridor } from '../../components/Roadtrip/useRoadtripCorridor'
import { PHONE_CORRIDOR_OPTIONS } from '../../components/Roadtrip/corridorSearchModel'
import { useRoadtripVias } from '../../components/Roadtrip/useRoadtripVias'
import { useRefuelSearch } from '../../components/Roadtrip/useRefuelSearch'
import type { RefuelCandidate } from '../../components/Roadtrip/refuelSuggestion'
import { useFollowTrack } from '../../components/Roadtrip/useFollowTrack'
import { openOn, useRouteAlternatives, type RailDrive } from '../../components/Roadtrip/useRouteAlternatives'
import { alternativesBusy, buildAlternativeOverlays } from '../../components/Roadtrip/alternativeOverlays'
import { pinAlternative, railDriveOn, railLegAt, refusalHint, type PinProof } from '../../components/Roadtrip/alternativePins'
import { stopArrival } from '../../components/Roadtrip/stopArrival'
import type { CorridorPoi } from '../../components/Roadtrip/useCorridorPois'
import { projectOntoRoute, sliceAtMeters, type CorridorHit, type LatLng } from '../../components/Roadtrip/corridor'
import {
  insertIndexForAlong,
  reanchorAfterInsert,
  reanchorAfterRemove,
  reanchorByStopOrder,
  isServiceStopType, refuelStopTypeFor, reanchorAfterReorder, type DryPoint } from '../../components/Roadtrip/roadtripModel'
import type { ManualStopTarget, ServiceStopMode } from '../../components/Roadtrip/manualStop'
import type { RoadtripStopDraft } from '../../components/Roadtrip/RoadtripStopPopup'
import type { StayDraft } from '../../components/Roadtrip/RoadtripStayModal'
import { inspectorStay } from '../../components/Roadtrip/stayReading'
import { MAX_TRIP_DAYS, type RoadtripStopType } from '@trek/shared'
import { usePlaceSelection } from '../../hooks/usePlaceSelection'
import { usePlannerHistory } from '../../hooks/usePlannerHistory'
import { useAirtrailConnection } from '../../hooks/useAirtrailConnection'
import { useIsTouch } from '../../hooks/useIsTouch'
import { usePluginStore } from '../../store/pluginStore'
import type { Accommodation, Assignment, TripMember, Day, Place, Reservation } from '../../types'
import { OFM_POSITRON, DEFAULT_MAP_LAT, DEFAULT_MAP_LNG, DEFAULT_MAP_ZOOM } from '../../constants/mapDefaults'
import { useTileUrl } from '../../hooks/useTileUrl'
import { applyStayStops } from '../../store/stayStops'
import { resolvePoolAssignmentId } from './tripPlannerModel'
import { isDeepLinkableTripTab, TRIP_TAB_LABEL_KEYS } from '../../constants/tripTabs'
import { isRoutableReservation } from '../../utils/reservationRoutes'
import {
  parseStoredConnections, resolveEffectiveConnections, resolveVisibleConnectionIds,
  toggleConnectionId, toggleAllConnections as flipAllConnectionsMode,
  type StoredConnections,
} from '../../utils/connectionsVisibility'
import { plannedPlaceIds, plannedPlaceIdsForDay } from '../../utils/plannedPlaces'

/** Stable empty list so the road trip hook stays inert while its mode is off. */
const EMPTY_DAYS: Day[] = []
const EMPTY_RESERVATIONS: Reservation[] = []

/**
 * Trip planner page logic — the big one. Owns the trip store wiring, addon
 * gating, accommodations/members loading, the tab + resizable-panel + selection
 * state, every place/assignment/reservation/transport CRUD handler (with undo),
 * the map filters/derivations and the splash gate. TripPlannerPage stays a
 * wiring container that lays out the day/map/places panes and modals.
 * Behaviour is identical to the previous in-component logic.
 */
export function useTripPlanner() {
  const { id } = useParams<{ id: string }>()
  // The route param is a string; convert once here so every downstream component
  // prop and store call gets a real number. An absent/invalid id becomes NaN,
  // which stays falsy in the `if (tripId)` guards below.
  const tripId = id ? Number(id) : Number.NaN
  const navigate = useNavigate()
  const toast = useToast()
  const { t, language, locale } = useTranslation()
  const { settings } = useSettingsStore()
  const roadtripSettings = useRoadtripSettings(s => s, tripId)
  // trip-page plugins mount as tabs inside this trip planner (tripId-scoped).
  const allPlugins = usePluginStore(s => s.plugins)
  const pluginsLoaded = usePluginStore(s => s.loaded)
  const placesPhotosEnabled = useAuthStore(s => s.placesPhotosEnabled)
  const trip = useTripStore(s => s.trip)
  const days = useTripStore(s => s.days)
  const allPlaces = useTripStore(s => s.places)
  const storedAssignments = useTripStore(s => s.assignments)
  const packingItems = useTripStore(s => s.packingItems)
  const todoItems = useTripStore(s => s.todoItems)
  const categories = useTripStore(s => s.categories)
  const reservations = useTripStore(s => s.reservations)
  const budgetItems = useTripStore(s => s.budgetItems)
  const files = useTripStore(s => s.files)
  const selectedDayId = useTripStore(s => s.selectedDayId)
  const isLoading = useTripStore(s => s.isLoading)
  // Actions — stable references, don't cause re-renders
  const tripActions = useRef(useTripStore.getState()).current
  const can = useCanDo()
  const canUploadFiles = can('file_upload', trip)
  const { pushUndo, undo, canUndo, lastActionLabel } = usePlannerHistory()

  const handleUndo = useCallback(async () => {
    const label = lastActionLabel
    await undo()
    toast.info(t('undo.done', { action: label ?? '' }))
  }, [undo, lastActionLabel, toast])

  const [enabledAddons, setEnabledAddons] = useState<Record<string, boolean>>({ packing: true, budget: true, documents: true, collab: false, roadtrip: false, dawarich: false })
  // The values above are an optimistic guess until the addon feed answers. The
  // tab guard below waits for this before evicting anything, so a tab we were
  // asked to open ('collab' in particular, guessed off) survives the gap.
  const [addonsLoaded, setAddonsLoaded] = useState<boolean>(false)
  // Road trip mode swaps the plan view's left rail (and later its map layer) for the
  // drive-first reading of the same trip. Per trip and per session, like the tab choice:
  // someone planning a road trip stays in it across reloads without it leaking into
  // their next, non-driving trip.
  const [storedRoadtripMode, setRoadtripMode] = useState<boolean>(() => sessionStorage.getItem(`trip-roadtrip-${tripId}`) === '1')
  // Declared here rather than with the other layout state further down, because
  // road-trip mode is decided on it and the assignment and place lists below are
  // decided on that. One subscriber for the whole hook.
  const [isMobile, setIsMobile] = useState(() => window.innerWidth < 768)
  useEffect(() => {
    const mq = window.matchMedia('(max-width: 767px)')
    const handler = (e: MediaQueryListEvent) => setIsMobile(e.matches)
    mq.addEventListener('change', handler)
    return () => mq.removeEventListener('change', handler)
  }, [])
  // The phone shell has no road-trip surface at all: no rail, no drive lines, and
  // no switch to turn the mode back off. Narrowing a desktop window past the
  // phone breakpoint used to carry the flag across anyway, which took the trip
  // overview pill away with nothing in its place and listed every booked night
  // twice. The flag is kept, so widening the window again returns to the drive.
  const roadtripMode = storedRoadtripMode && !isMobile
  // Two reasons a stop can be road-trip-only, and they are not the same reason.
  //
  // The switch is the traveller's: it hides the petrol stations and rest areas
  // they added along the drive from a day list they want to read as a plan.
  //
  // A stop a lodging booking put there is hidden whatever the switch says,
  // because the day already shows that booking as its own overnight block and
  // the row would be the same hotel a second time. Road trip mode wants it: the
  // drive has to end somewhere, and that somewhere is where you sleep.
  const assignments = useMemo(() => {
    if (roadtripMode) return storedAssignments
    const hideServiceStops = roadtripSettings.roadtrip_service_stops_in_days === false
    const hidden = (visit: Assignment) => visit.accommodation_id != null
      || (hideServiceStops && isServiceStopType(visit.place?.stop_type))
    // Same object back when nothing is hidden, so a trip without bookings does not
    // rebuild every day list on each render of this hook.
    if (!Object.values(storedAssignments).some(visits => visits.some(hidden))) return storedAssignments
    return Object.fromEntries(
      Object.entries(storedAssignments).map(([dayId, visits]) => [dayId, visits.filter(v => !hidden(v))]),
    )
  }, [roadtripMode, roadtripSettings.roadtrip_service_stops_in_days, storedAssignments])
  const places = useMemo(() => roadtripMode || roadtripSettings.roadtrip_service_stops_in_days !== false ? allPlaces : allPlaces.filter(place => !isServiceStopType(place.stop_type)), [roadtripMode, roadtripSettings.roadtrip_service_stops_in_days, allPlaces])
  const toggleRoadtripMode = useCallback(() => {
    setRoadtripMode(prev => {
      const next = !prev
      sessionStorage.setItem(`trip-roadtrip-${tripId}`, next ? '1' : '0')
      return next
    })
  }, [tripId])
  const [collabFeatures, setCollabFeatures] = useState<{ chat: boolean; notes: boolean; links: boolean; polls: boolean; whatsnext: boolean }>({ chat: true, notes: true, links: true, polls: true, whatsnext: true })
  const [tripAccommodations, setTripAccommodations] = useState<Accommodation[]>([])
  const [allowedFileTypes, setAllowedFileTypes] = useState<string | null>(null)
  const [tripMembers, setTripMembers] = useState<TripMember[]>([])

  // Re-fetch the trip roster so consumers (Costs participants, Collab, …) pick up a
  // just-added guest or member without a full page reload.
  const refreshMembers = useCallback(() => {
    if (!tripId || isEffectivelyOffline()) return
    tripsApi.getMembers(tripId).then(d => {
      const all = [d.owner, ...(d.members || [])].filter(Boolean)
      setTripMembers(all)
    }).catch(() => {})
  }, [tripId])

  const loadAccommodations = useCallback(() => {
    if (tripId) {
      accommodationRepo.list(tripId).then(d => setTripAccommodations(d.accommodations || [])).catch(() => {})
      tripActions.loadReservations(tripId)
    }
  }, [tripId])

  useEffect(() => {
    addonsApi.enabled().then(data => {
      const map: Record<string, boolean> = {}
      data.addons.forEach(a => { map[a.id] = true })
      setEnabledAddons({ packing: !!map.packing, budget: !!map.budget, documents: !!map.documents, collab: !!map.collab, roadtrip: !!map.roadtrip, dawarich: !!map.dawarich })
      if (data.collabFeatures) setCollabFeatures(data.collabFeatures)
    }).catch(() => {}).finally(() => setAddonsLoaded(true))
    authApi.getAppConfig().then(config => {
      if (config.allowed_file_types) setAllowedFileTypes(config.allowed_file_types)
    }).catch(() => {})
  }, [])


  const tripPagePlugins = allPlugins.filter(p => p.type === 'trip-page')
  const tripPluginIds = tripPagePlugins.map(p => p.id).join(',')

  // A trip-page plugin may replace core tabs while it's active (its manifest names
  // them; 'plan' is never replaceable) and may pick where its own tab sits.
  const replacedTabs = new Set(tripPagePlugins.flatMap(p => p.tripPage?.replaces ?? []))
  const TRIP_TABS = [
    { id: 'plan', label: t(TRIP_TAB_LABEL_KEYS.plan), icon: Map },
    { id: 'transports', label: t(TRIP_TAB_LABEL_KEYS.transports), icon: Train },
    { id: 'buchungen', label: t(TRIP_TAB_LABEL_KEYS.buchungen), shortLabel: t('trip.tabs.reservationsShort'), icon: Ticket },
    // Phone only: the desktop reaches the drive through the mode switch beside the
    // day plan, and a second entry point there would be a tab nobody needs.
    ...(enabledAddons.roadtrip && isMobile ? [{ id: 'roadtrip', label: t(TRIP_TAB_LABEL_KEYS.roadtrip), icon: Route }] : []),
    ...(enabledAddons.packing ? [{ id: 'listen', label: t(TRIP_TAB_LABEL_KEYS.listen), shortLabel: t('trip.tabs.listsShort'), icon: PackageCheck }] : []),
    ...(enabledAddons.budget ? [{ id: 'finanzplan', label: t(TRIP_TAB_LABEL_KEYS.finanzplan), icon: Wallet }] : []),
    ...(enabledAddons.documents ? [{ id: 'dateien', label: t(TRIP_TAB_LABEL_KEYS.dateien), icon: FolderOpen }] : []),
    ...(enabledAddons.collab ? [{ id: 'collab', label: t(TRIP_TAB_LABEL_KEYS.collab), icon: Users }] : []),
  ].filter(tab => tab.id === 'plan' || !replacedTabs.has(tab.id))
  // Positioned plugin tabs splice in ascending order so two positions stay stable;
  // the rest append, exactly as before this capability existed.
  const positioned = tripPagePlugins.filter(p => p.tripPage?.position != null).sort((a, b) => (a.tripPage!.position! - b.tripPage!.position!))
  for (const p of positioned) TRIP_TABS.splice(Math.min(p.tripPage!.position!, TRIP_TABS.length), 0, { id: `plugin:${p.id}`, label: p.name, icon: resolvePluginIcon(p.icon) })
  for (const p of tripPagePlugins.filter(p => p.tripPage?.position == null)) TRIP_TABS.push({ id: `plugin:${p.id}`, label: p.name, icon: resolvePluginIcon(p.icon) })

  const [searchParams, setSearchParams] = useSearchParams()

  // ?tab=<id> opens the trip straight on that tab (the startup destination
  // setting, a browser shortcut, a wrapper app). It beats the session's last
  // tab because it is an explicit request for this one, and it is read in the
  // initializer rather than an effect so the planner never paints the plan view
  // first and swaps a frame later.
  const [activeTab, setActiveTab] = useState<string>(() => {
    const requested = searchParams.get('tab')
    if (requested && isDeepLinkableTripTab(requested)) return requested
    return sessionStorage.getItem(`trip-tab-${tripId}`) || 'plan'
  })

  useEffect(() => {
    // Don't evict a saved plugin tab before the plugin feed has loaded.
    if (activeTab.startsWith('plugin:') && !pluginsLoaded) return
    // Same for the addon-owned tabs: until the feed answers, enabledAddons is a
    // guess, and evicting on a guess would drop a legitimately requested tab.
    if (!addonsLoaded) return
    const validTabIds = TRIP_TABS.map(t => t.id)
    if (!validTabIds.includes(activeTab)) {
      setActiveTab('plan')
      sessionStorage.setItem(`trip-tab-${tripId}`, 'plan')
    }
  }, [activeTab, enabledAddons, addonsLoaded, tripPluginIds, pluginsLoaded])

  const handleTabChange = (rawTabId: string): void => {
    // A core tab a plugin replaced is gone from the bar, but a programmatic jump
    // (e.g. onNavigateToFiles) could still target it and render a dead panel with
    // no active pill — fall back to the plan view like the invalid-tab guard does.
    const tabId = replacedTabs.has(rawTabId) ? 'plan' : rawTabId
    setActiveTab(tabId)
    sessionStorage.setItem(`trip-tab-${tripId}`, tabId)
    if (tabId === 'finanzplan') tripActions.loadBudgetItems?.(tripId)
    if (tabId === 'dateien' && (!files || files.length === 0)) tripActions.loadFiles?.(tripId)
  }

  // handleTabChange is where a tab's lazy load and its session memory happen, and
  // the tab we *start* on never goes through it — neither a ?tab= deep link nor a
  // tab restored from a previous visit. Catch both up once per trip, or opening
  // straight into Files shows an empty list.
  const startTabSettled = useRef<number | null>(null)
  useEffect(() => {
    if (!tripId || startTabSettled.current === tripId) return
    startTabSettled.current = tripId
    sessionStorage.setItem(`trip-tab-${tripId}`, activeTab)
    if (activeTab === 'finanzplan') tripActions.loadBudgetItems?.(tripId)
    if (activeTab === 'dateien' && (!files || files.length === 0)) tripActions.loadFiles?.(tripId)
  }, [tripId])
  const {
    leftWidth, rightWidth, leftCollapsed, rightCollapsed, setLeftCollapsed, setRightCollapsed,
    leftHidden, rightHidden, toggleLeft, toggleRight, narrow: narrowPanels,
    startResizeLeft, startResizeRight,
  } = useResizablePanels()
  const { selectedPlaceId, selectedAssignmentId, setSelectedPlaceId, selectAssignment } = usePlaceSelection()
  const [showDayDetail, setShowDayDetail] = useState<Day | null>(null)
  const [dayDetailCollapsed, setDayDetailCollapsed] = useState(false)
  const [showPlaceForm, setShowPlaceForm] = useState<boolean>(false)
  const [editingPlace, setEditingPlace] = useState<Place | null>(null)
  const [prefillCoords, setPrefillCoords] = useState<{ lat: number; lng: number; name?: string; address?: string; website?: string; phone?: string; osm_id?: string; stop_type?: RoadtripStopType | null; duration_minutes?: number } | null>(null)
  const [editingAssignmentId, setEditingAssignmentId] = useState<number | null>(null)
  // Day context of the open form. Set only by the day-scoped entry points (the
  // mobile day toolbar, a long-press on the mobile map); every other opener
  // clears it, so a place added from the pool still lands in the pool (#1998).
  const [placeFormDayId, setPlaceFormDayId] = useState<number | null>(null)
  /**
   * Where in the day the place being added belongs, when the caller knows.
   * Null means the old behaviour: the server appends it at the end.
   */
  const [placeFormPosition, setPlaceFormPosition] = useState<number | null>(null)
  // The position belongs to the form it was opened with and to nothing after it. The
  // day-scoped openers set the day, the form's close clears the coordinates, but the
  // position is written by one opener and read by every save, so a stop handed to the
  // form from the corridor popup once left the next add from any day landing at that
  // same index. Tied to the form being open, the only time it means anything.
  useEffect(() => {
    if (!showPlaceForm) setPlaceFormPosition(null)
  }, [showPlaceForm])
  /**
   * Whether the open place form is asking for a service stop on the drive.
   *
   * Only the road trip's "add manually" sets it, and everything that opens the form for
   * anything else clears it, so the ordinary add, the edit and the corridor hit are the
   * form they have always been.
   */
  const [serviceStopForm, setServiceStopForm] = useState(false)
  /**
   * The kind that form opens on, taken from what the corridor panel was looking for.
   *
   * Beside the flag rather than inside it, because it is written by the same click and
   * read by the same memo, and a second piece of state is cheaper to follow than a flag
   * that is sometimes a boolean and sometimes an object.
   */
  const [serviceStopKind, setServiceStopKind] = useState<RoadtripStopType | null>(null)
  /**
   * The corridor hit waiting to become a stop, while the small popup is open.
   *
   * The full place form is the wrong question for a petrol station — category, price,
   * photo, notes and files are all empty for one — so in road trip mode a hit opens this
   * instead, and the form stays one click away behind "more details".
   */
  const [stopDraft, setStopDraft] = useState<RoadtripStopDraft | null>(null)
  /**
   * A booked night the popup was asked to turn into a pause, waiting for a yes.
   *
   * The switch in the popup reads like a change of stop kind, but the night is a
   * booking row, and the server takes the reservation and the expense written against
   * it down with that row. It is the one write the popup can make that nothing brings
   * back, so it is the one that asks first. The name and the booking title are read
   * once, here, so the dialog does not have to know where either lives.
   */
  const [stayRelease, setStayRelease] = useState<{
    stop: { stopType: RoadtripStopType | null; dwellMinutes: number }
    name: string
    booking: string | null
  } | null>(null)
  const [reservationModalDayId, setReservationModalDayId] = useState<number | null>(null)

  // The bottom-nav "+" opens the new-place form via ?create=place.
  useEffect(() => {
    if (searchParams.get('create') === 'place') {
      setEditingPlace(null); setEditingAssignmentId(null); setPlaceFormDayId(null); setShowPlaceForm(true)
      setSearchParams(p => { p.delete('create'); return p }, { replace: true })
    }
  }, [searchParams])

  // ?tab= has done its job in the state initializer above — drop it so the URL
  // stops claiming a tab the user may have since switched away from. The session
  // memory keeps the choice across a reload.
  useEffect(() => {
    if (searchParams.get('tab') === null) return
    setSearchParams(p => { p.delete('tab'); return p }, { replace: true })
  }, [searchParams])
  const [showTripForm, setShowTripForm] = useState<boolean>(false)
  const [showMembersModal, setShowMembersModal] = useState<boolean>(false)
  const [showReservationModal, setShowReservationModal] = useState<boolean>(false)
  const [editingReservation, setEditingReservation] = useState<Reservation | null>(null)
  const [showBookingImport, setShowBookingImport] = useState<boolean>(false)
  // Which tab opened the importer. Only ever a tie-breaker — see openImportItem.
  const [bookingImportKind, setBookingImportKind] = useState<'transports' | 'bookings'>('bookings')
  const [bookingImportAvailable, setBookingImportAvailable] = useState<boolean>(false)
  const { available: airTrailAvailable } = useAirtrailConnection()
  const [showAirTrailImport, setShowAirTrailImport] = useState<boolean>(false)
  // Pull this user's AirTrail edits as soon as they open the trip, so changes
  // made in AirTrail show up without waiting for the background poll.
  const airtrailSyncedRef = useRef<number | null>(null)
  useEffect(() => {
    if (!airTrailAvailable || !tripId || airtrailSyncedRef.current === tripId) return
    airtrailSyncedRef.current = tripId
    airtrailApi.sync()
      .then(r => { if (r && r.changed > 0) tripActions.loadReservations(tripId) })
      .catch(() => {})
  }, [airTrailAvailable, tripId, tripActions])
  const [bookingForAssignmentId, setBookingForAssignmentId] = useState<number | null>(null)
  const [showTransportModal, setShowTransportModal] = useState<boolean>(false)
  const [editingTransport, setEditingTransport] = useState<Reservation | null>(null)
  const [transportModalDayId, setTransportModalDayId] = useState<number | null>(null)
  // Public transit (#1065): open the TransportModal in its Automated mode, seed
  // the search (change-route), and show the journey view for a saved entry.
  const [transportModalAutomated, setTransportModalAutomated] = useState<boolean>(false)
  const [transitPrefill, setTransitPrefill] = useState<{ from?: { name: string; lat: number; lng: number } | null; to?: { name: string; lat: number; lng: number } | null; time?: string | null } | null>(null)
  const [transitJourney, setTransitJourney] = useState<Reservation | null>(null)

  // The bottom-nav "+" is context-aware per tab: on the Bookings / Transports tabs
  // it opens the booking / transport modal via ?create=reservation|transport
  // (place is handled above, expense in CostsPanel). #1349
  useEffect(() => {
    const intent = searchParams.get('create')
    if (intent === 'reservation') {
      setEditingReservation(null); setBookingForAssignmentId(null); setShowReservationModal(true)
      setSearchParams(p => { p.delete('create'); return p }, { replace: true })
    } else if (intent === 'transport') {
      setEditingTransport(null); setTransportModalDayId(null); setShowTransportModal(true)
      setSearchParams(p => { p.delete('create'); return p }, { replace: true })
    }
  }, [searchParams])
  // Review-before-save import: each parsed item pre-fills the normal edit modal so
  // the user checks/fixes it, then saves. A ref drives the queue (no stale closures).
  const [reservationPrefill, setReservationPrefill] = useState<BookingReviewDraft | null>(null)
  const [transportPrefill, setTransportPrefill] = useState<BookingReviewDraft | null>(null)
  const [importReviewActive, setImportReviewActive] = useState(false)
  const importQueueRef = useRef<BookingImportPreviewItem[]>([])
  // The files this import was parsed from, so each reviewed booking can attach its source doc.
  const importSourceFilesRef = useRef<File[]>([])
  // The tab the items under review came from. A ref, not the bookingImportKind
  // state: the parse outlives navigation and reload, and the review is triggered
  // by the global widget, so by then the state has remounted back to its default.
  // The value comes off the persisted job (#2076).
  const importKindRef = useRef<'transports' | 'bookings'>('bookings')
  // Manual route planning: off by default, toggled from the day-plan footer. Mode
  // is per-session and selects which travel time the connectors show — either a
  // built-in OSRM profile or a plugin route profile ('plugin:<id>/<profile>').
  // Per-trip route visibility. `null` = the user has never said anything, which
  // is what lets the mobile map switch it on by default; an explicit false has to
  // survive every later map entry, and it used to be clobbered on each one (#2003).
  const routeStorageKey = tripId ? `trek:day-route:${tripId}` : null
  const [routeChoice, setRouteChoice] = useState<boolean | null>(() => {
    if (typeof window === 'undefined' || !routeStorageKey) return null
    const raw = window.localStorage.getItem(routeStorageKey)
    return raw === 'true' ? true : raw === 'false' ? false : null
  })
  const routeShown = routeChoice === true
  const setRouteShown = useCallback((v: boolean | ((prev: boolean) => boolean)) => {
    setRouteChoice(prev => {
      const next = typeof v === 'function' ? v(prev === true) : v
      if (routeStorageKey && typeof window !== 'undefined') {
        window.localStorage.setItem(routeStorageKey, String(next))
      }
      return next
    })
  }, [routeStorageKey])
  // The mobile map opens with the day's route drawn — a default, not a choice, so
  // it never overwrites an explicit off and is never written to storage itself.
  const autoShowRoute = useCallback(() => {
    setRouteChoice(prev => (prev === null ? true : prev))
  }, [])
  // What the planner maps actually draw. The persisted toggle can rehydrate as
  // true while no day is selected yet (trip re-entry resets the selection, and
  // a second click on the day header clears it) — without a day context the
  // per-day transit filter is off, so the map would draw every automated
  // transport in the trip (#2019).
  const transitRoutesShown = routeShown && selectedDayId != null
  const [routeProfile, setRouteProfile] = useState<string>('driving')
  // Whole-trip route overview (#1736): every day's route at once, each in its own
  // colour. Per trip and per session like road trip mode — it answers "what does the
  // whole thing look like", which is a question you ask of one trip, not a preference.
  const [overviewShown, setOverviewShown] = useState<boolean>(() => sessionStorage.getItem(`trip-overview-${tripId}`) === '1')
  const toggleOverview = useCallback(() => {
    setOverviewShown(prev => {
      const next = !prev
      sessionStorage.setItem(`trip-overview-${tripId}`, next ? '1' : '0')
      return next
    })
  }, [tripId])
  // The recorded route from Dawarich (#2279), per trip and per session for the
  // same reason as the overview above: it answers "what actually happened on
  // this trip", which is a question about one trip rather than a preference.
  const [dawarichTrailShown, setDawarichTrailShown] = useState<boolean>(
    () => sessionStorage.getItem(`trip-dawarich-${tripId}`) === '1',
  )
  const toggleDawarichTrail = useCallback(() => {
    setDawarichTrailShown(prev => {
      const next = !prev
      sessionStorage.setItem(`trip-dawarich-${tripId}`, next ? '1' : '0')
      return next
    })
  }, [tripId])
  // Fetched here rather than in MapViewAuto so the desktop and the phone share
  // one request, and so the pill that toggles it can show why there is no line.
  const dawarichTrail = useDawarichTrail(tripId, dawarichTrailShown)

  const [fitKey, setFitKey] = useState<number>(0)
  const initialFitTripId = useRef<number | null>(null)
  const [mobileSidebarOpen, setMobileSidebarOpen] = useState<'left' | 'right' | null>(null)
  const mobilePlanScrollTopRef = useRef<number>(0)
  const mobilePlacesScrollTopRef = useRef<number>(0)
  const [deletePlaceId, setDeletePlaceId] = useState<number | null>(null)
  const [deletePlaceIds, setDeletePlaceIds] = useState<number[] | null>(null)
  /**
   * The sentence the delete question adds when a night is booked at one of the places.
   *
   * The server takes a booked night down with its place, and with the night the
   * booking made for it and the expense written against that booking. The question
   * itself only names the place, and those are the rows the traveller least expects
   * to lose, so the dialog says so before the yes. The expense list is loaded with
   * the costs tab, not here, so the sentence speaks of any expense rather than
   * counting them. Null when nothing beyond the place is at stake.
   */
  const bookedNightsNote = useCallback((placeIds: number[]): string | null => {
    const stays = tripAccommodations.filter(stay => stay.place_id != null && placeIds.includes(stay.place_id))
    if (stays.length === 0) return null
    const names = [...new Set(stays.map(stay => allPlaces.find(p => p.id === stay.place_id)?.name ?? stay.place_name ?? ''))]
      .filter(Boolean)
    const bookings = stays
      .map(stay => reservations.find(r => r.accommodation_id != null && Number(r.accommodation_id) === stay.id)?.title
        ?? stay.reservation_title ?? null)
      .filter((title): title is string => !!title)
    const name = names.join(', ')
    return bookings.length > 0
      ? t('trip.confirm.deletePlaceBooked', { name, booking: bookings.join(', ') })
      : t('trip.confirm.deletePlaceNight', { name })
  }, [tripAccommodations, allPlaces, reservations, t])
  const deletePlaceNote = useMemo(
    () => (deletePlaceId ? bookedNightsNote([deletePlaceId]) : null),
    [deletePlaceId, bookedNightsNote],
  )
  const deletePlacesNote = useMemo(
    () => (deletePlaceIds?.length ? bookedNightsNote(deletePlaceIds) : null),
    [deletePlaceIds, bookedNightsNote],
  )

  useEffect(() => {
    if (!trip) return
    if (initialFitTripId.current === trip.id) return
    const hasGeoPlaces = places.some(p => p.lat != null && p.lng != null)
    if (!hasGeoPlaces) return
    initialFitTripId.current = trip.id
    setFitKey(k => k + 1)
  }, [trip, places])

  useEffect(() => {
    // The server runs the import when EITHER kitinerary or the LLM parser is
    // there (booking-import.service.ts), so gating the entry point on kitinerary
    // alone hid a working feature on LLM-only instances (#2007).
    healthApi.features().then(f => setBookingImportAvailable(f.bookingImport || f.aiParsing)).catch(() => {})
  }, [])

  const connectionsStorageKey = tripId ? `trek:visible-connections:${tripId}` : null
  // Per-trip route-visibility preference — null means "never touched", which
  // falls back to the account-wide map_always_show_routes default (see
  // connectionsVisibility.ts). That fallback is purely computed, never
  // written, so flipping the account setting later doesn't silently override
  // a trip you've already made an explicit choice on.
  const [storedConnections, setStoredConnections] = useState<StoredConnections | null>(() => {
    if (typeof window === 'undefined' || !connectionsStorageKey) return null
    return parseStoredConnections(window.localStorage.getItem(connectionsStorageKey))
  })
  useEffect(() => {
    if (typeof window === 'undefined' || !connectionsStorageKey || !storedConnections) return
    window.localStorage.setItem(connectionsStorageKey, JSON.stringify(storedConnections))
  }, [connectionsStorageKey, storedConnections])
  const alwaysShowRoutesDefault = settings.map_always_show_routes === true
  const routableReservationIds = useMemo(
    () => reservations.filter(isRoutableReservation).map(r => r.id),
    [reservations]
  )
  const effectiveConnections = useMemo(
    () => resolveEffectiveConnections(storedConnections, alwaysShowRoutesDefault),
    [storedConnections, alwaysShowRoutesDefault]
  )
  const visibleConnections = useMemo(
    () => resolveVisibleConnectionIds(effectiveConnections, routableReservationIds),
    [effectiveConnections, routableReservationIds]
  )
  const allConnectionsShown = effectiveConnections.mode === 'all-except'
  const toggleConnection = useCallback((id: number) => {
    setStoredConnections(prev => toggleConnectionId(prev, alwaysShowRoutesDefault, id))
  }, [alwaysShowRoutesDefault])
  const toggleAllConnections = useCallback(() => {
    setStoredConnections(prev => flipAllConnectionsMode(prev, alwaysShowRoutesDefault))
  }, [alwaysShowRoutesDefault])
  const [mapTransportDetail, setMapTransportDetail] = useState<Reservation | null>(null)

  // Layout is width-driven (isMobile); the drag bridge is pointer-driven (isTouch).
  // Conflating them is what left a tablet's places list undraggable-but-unscrollable (#1432).
  const isTouch = useIsTouch()

  // Start photo fetches during splash screen so images are ready when map mounts
  useEffect(() => {
    if (isLoading || !places || places.length === 0 || !placesPhotosEnabled) return
    for (const p of places) {
      if (p.image_url) continue
      const cacheKey = p.google_place_id || p.osm_id || `${p.lat},${p.lng}`
      if (!cacheKey || getCached(cacheKey)) continue
      const photoId = p.google_place_id || p.osm_id
      if (photoId || (p.lat && p.lng)) {
        fetchPhoto(cacheKey, photoId || `coords:${p.lat}:${p.lng}`, p.lat, p.lng, p.name)
      }
    }
  }, [isLoading, places])

  // Load the trip. loadTrip hydrates every trip-scoped slice (days, places,
  // packing, todo, budget, reservations, files) so offline hydration is uniform
  // and there's no cross-trip bleed; members/accommodations load alongside.
  useEffect(() => {
    if (tripId) {
      tripActions.loadTrip(tripId).catch(() => { toast.error(t('trip.toast.loadError')); navigate('/dashboard') })
      loadAccommodations()
      if (isEffectivelyOffline()) {
        offlineDb.tripMembers.where('tripId').equals(Number(tripId)).toArray()
          .then(rows => setTripMembers(rows))
          .catch(() => {})
      } else {
        refreshMembers()
      }
    }
  }, [tripId])

  // Accommodations live in this hook's local state, so store-level refreshes
  // (remote trip date change, reconnect hydration) nudge us via this event (#1288).
  useEffect(() => {
    const onRefresh = () => loadAccommodations()
    window.addEventListener('accommodations:refresh', onRefresh)
    return () => window.removeEventListener('accommodations:refresh', onRefresh)
  }, [loadAccommodations])

  useTripWebSocket(tripId)

  // Same filter the places sidebar renders — shared via the store so tab
  // switches can't desync the marker set from the filter UI (#1541).
  const placesFilter = useTripStore((s) => s.placesFilter)
  const placesCategoryFilter = useTripStore((s) => s.placesCategoryFilter)

  const [expandedDayIds, setExpandedDayIds] = useState<Set<number> | null>(null)

  const mapPlaces = useMemo(() => {
    // Build set of place IDs assigned to collapsed days
    const hiddenPlaceIds = new Set<number>()
    if (expandedDayIds) {
      for (const [dayId, dayAssignments] of Object.entries(assignments)) {
        if (!expandedDayIds.has(Number(dayId))) {
          for (const a of dayAssignments) {
            if (a.place?.id) hiddenPlaceIds.add(a.place.id)
          }
        }
      }
      // Don't hide places that are also assigned to an expanded day
      for (const [dayId, dayAssignments] of Object.entries(assignments)) {
        if (expandedDayIds.has(Number(dayId))) {
          for (const a of dayAssignments) {
            if (a.place?.id) hiddenPlaceIds.delete(a.place.id)
          }
        }
      }
    }

    // Planned place IDs — needed by both the 'unplanned' filter (exclude them) and
    // the new 'planned' filter (keep only them). With a day selected, 'planned'
    // follows it like the other filters do; with no day selected it keeps showing
    // the whole plan (#2024). 'unplanned' always uses the whole-trip set — a place
    // assigned to any day is not unplanned.
    const plannedIds = placesFilter === 'unplanned' || placesFilter === 'planned'
      ? (placesFilter === 'planned' && selectedDayId
        ? plannedPlaceIdsForDay(selectedDayId, days, { assignments, accommodations: tripAccommodations, reservations })
        : plannedPlaceIds({ assignments, accommodations: tripAccommodations, reservations }))
      : null

    return places.filter(p => {
      if (!p.lat || !p.lng) return false
      if (placesFilter === 'tracks' && !p.route_geometry) return false
      if (placesCategoryFilter.size > 0) {
        if (p.category_id == null) {
          if (!placesCategoryFilter.has('uncategorized')) return false
        } else if (!placesCategoryFilter.has(String(p.category_id))) return false
      }
      // Collapsed-day declutter hides a day's stops on every filter EXCEPT 'planned':
      // there the user asked to see the whole plan on the map, so a collapsed day
      // must not drop its planned places.
      if (placesFilter !== 'planned' && hiddenPlaceIds.has(p.id)) return false
      if (placesFilter === 'unplanned' && plannedIds && plannedIds.has(p.id)) return false
      if (placesFilter === 'planned' && plannedIds && !plannedIds.has(p.id)) return false
      return true
    })
  }, [places, placesCategoryFilter, placesFilter, assignments, expandedDayIds, selectedDayId, days, tripAccommodations, reservations])

  const { route, routeSegments, routeVias, routeInfo, setRoute, setRouteInfo, updateRouteForDay } = useRouteCalculation({ assignments } as any, selectedDayId, routeShown, routeProfile, tripAccommodations)
  // Road trip mode already draws the whole trip its own way, so the overview stands
  // down there rather than drawing a second set of lines over it.
  const overviewActive = overviewShown && !roadtripMode
  const tripOverview = useTripRouteOverview(tripId, days, assignments, reservations, tripAccommodations, routeProfile, overviewActive)

  // Road trip mode reads the whole trip, not the selected day, so it owns its own legs.
  // Passing no days while the mode is off keeps it inert — no routing requests, no state.
  const roadtripActive = !!enabledAddons.roadtrip && roadtripMode
  // The phone's own way into the drive, and the reason line 148 above stays as it is.
  //
  // `roadtripMode` is not a view switch, it is a data switch: `assignments` and
  // `places` are derived from it for the whole hook, and every permanently mounted
  // sheet of the phone shell reads those same lists. Letting the phone flip it would
  // bring back exactly the regressions the comment up there describes, on paths that
  // never touch a tab. The second tap on a day chip opens the day sheet, the More
  // button opens the PDF export.
  //
  // So the phone feeds the routing round instead, and nothing else. Once the tab has
  // been opened the feed stays on for as long as the trip is: a tab switch must not
  // throw away legs that cost a rate-limited request each.
  const roadtripTabSeen = useRef(false)
  if (activeTab === 'roadtrip') roadtripTabSeen.current = true
  const roadtripFeedActive = !!enabledAddons.roadtrip
    && (roadtripMode || (isMobile && (activeTab === 'roadtrip' || roadtripTabSeen.current)))
  const roadtripPreferencesState = useLoadRoadtripSettings(tripId, !!enabledAddons.roadtrip)
  useEffect(() => {
    if (roadtripPreferencesState.failed) toast.error(t('common.error'))
  }, [roadtripPreferencesState.failed, toast, t])
  const dailyTimesActive = !!dayWindow(roadtripSettings.roadtrip_day_start, roadtripSettings.roadtrip_day_end)
  // Fed from the same flag as the routing round: without the boundaries the phone
  // would draw a drive that never ends for the night.
  const dayBoundaries = useDayBoundaries(tripId, roadtripFeedActive && dailyTimesActive, assignments)
  useEffect(() => { if (dayBoundaries.stale) toast.error(t('trip.toast.loadError')) }, [dayBoundaries.stale, toast, t])
  const resetDayBoundaries = dayBoundaries.editable && dayBoundaries.boundaries.length && can('day_edit', trip) ? async () => {
    try {
      for (const boundary of dayBoundaries.boundaries) await dayBoundaries.save(boundary.day_number, null)
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  } : undefined
  // Fed whenever the addon is on, not only while the mode is being looked at.
  // The three handlers that re-anchor a day's vias — assign, remove, reorder —
  // are reachable from the place inspector in both modes, and with an empty list
  // they computed an empty correction and wrote nothing while the server kept
  // every via pointing at a position that had moved. Deleting a stop with the
  // switch off then left the detour on the wrong leg, for the traveller and for
  // a collaborator who never turned the mode on at all.
  const roadtripVias = useRoadtripVias(tripId, !!enabledAddons.roadtrip)
  const refuel = useRefuelSearch()
  const roadtripRoutes = useRoadtripRoutes(
    tripId,
    roadtripFeedActive && roadtripPreferencesState.ready ? days : EMPTY_DAYS,
    // Deliberately the stored list, not the filtered one: the drive wants the
    // service stops and the night a lodging booking put on the map, and the filter
    // above only exists to keep those out of a day list read as a plan.
    roadtripFeedActive ? storedAssignments : assignments,
    routeProfile,
    roadtripVias.byDay,
    dayBoundaries.boundaries,
    tripAccommodations,
    roadtripFeedActive ? reservations : EMPTY_RESERVATIONS,
  )
  /**
   * The bookings the drive is seamed by, drawn as their own arcs beside the roads: a
   * flight's route on the road trip map is the booking's line, the same one the day plan
   * draws, so the ride shows where the road stops (#2428). On top of whatever the reader
   * switched on by hand under Days.
   */
  const roadtripConnections = useMemo(() => {
    const rides = carrierReservationIds(roadtripRoutes.days)
    return rides.length ? [...new Set([...visibleConnections, ...rides])] : visibleConnections
  }, [roadtripRoutes.days, visibleConnections])
  // Lives here rather than in the panel because the map draws what it finds.
  // The trip comes with it for the vehicle: an electric car looks for chargers rather
  // than for pumps, and that preference is stored per trip.
  // The phone searches under a smaller ceiling: fewer boxes, a capped retry pass and a
  // deadline, because a search that keeps the radio warm costs battery somebody is
  // navigating on. Which stretch of the day it asks about is decided per search.
  const roadtripCorridor = useRoadtripCorridor(roadtripRoutes, tripId, isMobile ? PHONE_CORRIDOR_OPTIONS : undefined)
  // Applying a track is a long job — a routing round trip per refinement — so it lives
  // above the dialog: a component that unmounted halfway would leave the day holding
  // half a chain of vias.
  const followTrack = useFollowTrack(tripId, places, roadtripRoutes, roadtripVias)
  /** How many vias each day carries, for the rail's badge. */
  const roadtripViaCounts = useMemo(() => {
    const counts: Record<number, number> = {}
    for (const [dayId, list] of Object.entries(roadtripVias.byDay)) counts[Number(dayId)] = list.length
    return counts
  }, [roadtripVias.byDay])

  const handleSelectDay = useCallback((dayId: number | null, skipFit?: boolean) => {
    tripActions.setSelectedDay(dayId)
    if (!skipFit) setFitKey(k => k + 1)
    setMobileSidebarOpen(null)
    updateRouteForDay(dayId)
  }, [updateRouteForDay])

  const handlePlaceClick = useCallback((placeId: number | null, assignmentId?: number | null) => {
    if (assignmentId) {
      selectAssignment(assignmentId, placeId)
    } else {
      setSelectedPlaceId(placeId)
    }
    if (placeId) { setShowDayDetail(null); setLeftCollapsed(false); setRightCollapsed(false) }
  }, [selectAssignment, setSelectedPlaceId])

  const handleMarkerClick = useCallback((placeId?: number) => {
    if (placeId === undefined) {
      setSelectedPlaceId(null)
      return
    }
    // Find every assignment for this place (same place can sit on several
    // days / be planned twice in one day). Cycle through them on repeated
    // marker clicks so the sidebar highlight jumps to the next occurrence
    // instead of leaving the user confused.
    const allAssignments = Object.values(useTripStore.getState().assignments || {}).flat()
    const matching = allAssignments.filter(a => a?.place?.id === placeId)

    if (matching.length === 0) {
      setSelectedPlaceId(selectedPlaceId === placeId ? null : placeId)
    } else if (matching.length === 1) {
      const only = matching[0]
      if (selectedAssignmentId === only.id) {
        setSelectedPlaceId(null)
      } else {
        selectAssignment(only.id, placeId)
      }
    } else {
      const currentIdx = matching.findIndex(a => a.id === selectedAssignmentId)
      const nextIdx = currentIdx === -1 ? 0 : currentIdx + 1
      if (nextIdx >= matching.length) {
        // cycled past the last occurrence — clear selection so the next
        // click starts fresh at occurrence 0.
        setSelectedPlaceId(null)
      } else {
        selectAssignment(matching[nextIdx].id, placeId)
      }
    }
    setLeftCollapsed(false); setRightCollapsed(false)
  }, [selectAssignment, selectedAssignmentId, selectedPlaceId, setSelectedPlaceId])

  const handleMapClick = useCallback(() => {
    setSelectedPlaceId(null)
  }, [])

  const handleMapContextMenu = useCallback(async (e, dayId?: number | null) => {
    if (!can('place_edit', trip)) return
    e.originalEvent?.preventDefault()
    const { lat, lng } = e.latlng
    setPrefillCoords({ lat, lng })
    setEditingPlace(null)
    setEditingAssignmentId(null)
    setPlaceFormDayId(dayId ?? null)
    setServiceStopForm(false)
    setShowPlaceForm(true)
    try {
      const { mapsApi } = await import('../../api/client')
      const data = await mapsApi.reverse(lat, lng, language)
      if (data.name || data.address) {
        setPrefillCoords(prev => prev ? { ...prev, name: data.name || '', address: data.address || '' } : prev)
      }
    } catch { /* best effort */ }
  }, [language])

  // Open the Add-Place form pre-filled from an OSM "explore" POI marker — all the
  // data already comes from the POI, so no reverse-geocode is needed.
  const openAddPlaceFromPoi = useCallback((
    poi: { lat: number; lng: number; name: string; address: string | null; website: string | null; phone: string | null; osm_id: string },
    dayId?: number | null,
    /** Index within that day. Omitted, the place is appended, which is what every caller did before. */
    position?: number | null,
    /**
     * What the corridor popup had worked out before the traveller asked for the full
     * form. Without it, leaving the popup by "more details" quietly turned a fuel stop
     * into a numbered destination that counts in every total.
     */
    stop?: { stopType: RoadtripStopType | null; dwellMinutes: number } | null,
  ) => {
    if (!can('place_edit', trip)) return
    setPrefillCoords({
      lat: poi.lat,
      lng: poi.lng,
      name: poi.name,
      address: poi.address || '',
      website: poi.website || undefined,
      phone: poi.phone || undefined,
      osm_id: poi.osm_id,
      stop_type: stop?.stopType ?? null,
      duration_minutes: stop?.dwellMinutes,
    })
    setEditingPlace(null)
    setEditingAssignmentId(null)
    setPlaceFormDayId(dayId ?? null)
    setPlaceFormPosition(position ?? null)
    setServiceStopForm(false)
    setShowPlaceForm(true)
  }, [trip])

  /**
   * Adding a POI straight off the map, with the day it belongs to.
   *
   * In road trip mode that is the day being searched: without it the place lands in the
   * unplanned pool, and neither column shows that pool while road trip mode is on, so a
   * just-added stop disappears without a trace. Outside road trip mode nothing changes —
   * `undefined` keeps the old "let the user pick" behaviour.
   *
   * Memoised because both map renderers rebuild every POI marker whenever this callback's
   * identity changes.
   */
  const roadtripDayId = roadtripCorridor.day?.dayId ?? null
  const { insertIndexFor: roadtripInsertIndexFor } = roadtripCorridor
  const roadtripDayNumber = roadtripCorridor.day?.dayNumber ?? 0
  /**
   * The check-out days a night started on `dayId` can end on.
   *
   * Ordered by the trip's own day order rather than by array position, the same rule the
   * day detail panel follows: a day list can be sorted by anything, and a hotel booked
   * out on "the next day" has to mean the next day of the trip.
   */
  const overnightOptions = useCallback((dayId: number) => {
    const ordered = [...days].sort((a, b) => getDayOrder(a, days) - getDayOrder(b, days))
    const from = ordered.findIndex(d => d.id === dayId)
    const rest = from < 0 ? ordered : ordered.slice(from)
    return {
      days: rest.map(d => ({ id: d.id, number: d.day_number ?? 0, date: d.date ?? null })),
      // The day after, or this one when it is the last: a night on the final day of a
      // trip has nowhere else to end.
      defaultEndDayId: rest[1]?.id ?? rest[0]?.id ?? dayId,
    }
  }, [days])

  const handlePoiClick = useCallback((poi: Parameters<typeof openAddPlaceFromPoi>[0]) => {
    if (!can('place_edit', trip)) return
    // A corridor hit knows how far along the drive it sits, so it can go straight into
    // the chain in driving order instead of being dragged there afterwards.
    //
    // Gated on the FEED, not on road trip mode: the phone never turns that mode on (it
    // is a data switch the mobile sheets cannot survive, see `roadtripFeedActive`), so
    // reading it here sent every hit found on the stage map into the full place form
    // instead, losing the stop kind, the stay, and the position worked out just above.
    const hit = roadtripFeedActive && 'alongKm' in poi ? (poi as unknown as CorridorPoi) : null
    if (hit && roadtripDayId != null) {
      const displayed = roadtripRoutes.days.find(d => d.dayId === roadtripDayId)
      const insert = displayed && roadtripInsertion(displayed, roadtripInsertIndexFor(hit))
      if (!insert) return
      setStopDraft({
        poi: hit,
        arrivalTime: displayed ? stopArrival(displayed, roadtripInsertIndexFor(hit), hit.alongKm) : null,
        ...insert,
        dayNumber: roadtripDayNumber,
        // Only for a hit somebody could sleep at, and it is what gives the popup its
        // second mode. The check-out options are the days from this one on in travel
        // order; the default is the next one, which is what a night usually means.
        ...(isOvernightCategory(hit.category) ? { overnight: overnightOptions(insert.dayId) } : {}),
      })
      return
    }
    const selected = roadtripRoutes.days.find(d => d.dayId === roadtripDayId)
    const target = selected && roadtripInsertion(selected, selected.stops.length)
    openAddPlaceFromPoi(poi, roadtripFeedActive ? target?.dayId ?? roadtripDayId : undefined)
  }, [openAddPlaceFromPoi, roadtripFeedActive, roadtripDayId, roadtripDayNumber, roadtripInsertIndexFor, roadtripRoutes.days, overnightOptions, can, trip])

  /**
   * The stops of a day as the road trip counts them, in the order it drives them.
   *
   * This is the index space `after_order_index` lives in: sorted by `order_index`, and
   * filtered to the rows that have coordinates, because a place the map cannot put
   * anywhere is not a point the router is given. Built from the STORED list, the same
   * one the routing round and the server count over. The day list read as a plan
   * hides the stop a lodging booking put on the day and, behind the switch, the
   * service stops; the handlers that correct a day's vias run in that mode too, and a
   * plan measured on the shorter list deleted a via behind a hidden hotel or pinned
   * it to a leg nobody drew. Built from the list rather than from `roadtripRoutes` so
   * it also answers for a day with one stop or none, which is exactly the day a stop
   * gets pushed onto when a leg turns out too long.
   */
  const roadtripStopsOf = useCallback((dayId: number) =>
    (storedAssignments[String(dayId)] ?? [])
      .slice()
      .sort((a, b) => (a.order_index ?? 0) - (b.order_index ?? 0))
      .filter(a => typeof a.place?.lat === 'number' && typeof a.place?.lng === 'number'),
  [storedAssignments])

  /**
   * Where a place dropped at `position` in a day's row list lands among the stops the
   * road trip counts.
   *
   * The day plan hands over a row index and the store splices the new row in at that
   * index, so the stop's place in the chain is the number of routable rows ahead of
   * it, not the index itself: a row without coordinates is never a stop.
   */
  const roadtripIndexOf = useCallback((dayId: number, position: number) =>
    (storedAssignments[String(dayId)] ?? [])
      .slice()
      .sort((a, b) => (a.order_index ?? 0) - (b.order_index ?? 0))
      .slice(0, Math.max(0, position))
      .filter(a => typeof a.place?.lat === 'number' && typeof a.place?.lng === 'number')
      .length,
  [storedAssignments])

  /**
   * Which half of a split leg a via belongs to, measured on the road actually driven.
   *
   * Both the via and the new stop are projected onto the day's current routed line, so
   * the comparison is "which one does the car reach first" rather than a straight-line
   * guess. The line already includes the detour the via causes, so the via sits exactly
   * on it and its position along the drive is exact.
   *
   * Falls back to keeping the via on the first half. A projection only fails when the
   * point is nowhere near the drive, and in that case leaving the anchor where it was is
   * the answer that changes least.
   */
  const viaLiesBefore = useCallback((dayId: number, at: { lat: number; lng: number }) => {
    const line: LatLng[] = (roadtripRoutes.days.find(d => d.dayId === dayId)?.geometry ?? [])
      .map(([lat, lng]) => ({ lat, lng }))
    const insertAt = line.length ? projectOntoRoute(at, line)?.alongKm ?? null : null
    return (via: { lat: number; lng: number }) => {
      if (insertAt === null) return true
      const viaAt = projectOntoRoute({ lat: via.lat, lng: via.lng }, line)?.alongKm
      return viaAt === undefined || viaAt === null ? true : viaAt < insertAt
    }
  }, [roadtripRoutes.days])

  /**
   * How a day's vias move when a place at `at` lands on it at row `position`, or at its
   * end without one. Null when none do: appending moves nothing, and a place without
   * coordinates is never a stop.
   *
   * Worked out before the stop lands, the same way the road-trip popup does it: once the
   * list has shifted there is no record of which leg each via was drawn for. The
   * predicate decides which side of the new stop a via falls on when it is dropped into
   * the middle of a leg.
   */
  const viasAfterInsert = useCallback((dayId: number, position: number | undefined, at: { lat?: number | null; lng?: number | null } | undefined) => {
    const stopsBefore = roadtripStopsOf(dayId)
    // The position is a row index in the day list, the anchors count stops.
    const insertAt = position === undefined ? stopsBefore.length : roadtripIndexOf(dayId, position)
    if (insertAt >= stopsBefore.length || typeof at?.lat !== 'number' || typeof at?.lng !== 'number') return null
    return reanchorAfterInsert(roadtripVias.byDay[dayId] ?? [], insertAt, viaLiesBefore(dayId, { lat: at.lat, lng: at.lng }))
  }, [roadtripStopsOf, roadtripIndexOf, roadtripVias.byDay, viaLiesBefore])

  /**
   * Saves a corridor hit as a stop: the place itself, then its position in the day.
   *
   * `stop_type` is what makes it a fuel stop rather than a place that happens to sell
   * fuel — the road-trip kinds are their own dimension, deliberately not one of the
   * traveller's editable categories, so the palette and the meaning stay put.
   */
  /**
   * Stores one of the three driving limits.
   *
   * Straight to the settings store rather than through the offline queue: these are
   * per-user preferences on the settings table, the same path the map provider and the
   * distance unit take, and they are read locally the moment they change.
   */
  /**
   * A colour per drawn line, or none at all.
   *
   * Off is not "all the same colour" but an absent array: the map then paints the blue it
   * has always painted, so a trip that never turns this on renders byte for byte the way
   * it did.
   */
  /**
   * Days folded down to their header in the road trip rail.
   *
   * Its own state rather than the day plan's `expandedDayIds`: that one is owned by
   * `DayPlanSidebar`, which republishes it from its own state every time it mounts — so a
   * day folded in the rail would spring back open the moment the other view was visited.
   */
  const [collapsedRoadtripDays, setCollapsedRoadtripDays] = useState<Set<number>>(new Set())
  const toggleRoadtripDay = useCallback((dayId: number) => {
    setCollapsedRoadtripDays(prev => {
      const next = new Set(prev)
      if (!next.delete(dayId)) next.add(dayId)
      return next
    })
  }, [])

  /**
   * The road trip's lines, minus the days that are folded away.
   *
   * Folding a card takes that day off the map, which is most of what folding is for: a
   * rail entry can be scrolled past, a line across the map cannot be looked away from.
   * `lineDays` runs parallel to `lines`, so both are filtered in one pass and the colours
   * stay lined up with what is left.
   */
  const roadtripMapLines = useMemo(() => {
    if (!collapsedRoadtripDays.size) return roadtripRoutes.lines
    const hidden = new Set(
      roadtripRoutes.days.filter(d => collapsedRoadtripDays.has(d.dayId)).map(d => d.dayNumber),
    )
    return roadtripRoutes.lines.filter((_, i) => !hidden.has(roadtripRoutes.lineDays[i]))
  }, [roadtripRoutes.lines, roadtripRoutes.lineDays, roadtripRoutes.days, collapsedRoadtripDays])

  /**
   * The map's places with the folded cards' stops taken out.
   *
   * A second pass rather than a branch inside `mapPlaces`: that memo runs long before the
   * road trip is routed, and the answer here needs the CHAINS — a card is a date, and
   * after a night drive it holds stops stored on the day before (`nightSpill.ts`), so
   * what a folded card hides is what is drawn on it, not what is filed under its day.
   *
   * A place still drawn on some other card stays, which is the rule the day plan's own
   * declutter follows.
   */
  const roadtripMapPlaces = useMemo(() => {
    const plannedIds = new Set(Object.values(assignments).flat().map(a => a.place_id))
    // The hotel a day sets out from or ends at is drawn with its drive whether or not a day
    // still holds its stop: with that stop removed, the line and the walk to the door ended
    // at a spot with no pin, where the phone's stage map has one (`stagePlaceIds`).
    for (const day of roadtripRoutes.days) {
      for (const stop of day.stops) if (stop.bookend) plannedIds.add(stop.placeId)
    }
    const plannedPlaces = mapPlaces.filter(p => plannedIds.has(p.id))
    if (!collapsedRoadtripDays.size) return plannedPlaces
    const hidden = new Set<number>()
    for (const day of roadtripRoutes.days) {
      if (!collapsedRoadtripDays.has(day.dayId)) continue
      for (const stop of day.stops) if (!stop.automaticNight) hidden.add(stop.placeId)
    }
    for (const day of roadtripRoutes.days) {
      if (collapsedRoadtripDays.has(day.dayId)) continue
      for (const stop of day.stops) if (!stop.automaticNight) hidden.delete(stop.placeId)
    }
    return plannedPlaces.filter(p => !hidden.has(p.id))
  }, [mapPlaces, assignments, roadtripRoutes.days, collapsedRoadtripDays])

  // The recorded route follows the same folds as the places above, so a
  // collapsed day does not leave its line behind on the map. Keyed on the joined
  // dates rather than on the Set, because `days` changes identity on every store
  // update and the GL overlay rebuilds its source whenever this reference moves.
  const dawarichHiddenKey = useMemo(
    () => collapsedDayDates(days, expandedDayIds, roadtripActive ? collapsedRoadtripDays : null).join('|'),
    [days, expandedDayIds, roadtripActive, collapsedRoadtripDays],
  )
  const dawarichHiddenDates = useMemo(
    () => (dawarichHiddenKey ? new Set(dawarichHiddenKey.split('|')) : null),
    [dawarichHiddenKey],
  )

  const roadtripLineColors = useMemo(
    () => {
      if (!roadtripSettings.roadtrip_day_colors) return undefined
      const hidden = new Set(
        roadtripRoutes.days.filter(d => collapsedRoadtripDays.has(d.dayId)).map(d => d.dayNumber),
      )
      return roadtripRoutes.lineDays.filter(n => !hidden.has(n)).map(n => dayColor(n))
    },
    [roadtripSettings.roadtrip_day_colors, roadtripRoutes.lineDays, roadtripRoutes.days, collapsedRoadtripDays],
  )

  const saveRoadtripLimit = useCallback(async (key: string, value: number | string | boolean) => {
    try {
      if (!can('day_edit', trip) || !roadtripPreferencesState.ready) return
      const userId = useAuthStore.getState().user?.id
      if (!userId) return
      const preferences = await roadtripPreferencesRepo.update(tripId, { [key]: value })
      publishRoadtripPreferences(userId, tripId, preferences)
    } catch {
      toast.error(t('places.saveError'))
    }
  }, [tripId, trip, can, roadtripPreferencesState.ready, toast, t])

  const saveStopDraft = useCallback(async (
    { stopType, dwellMinutes }: { stopType: RoadtripStopType | null; dwellMinutes: number },
    { releaseStay = false }: { releaseStay?: boolean } = {},
  ) => {
    if (!stopDraft) return
    const { poi, dayId, position } = stopDraft
    const accommodationId = stopDraft.editing?.accommodationId
    // Turning a booked night into a pause deletes the booking, and with it the
    // reservation and the expense the server keeps against it. The popup stays open
    // behind the question, so a no leaves the traveller exactly where they were.
    if (accommodationId && !releaseStay) {
      const stay = tripAccommodations.find(s => s.id === accommodationId)
      const booking = reservations.find(r => r.accommodation_id != null && Number(r.accommodation_id) === accommodationId)?.title
        ?? stay?.reservation_title ?? null
      setStayRelease({ stop: { stopType, dwellMinutes }, name: poi.name, booking })
      return
    }
    try {
      if (stopDraft.editing) {
        await tripActions.updatePlace(tripId, stopDraft.editing.placeId, { stop_type: stopType, duration_minutes: dwellMinutes })
        if (accommodationId) {
          // The night is what was switched off, not the stop: it stays where it is
          // in the drive and becomes an ordinary pause.
          applyStayStops(await accommodationsApi.delete(tripId, accommodationId, { keepStop: true }))
          await loadAccommodations()
        }
        updateRouteForDay(dayId)
        setStopDraft(null)
        return
      }
      const place = await tripActions.addPlace(tripId, {
        name: poi.name,
        lat: poi.lat,
        lng: poi.lng,
        address: poi.address || null,
        website: poi.website || undefined,
        phone: poi.phone || undefined,
        osm_id: poi.osm_id,
        duration_minutes: dwellMinutes,
        stop_type: stopType,
      })
      if (place?.id) {
        // Worked out BEFORE the stop lands, against the day as it stands and the road as
        // it is currently driven — once the list has shifted there is no record of which
        // leg each via was drawn for.
        const plan = reanchorAfterInsert(
          roadtripVias.byDay[dayId] ?? [],
          position,
          viaLiesBefore(dayId, { lat: poi.lat, lng: poi.lng }),
        )
        await tripActions.assignPlaceToDay(tripId, dayId, place.id, position)
        // Awaited before the day re-routes: the routing effect reads the anchors against
        // the new stop list, so a correction landing after it would draw the wrong road
        // first and the right one a moment later.
        await roadtripVias.reanchor(dayId, plan)
        updateRouteForDay(dayId)
      }
      setStopDraft(null)
      toast.success(t('trip.toast.placeAdded'))
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [stopDraft, tripId, tripActions, updateRouteForDay, toast, t, roadtripVias, viaLiesBefore, loadAccommodations, tripAccommodations, reservations])

  /** The yes to the question above: the same save, this time allowed to drop the night. */
  const confirmStayRelease = useCallback(async () => {
    const pending = stayRelease
    setStayRelease(null)
    if (pending) await saveStopDraft(pending.stop, { releaseStay: true })
  }, [stayRelease, saveStopDraft])

  const saveStopDraftAsNight = useCallback(async ({ endDayId, checkIn, checkOut }: {
    endDayId: number
    checkIn: string
    checkOut: string
  }) => {
    if (!stopDraft) return
    const { poi, dayId, position } = stopDraft
    try {
      if (stopDraft.editing) {
        const booking = { place_id: stopDraft.editing.placeId, start_day_id: dayId, end_day_id: endDayId, check_in: checkIn || null, check_out: checkOut || null }
        // The answer carries the day stop the booking moved or added. The socket
        // deliberately skips the session that sent the request, so without folding
        // it in the one person whose rail still shows the night at its old place in
        // the chain is the one who just moved its check-in.
        const written = stopDraft.editing.accommodationId
          ? await accommodationsApi.update(tripId, stopDraft.editing.accommodationId, booking)
          : await accommodationsApi.create(tripId, booking)
        applyStayStops(written)
        // A night seated by a new check-in renumbers its neighbours as well, and the
        // answer names only the night. The day is read back whole rather than guessed.
        if (written?.movedAssignment) await tripActions.refreshDays(tripId)
        await tripActions.updatePlace(tripId, stopDraft.editing.placeId, { stop_type: poi.category === 'campsite' ? 'campsite' : 'hotel' })
        await loadAccommodations()
        updateRouteForDay(dayId)
        setStopDraft(null)
        return
      }
      const place = await tripActions.addPlace(tripId, {
        name: poi.name,
        lat: poi.lat,
        lng: poi.lng,
        address: poi.address || null,
        website: poi.website || undefined,
        phone: poi.phone || undefined,
        osm_id: poi.osm_id,
        stop_type: poi.category === 'campsite' ? 'campsite' : 'hotel',
      })
      if (place?.id) {
        const plan = reanchorAfterInsert(
          roadtripVias.byDay[dayId] ?? [],
          position,
          viaLiesBefore(dayId, { lat: poi.lat, lng: poi.lng }),
        )
        await tripActions.assignPlaceToDay(tripId, dayId, place.id, position)
        await accommodationsApi.create(tripId, {
          place_id: place.id,
          start_day_id: dayId,
          end_day_id: endDayId,
          ...(checkIn ? { check_in: checkIn } : {}),
          ...(checkOut ? { check_out: checkOut } : {}),
        })
        await loadAccommodations()
        await roadtripVias.reanchor(dayId, plan)
        updateRouteForDay(dayId)
      }
      setStopDraft(null)
      toast.success(t('roadtrip.stay.nightAdded'))
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [stopDraft, tripId, tripActions, updateRouteForDay, toast, t, roadtripVias, viaLiesBefore, loadAccommodations])

  /**
   * Turns a stop on the drive into a pause, or back into a destination.
   *
   * The only difference between the two is `stop_type`, which decides whether the stop
   * takes a number, counts in the day's total and appears in the printout. So this is one
   * field on one place, and the rail redraws itself off the store the moment it lands.
   */
  const setRoadtripStopKind = useCallback(async (placeId: number, kind: RoadtripStopType | null) => {
    if (!can('place_edit', trip)) return
    try {
      await tripActions.updatePlace(tripId, placeId, { stop_type: kind })
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [tripId, tripActions, toast, t, can, trip])

  /**
   * How full THIS stop fills the tank, from the road trip rail.
   *
   * The same shape as the kind above and for the same reason: one field on one place,
   * with the rail redrawing off the store the moment it lands. Null hands the stop back
   * to whatever the traveller set as their own default, which is what every stop does
   * until somebody has an opinion about one.
   */
  const setRoadtripStopFill = useCallback(async (placeId: number, percent: number | null) => {
    if (!can('place_edit', trip)) return
    try {
      await tripActions.updatePlace(tripId, placeId, { fill_percent: percent })
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [tripId, tripActions, toast, t, can, trip])

  /**
   * Moves a stop within its day, from the road trip rail.
   *
   * The rail reports only "this assignment, from here to there" and the full order is
   * rebuilt here, from the day's COMPLETE assignment list rather than from what the rail
   * shows. That matters: the rail hides stops without coordinates, and both
   * `reorderAssignments` and the WebSocket handler rebuild the day's array purely from the
   * ids they are given — anything left out would vanish from the store, for every session
   * watching the trip.
   *
   * Within one day only. Moving between days stays in the day plan, where empty and
   * one-stop days are visible and can be dropped onto; the rail leaves them out, so a day
   * would disappear from under the cursor mid-gesture.
   *
   * No confirmation prompt for a stop with a pinned time, unlike the day plan: the rail
   * recomputes the cascade immediately and marks a stop it can no longer reach in time.
   * Showing the consequence is better than asking about it in advance.
   */
  const reorderRoadtripStop = useCallback(async (dayId: number, assignmentId: number, toIndex: number) => {
    if (!can('day_edit', trip)) return
    const all = assignments[String(dayId)] ?? []
    const ordered = [...all].sort((a, b) => (a.order_index ?? 0) - (b.order_index ?? 0))
    const fromIdx = ordered.findIndex(a => a.id === assignmentId)
    if (fromIdx === -1) return

    // `toIndex` counts stops as the rail lists them; map it onto the full list, which may
    // hold rows the rail never showed.
    const visible = ordered.filter(a => typeof a.place?.lat === 'number' && typeof a.place?.lng === 'number')
    const target = visible[Math.min(Math.max(toIndex, 0), visible.length - 1)]
    if (!target || target.id === assignmentId) return
    const toIdx = ordered.findIndex(a => a.id === target.id)
    if (toIdx === -1 || toIdx === fromIdx) return

    const next = [...ordered]
    const [moved] = next.splice(fromIdx, 1)
    next.splice(toIdx, 0, moved)

    // In the rail's own index space, which is the one the anchors are counted in. A stop
    // without coordinates never entered that space, so moving it changes nothing there.
    const fromVis = visible.findIndex(a => a.id === assignmentId)
    const plan = fromVis === -1
      ? null
      : reanchorAfterReorder(roadtripVias.byDay[dayId] ?? [], fromVis, toIndex, visible.length)

    try {
      await tripActions.reorderAssignments(tripId, dayId, next.map(a => a.id))
      if (plan) await roadtripVias.reanchor(dayId, plan)
      updateRouteForDay(dayId)
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [assignments, tripId, tripActions, updateRouteForDay, toast, t, can, trip, roadtripVias])

  /**
   * The stop whose length is being set, or null while the dialog is closed.
   *
   * Held here rather than in the rail because the write goes through `tripActions`, and
   * the rail is a list — putting a dialog's state inside a row means it dies whenever the
   * list re-renders around it.
   */
  const [stayDraft, setStayDraft] = useState<StayDraft | null>(null)

  /**
   * Whether the day ends at this stop, from BOTH the things that can end it.
   *
   * A stop carries an `end_day` flag, and a day can also be closed by a manual boundary
   * filed against that stop (`to_assignment_id === null`). `setRoadtripEndDay` already
   * knows about both and clears whichever is set, so a surface reading only the flag shows
   * a day end as off, and the tap meant to switch it on deletes the boundary instead. The
   * question is asked here once rather than answered again per surface.
   */
  const roadtripEndsDayAt = useCallback(
    (stop: RoadtripStop): boolean =>
      !!stop.endDay
      || dayBoundaries.boundaries.some(b => b.to_assignment_id === null && b.from_assignment_id === stop.assignmentId),
    [dayBoundaries.boundaries],
  );

  /**
   * Returns whether the day end actually moved.
   *
   * It reports rather than throws, because it shows its own toast and a second one from the
   * caller would be the same news twice. A caller that flipped a switch optimistically has
   * to hear about a refusal all the same, or it sits there showing a state the trip never
   * reached: the phone sheet's catch was unreachable for exactly this reason.
   */
  const setRoadtripEndDay = useCallback(async (stop: RoadtripStop): Promise<boolean> => {
    if (!dailyTimesActive || !can('day_edit', trip)) return false
    try {
      const manual = dayBoundaries.boundaries.find(b => b.to_assignment_id === null && b.from_assignment_id === stop.assignmentId)
      if (manual) {
        await dayBoundaries.save(manual.day_number, null)
        if (!stop.endDay) return true
      }
      await tripActions.setAssignmentEndDay(tripId, stop.ownerDayId, stop.assignmentId, !stop.endDay)
      return true
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
      return false
    }
  }, [dailyTimesActive, can, trip, tripActions, tripId, toast, t, dayBoundaries.boundaries, dayBoundaries.save])

  /**
   * How long the traveller stays at one stop.
   *
   * Writes `places.duration_minutes`, which the schedule has read since it was written
   * and which nothing in TREK has ever been able to set — the road trip is the only place
   * the value means anything, so it is the only place that edits it.
   *
   * Zero rather than null to clear: the update statement folds a null into "leave it
   * alone" (`COALESCE(?, duration_minutes)`), so a null could give a stop a stay but
   * never take one away. The rail reads zero and absent as the same thing.
   */
  const setRoadtripStay = useCallback(async (placeId: number, minutes: number) => {
    if (!can('place_edit', trip)) return
    try {
      await tripActions.updatePlace(tripId, placeId, { duration_minutes: minutes })
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [tripId, tripActions, toast, t, can, trip])

  /**
   * Moves a stop onto another day, from the road trip rail.
   *
   * Split from `reorderRoadtripStop` because it is a different call with a different
   * failure mode: `moveAssignment` writes to two days, and the rail has to be able to
   * reach days it draws no drive for — a day with one stop or none is exactly what a
   * stop gets moved onto when a leg turns out to be too long for one day.
   *
   * The target index counts the stops the rail shows on that day; an empty day takes
   * position 0.
   */
  const moveRoadtripStopToDay = useCallback(async (
    fromDayId: number,
    assignmentId: number,
    toDayId: number,
    toIndex: number,
  ) => {
    if (!can('day_edit', trip)) return
    if (fromDayId === toDayId) return
    const target = (assignments[String(toDayId)] ?? [])
      .slice()
      .sort((a, b) => (a.order_index ?? 0) - (b.order_index ?? 0))
    const visible = target.filter(a => typeof a.place?.lat === 'number' && typeof a.place?.lng === 'number')
    // Map the rail's own count onto the day's full list, which may hold rows it hides.
    const anchor = visible[Math.min(Math.max(toIndex, 0), Math.max(visible.length - 1, 0))]
    const at = anchor ? target.findIndex(a => a.id === anchor.id) : target.length

    // Both days shift at once, and each needs its own correction: the stop leaves a gap
    // on one side and opens one on the other. No geometry is measured for the arriving
    // day — its roads are about to be different anyway, so there is nothing stable to
    // measure a via against.
    const fromStops = roadtripStopsOf(fromDayId)
    const fromVis = fromStops.findIndex(a => a.id === assignmentId)
    const fromPlan = fromVis === -1
      ? null
      : reanchorAfterRemove(roadtripVias.byDay[fromDayId] ?? [], fromVis, fromStops.length)
    const toVis = Math.min(Math.max(toIndex, 0), visible.length)
    const toPlan = fromVis === -1
      ? null
      : reanchorAfterInsert(roadtripVias.byDay[toDayId] ?? [], toVis, () => true)

    try {
      await tripActions.moveAssignment(tripId, assignmentId, fromDayId, toDayId, at < 0 ? target.length : at)
      if (fromPlan) await roadtripVias.reanchor(fromDayId, fromPlan)
      if (toPlan) await roadtripVias.reanchor(toDayId, toPlan)
      updateRouteForDay(fromDayId)
      updateRouteForDay(toDayId)
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [assignments, tripId, tripActions, updateRouteForDay, toast, t, can, trip, roadtripVias, roadtripStopsOf])

  const routeAlternatives = useRouteAlternatives()
  /**
   * Which offered route the pointer is on, so the map can light that one up.
   *
   * Lives here rather than in the bar because the map draws it and the bar reports it —
   * neither owns it, and passing it through the page would put state in a wiring
   * container the Page pattern keeps stateless.
   */
  const [highlightedAlternative, setHighlightedAlternative] = useState<number | null>(null)
  // Closing the picker has to clear it, or the next one opens with a road already lit.
  useEffect(() => {
    if (!routeAlternatives.open) setHighlightedAlternative(null)
  }, [routeAlternatives.open])

  // Leaving road trip mode closes it too. The switch sits in the left sidebar and
  // is reachable while the bar is open over the map, and the overlay depends only
  // on the picker — so flipping the mode off left pale blue alternatives, their
  // casings and their drive-time pills drawn on an ordinary planner map, with no
  // road trip UI left to dismiss them from.
  //
  // The gate is where the picker can be seen, not the mode. `roadtripActive` is false
  // on a phone by design (see `roadtripMode`), so gating on it alone closed a picker
  // the phone had just opened, on the very next render. On the phone the picker lives
  // on the drive tab, so it stays open there and closes once the tab is left. At desk
  // width `isMobile` is false and this is exactly `roadtripActive`, as it always was.
  const alternativesShown = roadtripActive || (isMobile && roadtripFeedActive && activeTab === 'roadtrip')
  useEffect(() => {
    if (!alternativesShown) routeAlternatives.close()
  }, [alternativesShown, routeAlternatives])

  /**
   * The offered routes as the map draws them: line, colour, and the label that sits on
   * the road. Built here rather than in the page so the page stays a wiring container
   * and both renderers get the identical shape.
   */
  const alternativeOverlays = useMemo(
    () => buildAlternativeOverlays(routeAlternatives.open?.routes, {
      fastest: t('roadtrip.alt.fastest'),
      current: t('roadtrip.alt.current'),
      noMotorway: t('roadtrip.alt.noMotorway'),
      noToll: t('roadtrip.alt.noToll'),
      noFerry: t('roadtrip.alt.noFerry'),
    }, routeAlternatives.open?.engine),
    [routeAlternatives.open, t],
  )

  /**
   * The stretch of map the offered routes cover, handed to whichever renderer is up.
   *
   * Opening the picker without moving the camera means weighing three roads you cannot
   * see. Derived from the overlays rather than from the two endpoints so the frame holds
   * the whole of every alternative, including one that swings far off the direct line.
   * Empty while nothing is open, and the map is told to do nothing with an empty list —
   * so closing the picker leaves the view where the user put it.
   */
  const alternativeFocusPoints = useMemo(
    () => alternativeOverlays.flatMap(o => o.coordinates),
    [alternativeOverlays],
  )

  /**
   * What the map should bring into view.
   *
   * Refuel offers win while they are open, and for the reason they exist at all: somebody
   * is being asked to accept a stop, and a stop off the edge of the map cannot be judged.
   * They are the newer, smaller and more specific answer, so they take the view from the
   * alternatives rather than being averaged with them into a frame that shows neither.
   */
  const automaticPoints = useAutomaticDayPoints(roadtripRoutes, collapsedRoadtripDays)
  const focusRoadtripPoint = useCallback((lat: number, lng: number) => {
    refuel.close()
    routeAlternatives.close()
    automaticPoints.focusPoint(lat, lng)
  }, [refuel, routeAlternatives, automaticPoints])
  const roadtripMapVias = automaticPoints.markers
  const dayBoundaryControls = useMemo<DayBoundaryControls | undefined>(() => {
    if (!dayBoundaries.editable || !can('day_edit', trip) || !roadtripRoutes.boundaryPath?.length) return undefined
    return {
      path: roadtripRoutes.boundaryPath,
      hint: t('roadtrip.window.dragHint'),
      move: async (day, boundary) => {
        const next = dayBoundaries.boundaries.filter(b => b.day_number !== day)
        if (boundary) next.push(boundary)
        const issue = roadtripRoutes.validateBoundaries?.(next)
        if (boundary && issue) { toast.error(t(`roadtrip.window.${issue}`, { days: MAX_TRIP_DAYS })); return false }
        try { return await dayBoundaries.save(day, boundary) }
        catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')); return false }
      },
    }
  }, [dayBoundaries.editable, dayBoundaries.boundaries, dayBoundaries.save, can, trip, roadtripRoutes, t, toast])
  const mapFocusPoints = useMemo<[number, number][]>(
    () => (refuel.offered.length
      ? refuel.offered.map(p => [p.lat, p.lng] as [number, number])
      : alternativeFocusPoints.length ? alternativeFocusPoints : automaticPoints.focusPoints ?? alternativeFocusPoints),
    [refuel.offered, alternativeFocusPoints, automaticPoints.focusPoints],
  )

  /**
   * The rail as it stands now, for a choice that is written several router answers after
   * the render that started it. Checked against before anything is written.
   */
  const railDaysRef = useRef<Parameters<typeof railLegAt>[0]>(roadtripRoutes.days)
  // The days with a single stop as well, in day order: they draw no card, but a drive
  // into the day after one leaves from its stop, and a choice for that drive is filed there.
  useEffect(() => {
    railDaysRef.current = [...roadtripRoutes.days, ...roadtripRoutes.quietDays].sort((a, b) => a.dayNumber - b.dayNumber)
  }, [roadtripRoutes.days, roadtripRoutes.quietDays])

  /**
   * Asks the rail's own router for other ways of one drive on a card.
   *
   * The picker is handed everything about the leg as the rail has it: the road it is on
   * now, which heads the list as the current one; where a choice would be written; and
   * the router with the leg's own mode and avoided classes, not the trip-wide profile.
   *
   * The drive arriving at the head of a connected card is asked about the same way, as
   * the pair from the last stop of the day before to the card's first. Its router is the
   * one the rail drives that seam with, under the card it arrives on, and a choice is
   * filed behind the stop it leaves, where the map already files a point dropped on it.
   * It used to be the one drive on the rail that could not be offered another way.
   */
  const askRouteAlternatives = useCallback((dayId: number, drive: RailDrive) => {
    const day = roadtripRoutes.days.find(d => d.dayId === dayId)
    const found = day ? railDriveOn(day, drive) : null
    const router = found ? roadtripRoutes.legRouter?.(found.from, found.to, dayId) : undefined
    if (!found || !router) return
    if (openOn(routeAlternatives.open, dayId, drive)) {
      routeAlternatives.close()
      return
    }
    const { from, to, seg, line } = found
    routeAlternatives.ask({
      dayId,
      drive,
      from: { lat: from.lat, lng: from.lng },
      to: { lat: to.lat, lng: to.lng },
      driven: { coordinates: line ?? [], distance: seg.distance, duration: seg.duration },
      // The vias of a leg are filed behind the stop it leaves, on the day that stop is
      // stored on, which on a card holding a night drive or a drive in from yesterday is
      // not the card's own day.
      anchor: { dayId: from.ownerDayId, afterIndex: from.ownerIndex },
      ends: { from: from.assignmentId, to: to.assignmentId },
      router,
    })
  }, [roadtripRoutes, routeAlternatives])

  /**
   * Taking one of the offered routes: pinned, proven, and only then written.
   *
   * Saved as vias, not as a stored polyline: a polyline goes stale with the next OSM update
   * and with every stop that moves, while a via keeps forcing the router back onto this
   * road for as long as the road exists. But a via only holds a road the router is willing
   * to drive through it, and nothing used to check that: a point on a ferry was pulled to
   * the pier and the day went the long way round, and a way weighed away from motorways
   * kept the motorway after its one pinned point. So the rail's own router is asked first
   * (`pinAlternative`), and a way it will not follow is not saved and says why.
   *
   * The pins replace the leg's vias in one write rather than joining them. Appending put a
   * new point behind the old one and routed out to each in turn, a zigzag matching neither
   * the preview nor the distance printed on it; and one delete per via meant a full re-route
   * between each of them. A write that fails is reported and leaves the picker open:
   * swallowed, it closed on a leg that still carried its via, and not even the reload ran
   * to contradict the traveller.
   *
   * A refusal is said twice: as a toast, and to the bar (`settle`), which keeps it beside
   * the offers and announces it. A leg the rail drew with OSRM standing in for an engine
   * that did not answer is asked for again once a choice holds, since the road the router
   * chose is not the one on the map: taking the router's own road there wrote nothing and
   * left the stand-in line in place, which read as a click that did nothing.
   */
  const chooseRouteAlternative = useCallback(async (index: number) => {
    const open = routeAlternatives.open
    const offer = open?.routes[index]
    if (!open || !offer) return
    // Choosing the road already being driven changes nothing.
    if (offer.current) { routeAlternatives.close(); return }
    // One choice at a time: the map line can be clicked while a chip's choice is checked.
    if (alternativesBusy(open)) return
    // Vias are written online only, so a choice that could not be kept is not checked.
    if (!roadtripVias.editable) { toast.error(t('roadtrip.alt.offline')); return }

    const signal = routeAlternatives.prove(index)
    let proof: PinProof
    try {
      proof = await pinAlternative({ offer, current: open.routes.find(r => r.current), route: open.route, signal })
    } catch {
      if (signal.aborted) return
      routeAlternatives.settle(t('roadtrip.alt.failed'))
      // The desk's bar says it in its own status line; a toast on top covered that line
      // and printed the same sentence twice. The phone's bar has no room for a sentence.
      if (isMobile) toast.error(t('roadtrip.alt.failed'))
      return
    }
    if (signal.aborted) return
    if (!proof.held) {
      const refusal = t(proof.fellBack ? 'roadtrip.alt.failed' : 'roadtrip.alt.notHeld')
      const hint = proof.fellBack ? null : refusalHint(offer, proof.last, t)
      routeAlternatives.settle(hint ? `${refusal} ${hint}` : refusal)
      if (isMobile) {
        toast.error(refusal, 6000)
        if (hint) toast.info(hint, 8000)
      }
      return
    }

    // The chain may have moved while the router was asked: a stop dragged, a collaborator's
    // edit arriving. Pins worked out for this leg are only written where it still runs.
    const { anchor, ends } = open
    const leg = railLegAt(railDaysRef.current, anchor)
    if (!leg || leg.from.assignmentId !== ends.from || leg.to.assignmentId !== ends.to) {
      toast.error(t('roadtrip.alt.legChanged'), 6000)
      routeAlternatives.close()
      return
    }
    // The router's own road on a leg nothing bends is already what is driven, unless OSRM
    // drew the leg in its engine's place. A write routes the leg again by itself; without
    // one the rail is asked to, and either way the picker says why the map may still hold
    // the stand-in line for a moment, or for as long as that engine does not answer.
    const bent = viasLeaving(leg.from, roadtripVias.byDay[anchor.dayId] ?? []).length > 0
    if (proof.pins.length || bent) {
      try {
        await roadtripVias.addMany(
          anchor.dayId,
          proof.pins.map(pin => ({ after_order_index: anchor.afterIndex, lat: pin.lat, lng: pin.lng })),
          [anchor.afterIndex],
        )
      } catch (err: unknown) {
        // Said even when the picker has moved on in the meantime: the write was asked for.
        const message = err instanceof Error ? err.message : t('common.unknownError')
        if (!signal.aborted) routeAlternatives.settle(message)
        toast.error(message)
        return
      }
    } else if (open.standIn) {
      roadtripRoutes.reroute?.()
    }
    if (open.standIn) toast.info(t('roadtrip.alt.standIn'), 8000)
    // A picker opened on another leg while this was written belongs to that leg now.
    if (!signal.aborted) routeAlternatives.close()
  }, [routeAlternatives, roadtripVias, roadtripRoutes, toast, t, isMobile])

  /**
   * A click on the drawn route puts a via there, and the drive is redrawn through it.
   *
   * Which pair of stops it belongs between comes from projecting the click onto the
   * day's routed geometry — the same measurement the corridor search uses, so "after the
   * third stop" means the same thing everywhere. The day is the one whose line was hit,
   * found by trying each day's geometry and keeping the closest.
   */
  /**
   * Which stop of which day a point belongs behind, measured along the drive.
   *
   * Shared by placing a via and by dragging one, because it is the same question both
   * times and the answer has to be recomputed both times. A drag used to send only the
   * new coordinates, so a via pulled past the stop it used to precede kept claiming the
   * earlier leg: the route then ran out to the point and back before carrying on, which
   * looks exactly like a drag that did nothing.
   */
  const anchorFor = useCallback((lat: number, lng: number, onlyDayId?: number) => {
    // `terminal` names the anchor when it is one end of a ride rather than a stored stop
    // (#2428). Nothing can be filed against a terminal: it stands in for no assignment,
    // so a via anchored to it would be stored at a position that belongs to the stop
    // after it and bend that stop's road instead. The callers decide what to refuse.
    //
    // `bookendLeg` says the drive leaves or reaches a booked night's hotel at the day's
    // edge, which files nothing either: the morning's hotel has no index of its own, and
    // the evening's drive is reached from the index that shapes the road into tomorrow.
    // `card` is where the point fell on the card it was measured on, the day and the index
    // of the stop before it there, -1 for the drive in before the card's first stop.
    type Anchor = {
      dayId: number
      afterIndex: number
      offRouteKm: number
      terminal: CarrierTerminal['role'] | null
      bookendLeg: boolean
      card: { dayId: number; index: number }
    }
    // A road the day drives twice, out of the hotel in the morning and past it again later,
    // is on the line twice, and the closer pass wins by metres at most. A pass that can
    // take a via beats one on the hotel's drive, which files nothing, by this much.
    const SAME_ROAD_KM = 0.03
    const beats = (c: Anchor, b: Anchor | null) => {
      if (!b) return true
      if (c.bookendLeg === b.bookendLeg) return c.offRouteKm < b.offRouteKm
      return c.bookendLeg ? c.offRouteKm + SAME_ROAD_KM < b.offRouteKm : c.offRouteKm <= b.offRouteKm + SAME_ROAD_KM
    }
    // Which stop of this card the point falls behind, for a hit measured on its line.
    const readAnchor = (day: (typeof roadtripRoutes.days)[number], hit: CorridorHit, stopsAlong: number[]): Anchor | null => {
      // Before the card's first stop means a drive that arrives here but leaves from a
      // stop on the card BEFORE this one: the incoming night drive (`nightSpill.ts`), or
      // on a trip with connected days the drive from where yesterday ended, which is drawn
      // at the head of this card in yesterday's colour. Anchoring either to this card's
      // first stop would file the via on the leg AFTER that stop, and the route would run
      // forward, double back to the point, and carry on.
      //
      // Asked of the distance rather than of the index, because the index cannot answer
      // it: `insertIndexForAlong` clamps to at least 1 for any list of two or more, and
      // the rail only ever publishes cards with two stops or more. Written against the
      // index this read as a guard and behaved as dead code, so a via dropped on the
      // night stretch went to the first drawn stop after all, which is the exact failure
      // the paragraph above describes.
      const arrivedFrom = day.spills?.find(sp => sp.at === 0)?.fromStop ?? day.arrivingFrom
      if (arrivedFrom && hit.alongKm < (stopsAlong[0] ?? 0)) {
        const owner = arrivedFrom.ownerDayId ?? day.dayId
        if (onlyDayId !== undefined && owner !== onlyDayId) return null
        return {
          dayId: owner,
          afterIndex: arrivedFrom.ownerIndex ?? 0,
          offRouteKm: hit.offRouteKm,
          terminal: arrivedFrom.carrier?.role ?? null,
          bookendLeg: !!arrivedFrom.bookend || !!day.stops[0]?.bookend,
          card: { dayId: day.dayId, index: -1 },
        }
      }
      const at = insertIndexForAlong(stopsAlong, hit.alongKm) - 1
      // Named by the day the anchor stop is STORED on and its position there, not by the
      // card and the position within it. A card is a date and can hold stops from the day
      // before (`nightSpill.ts`), so those two numbers differ on any day that received a
      // night drive — and a via filed under the card's numbers matches no stop when the
      // route is next built, which reads as a drag that did nothing at all.
      const anchor = day.stops[at]
      if (!anchor) return null
      // Falling back to the card's own numbers is not a guard against a bug, it is the
      // meaning: a stop that names no other day IS stored on the card it is drawn on,
      // which is every stop on a trip that never drives past midnight.
      const owner = anchor.ownerDayId ?? day.dayId
      // A drag stays on its own day; a fresh click may land wherever it landed.
      if (onlyDayId !== undefined && owner !== onlyDayId) return null
      return {
        dayId: owner,
        afterIndex: anchor.ownerIndex ?? at,
        offRouteKm: hit.offRouteKm,
        terminal: anchor.carrier?.role ?? null,
        bookendLeg: !!anchor.bookend || !!day.stops[at + 1]?.bookend,
        card: { dayId: day.dayId, index: at },
      }
    }
    let best: Anchor | null = null
    for (const day of roadtripRoutes.days) {
      // NOT `day.dayId !== onlyDayId`. A dragged via has to stay on the day it is stored
      // on, but that day's stops are no longer all on the card of the same name: after a
      // night drive they are drawn on the next one (`nightSpill.ts`). Filtering by card
      // measured the new position against a line that no longer covers those stops — a
      // point dragged near Brandenburg was projected onto the short remainder of card 1
      // and came back anchored to its last stop, which put the via on the night drive
      // itself and pushed the stop before it over midnight.
      //
      // So every card is measured, and the answer is filtered by the day the ANCHOR is
      // stored on. Same promise, kept against the stops rather than against the card.
      if (day.geometry.length < 2) continue
      const spine = day.geometry.map(([la, ln]) => ({ lat: la, lng: ln }))
      const hit = projectOntoRoute({ lat, lng }, spine)
      if (!hit) continue
      if (best && hit.offRouteKm >= best.offRouteKm + SAME_ROAD_KM) continue
      // Which stop the via follows: the last one the car passes before reaching it.
      const stopsAlong = day.stops.map(stop => projectOntoRoute({ lat: stop.lat, lng: stop.lng }, spine)?.alongKm ?? 0)
      let candidate = readAnchor(day, hit, stopsAlong)
      if (candidate?.bookendLeg) {
        // Landed on the drive to or from the hotel, a road the day can drive again between
        // two of its own stops. Asked once more of the stretch between the day's first and
        // last stop, and taken when that answer lies on the same road.
        const first = day.stops.findIndex(stop => !stop.bookend)
        const last = day.stops.length - 1 - [...day.stops].reverse().findIndex(stop => !stop.bookend)
        const fromKm = stopsAlong[first] ?? 0
        const toKm = stopsAlong[last] ?? 0
        const inner = first >= 0 && first < last && fromKm < toKm
          ? projectOntoRoute({ lat, lng }, spine, { fromKm, toKm })
          : null
        const retry = inner && inner.offRouteKm <= hit.offRouteKm + SAME_ROAD_KM ? readAnchor(day, inner, stopsAlong) : null
        if (retry && !retry.bookendLeg) candidate = retry
      }
      if (candidate && beats(candidate, best)) best = candidate
    }
    return best
  }, [roadtripRoutes.days])

  /**
   * Where a place chosen by hand belongs in the drive, as a card and a position in it.
   *
   * `anchorFor` answers in the space a via is STORED in: the day the anchor stop belongs
   * to, and its index there. A stop is placed at a position counted along the card it is
   * drawn on, which is the same thing on every day that does not drive past midnight and
   * a different one on the days that do (`nightSpill.ts`). Translating between the two
   * happens here, once, rather than at whichever surface asked.
   *
   * Deliberately with no distance limit, unlike `addRoadtripVia`: the place this answers
   * for is the charger the corridor search did not find, which is exactly the one sitting
   * further off the drawn line than a via is allowed to be. The projection is the default
   * the dialog offers, never a gate it applies.
   */
  const manualStopTargetFor = useCallback((lat: number, lng: number): ManualStopTarget | null => {
    const anchor = anchorFor(lat, lng)
    // Nothing is stopped at on a flight. Behind an arrival terminal or a hire car's desk
    // is a road, and a stop there is the first stop after landing or after the pick-up.
    if (!anchor || anchor.terminal === 'departure') return null
    // Behind a terminal, and on the drive from the hotel a day sets out from or to the one
    // it ends at, the place goes where it fell on the card. None of them is a stored stop
    // to be found by its index, which each shares with one: after the morning's hotel is
    // before the day's first stop, before the evening's is after its last.
    if (anchor.bookendLeg || anchor.terminal) {
      return { dayId: anchor.card.dayId, position: anchor.card.index + 1, offRouteKm: anchor.offRouteKm }
    }
    for (const day of roadtripRoutes.days) {
      // The stored stop the anchor names, not a terminal or a hotel seated in front of it
      // with the same index, which put the place one stop early.
      const at = day.stops.findIndex(stop => isStoredStop(stop) && stop.ownerDayId === anchor.dayId && stop.ownerIndex === anchor.afterIndex)
      if (at >= 0) return { dayId: day.dayId, position: at + 1, offRouteKm: anchor.offRouteKm }
    }
    // No card draws that stop, which happens while the rail is between rebuilds. Its own
    // numbers are the best answer there is, and `roadtripInsertion` measures them against
    // the card again when the stop actually lands.
    return { dayId: anchor.dayId, position: anchor.afterIndex + 1, offRouteKm: anchor.offRouteKm }
  }, [anchorFor, roadtripRoutes.days])

  /**
   * Adding a stop the corridor search never found.
   *
   * The search reads OpenStreetMap, and a good share of the chargers actually standing
   * at a motorway junction are not in it. The way round it was to leave road trip mode,
   * add the place under Days, drag it onto the right day, come back and mark it a
   * charging stop.
   *
   * So this opens the form the rest of TREK adds places with, on nothing at all: no
   * place, no coordinates, no day. The traveller finds the charger in the form's own
   * typed-ahead search, which is the whole reason to use it, and where the stop belongs
   * is worked out at the save, from what the save carries.
   */
  const openManualRoadtripStop = useCallback((kind: RoadtripStopType | null = null) => {
    if (!can('place_edit', trip)) return
    setEditingPlace(null)
    setEditingAssignmentId(null)
    setPrefillCoords(null)
    // Deliberately nowhere. A corridor hit knows its day and its position before the
    // form opens; this one cannot, because nothing has been chosen yet.
    setPlaceFormDayId(null)
    setPlaceFormPosition(null)
    // Set in the same batch as the flag below, so the kind is already there when the
    // form's opening effect reads the mode out of its closure.
    setServiceStopKind(kind)
    setServiceStopForm(true)
    setShowPlaceForm(true)
  }, [can, trip])

  /**
   * What the place form needs to ask for a service stop, or null for every other use.
   *
   * The legs are flat across the whole drive rather than per card, because the charger
   * the search missed is as likely to be on tomorrow's stretch as on today's. The names
   * travel as plain strings so the form does its own labelling and this stays free of
   * translated text.
   */
  const serviceStopMode = useMemo<ServiceStopMode | null>(() => {
    if (!serviceStopForm) return null
    const panelDay = roadtripCorridor.day
    return {
      defaultKind: serviceStopKind,
      // A day that has not routed has no order to place anything in.
      days: roadtripRoutes.days
        .filter(day => day.geometry.length > 1)
        .map(day => {
          const spine: LatLng[] = day.geometry.map(([la, ln]) => ({ lat: la, lng: ln }))
          const stopsAlong = day.stops.map(stop => projectOntoRoute({ lat: stop.lat, lng: stop.lng }, spine)?.alongKm ?? 0)
          return {
            dayId: day.dayId,
            dayNumber: day.dayNumber,
            stops: day.stops.map(stop => stop.name),
            // Each leg's own road, cut out of the day's line where the two stops it runs
            // between fall on it. The form measures the place against each of these, so
            // the leg it offers first is visibly the nearest one rather than a guess the
            // reader has to take on trust.
            legLines: day.stops.slice(0, -1).map((_, i) =>
              sliceAtMeters(spine, (stopsAlong[i] ?? 0) * 1000, (stopsAlong[i + 1] ?? 0) * 1000)),
          }
        }),
      // The end of the day the panel is looking at, which is what the dialog this
      // replaced did. Offered whatever else has routed, not only when nothing has: with
      // its neighbours drawn and its own line still coming, a day left out of this list
      // is a day a stop meant for it cannot be put on at all.
      appendDay: panelDay
        ? { dayId: panelDay.dayId, dayNumber: panelDay.dayNumber, position: panelDay.stops.length }
        : null,
      targetFor: manualStopTargetFor,
    }
  }, [serviceStopForm, serviceStopKind, roadtripRoutes.days, roadtripCorridor.day, manualStopTargetFor])

  const addRoadtripVia = useCallback(async (lat: number, lng: number) => {
    if (!can('day_edit', trip)) return
    const best = anchorFor(lat, lng)
    // A click that landed on some other line is not a via anywhere. Neither is one on a
    // ride, or on the road out of a terminal: a via is filed by the position of a stored
    // stop, and a terminal is not one.
    if (!best || best.offRouteKm > 2 || best.terminal) return
    // Nor on the drive from or to a booked night's hotel, which says so rather than
    // ignoring the click (`legReroutable`).
    if (best.bookendLeg) { toast.info(t('roadtrip.bookend.noVia')); return }
    try {
      await roadtripVias.add(best.dayId, best.afterIndex, lat, lng)
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [anchorFor, roadtripVias, can, trip, toast, t])

  /** Dragging a via redraws the route through its new position. */
  const moveRoadtripVia = useCallback(async (dayId: number, id: number, lat: number, lng: number) => {
    if (!can('day_edit', trip)) return
    // Measured against this day only. A drag is a drag WITHIN a day: letting the nearest
    // day win, the way placing one does, would hand the via to a neighbouring day whose
    // road happens to pass closer, and it would vanish from the day it was dragged in.
    //
    // No distance guard either. Dragging a via well off the current road is the whole
    // point of dragging it, and refusing that would be refusing the gesture; the anchor
    // just says which leg gets bent, and the router answers the rest.
    const anchor = anchorFor(lat, lng, dayId)
    try {
      await roadtripVias.move(dayId, id, lat, lng, anchor && !anchor.terminal && !anchor.bookendLeg ? anchor.afterIndex : undefined)
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [anchorFor, roadtripVias, can, trip, toast, t])

  /**
   * Somewhere to fill up before this tank runs out.
   *
   * Measured against the day's DRIVING line, the same one the dry point was placed on, so
   * a station's distance along the road is comparable with the distance the fuel lasts.
   * The day's own places go in as well: a pump already on the plan should not be offered
   * beside itself.
   */
  const askRefuel = useCallback((dayId: number, dry: DryPoint & { lat: number; lng: number }) => {
    const day = roadtripRoutes.days.find(d => d.dayId === dayId)
    if (!day) return
    const line = (dry.inboundLine ?? day.drivingGeometry ?? day.geometry).map(([lat, lng]) => ({ lat, lng }))
    if (line.length < 2) return
    const vehicle = roadtripSettings.roadtrip_vehicle
    const refuelTypes = refuelStopTypeFor(vehicle === 'electric' || vehicle === 'combustion' ? vehicle : null)
    let fromAlongKm = 0
    let drivenKm = 0
    for (let i = 0; i <= dry.legIndex; i++) {
      if (refuelTypes.includes(day.stops[i]?.stopType as 'fuel' | 'charging')) fromAlongKm = drivenKm
      const leg = day.legs[i]
      if (leg?.mode === 'driving') drivenKm += (leg.distance ?? 0) / 1000
    }
    void refuel.ask(
      `${dayId}:${dry.legIndex}`,
      { lat: dry.lat, lng: dry.lng },
      line,
      dry.drivenMeters / 1000,
      day.stops.map(stop => ({ lat: stop.lat, lng: stop.lng })),
      fromAlongKm,
    )
  }, [roadtripRoutes.days, refuel, roadtripSettings.roadtrip_vehicle])

  /**
   * Accepting one hands it to the same popup a corridor hit goes through.
   *
   * Deliberately not a direct write: the popup is where the stop kind and the time spent
   * are decided, it defaults both from the category, and every step after it — the place,
   * the assignment at the right position, the via re-anchoring, the re-route — is already
   * correct there and pinned by tests. A second path to the same end would be a second
   * place for it to go wrong.
   */
  const acceptRefuel = useCallback((dayId: number, poi: RefuelCandidate, dry: DryPoint & { lat: number; lng: number }) => {
    if (!can('day_edit', trip)) return
    const day = roadtripRoutes.days.find(d => d.dayId === dayId)
    if (!day) return
    // Before the stop the tank would have run out on, which is the leg the dry point
    // names. A station reached after the day's last stop is tomorrow's problem, and
    // clamping it onto the final leg would re-route the arrival through it.
    let drivenKm = 0
    const stationLeg = day.legs.findIndex(leg => {
      if (leg?.mode !== 'driving') return false
      drivenKm += (leg.distance ?? 0) / 1000
      return poi.alongKm <= drivenKm
    })
    const at = dry.inboundLine ? -dry.legIndex - 1 : Math.min((stationLeg >= 0 ? stationLeg : dry.legIndex) + 1, day.stops.length - 1)
    // That index counts along the CARD, and after a night drive a card is not one stored
    // day: its first stops belong to yesterday. The new stop goes in front of the one it
    // was measured against, so it is that stop's own day and position that place it —
    // written against the card's day it would land in the wrong list, at an index that
    // means something else there.
    const anchor = day.stops[at]
    if (!anchor) return
    refuel.close()
    setStopDraft({ poi, ...roadtripInsertion(day, at)!, dayNumber: day.dayNumber })
  }, [roadtripRoutes.days, refuel, can, trip])

  /** Removing a via lets the drive take the direct road again. */
  const removeRoadtripVia = useCallback(async (dayId: number, id: number) => {
    if (!can('day_edit', trip)) return
    try {
      await roadtripVias.remove(dayId, id)
    } catch (err: unknown) {
      toast.error(err instanceof Error ? err.message : t('common.unknownError'))
    }
  }, [roadtripVias, can, trip, toast, t])

  /**
   * A corridor hit dropped on the map, placed where it was dropped rather than where the
   * corridor projected it.
   *
   * The two differ whenever a drive passes near the same spot twice — a loop, an
   * out-and-back — and the automatic projection can only pick one of them. Dropping says
   * which, and the drop coordinate is projected onto the same routed line the hits were
   * measured along, so the answer is in the same units as everything else.
   *
   * A drop nowhere near the drive is ignored rather than guessed at: adding a stop
   * fifty kilometres off the route because the pointer slipped is worse than nothing
   * happening.
   */
  const dropPoiOnRoute = useCallback((osmId: string, lat: number, lng: number) => {
    if (!can('place_edit', trip)) return
    const hit = roadtripCorridor.visible.find(p => p.osm_id === osmId)
    const day = roadtripCorridor.day
    if (!hit || !day) return
    const at = projectOntoRoute({ lat, lng }, roadtripCorridor.search.spine)
    if (!at || at.offRouteKm > roadtripCorridor.widthKm) return
    const insert = roadtripInsertion(day, roadtripCorridor.insertIndexFor(at))
    if (!insert) return
    setStopDraft({
      poi: hit,
      ...insert,
      dayNumber: day.dayNumber,
    })
  }, [roadtripCorridor, can, trip])

  /** Hands the draft over to the full form, keeping the day and the position it worked out. */
  const stopDraftToForm = useCallback((stop?: { stopType: RoadtripStopType | null; dwellMinutes: number }) => {
    if (!stopDraft) return
    const { poi, dayId, position } = stopDraft
    setStopDraft(null)
    if (stopDraft.editing) {
      const place = places.find(place => place.id === stopDraft.editing?.placeId)
      if (place) {
        setEditingPlace(place)
        setEditingAssignmentId(resolvePoolAssignmentId(assignments, place.id))
        setShowPlaceForm(true)
      }
      return
    }
    // Carries the kind and the dwell the popup had already worked out. Leaving them
    // behind is what turned a fuel stop into a numbered destination on the way to the
    // full form, silently and in every total.
    openAddPlaceFromPoi(poi, dayId, position, stop ?? null)
  }, [stopDraft, openAddPlaceFromPoi, places, assignments])

  /**
   * A place on this trip that came from the same OSM object.
   *
   * The full place form warns about duplicates; without the same check here the popup
   * would be the quickest way to add one petrol station twice.
   */
  const stopDraftDuplicate = useMemo(() => {
    if (stopDraft?.editing || !stopDraft?.poi.osm_id) return null
    return places.find(p => p.osm_id === stopDraft.poi.osm_id)?.name ?? null
  }, [stopDraft, places])

  const handleSavePlace = useCallback(async (data) => {
    const pendingFiles = data._pendingFiles
    delete data._pendingFiles
    // Where a service stop added by hand belongs on the drive. The form worked it out
    // from the coordinates being saved, because until a place was chosen in it there
    // were none to project.
    const serviceStop = data._serviceStop
    delete data._serviceStop
    if (editingPlace) {
      // Always strip time fields from place update — time is per-assignment only.
      // Same for the day-specific note (#2163): it belongs to the assignment,
      // never to the pool place.
      const { place_time, end_time, assignment_notes, ...placeData } = data
      await tripActions.updatePlace(tripId, editingPlace.id, placeData)
      // If editing from assignment context, save time per-assignment
      if (editingAssignmentId) {
        await assignmentsApi.updateTime(tripId, editingAssignmentId, { place_time: place_time || null, end_time: end_time || null })
        // The form only includes assignment_notes when the user changed it, so
        // an untouched note never produces a PUT (#2163). '' clears like null.
        if (assignment_notes !== undefined) {
          await assignmentsApi.updateNotes(tripId, editingAssignmentId, { notes: assignment_notes || null })
        }
        await tripActions.refreshDays(tripId)
      }
      // Upload pending files with place_id
      if (pendingFiles?.length > 0) {
        for (const file of pendingFiles) {
          const fd = new FormData()
          fd.append('file', file)
          fd.append('place_id', String(editingPlace.id))
          try { await tripActions.addFile(tripId, fd) } catch (err) { toast.error(translateApiError(t, err, 'files.uploadError')) }
        }
      }
      toast.success(t('trip.toast.placeUpdated'))
      return { id: editingPlace.id }
    } else {
      const place = await tripActions.addPlace(tripId, data)
      // A card of the rail can draw stops that are STORED on the day before it
      // (`nightSpill.ts`), so a leg named by the card and the position in it is
      // translated once here, the same way every other path into this write is.
      const card = serviceStop && roadtripRoutes.days.find(day => day.dayId === serviceStop.dayId)
      const insert = serviceStop
        ? (card && roadtripInsertion(card, serviceStop.position)) || { dayId: serviceStop.dayId, position: serviceStop.position }
        : null
      const dayId = insert ? insert.dayId : placeFormDayId
      const position = insert ? insert.position : placeFormPosition
      // Added from inside a day? Then it belongs to that day. Without this the
      // place drops into the unplanned pool and, on mobile, into a different
      // screen entirely — which reads as "it wasn't saved" (#1998).
      if (place?.id && dayId != null) {
        // Worked out BEFORE the stop lands, against the day as it stands and the road as
        // it is currently driven: once the list has shifted there is no record of which
        // leg each via was drawn for. A via is stored as (day, after_order_index) and
        // that index is a POSITION in the day's stop list, so a stop dropped into the
        // middle of a routed day pushes every via at or behind it onto the wrong leg and
        // the drawn road runs forward, doubles back and runs out again. Keyed on the
        // position rather than on the service-stop form: a corridor hit handed to the
        // full form carries its position too, and was the one way into the middle of a
        // day that left the vias where they were.
        const plan = position != null && typeof data.lat === 'number' && typeof data.lng === 'number'
          ? reanchorAfterInsert(
            roadtripVias.byDay[dayId] ?? [],
            position,
            viaLiesBefore(dayId, { lat: data.lat, lng: data.lng }),
          )
          : null
        try {
          // With a position the stop lands where it will be driven past, not at the end
          // of the day. The slice has taken one all along; nothing ever passed it.
          await tripActions.assignPlaceToDay(tripId, dayId, place.id, position)
          // Awaited before the day re-routes: the routing effect reads the anchors against
          // the new stop list, so a correction landing after it would draw the wrong road
          // first and the right one a moment later.
          if (plan) await roadtripVias.reanchor(dayId, plan)
          updateRouteForDay(dayId)
        } catch (err: unknown) {
          // The place itself exists; only the day link failed.
          toast.error(err instanceof Error ? err.message : t('common.unknownError'))
        }
      }
      if (pendingFiles?.length > 0 && place?.id) {
        for (const file of pendingFiles) {
          const fd = new FormData()
          fd.append('file', file)
          fd.append('place_id', String(place.id))
          try { await tripActions.addFile(tripId, fd) } catch (err) { toast.error(translateApiError(t, err, 'files.uploadError')) }
        }
      }
      toast.success(t('trip.toast.placeAdded'))
      if (place?.id) {
        const capturedId = place.id
        pushUndo(t('undo.addPlace'), async () => {
          await tripActions.deletePlace(tripId, capturedId)
        })
      }
      // Handed back so the form can link an expense to a place that did not
      // exist a moment ago (#1298), the same way the booking modals work.
      return place?.id ? { id: place.id } : undefined
    }
  }, [editingPlace, editingAssignmentId, placeFormDayId, placeFormPosition, roadtripRoutes.days, tripId, toast, pushUndo, updateRouteForDay, roadtripVias, viaLiesBefore])

  // Open the place editor from any entry point (Places pool, inspector, map).
  // Times live per day-assignment, so when no day is in context resolve the
  // place's lone assignment to hydrate & persist its times; with 0 or 2+
  // assignments the time is ambiguous and the modal hides the fields (#1247).
  const openPlaceEditor = useCallback((place: Place, preferredAssignmentId: number | null = null) => {
    if (!can('place_edit', trip)) return
    if (roadtripActive && (isServiceStopType(place.stop_type) || tripAccommodations.some(stay => stay.place_id === place.id)) && typeof place.lat === 'number' && typeof place.lng === 'number') {
      const visitId = preferredAssignmentId ?? resolvePoolAssignmentId(assignments, place.id)
      const entry = Object.entries(assignments).find(([, visits]) => visits.some(visit => visit.id === visitId))
      if (entry) {
        const dayId = Number(entry[0])
        const visit = entry[1].find(visit => visit.id === visitId)!
        const stay = tripAccommodations.find(stay => stay.place_id === place.id && stay.start_day_id === dayId)
        const category = place.stop_type ?? (stay ? 'hotel' : '')
        const routedDay = roadtripRoutes.days.find(day => day.stops.some(stop => stop.assignmentId === visitId))
        const arrivalTime = routedDay?.schedule.entries[routedDay.stops.findIndex(stop => stop.assignmentId === visitId)]?.arrival ?? null
        setStopDraft({
          poi: { osm_id: place.osm_id ?? '', name: place.name, lat: place.lat, lng: place.lng, category, poi_type: category, address: place.address ?? null, website: place.website ?? null, phone: place.phone ?? null, opening_hours: null, cuisine: null, source: 'trek', offRouteKm: 0, alongKm: 0 },
          arrivalTime, dayId, dayNumber: days.find(day => day.id === dayId)?.day_number ?? 0, position: visit.order_index ?? 0,
          editing: { placeId: place.id, stopType: place.stop_type ?? (stay ? 'hotel' : null), dwellMinutes: place.duration_minutes ?? 30, accommodationId: stay?.id, checkIn: stay?.check_in ?? '', checkOut: stay?.check_out ?? '' },
          ...(isOvernightCategory(category) ? { overnight: { ...overnightOptions(dayId), ...(stay ? { defaultEndDayId: stay.end_day_id } : {}) } } : {}),
        })
        return
      }
    }
    setEditingPlace(place)
    setEditingAssignmentId(preferredAssignmentId ?? resolvePoolAssignmentId(assignments, place.id))
    setPlaceFormDayId(null)
    setServiceStopForm(false)
    setShowPlaceForm(true)
  }, [can, trip, assignments, roadtripActive, tripAccommodations, days, overnightOptions, roadtripRoutes.days])

  /**
   * How long the drive stands here, for every stop alike.
   *
   * A booked night used to be sent to the booking form instead, because its duration was
   * read off the check-out and there was nothing here to set. The drive no longer reads
   * a check-out at all: a night is a stop that takes as long as it takes, and asking how
   * long is the same question at a hotel as at a viewpoint.
   */
  const editRoadtripStay = useCallback((draft: NonNullable<typeof stayDraft>) => {
    setStayDraft(draft)
  }, [])

  const handleDeletePlace = useCallback((placeId) => {
    if (!can('place_edit', trip)) return
    setDeletePlaceId(placeId)
  }, [can, trip])

  const confirmDeletePlace = useCallback(async () => {
    if (!deletePlaceId) return
    const state = useTripStore.getState()
    const capturedPlace = state.places.find(p => p.id === deletePlaceId)
    const capturedAssignments = Object.entries(state.assignments).flatMap(([dayId, as]) =>
      as.filter(a => a.place?.id === deletePlaceId).map(a => ({ dayId: Number(dayId), orderIndex: a.order_index }))
    )
    try {
      await tripActions.deletePlace(tripId, deletePlaceId)
      if (selectedPlaceId === deletePlaceId) setSelectedPlaceId(null)
      updateRouteForDay(selectedDayId)
      toast.success(t('trip.toast.placeDeleted'))
      if (capturedPlace) {
        pushUndo(t('undo.deletePlace'), async () => {
          const newPlace = await tripActions.addPlace(tripId, {
            name: capturedPlace.name,
            description: capturedPlace.description,
            lat: capturedPlace.lat,
            lng: capturedPlace.lng,
            address: capturedPlace.address,
            category_id: capturedPlace.category_id,
            price: capturedPlace.price,
            // An undone track has to come back as a track, not a bare point.
            route_geometry: capturedPlace.route_geometry,
            route_color: capturedPlace.route_color,
          })
          for (const { dayId, orderIndex } of capturedAssignments) {
            await tripActions.assignPlaceToDay(tripId, dayId, newPlace.id, orderIndex)
          }
        })
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [deletePlaceId, tripId, toast, selectedPlaceId, selectedDayId, updateRouteForDay, pushUndo])

  const confirmDeletePlaces = useCallback(async (ids?: number[]) => {
    const targetIds = ids ?? deletePlaceIds
    if (!targetIds?.length) return
    const state = useTripStore.getState()
    const capturedPlaces = state.places.filter(p => targetIds.includes(p.id))
    const capturedAssignments = Object.entries(state.assignments).flatMap(([dayId, as]) =>
      as.filter(a => a.place?.id != null && targetIds.includes(a.place.id)).map(a => ({ dayId: Number(dayId), placeId: a.place!.id, orderIndex: a.order_index }))
    )
    try {
      await tripActions.deletePlacesMany(tripId, targetIds)
      if (selectedPlaceId != null && targetIds.includes(selectedPlaceId)) setSelectedPlaceId(null)
      if (!ids) setDeletePlaceIds(null)
      updateRouteForDay(selectedDayId)
      toast.success(t('trip.toast.placesDeleted', { count: capturedPlaces.length }))
      if (capturedPlaces.length > 0) {
        pushUndo(t('undo.deletePlaces'), async () => {
          for (const place of capturedPlaces) {
            const newPlace = await tripActions.addPlace(tripId, {
              name: place.name, description: place.description,
              lat: place.lat, lng: place.lng, address: place.address,
              category_id: place.category_id, price: place.price,
              route_geometry: place.route_geometry, route_color: place.route_color,
            })
            for (const a of capturedAssignments.filter(x => x.placeId === place.id)) {
              await tripActions.assignPlaceToDay(tripId, a.dayId, newPlace.id, a.orderIndex)
            }
          }
        })
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [deletePlaceIds, tripId, toast, selectedPlaceId, selectedDayId, updateRouteForDay, pushUndo])

  const confirmChangeCategory = useCallback(async (ids: number[], categoryId: number | null) => {
    if (!ids.length) return
    const state = useTripStore.getState()
    // Capture each place's prior category so undo can restore them per group.
    const captured = state.places.filter(p => ids.includes(p.id)).map(p => ({ id: p.id, prev: p.category_id ?? null }))
    try {
      await tripActions.updatePlacesMany(tripId, ids, { category_id: categoryId })
      toast.success(t('places.categoryChanged', { count: ids.length }))
      if (captured.length > 0) {
        pushUndo(t('undo.changeCategory'), async () => {
          // Group the captured ids by their prior category so each set is restored
          // in one call ('null' key = previously uncategorized). Map is shadowed by
          // the lucide icon import in this file, so use a plain object.
          const byPrev: Record<string, number[]> = {}
          for (const { id, prev } of captured) {
            const key = prev === null ? 'null' : String(prev)
            ;(byPrev[key] ??= []).push(id)
          }
          for (const [key, group] of Object.entries(byPrev)) {
            await tripActions.updatePlacesMany(tripId, group, { category_id: key === 'null' ? null : Number(key) })
          }
        })
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [tripId, toast, pushUndo])

  const handleAssignToDay = useCallback(async (placeId: number, dayId?: number, position?: number) => {
    const target = dayId || selectedDayId
    if (!target) { toast.error(t('trip.toast.selectDay')); return }
    const place = places.find(p => p.id === placeId)
    // A place with a start of its own is drawn by it, so it is stored there too, the
    // way a stop moved over from another day is. Without one it goes where it was put.
    const slot = timedSlot(storedAssignments[String(target)] ?? [], tripAccommodations, place?.place_time, position) ?? position
    const plan = viasAfterInsert(target, slot, place)
    try {
      const assignment = await tripActions.assignPlaceToDay(tripId, target, placeId, slot)
      toast.success(t('trip.toast.assignedToDay'))
      if (plan) await roadtripVias.reanchor(target, plan)
      updateRouteForDay(target)
      if (assignment?.id) {
        const capturedAssignmentId = assignment.id
        const capturedTarget = target
        pushUndo(t('undo.assignPlace'), async () => {
          await tripActions.removeAssignment(tripId, capturedTarget, capturedAssignmentId)
        })
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [selectedDayId, tripId, toast, updateRouteForDay, pushUndo, t, places, storedAssignments, tripAccommodations, roadtripVias, viasAfterInsert])

  /**
   * Moves a stop from the day list onto another day, at a row of that day or at its
   * end without one.
   *
   * It can land in the middle of a day whose road has been drawn, on the row it was
   * dropped on or among the stops its start falls between. The vias of that day count
   * stops, so every one behind the new stop would shape the leg before the one it was
   * drawn on. They are moved the way a place added to the day moves them. Rejects when
   * a write fails, so the list can say so and leave its undo out.
   */
  const handleMoveToDay = useCallback(async (assignmentId: number, fromDayId: number, toDayId: number, position?: number) => {
    const place = (storedAssignments[String(fromDayId)] ?? []).find(a => a.id === assignmentId)?.place
    const plan = viasAfterInsert(toDayId, position, place)
    await tripActions.moveAssignment(tripId, assignmentId, fromDayId, toDayId, position)
    if (plan) await roadtripVias.reanchor(toDayId, plan)
  }, [tripId, tripActions, storedAssignments, roadtripVias, viasAfterInsert])

  const handleRemoveAssignment = useCallback(async (dayId: number, assignmentId: number) => {
    const state = useTripStore.getState()
    const capturedAssignment = (state.assignments[String(dayId)] || []).find(a => a.id === assignmentId)
    const capturedPlaceId = capturedAssignment?.place?.id
    const capturedOrderIndex = capturedAssignment?.order_index ?? 0
    // Worked out before the delete, while the day still has the stop the vias
    // were measured against. `after_order_index` is a POSITION, so taking a stop
    // away moves the ground under every via that follows it: the anchors keep
    // their old numbers and the drive silently reverts to the road the traveller
    // steered it off, or bends a leg they never chose. This control is reachable
    // from the place inspector in both modes, and it was the one mutating path
    // that never corrected them.
    const stopsBefore = roadtripStopsOf(dayId)
    const removedAt = stopsBefore.findIndex(a => a.id === assignmentId)
    const plan = removedAt === -1
      ? null
      : reanchorAfterRemove(roadtripVias.byDay[dayId] ?? [], removedAt, stopsBefore.length)
    try {
      await tripActions.removeAssignment(tripId, dayId, assignmentId)
      if (plan) await roadtripVias.reanchor(dayId, plan)
      updateRouteForDay(dayId)
      if (capturedPlaceId != null) {
        const capturedDayId = dayId
        const capturedPos = capturedOrderIndex
        pushUndo(t('undo.removeAssignment'), async () => {
          await tripActions.assignPlaceToDay(tripId, capturedDayId, capturedPlaceId, capturedPos)
        })
      }
    }
    catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [tripId, toast, updateRouteForDay, pushUndo, t, roadtripVias, roadtripStopsOf])

  const handleReorder = useCallback((dayId: number, orderedIds: number[]) => {
    const prevIds = (useTripStore.getState().assignments[String(dayId)] || [])
      .slice().sort((a, b) => a.order_index - b.order_index).map(a => a.id)
    // The rail counts anchors over routable stops only, so the plan is built in
    // that space. A drag here hands a whole new ordering rather than one move,
    // and any permutation is possible — so the anchors follow the stop they were
    // pinned behind instead of being shifted arithmetically. Without this the
    // day's detours stayed on their old numbers and the drive quietly took a
    // different road, persisted and visible to every collaborator.
    const visible = new Set(orderedIds)
    let nextVisible = 0
    const completeOrder = prevIds.map(id => visible.has(id) ? orderedIds[nextVisible++] : id)
    const stopIdsBefore = roadtripStopsOf(dayId).map(a => a.id)
    const stopIdsAfter = completeOrder.filter(id => stopIdsBefore.includes(id))
    const plan = reanchorByStopOrder(roadtripVias.byDay[dayId] ?? [], stopIdsBefore, stopIdsAfter)
    try {
      tripActions.reorderAssignments(tripId, dayId, completeOrder)
        .then(async () => {
          if (plan.vias.length || plan.remove.length) await roadtripVias.reanchor(dayId, plan)
          const capturedDayId = dayId
          const capturedPrevIds = prevIds
          pushUndo(t('undo.reorder'), async () => {
            await tripActions.reorderAssignments(tripId, capturedDayId, capturedPrevIds)
          })
        })
        .catch(err => toast.error(err instanceof Error ? err.message : t('trip.toast.reorderError')))
      updateRouteForDay(dayId)
    }
    catch { toast.error(t('trip.toast.reorderError')) }
  }, [tripId, toast, pushUndo, updateRouteForDay, t, roadtripVias, roadtripStopsOf])

  const handleUpdateDayTitle = useCallback(async (dayId, title) => {
    try { await tripActions.updateDayTitle(tripId, dayId, title) }
    catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }, [tripId, toast])

  const handleReorderDays = useCallback((orderedIds: number[]) => {
    const prevIds = (useTripStore.getState().days || [])
      .slice().sort((a, b) => (a.day_number ?? 0) - (b.day_number ?? 0)).map(d => d.id)
    tripActions.reorderDays(tripId, orderedIds)
      .then(() => {
        pushUndo(t('dayplan.reorderUndo'), async () => {
          await tripActions.reorderDays(tripId, prevIds)
        })
      })
      .catch(err => toast.error(err instanceof Error ? err.message : t('dayplan.reorderError')))
  }, [tripId, toast, pushUndo])

  const handleAddDay = useCallback((position?: number) => {
    tripActions.insertDay(tripId, position)
      .catch(err => toast.error(err instanceof Error ? err.message : t('dayplan.addDayError')))
  }, [tripId, toast])

  const handleSaveReservation = async (data: Record<string, string | number | null> & { title: string }) => {
    try {
      // Imported hotel with a reviewed address but no existing place picked: match
      // an existing place by name, else geocode the address and create one, then link it.
      const acc = (data as Record<string, any>).create_accommodation
      if (data.type === 'hotel' && acc && acc.venue && !acc.place_id) {
        acc.place_id = (await resolveImportedPlace(acc.venue)) ?? undefined
        delete acc.venue
      }
      // A hotel's address lives on the linked place. Write an edited address
      // through to it, otherwise the typed value was silently dropped and the
      // old one reappeared on the next open (#1496).
      if (data.type === 'hotel' && acc && typeof acc.address === 'string') {
        const address = acc.address.trim()
        const linkedPlace = acc.place_id ? places.find(p => p.id === Number(acc.place_id)) : undefined
        if (address && linkedPlace && (linkedPlace.address || '') !== address) {
          try { await tripActions.updatePlace(tripId, linkedPlace.id, { address }) }
          catch { /* keep saving the booking; the address still lands in location */ }
        }
        delete acc.address
      }
      if (editingReservation) {
        // Don't force a day here. The old code pinned it to the (often empty)
        // selected day, which dropped the booking out of the Plan; preserving the
        // old day_id instead left it stale when the date changed. Omitting it lets
        // the server derive the day from the booking's date, or keep the current
        // one when there is no date.
        const r = await tripActions.updateReservation(tripId, editingReservation.id, data)
        toast.success(t('trip.toast.reservationUpdated'))
        setShowReservationModal(false)
        setEditingReservation(null)
        if (data.type === 'hotel') {
          accommodationsApi.list(tripId).then(d => setTripAccommodations(d.accommodations || [])).catch(() => {})
        }
        return r
      } else {
        const r = await tripActions.addReservation(tripId, { ...data, day_id: selectedDayId || null })
        toast.success(t('trip.toast.reservationAdded'))
        setShowReservationModal(false)
        // An imported booking auto-creates a linked cost server-side; the saving client gets
        // no budget:created echo, so refresh the budget items here to surface it without a reload.
        if ((data as Record<string, unknown>).create_budget_entry) await tripActions.loadBudgetItems?.(tripId)
        // Refresh accommodations if hotel was created
        if (data.type === 'hotel') {
          accommodationsApi.list(tripId).then(d => setTripAccommodations(d.accommodations || [])).catch(() => {})
        }
        return r
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }

  const handleSaveTransport = async (data: Record<string, any> & { title: string }) => {
    try {
      if (editingTransport) {
        const r = await tripActions.updateReservation(tripId, editingTransport.id, data)
        toast.success(t('trip.toast.reservationUpdated'))
        setShowTransportModal(false)
        setEditingTransport(null)
        setTransportModalDayId(null)
        return r
      } else {
        const r = await tripActions.addReservation(tripId, data)
        toast.success(t('trip.toast.reservationAdded'))
        setShowTransportModal(false)
        setEditingTransport(null)
        setTransportModalDayId(null)
        // Surface the auto-created linked cost without a reload (no budget:created echo to us).
        if (data.create_budget_entry) await tripActions.loadBudgetItems?.(tripId)
        return r
      }
    } catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }

  const handleDeleteReservation = async (id) => {
    try {
      await tripActions.deleteReservation(tripId, id)
      toast.success(t('trip.toast.deleted'))
      // Refresh accommodations in case a hotel booking was deleted
      accommodationsApi.list(tripId).then(d => setTripAccommodations(d.accommodations || [])).catch(() => {})
    }
    catch (err: unknown) { toast.error(err instanceof Error ? err.message : t('common.unknownError')) }
  }

  // ── Review-before-save booking import ───────────────────────────────────────
  // Match an existing trip place by name, else geocode the reviewed address and
  // create one. Returns the place id (or null if even creation failed).
  const resolveImportedPlace = async (venue: { name?: string; address?: string | null }): Promise<number | null> => {
    const name = (venue.name || '').trim()
    const n = name.toLowerCase()
    if (n) {
      const existing = places.find(p => p.name?.trim().toLowerCase() === n)
        ?? places.find(p => p.name && (p.name.toLowerCase().includes(n) || n.includes(p.name.toLowerCase())))
      // Only a server-side id may be linked. A negative id is an offline temp id
      // (mutationQueue.nextTempId): the reservation write is online-only, the queue
      // rewrites temp ids in a URL but never inside another entity's body, and
      // day_accommodations.place_id carries a foreign key — so a temp id here is a
      // rolled-back insert and a 500 instead of a saved booking.
      if (existing && existing.id > 0) return existing.id
    }
    // Offline the booking itself cannot be written (reservations are online-only),
    // so minting a place here would only leave an orphan behind on the next flush
    // — and its temp id could never be linked anyway. Link nothing, and skip the
    // geocode round-trip too; the retry online matches this venue by name.
    if (isEffectivelyOffline()) return null
    let lat: number | null = null
    let lng: number | null = null
    let address: string | null = venue.address ?? null
    try {
      const query = venue.address ? `${name} ${venue.address}`.trim() : name
      if (query) {
        const res = await mapsApi.search(query)
        const hit = res?.places?.[0] as { lat?: number; lng?: number; address?: string } | undefined
        if (hit && hit.lat != null && hit.lng != null) {
          lat = hit.lat; lng = hit.lng
          if (!address && hit.address) address = hit.address
        }
      }
    } catch { /* geocode failure is non-fatal — create the place without coords */ }
    try {
      // Through the store, not placesApi directly: the API answers { place },
      // and reading .id off that wrapper linked nothing — every save of the
      // hotel then minted another orphan place, because the store never
      // learned about the previous one and the name match above could not
      // find it. addPlace unwraps the response and puts the place into
      // `places`, so the next save reuses it.
      const place = await tripActions.addPlace(tripId, { name: name || address || 'Accommodation', lat, lng, address })
      return place && place.id > 0 ? place.id : null
    } catch { return null }
  }

  // Open the right edit modal for a parsed item, pre-filled, in create mode.
  //
  // A type neither form can express belongs to whichever tab the user started from.
  // Handing an unreadable transport document to the booking form is what left them
  // with six chips, none of them a transport, and 'other' as the only honest pick
  // (#2076). A type either form DOES know always wins over the tab — one PDF
  // routinely holds a flight and a hotel.
  const openImportItem = (item: BookingImportPreviewItem) => {
    const draft = parsedItemToDraft(item)
    // Attach the file this item was parsed from so it lands in the booking's Files on save.
    const srcName = item.source?.fileName
    const srcFile = srcName ? importSourceFilesRef.current.find(f => f.name === srcName) : undefined
    if (srcFile) draft._sourceFiles = [srcFile]
    if (isTransportItem(item) || (isUnplaceableItem(item) && importKindRef.current === 'transports')) {
      setShowReservationModal(false); setEditingReservation(null); setReservationPrefill(null)
      setEditingTransport(null); setTransportModalDayId(null)
      setTransportPrefill(draft); setShowTransportModal(true)
    } else {
      setShowTransportModal(false); setEditingTransport(null); setTransportPrefill(null); setTransportModalDayId(null)
      setEditingReservation(null)
      setReservationPrefill(draft); setShowReservationModal(true)
    }
  }

  const startImportReview = (
    items: BookingImportPreviewItem[],
    sourceFiles: File[] = [],
    kind: 'transports' | 'bookings' = 'bookings',
  ) => {
    if (!items.length) return
    importSourceFilesRef.current = sourceFiles
    importKindRef.current = kind
    importQueueRef.current = items.slice(1)
    setImportReviewActive(true)
    openImportItem(items[0])
  }

  // Bridge: when a finished background import is sent here for review (the user hit
  // "review" in the background widget, on this or any page), open the per-item flow.
  // Lives in the hook so the page stays a pure wiring container.
  const bgTasks = useBackgroundTasksStore((s) => s.tasks)
  const dismissBgTask = useBackgroundTasksStore((s) => s.dismiss)
  useEffect(() => {
    const task = bgTasks.find(
      (tk) => tk.tripId === String(tripId) && tk.status === 'done' && tk.reviewRequested && !tk.consumed,
    )
    if (task && task.items && task.items.length > 0) {
      // Hand the items (and the source files, to attach to each booking) to the review flow
      // and clear the widget entry — once the user hit "review", the background card is done.
      const items = task.items
      const jobId = task.id
      const inMemory = task.sourceFiles
      const kind = task.kind ?? 'bookings'
      dismissBgTask(jobId)
      // Prefer the in-memory files (immediate path); after a reload they live in IndexedDB.
      void (async () => {
        const files = inMemory && inMemory.length ? inMemory : await getImportFiles(jobId)
        deleteImportFiles(jobId)
        startImportReview(items, files, kind)
      })()
    }
  }, [bgTasks, tripId, startImportReview, dismissBgTask])

  // Called when a reviewed item's modal closes (saved or skipped): open the next,
  // or finish the review session and refresh accommodations.
  const advanceImportReview = () => {
    const queue = importQueueRef.current
    if (queue.length > 0) {
      importQueueRef.current = queue.slice(1)
      openImportItem(queue[0])
      return
    }
    importQueueRef.current = []
    setImportReviewActive(false)
    setShowReservationModal(false); setEditingReservation(null); setReservationPrefill(null)
    setShowTransportModal(false); setEditingTransport(null); setTransportPrefill(null); setTransportModalDayId(null)
    accommodationsApi.list(tripId).then(d => setTripAccommodations(d.accommodations || [])).catch(() => {})
    // Imported bookings auto-create their linked costs server-side, but the saving client
    // suppresses its own budget:created echo (X-Socket-Id) — so reload the budget items here
    // to surface those expenses without a manual page refresh.
    tripActions.loadBudgetItems?.(tripId)
  }

  const selectedPlace = selectedPlaceId ? places.find(p => p.id === selectedPlaceId) : null
  // The stops the inspector speaks for. A booked night at a day's edge stands on the
  // hotel's place without being a stop of the day, so it is left out: counted, the hotel's
  // own stop lost its stay and its day end to a second match.
  const selectedRoadtripStops = roadtripRoutes.days.flatMap(day => day.stops).filter(stop =>
    !stop.automaticNight && !stop.bookend && (selectedAssignmentId ? stop.assignmentId === selectedAssignmentId : stop.placeId === selectedPlaceId),
  )
  const endDayStop = selectedRoadtripStops.length === 1 ? selectedRoadtripStops[0] : undefined
  const roadtripEndDay = roadtripActive && dailyTimesActive && can('day_edit', trip) && endDayStop && endDayStop.assignmentId > 0
    ? { active: roadtripEndsDayAt(endDayStop), onToggle: () => setRoadtripEndDay(endDayStop) }
    : undefined
  const roadtripStay = roadtripActive && selectedPlace
    ? inspectorStay(roadtripRoutes.days, endDayStop, selectedPlace, can('place_edit', trip) ? editRoadtripStay : undefined)
    : undefined

  // Build placeId → order-number map from the selected day's assignments. A service
  // stop is passed over rather than counted: the map draws it without a badge and the
  // rail gives it no number, so a number spent on it left the pin after a fuel stop
  // wearing "3" where the rail said "2".
  const dayOrderMap = useMemo(() => {
    if (!selectedDayId) return {}
    const da = assignments[String(selectedDayId)] || []
    const sorted = [...da].sort((a, b) => a.order_index - b.order_index)
    const map = {}
    let counted = 0
    sorted.forEach(a => {
      if (!a.place?.id || isServiceStopType(a.place.stop_type)) return
      counted += 1
      if (!map[a.place.id]) map[a.place.id] = []
      map[a.place.id].push(counted)
    })
    return map
  }, [selectedDayId, assignments])

  // Places assigned to selected day (with coords) — used for map fitting
  const dayPlaces = useMemo(() => {
    if (!selectedDayId) return []
    const da = assignments[String(selectedDayId)] || []
    return da.map(a => a.place).filter(p => p?.lat && p?.lng)
  }, [selectedDayId, assignments])

  const mapTileUrl = useTileUrl(OFM_POSITRON)

  const fontStyle = { fontFamily: "var(--font-system)" }

  // Splash screen — show for initial load + a brief moment for photos to start loading
  const [splashDone, setSplashDone] = useState(false)
  useEffect(() => {
    if (!isLoading && trip) {
      const timer = setTimeout(() => setSplashDone(true), 1500)
      return () => clearTimeout(timer)
    }
  }, [isLoading, trip])

  return {
    tripId, navigate, toast, t, language, locale, settings, placesPhotosEnabled,
    trip, days, places, assignments, storedAssignments, packingItems, todoItems, categories, reservations, budgetItems, files,
    selectedDayId, isLoading, tripActions, can, canUploadFiles,
    pushUndo, undo, canUndo, lastActionLabel, handleUndo,
    enabledAddons, collabFeatures, tripAccommodations, setTripAccommodations,
    roadtripMode, toggleRoadtripMode, roadtripActive, roadtripFeedActive, roadtripRoutes, roadtripLineColors, roadtripMapLines, roadtripMapPlaces, collapsedRoadtripDays, toggleRoadtripDay, roadtripCorridor,
    overviewShown, toggleOverview, overviewActive, tripOverview,
    dawarichTrailShown, toggleDawarichTrail, dawarichTrail, dawarichHiddenDates, dawarichEnabled: !!enabledAddons.dawarich,
    followTrack, roadtripViaCounts,
    allowedFileTypes, tripMembers, setTripMembers, refreshMembers, loadAccommodations,
    TRANSPORT_TYPES, TRIP_TABS, activeTab, setActiveTab, handleTabChange,
    leftWidth, rightWidth, leftCollapsed, rightCollapsed, setLeftCollapsed, setRightCollapsed,
    leftHidden, rightHidden, toggleLeft, toggleRight, narrowPanels,
    startResizeLeft, startResizeRight,
    selectedPlaceId, selectedAssignmentId, setSelectedPlaceId, selectAssignment,
    showDayDetail, setShowDayDetail, dayDetailCollapsed, setDayDetailCollapsed,
    showPlaceForm, setShowPlaceForm, editingPlace, setEditingPlace,
    prefillCoords, setPrefillCoords, editingAssignmentId, setEditingAssignmentId,
    placeFormDayId, setPlaceFormDayId, reservationModalDayId, setReservationModalDayId,
    stopDraft, setStopDraft, saveStopDraft, saveStopDraftAsNight, stopDraftToForm, stopDraftDuplicate, reorderRoadtripStop,
    stayRelease, setStayRelease, confirmStayRelease,
    setRoadtripStopKind,
    setRoadtripStopFill,
    roadtripEndsDayAt,
    roadtripSettingsLoading: !roadtripPreferencesState.ready && !roadtripPreferencesState.failed,
    saveRoadtripLimit: roadtripPreferencesState.ready && can('day_edit', trip) ? saveRoadtripLimit : undefined,
    roadtripVias, addRoadtripVia, moveRoadtripVia, removeRoadtripVia, dayBoundaryControls, resetDayBoundaries,
    manualStopTargetFor, openManualRoadtripStop, serviceStopMode, setServiceStopForm,
    refuel, askRefuel, acceptRefuel,
    routeAlternatives, askRouteAlternatives, chooseRouteAlternative, alternativeOverlays, alternativeFocusPoints, mapFocusPoints, roadtripMapVias, focusRoadtripPoint,
    stayDraft, setStayDraft, editRoadtripStay, setRoadtripStay, roadtripEndDay, roadtripStay,
    // Addressed by stop rather than by selection: the phone's stage sheet knows which
    // stop it is showing, and going through the place selection there would open the
    // permanently mounted place inspector underneath it.
    setRoadtripEndDay, dailyTimesActive,
    highlightedAlternative, setHighlightedAlternative,
    moveRoadtripStopToDay,
    dropPoiOnRoute,
    showTripForm, setShowTripForm, showMembersModal, setShowMembersModal,
    showReservationModal, setShowReservationModal, editingReservation, setEditingReservation,
    showBookingImport, setShowBookingImport, bookingImportKind, setBookingImportKind, bookingImportAvailable,
    airTrailAvailable, showAirTrailImport, setShowAirTrailImport,
    bookingForAssignmentId, setBookingForAssignmentId,
    showTransportModal, setShowTransportModal, editingTransport, setEditingTransport,
    transportModalDayId, setTransportModalDayId,
    transportModalAutomated, setTransportModalAutomated, transitPrefill, setTransitPrefill, transitJourney, setTransitJourney,
    reservationPrefill, transportPrefill, importReviewActive, startImportReview, advanceImportReview,
    routeShown, setRouteShown, autoShowRoute, transitRoutesShown, routeProfile, setRouteProfile, routeVias, fitKey, setFitKey,
    mobileSidebarOpen, setMobileSidebarOpen, mobilePlanScrollTopRef, mobilePlacesScrollTopRef,
    deletePlaceId, setDeletePlaceId, deletePlaceIds, setDeletePlaceIds, deletePlaceNote, deletePlacesNote,
    visibleConnections, roadtripConnections, toggleConnection, allConnectionsShown, toggleAllConnections, mapTransportDetail, setMapTransportDetail,
    isMobile, isTouch,
    expandedDayIds, setExpandedDayIds, mapPlaces,
    route, routeSegments, routeInfo, setRoute, setRouteInfo, updateRouteForDay,
    handleSelectDay, handlePlaceClick, handleMarkerClick, handleMapClick, handleMapContextMenu, openAddPlaceFromPoi, handlePoiClick,
    handleSavePlace, openPlaceEditor, handleDeletePlace, confirmDeletePlace, confirmDeletePlaces, confirmChangeCategory,
    handleAssignToDay, handleMoveToDay, handleRemoveAssignment, handleReorder, handleReorderDays, handleAddDay, handleUpdateDayTitle,
    handleSaveReservation, handleSaveTransport, handleDeleteReservation,
    selectedPlace, dayOrderMap, dayPlaces,
    mapTileUrl, fontStyle, splashDone,
  }
}