import React, { useState, useEffect, useRef } from 'react'
import Modal from '../shared/Modal'
import { Calendar, Camera, X } from 'lucide-react'
import { tripsApi } from '../../api/client'
import { useToast } from '../shared/Toast'
import { useTranslation } from '../../i18n'
import { CustomDatePicker } from '../shared/CustomDateTimePicker'

export default function TripFormModal({ isOpen, onClose, onSave, trip, onCoverUpdate }) {
  const isEditing = !!trip
  const fileRef = useRef(null)
  const toast = useToast()
  const { t } = useTranslation()

  const [formData, setFormData] = useState({
    title: '',
    description: '',
    start_date: '',
    end_date: '',
  })
  const [error, setError] = useState('')
  const [isLoading, setIsLoading] = useState(false)
  const [coverPreview, setCoverPreview] = useState(null)
  const [uploadingCover, setUploadingCover] = useState(false)

  useEffect(() => {
    if (trip) {
      setFormData({
        title: trip.title || '',
        description: trip.description || '',
        start_date: trip.start_date || '',
        end_date: trip.end_date || '',
      })
      setCoverPreview(trip.cover_image || null)
    } else {
      setFormData({ title: '', description: '', start_date: '', end_date: '' })
      setCoverPreview(null)
    }
    setError('')
  }, [trip, isOpen])

  const handleSubmit = async (e) => {
    e.preventDefault()
    setError('')
    if (!formData.title.trim()) { setError(t('dashboard.titleRequired')); return }
    if (formData.start_date && formData.end_date && new Date(formData.end_date) < new Date(formData.start_date)) {
      setError(t('dashboard.endDateError')); return
    }
    setIsLoading(true)
    try {
      await onSave({
        title: formData.title.trim(),
        description: formData.description.trim() || null,
        start_date: formData.start_date || null,
        end_date: formData.end_date || null,
      })
      onClose()
    } catch (err) {
      setError(err.message || t('places.saveError'))
    } finally {
      setIsLoading(false)
    }
  }

  const handleCoverChange = async (e) => {
    const file = e.target.files?.[0]
    if (!file || !trip?.id) return
    setUploadingCover(true)
    try {
      const fd = new FormData()
      fd.append('cover', file)
      const data = await tripsApi.uploadCover(trip.id, fd)
      setCoverPreview(data.cover_image)
      onCoverUpdate?.(trip.id, data.cover_image)
      toast.success(t('dashboard.coverSaved'))
    } catch {
      toast.error(t('dashboard.coverUploadError'))
    } finally {
      setUploadingCover(false)
      e.target.value = ''
    }
  }

  const handleRemoveCover = async () => {
    if (!trip?.id) return
    try {
      await tripsApi.update(trip.id, { cover_image: null })
      setCoverPreview(null)
      onCoverUpdate?.(trip.id, null)
    } catch {
      toast.error(t('dashboard.coverRemoveError'))
    }
  }

  const update = (field, value) => setFormData(prev => ({ ...prev, [field]: value }))

  const inputCls = "w-full px-3 py-2.5 border border-slate-200 rounded-lg text-slate-900 placeholder-slate-400 focus:outline-none focus:ring-2 focus:ring-slate-300 focus:border-transparent text-sm"

  return (
    <Modal
      isOpen={isOpen}
      onClose={onClose}
      title={isEditing ? t('dashboard.editTrip') : t('dashboard.createTrip')}
      size="md"
      footer={
        <div className="flex gap-3 justify-end">
          <button type="button" onClick={onClose}
            className="px-4 py-2 text-sm text-slate-600 hover:text-slate-800 border border-slate-200 rounded-lg hover:bg-slate-50 transition-colors">
            {t('common.cancel')}
          </button>
          <button onClick={handleSubmit} disabled={isLoading}
            className="px-4 py-2 text-sm bg-slate-900 hover:bg-slate-700 disabled:bg-slate-400 text-white rounded-lg transition-colors flex items-center gap-2">
            {isLoading
              ? <><div className="w-4 h-4 border-2 border-white/30 border-t-white rounded-full animate-spin" />{t('common.saving')}</>
              : isEditing ? t('common.update') : t('dashboard.createTrip')}
          </button>
        </div>
      }
    >
      <form onSubmit={handleSubmit} className="space-y-4">
        {error && (
          <div className="p-3 bg-red-50 border border-red-200 rounded-lg text-sm text-red-600">{error}</div>
        )}

        {/* Cover image — only for existing trips */}
        {isEditing && (
          <div>
            <label className="block text-sm font-medium text-slate-700 mb-1.5">{t('dashboard.coverImage')}</label>
            <input ref={fileRef} type="file" accept="image/*" style={{ display: 'none' }} onChange={handleCoverChange} />
            {coverPreview ? (
              <div style={{ position: 'relative', borderRadius: 10, overflow: 'hidden', height: 130 }}>
                <img src={coverPreview} alt="" style={{ width: '100%', height: '100%', objectFit: 'cover' }} />
                <div style={{ position: 'absolute', bottom: 8, right: 8, display: 'flex', gap: 6 }}>
                  <button type="button" onClick={() => fileRef.current?.click()} disabled={uploadingCover}
                    style={{ display: 'flex', alignItems: 'center', gap: 4, padding: '5px 10px', borderRadius: 8, background: 'rgba(0,0,0,0.55)', border: 'none', color: 'white', fontSize: 11.5, fontWeight: 600, cursor: 'pointer', backdropFilter: 'blur(4px)' }}>
                    <Camera size={12} /> {uploadingCover ? t('common.uploading') : t('common.change')}
                  </button>
                  <button type="button" onClick={handleRemoveCover}
                    style={{ display: 'flex', alignItems: 'center', padding: '5px 8px', borderRadius: 8, background: 'rgba(0,0,0,0.55)', border: 'none', color: 'white', cursor: 'pointer', backdropFilter: 'blur(4px)' }}>
                    <X size={12} />
                  </button>
                </div>
              </div>
            ) : (
              <button type="button" onClick={() => fileRef.current?.click()} disabled={uploadingCover}
                style={{ width: '100%', padding: '18px', border: '2px dashed #e5e7eb', borderRadius: 10, background: 'none', cursor: 'pointer', display: 'flex', alignItems: 'center', justifyContent: 'center', gap: 6, fontSize: 13, color: '#9ca3af', fontFamily: 'inherit' }}
                onMouseEnter={e => { e.currentTarget.style.borderColor = '#d1d5db'; e.currentTarget.style.color = '#6b7280' }}
                onMouseLeave={e => { e.currentTarget.style.borderColor = '#e5e7eb'; e.currentTarget.style.color = '#9ca3af' }}>
                <Camera size={15} /> {uploadingCover ? t('common.uploading') : t('dashboard.addCoverImage')}
              </button>
            )}
          </div>
        )}

        <div>
          <label className="block text-sm font-medium text-slate-700 mb-1.5">
            {t('dashboard.tripTitle')} <span className="text-red-500">*</span>
          </label>
          <input type="text" value={formData.title} onChange={e => update('title', e.target.value)}
            required placeholder={t('dashboard.tripTitlePlaceholder')} className={inputCls} />
        </div>

        <div>
          <label className="block text-sm font-medium text-slate-700 mb-1.5">{t('dashboard.tripDescription')}</label>
          <textarea value={formData.description} onChange={e => update('description', e.target.value)}
            placeholder={t('dashboard.tripDescriptionPlaceholder')} rows={3}
            className={`${inputCls} resize-none`} />
        </div>

        <div className="grid grid-cols-2 gap-4">
          <div>
            <label className="block text-sm font-medium text-slate-700 mb-1.5">
              <Calendar className="inline w-4 h-4 mr-1" />{t('dashboard.startDate')}
            </label>
            <CustomDatePicker value={formData.start_date} onChange={v => update('start_date', v)} placeholder={t('dashboard.startDate')} />
          </div>
          <div>
            <label className="block text-sm font-medium text-slate-700 mb-1.5">
              <Calendar className="inline w-4 h-4 mr-1" />{t('dashboard.endDate')}
            </label>
            <CustomDatePicker value={formData.end_date} onChange={v => update('end_date', v)} placeholder={t('dashboard.endDate')} />
          </div>
        </div>

        {!formData.start_date && !formData.end_date && (
          <p className="text-xs text-slate-400 bg-slate-50 rounded-lg p-3">
            {t('dashboard.noDateHint')}
          </p>
        )}
      </form>
    </Modal>
  )
}