mirror of
https://github.com/mauriceboe/TREK.git
synced 2026-11-13 15:51:00 +00:00
Maurice
afaacec61a
The watch's snapshot was rebuilt every fifteen minutes, so a tick in the app or one arriving over the WebSocket did not reach the watch until then. It is now rebuilt as soon as the packing lists or the to-dos change in the offline tables. A tick on the watch goes as a message while the phone is in reach, which wakes the phone app, and a phone app in the background writes it to the server itself, so the trip's other devices hear of it at once instead of when the phone app is next opened.
43 lines
1.5 KiB
TypeScript
43 lines
1.5 KiB
TypeScript
import { liveQuery } from 'dexie';
|
|
import { offlineDb } from '../db/offlineDb';
|
|
|
|
/** Long enough to take a run of ticks (or a synced batch) as one change, short enough to read as instant. */
|
|
const SETTLE_MS = 300;
|
|
|
|
/**
|
|
* Calls `run` once the packing lists or the to-dos this device keeps offline
|
|
* have changed, after they settled: a tick in the app, a tick from the watch
|
|
* written through, or another member's tick arriving over the WebSocket (the
|
|
* remote event handler writes it to the same tables). The watch's snapshot is
|
|
* built from those tables, so this is what keeps the watch as current as the
|
|
* phone instead of waiting for the next quarter-hour refresh.
|
|
*
|
|
* The first answer of the query is the state at subscription, not a change, and
|
|
* is skipped. Returns the unsubscribe.
|
|
*/
|
|
export function onWatchListsChange(run: () => void, settleMs = SETTLE_MS): () => void {
|
|
let first = true;
|
|
let timer: ReturnType<typeof setTimeout> | null = null;
|
|
const subscription = liveQuery(() =>
|
|
Promise.all([offlineDb.packingItems.toArray(), offlineDb.todoItems.toArray()])
|
|
).subscribe({
|
|
next: () => {
|
|
if (first) {
|
|
first = false;
|
|
return;
|
|
}
|
|
if (timer) clearTimeout(timer);
|
|
timer = setTimeout(() => {
|
|
timer = null;
|
|
run();
|
|
}, settleMs);
|
|
},
|
|
// A failed read changes nothing on the watch; the next write tries again.
|
|
error: () => undefined,
|
|
});
|
|
return () => {
|
|
if (timer) clearTimeout(timer);
|
|
subscription.unsubscribe();
|
|
};
|
|
}
|