WIP

web/js/cache.js

@@ -0,0 +1,89 @@
+function load_events(damus) {
+	if (!('event_cache' in localStorage))
+		return {}
+	const cached = JSON.parse(localStorage.getItem('event_cache'))
+
+	return cached.reduce((obj, ev) => {
+		obj[ev.id] = ev
+		process_event(damus, ev)
+		return obj
+	}, {})
+}
+
+function load_cache(damus) {
+	damus.all_events = load_events(damus)
+	load_timelines(damus)
+}
+
+function save_cache(damus) {
+	save_events(damus)
+	save_timelines(damus)
+}
+
+function save_events(damus)
+{
+	const keys = Object.keys(damus.all_events)
+	const MAX_KINDS = {
+		1: 2000,
+		0: 2000,
+
+		6: 100,
+		4: 100,
+		5: 100,
+		7: 100,
+	}
+
+	let counts = {}
+
+	let cached = keys.map((key) => {
+		const ev = damus.all_events[key]
+		const {sig, pubkey, content, tags, kind, created_at, id} = ev
+		return {sig, pubkey, content, tags, kind, created_at, id}
+	})
+
+	cached.sort((a,b) => b.created_at - a.created_at)
+	cached = cached.reduce((cs, ev) => {
+		counts[ev.kind] = (counts[ev.kind] || 0)+1
+		if (counts[ev.kind] < MAX_KINDS[ev.kind])
+			cs.push(ev)
+		return cs
+	}, [])
+
+	log_debug('saving all events to local storage', cached.length)
+
+	localStorage.setItem('event_cache', JSON.stringify(cached))
+}
+
+function save_timelines(damus)
+{
+	const views = Object.keys(damus.views).reduce((obj, view_name) => {
+		const view = damus.views[view_name]
+		obj[view_name] = view.events.map(e => e.id).slice(0,100)
+		return obj
+	}, {})
+	localStorage.setItem('views', JSON.stringify(views))
+}
+
+function load_timelines(damus)
+{
+	if (!('views' in localStorage))
+		return
+	const stored_views = JSON.parse(localStorage.getItem('views'))
+	for (const view_name of Object.keys(damus.views)) {
+		const view = damus.views[view_name]
+		view.events = (stored_views[view_name] || []).reduce((evs, evid) => {
+			const ev = damus.all_events[evid]
+			if (ev) evs.push(ev)
+			return evs
+		}, [])
+	}
+}
+
+function schedule_save_events(damus)
+{
+	if (damus.save_timer)
+		clearTimeout(damus.save_timer)
+	damus.save_timer = setTimeout(save_cache.bind(null, damus), 3000)
+}
+
+