Convert the whole filesystem UI to Typescript

svelte/src/lib/VideoPosition.ts

@@ -0,0 +1,105 @@
+
+type VideoPositions = {
+	[key: string]: VideoPosition
+}
+
+export type VideoPosition = {
+	time: number
+	pos: number
+	dur: number
+}
+
+const storage_key = "video_positions"
+const expiry_time = 28 * 24 * 60 * 60 * 1000
+
+let position_cache: VideoPositions | null = null
+export const get_video_positions = () => {
+	if (position_cache !== null) {
+		return position_cache
+	}
+
+	let video_positions = JSON.parse(window.localStorage.getItem(storage_key)) as VideoPositions
+	if (video_positions === null) {
+		return {} as VideoPositions
+	}
+	return video_positions
+}
+
+export const save_video_position = (id: string, position: number, duration: number) => {
+	if (duration < 300) {
+		return // Don't bother saving videos less than 5 minutes long
+	}
+
+	const video_positions = get_video_positions()
+
+	// Add our new entry
+	video_positions[id] = {
+		time: (new Date).getTime(),
+		pos: position,
+		dur: duration,
+	}
+
+	// Remove old entries
+	const expiry_thresh = (new Date).getTime() - expiry_time
+	for (const key in video_positions) {
+		if (video_positions[key].time < expiry_thresh) {
+			delete video_positions[key]
+			console.debug("Delete old video position", key)
+		}
+	}
+
+	// Save updated object
+	window.localStorage.setItem(storage_key, JSON.stringify(video_positions))
+
+	// Update the cache
+	position_cache = video_positions
+}
+
+export const get_video_position = (id: string) => {
+	const video_positions = get_video_positions()
+	if (video_positions[id] === undefined) {
+		return null
+	}
+	return video_positions[id]
+}
+
+export const video_position = (node: HTMLVideoElement, get_id: () => string) => {
+	let last_time = 0
+
+	const loadeddata = (e: Event) => {
+		last_time = 0
+
+		const vp = get_video_position(get_id())
+		if (vp === null || vp.pos === 0 || vp.dur === 0) {
+			return
+		} else if (vp.pos / vp.dur > 0.95) {
+			// If the video is more than 95% complete we don't do anything
+			console.debug("Video is at end, not setting time")
+			return
+		}
+
+		(e.target as HTMLVideoElement).currentTime = vp.pos
+		last_time = vp.pos
+	}
+
+	const timeupdate = (e: Event) => {
+		const vid = (e.target as HTMLVideoElement)
+
+		// If the current timestamp is more than ten seconds off the last
+		// timestamp we saved, then we save the new timestamp
+		if (Math.abs(vid.currentTime - last_time) > 10) {
+			save_video_position(get_id(), vid.currentTime, vid.duration)
+			last_time = vid.currentTime
+		}
+	}
+
+	node.addEventListener("loadeddata", loadeddata)
+	node.addEventListener("timeupdate", timeupdate)
+
+	return {
+		destroy() {
+			node.removeEventListener("loadeddata", loadeddata)
+			node.removeEventListener("timeupdate", timeupdate)
+		}
+	}
+}