feat: 移植截图中心（浏览/分组/编辑/导出）

apps/app-frontend/src/composables/use-app-event.ts

@@ -0,0 +1,17 @@
+import { onUnmounted } from 'vue'
+
+import { instance_listener } from '@/helpers/events.js'
+
+export interface InstanceAppEvent {
+	event: string
+	instance_id?: string
+}
+
+export function useAppEvent(type: 'instance', callback: (event: InstanceAppEvent) => void) {
+	if (type !== 'instance') return
+	let unlisten: (() => void) | undefined
+	void instance_listener(callback).then((dispose) => {
+		unlisten = dispose
+	})
+	onUnmounted(() => unlisten?.())
+}

apps/app-frontend/src/composables/use-image-thumbnail.ts

@@ -0,0 +1,154 @@
+import { convertFileSrc, invoke } from '@tauri-apps/api/core'
+import { type MaybeRefOrGetter, ref, toValue, watch } from 'vue'
+
+export type ImageThumbnailSource = {
+	instanceId: string
+	filePath: string
+	path: string
+}
+
+type ThumbnailCacheEntry = {
+	promise: Promise<string>
+	url?: string
+	users: number
+	lastUsed: number
+}
+
+const MAX_CONCURRENT_THUMBNAILS = 4
+const MAX_CACHED_THUMBNAILS = 256
+
+const thumbnailCache = new Map<string, ThumbnailCacheEntry>()
+const thumbnailQueue: Array<() => void> = []
+let activeThumbnailRequests = 0
+
+function runThumbnailQueue() {
+	while (activeThumbnailRequests < MAX_CONCURRENT_THUMBNAILS && thumbnailQueue.length > 0) {
+		activeThumbnailRequests += 1
+		thumbnailQueue.shift()?.()
+	}
+}
+
+function enqueueThumbnail<T>(task: () => Promise<T>) {
+	return new Promise<T>((resolve, reject) => {
+		thumbnailQueue.push(() => {
+			void task()
+				.then(resolve, reject)
+				.finally(() => {
+					activeThumbnailRequests -= 1
+					runThumbnailQueue()
+				})
+		})
+		runThumbnailQueue()
+	})
+}
+
+function removeThumbnail(cacheKey: string, entry: ThumbnailCacheEntry) {
+	if (thumbnailCache.get(cacheKey) !== entry) return
+	thumbnailCache.delete(cacheKey)
+	if (entry.url) {
+		URL.revokeObjectURL(entry.url)
+	} else {
+		void entry.promise.then(
+			(url) => URL.revokeObjectURL(url),
+			() => undefined,
+		)
+	}
+}
+
+function trimThumbnailCache() {
+	if (thumbnailCache.size <= MAX_CACHED_THUMBNAILS) return
+
+	const unused = [...thumbnailCache.entries()]
+		.filter(([, entry]) => entry.users === 0)
+		.sort(([, left], [, right]) => left.lastUsed - right.lastUsed)
+	for (const [cacheKey, entry] of unused) {
+		if (thumbnailCache.size <= MAX_CACHED_THUMBNAILS) break
+		removeThumbnail(cacheKey, entry)
+	}
+}
+
+function acquireThumbnail(source: ImageThumbnailSource, maxDimension: number, revision: unknown) {
+	const cacheKey = JSON.stringify([
+		source.instanceId,
+		source.filePath,
+		maxDimension,
+		revision ?? null,
+	])
+	let entry = thumbnailCache.get(cacheKey)
+	if (!entry) {
+		entry = {
+			users: 0,
+			lastUsed: performance.now(),
+			promise: enqueueThumbnail(async () => {
+				const bytes = await invoke<ArrayBuffer>('plugin:files|screenshot_thumbnail', {
+					instanceId: source.instanceId,
+					filePath: source.filePath,
+					maxDimension,
+				})
+				return URL.createObjectURL(new Blob([bytes]))
+			}),
+		}
+		thumbnailCache.set(cacheKey, entry)
+		void entry.promise.then(
+			(url) => {
+				entry!.url = url
+				trimThumbnailCache()
+			},
+			() => {
+				if (thumbnailCache.get(cacheKey) === entry) thumbnailCache.delete(cacheKey)
+			},
+		)
+	}
+
+	entry.users += 1
+	entry.lastUsed = performance.now()
+	return {
+		promise: entry.promise,
+		release: () => {
+			entry!.users = Math.max(0, entry!.users - 1)
+			entry!.lastUsed = performance.now()
+			trimThumbnailCache()
+		},
+	}
+}
+
+export function useImageThumbnail(
+	source: MaybeRefOrGetter<ImageThumbnailSource | null | undefined>,
+	maxDimension: MaybeRefOrGetter<number> = 512,
+	revision: MaybeRefOrGetter<string | number | undefined> = undefined,
+) {
+	const thumbnail = ref('')
+
+	watch(
+		[() => toValue(source), () => toValue(maxDimension), () => toValue(revision)],
+		([currentSource, currentMaxDimension, currentRevision], _, onCleanup) => {
+			thumbnail.value = ''
+			if (!currentSource) return
+
+			let active = true
+			const fallbackUrl = convertFileSrc(currentSource.path)
+			const acquired = acquireThumbnail(
+				currentSource,
+				Math.max(1, Math.round(currentMaxDimension)),
+				currentRevision,
+			)
+			onCleanup(() => {
+				active = false
+				acquired.release()
+			})
+
+			void acquired.promise.then(
+				(url) => {
+					if (active) thumbnail.value = url
+				},
+				(error) => {
+					console.warn('Could not create image thumbnail', error)
+					if (active) thumbnail.value = fallbackUrl
+				},
+			)
+		},
+		{ immediate: true },
+	)
+
+	return thumbnail
+}