chore: refactoring and tests, splitting up files (#12495)

packages/app/src/context/global-sync/queue.ts

@@ -0,0 +1,83 @@
+type QueueInput = {
+  paused: () => boolean
+  bootstrap: () => Promise<void>
+  bootstrapInstance: (directory: string) => Promise<void> | void
+}
+
+export function createRefreshQueue(input: QueueInput) {
+  const queued = new Set<string>()
+  let root = false
+  let running = false
+  let timer: ReturnType<typeof setTimeout> | undefined
+
+  const tick = () => new Promise<void>((resolve) => setTimeout(resolve, 0))
+
+  const take = (count: number) => {
+    if (queued.size === 0) return [] as string[]
+    const items: string[] = []
+    for (const item of queued) {
+      queued.delete(item)
+      items.push(item)
+      if (items.length >= count) break
+    }
+    return items
+  }
+
+  const schedule = () => {
+    if (timer) return
+    timer = setTimeout(() => {
+      timer = undefined
+      void drain()
+    }, 0)
+  }
+
+  const push = (directory: string) => {
+    if (!directory) return
+    queued.add(directory)
+    if (input.paused()) return
+    schedule()
+  }
+
+  const refresh = () => {
+    root = true
+    if (input.paused()) return
+    schedule()
+  }
+
+  async function drain() {
+    if (running) return
+    running = true
+    try {
+      while (true) {
+        if (input.paused()) return
+        if (root) {
+          root = false
+          await input.bootstrap()
+          await tick()
+          continue
+        }
+        const dirs = take(2)
+        if (dirs.length === 0) return
+        await Promise.all(dirs.map((dir) => input.bootstrapInstance(dir)))
+        await tick()
+      }
+    } finally {
+      running = false
+      if (input.paused()) return
+      if (root || queued.size) schedule()
+    }
+  }
+
+  return {
+    push,
+    refresh,
+    clear(directory: string) {
+      queued.delete(directory)
+    },
+    dispose() {
+      if (!timer) return
+      clearTimeout(timer)
+      timer = undefined
+    },
+  }
+}