Import AITURK IDE 1.0.0-beta.1 from Hermes 63279301; preserve MIT license

apps/desktop/electron/stream-throttle.ts

@@ -0,0 +1,119 @@
+// Stream-aware background throttling for chat windows.
+//
+// Chat windows must paint the live transcript while blurred, occluded, or
+// minimized — but a static `backgroundThrottling: false` in webPreferences
+// costs far more than that feature needs: it pins the renderer's
+// `document.visibilityState` to 'visible' for the life of the window, which
+// turns every visibility-gated poll and clock tick in the renderer into an
+// always-on timer. An idle, hidden Hermes burned ~20% CPU forever.
+//
+// So throttling is a runtime dial instead: the renderers already report
+// "which chats are mid-turn" for the quit guard (`hermes:active-work`), and
+// this controller rides the merged edge of those reports. Any turn in flight →
+// every registered chat window gets `setBackgroundThrottling(false)`, exactly
+// the streaming behavior the static flag used to provide. All turns done →
+// after a short trailing delay (so tail flushes land at full cadence) Chromium's
+// default throttling returns and hidden windows go quiet.
+//
+// Pure and Electron-free (timers + the WebContents surface are injected) so it
+// can be unit-tested, mirroring session-windows.ts.
+
+/** How long after the last turn ends before throttling is restored. Covers the
+ * stream queue's final coalesced flush and the settle writes that trail a
+ * turn's completion, so re-throttling never strands a visible delta. */
+const RETHROTTLE_DELAY_MS = 5_000
+
+export interface ThrottleWindowLike {
+  isDestroyed(): boolean
+  webContents?: {
+    isDestroyed(): boolean
+    setBackgroundThrottling(allowed: boolean): void
+  } | null
+}
+
+interface TimersLike {
+  clearTimeout(handle: unknown): void
+  setTimeout(fn: () => void, ms: number): unknown
+}
+
+export interface StreamThrottle {
+  /** True while windows are currently unthrottled (streaming or trailing). */
+  isUnthrottled(): boolean
+  /** Track a chat window; applies the current state immediately and stops
+   * tracking on close. */
+  register(win: ThrottleWindowLike & { on?: (event: string, fn: () => void) => void }): void
+  /** Report whether any turn is in flight across all renderers. */
+  update(busy: boolean): void
+}
+
+export function createStreamThrottle(
+  timers: TimersLike = { clearTimeout: handle => clearTimeout(handle as never), setTimeout },
+  delayMs: number = RETHROTTLE_DELAY_MS
+): StreamThrottle {
+  const windows = new Set<ThrottleWindowLike>()
+  let unthrottled = false
+  let trailing: unknown = null
+
+  function apply(win: ThrottleWindowLike) {
+    if (win.isDestroyed()) {
+      windows.delete(win)
+
+      return
+    }
+
+    const contents = win.webContents
+
+    if (!contents || contents.isDestroyed()) {
+      return
+    }
+
+    try {
+      contents.setBackgroundThrottling(!unthrottled)
+    } catch {
+      // A window mid-teardown can throw; it's about to leave the set anyway.
+    }
+  }
+
+  function applyAll() {
+    for (const win of windows) {
+      apply(win)
+    }
+  }
+
+  return {
+    isUnthrottled: () => unthrottled,
+
+    register(win) {
+      windows.add(win)
+      win.on?.('closed', () => windows.delete(win))
+      apply(win)
+    },
+
+    update(busy) {
+      if (busy) {
+        if (trailing !== null) {
+          timers.clearTimeout(trailing)
+          trailing = null
+        }
+
+        if (!unthrottled) {
+          unthrottled = true
+          applyAll()
+        }
+
+        return
+      }
+
+      if (!unthrottled || trailing !== null) {
+        return
+      }
+
+      // Trailing edge: keep full cadence briefly so the final flush paints.
+      trailing = timers.setTimeout(() => {
+        trailing = null
+        unthrottled = false
+        applyAll()
+      }, delayMs)
+    }
+  }
+}