feat(overlay): run session help commands with Enter or double-click (#275)

src/renderer/utils/mpv-command-dispatch.test.ts

@@ -0,0 +1,58 @@
+import assert from 'node:assert/strict';
+import test from 'node:test';
+
+import { dispatchConfiguredMpvCommand } from './mpv-command-dispatch';
+
+async function dispatch(command: (string | number)[], paused: boolean | null | Error) {
+  const sent: (string | number)[][] = [];
+  dispatchConfiguredMpvCommand(command, {
+    getPlaybackPaused: async () => {
+      if (paused instanceof Error) throw paused;
+      return paused;
+    },
+    sendMpvCommand: (mpvCommand) => sent.push(mpvCommand),
+  });
+  await new Promise((resolve) => setTimeout(resolve, 0));
+  return sent;
+}
+
+test('subtitle seeks keep paused or unknown playback paused', async () => {
+  const repaused = [
+    ['sub-seek', 1],
+    ['set_property', 'pause', 'yes'],
+  ];
+  assert.deepEqual(await dispatch(['sub-seek', 1], true), repaused);
+  assert.deepEqual(await dispatch(['sub-seek', 1], null), repaused);
+});
+
+test('subtitle seeks leave running playback alone', async () => {
+  assert.deepEqual(await dispatch(['sub-seek', -1], false), [['sub-seek', -1]]);
+  assert.deepEqual(await dispatch(['sub-seek', -1], new Error('ipc down')), [['sub-seek', -1]]);
+});
+
+test('other mpv commands are sent as-is', async () => {
+  assert.deepEqual(await dispatch(['cycle', 'pause'], true), [['cycle', 'pause']]);
+});
+
+test('a failed re-pause does not resend the subtitle seek', async () => {
+  const sent: (string | number)[][] = [];
+  const originalConsoleError = console.error;
+  console.error = () => {};
+  try {
+    dispatchConfiguredMpvCommand(['sub-seek', 1], {
+      getPlaybackPaused: async () => true,
+      sendMpvCommand: (command) => {
+        sent.push(command);
+        if (command[0] === 'set_property') throw new Error('ipc closed');
+      },
+    });
+    await new Promise((resolve) => setTimeout(resolve, 0));
+  } finally {
+    console.error = originalConsoleError;
+  }
+
+  assert.deepEqual(sent, [
+    ['sub-seek', 1],
+    ['set_property', 'pause', 'yes'],
+  ]);
+});

src/renderer/utils/mpv-command-dispatch.ts

@@ -0,0 +1,38 @@
+type MpvCommand = (string | number)[];
+
+function isSubtitleSeekCommand(command: MpvCommand): command is [string, number] {
+  return command[0] === 'sub-seek' && typeof command[1] === 'number';
+}
+
+/**
+ * Sends a configured mpv command. Subtitle seeks re-pause afterwards unless playback
+ * is known to be running, so stepping lines from a paused video stays paused.
+ */
+export function dispatchConfiguredMpvCommand(
+  command: MpvCommand,
+  deps: {
+    getPlaybackPaused: () => Promise<boolean | null>;
+    sendMpvCommand: (command: MpvCommand) => void;
+  },
+): void {
+  if (!isSubtitleSeekCommand(command)) {
+    deps.sendMpvCommand(command);
+    return;
+  }
+
+  // The fallback only covers a failed pause lookup, so a failed re-pause never resends the seek.
+  void deps
+    .getPlaybackPaused()
+    .then(
+      (paused) => {
+        deps.sendMpvCommand(command);
+        if (paused !== false) {
+          deps.sendMpvCommand(['set_property', 'pause', 'yes']);
+        }
+      },
+      () => {
+        deps.sendMpvCommand(command);
+      },
+    )
+    .catch((error: unknown) => console.error('Could not send mpv command', error));
+}