import { setupTest, startEngine, startClientInTmux, openCmdFifo, writeFifoCommand, wait, tmuxSendKeys, tmuxCapturePane, isProcessAlive, execSync, teardownTest } from './test_utils';

export async function testStressRandomUsage(): Promise<void> {
  console.log("\nTest: STRESS RANDOM USAGE (10,000 keys, stability check)");
  setupTest();
  const engine = await startEngine();
  await startClientInTmux();
  openCmdFifo();
  await wait(500);

  // Pre‑add channels for more variety
  for (let i = 0; i < 7; i++) {
    writeFifoCommand("add");
    await wait(100);
  }

  const KEY_ACTIONS = ['h','j','k','l','t','d','s','S','a','A','r','b','u'];
  const TOTAL = 5000;
  const KEY_DELAY_MS = 20;
  const CHECK_INTERVAL = 500;

  console.log(`  Starting stress loop: ${TOTAL} keys at ~20 keys/second...`);
  let keysSent = 0;
  const startTime = Date.now();

  for (let i = 0; i < TOTAL; i++) {
    const key = KEY_ACTIONS[Math.floor(Math.random() * KEY_ACTIONS.length)];
    tmuxSendKeys("looper", "0", key);
    await wait(KEY_DELAY_MS);
    keysSent++;

    if (keysSent % CHECK_INTERVAL === 0) {
      // Wait a little for TUI to settle
      await wait(500);

      // Check engine alive
      if (engine.pid && !isProcessAlive(engine.pid)) {
        console.log(`  FAIL: Engine died at key ${keysSent}`);
        try {
          const stderr = execSync("tail -20 /tmp/engine_stderr.log", { encoding: "utf-8" }).trim();
          console.log("  Engine stderr:", stderr);
        } catch {}
        teardownTest();
        throw new Error("Engine crash during stress test");
      }

      // Wait a little more for TUI to settle and pane to be captured fully
      await wait(1000);

      // Retry pane capture up to 5 times with small delays if it doesn't contain "Selected:"
      let pane = "";
      for (let retry = 0; retry < 5; retry++) {
        pane = tmuxCapturePane("looper", "0");
        if (pane && pane.includes("Selected:")) break;
        await wait(200);
        pane = tmuxCapturePane("looper", "0");
      }

      if (!pane || !pane.includes("Selected:")) {
        console.log(`  FAIL: TUI pane appears corrupted at key ${keysSent}`);
        console.log("  Pane:\n" + (pane ? pane.slice(0, 1000) : "(empty)"));
        teardownTest();
        throw new Error("TUI corruption during stress test");
      }
    }
  }

  const elapsed = ((Date.now() - startTime) / 1000).toFixed(1);
  console.log(`  Stress loop finished in ${elapsed}s`);

  await wait(500);
  if (engine.pid && !isProcessAlive(engine.pid)) {
    console.log("  FAIL: Engine died after test");
    teardownTest();
    throw new Error("Engine crash");
  }
  console.log("  PASS: Stress test completed (no crash or corruption)");
  engine.kill();
  teardownTest();
}