// Google Meet plugin module implements node host behavior.
import { spawn, spawnSync, type ChildProcess } from "node:child_process";
import { randomUUID } from "node:crypto";
import { setTimeout as sleep } from "node:timers/promises";
import {
  DEFAULT_GOOGLE_MEET_AUDIO_INPUT_COMMAND,
  DEFAULT_GOOGLE_MEET_AUDIO_OUTPUT_COMMAND,
} from "./config.js";
import {
  GOOGLE_MEET_SYSTEM_PROFILER_COMMAND,
  outputMentionsBlackHole2ch,
} from "./transports/chrome-audio-device.js";

type NodeBridgeSession = {
  id: string;
  url?: string;
  mode?: string;
  outputCommand: { command: string; args: string[] };
  input?: ChildProcess;
  output?: ChildProcess;
  chunks: Buffer[];
  waiters: Array<() => void>;
  closed: boolean;
  createdAt: string;
  lastInputAt?: string;
  lastOutputAt?: string;
  lastClearAt?: string;
  lastInputBytes: number;
  lastOutputBytes: number;
  closedAt?: string;
  clearCount: number;
};

const sessions = new Map<string, NodeBridgeSession>();

function readStringArray(value: unknown): string[] | undefined {
  if (!Array.isArray(value)) {
    return undefined;
  }
  const result = value.filter(
    (entry): entry is string => typeof entry === "string" && entry.length > 0,
  );
  return result.length > 0 ? result : undefined;
}

function asRecord(value: unknown): Record<string, unknown> {
  return value && typeof value === "object" && !Array.isArray(value)
    ? (value as Record<string, unknown>)
    : {};
}

function readString(value: unknown): string | undefined {
  return typeof value === "string" && value.length > 0 ? value : undefined;
}

function formatErrorMessage(error: unknown): string {
  return error instanceof Error ? error.message : String(error);
}

function readNumber(value: unknown, fallback: number): number {
  return typeof value === "number" && Number.isFinite(value) && value > 0 ? value : fallback;
}

function runCommandWithTimeout(argv: string[], timeoutMs: number) {
  const [command, ...args] = argv;
  if (!command) {
    throw new Error("command must not be empty");
  }
  const result = spawnSync(command, args, {
    encoding: "utf8",
    timeout: timeoutMs,
  });
  return {
    code: typeof result.status === "number" ? result.status : result.error ? 1 : 0,
    stdout: result.stdout ?? "",
    stderr: result.stderr ?? (result.error ? formatErrorMessage(result.error) : ""),
  };
}

function assertBlackHoleAvailable(timeoutMs: number) {
  if (process.platform !== "darwin") {
    throw new Error("Chrome Meet transport with blackhole-2ch audio is currently macOS-only");
  }
  const result = runCommandWithTimeout(
    [GOOGLE_MEET_SYSTEM_PROFILER_COMMAND, "SPAudioDataType"],
    timeoutMs,
  );
  const output = `${result.stdout}\n${result.stderr}`;
  if (result.code !== 0 || !outputMentionsBlackHole2ch(output)) {
    throw new Error("BlackHole 2ch audio device not found on the node.");
  }
}

function splitCommand(argv: string[]): { command: string; args: string[] } {
  const [command, ...args] = argv;
  if (!command) {
    throw new Error("audio command must not be empty");
  }
  return { command, args };
}

function wake(session: NodeBridgeSession) {
  const waiters = session.waiters.splice(0);
  for (const waiter of waiters) {
    waiter();
  }
}

function stopSession(session: NodeBridgeSession) {
  const wasClosed = session.closed;
  session.closed = true;
  session.closedAt ??= new Date().toISOString();
  terminateChild(session.input);
  terminateChild(session.output);
  if (!wasClosed) {
    wake(session);
  }
}

function attachOutputProcessHandlers(session: NodeBridgeSession, outputProcess: ChildProcess) {
  outputProcess.on("exit", () => {
    if (session.output === outputProcess) {
      stopSession(session);
    }
  });
  outputProcess.on("error", () => {
    if (session.output === outputProcess) {
      stopSession(session);
    }
  });
  outputProcess.stdin?.on?.("error", () => {
    if (session.output === outputProcess) {
      stopSession(session);
    }
  });
}

function startOutputProcess(command: { command: string; args: string[] }) {
  return spawn(command.command, command.args, {
    stdio: ["pipe", "ignore", "pipe"],
  });
}

function startCommandPair(params: {
  inputCommand: string[];
  outputCommand: string[];
  url?: string;
  mode?: string;
}): NodeBridgeSession {
  const input = splitCommand(params.inputCommand);
  const output = splitCommand(params.outputCommand);
  const session: NodeBridgeSession = {
    id: `meet_node_${randomUUID()}`,
    url: params.url,
    mode: params.mode,
    outputCommand: output,
    chunks: [],
    waiters: [],
    closed: false,
    createdAt: new Date().toISOString(),
    lastInputBytes: 0,
    lastOutputBytes: 0,
    clearCount: 0,
  };
  const outputProcess = startOutputProcess(output);
  const inputProcess = spawn(input.command, input.args, {
    stdio: ["ignore", "pipe", "pipe"],
  });
  session.input = inputProcess;
  session.output = outputProcess;
  inputProcess.stdout?.on("data", (chunk) => {
    const audio = Buffer.isBuffer(chunk) ? chunk : Buffer.from(chunk);
    session.lastInputAt = new Date().toISOString();
    session.lastInputBytes += audio.byteLength;
    session.chunks.push(audio);
    if (session.chunks.length > 200) {
      session.chunks.splice(0, session.chunks.length - 200);
    }
    wake(session);
  });
  inputProcess.on("exit", () => stopSession(session));
  attachOutputProcessHandlers(session, outputProcess);
  inputProcess.on("error", () => stopSession(session));
  sessions.set(session.id, session);
  return session;
}

function terminateChild(child?: ChildProcess) {
  if (!child) {
    return;
  }
  let exited = child.exitCode !== null || child.signalCode !== null;
  child.once?.("exit", () => {
    exited = true;
  });
  try {
    child.kill("SIGTERM");
  } catch {
    // Best-effort cleanup for node-host child processes.
  }
  const timer = setTimeout(() => {
    if (exited) {
      return;
    }
    try {
      child.kill("SIGKILL");
    } catch {
      // Process may have exited after the grace check.
    }
  }, 2_000);
  timer.unref?.();
}

async function pullAudio(params: Record<string, unknown>) {
  const bridgeId = readString(params.bridgeId);
  if (!bridgeId) {
    throw new Error("bridgeId required");
  }
  const session = sessions.get(bridgeId);
  if (!session) {
    throw new Error(`unknown bridgeId: ${bridgeId}`);
  }
  const timeoutMs = Math.min(readNumber(params.timeoutMs, 250), 2_000);
  if (session.chunks.length === 0 && !session.closed) {
    await Promise.race([
      sleep(timeoutMs),
      new Promise<void>((resolve) => {
        session.waiters.push(resolve);
      }),
    ]);
  }
  const chunk = session.chunks.shift();
  return {
    bridgeId,
    closed: session.closed,
    base64: chunk ? chunk.toString("base64") : undefined,
  };
}

function pushAudio(params: Record<string, unknown>) {
  const bridgeId = readString(params.bridgeId);
  const base64 = readString(params.base64);
  if (!bridgeId || !base64) {
    throw new Error("bridgeId and base64 required");
  }
  const session = sessions.get(bridgeId);
  if (!session || session.closed) {
    throw new Error(`bridge is not open: ${bridgeId}`);
  }
  const audio = Buffer.from(base64, "base64");
  session.lastOutputAt = new Date().toISOString();
  session.lastOutputBytes += audio.byteLength;
  try {
    session.output?.stdin?.write(audio);
  } catch {
    stopSession(session);
    throw new Error(`bridge is not open: ${bridgeId}`);
  }
  return { bridgeId, ok: true };
}

function clearAudio(params: Record<string, unknown>) {
  const bridgeId = readString(params.bridgeId);
  if (!bridgeId) {
    throw new Error("bridgeId required");
  }
  const session = sessions.get(bridgeId);
  if (!session || session.closed) {
    throw new Error(`bridge is not open: ${bridgeId}`);
  }
  const previousOutput = session.output;
  const outputProcess = startOutputProcess(session.outputCommand);
  session.output = outputProcess;
  attachOutputProcessHandlers(session, outputProcess);
  session.clearCount += 1;
  session.lastClearAt = new Date().toISOString();
  terminateChild(previousOutput);
  return { bridgeId, ok: true, clearCount: session.clearCount };
}

function startChrome(params: Record<string, unknown>) {
  const url = readString(params.url);
  if (!url) {
    throw new Error("url required");
  }
  const timeoutMs = readNumber(params.joinTimeoutMs, 30_000);
  const mode = readString(params.mode);

  let bridgeId: string | undefined;
  let audioBridge: { type: "external-command" | "node-command-pair" } | undefined;
  if (mode === "agent" || mode === "bidi" || mode === "realtime") {
    assertBlackHoleAvailable(Math.min(timeoutMs, 10_000));

    const healthCommand = readStringArray(params.audioBridgeHealthCommand);
    if (healthCommand) {
      const health = runCommandWithTimeout(healthCommand, timeoutMs);
      if (health.code !== 0) {
        throw new Error(
          `Chrome audio bridge health check failed: ${health.stderr || health.stdout || health.code}`,
        );
      }
    }

    const bridgeCommand = readStringArray(params.audioBridgeCommand);
    if (bridgeCommand) {
      if (mode === "agent") {
        throw new Error(
          "Chrome agent mode requires audioInputCommand and audioOutputCommand so OpenClaw can run STT and regular TTS directly.",
        );
      }
      const bridge = runCommandWithTimeout(bridgeCommand, timeoutMs);
      if (bridge.code !== 0) {
        throw new Error(
          `failed to start Chrome audio bridge: ${bridge.stderr || bridge.stdout || bridge.code}`,
        );
      }
      audioBridge = { type: "external-command" };
    } else {
      const session = startCommandPair({
        inputCommand: readStringArray(params.audioInputCommand) ?? [
          ...DEFAULT_GOOGLE_MEET_AUDIO_INPUT_COMMAND,
        ],
        outputCommand: readStringArray(params.audioOutputCommand) ?? [
          ...DEFAULT_GOOGLE_MEET_AUDIO_OUTPUT_COMMAND,
        ],
        url,
        mode,
      });
      bridgeId = session.id;
      audioBridge = { type: "node-command-pair" };
    }
  }

  if (params.launch !== false) {
    const argv = ["open", "-a", "Google Chrome"];
    const browserProfile = readString(params.browserProfile);
    if (browserProfile) {
      argv.push("--args", `--profile-directory=${browserProfile}`);
    }
    argv.push(url);
    const result = runCommandWithTimeout(argv, timeoutMs);
    if (result.code !== 0) {
      if (bridgeId) {
        const session = sessions.get(bridgeId);
        if (session) {
          stopSession(session);
        }
      }
      throw new Error(
        `failed to launch Chrome for Meet: ${result.stderr || result.stdout || result.code}`,
      );
    }
  }

  return {
    launched: params.launch !== false,
    bridgeId,
    audioBridge,
    browser:
      params.launch !== false
        ? {
            status: "chrome-opened",
            browserUrl: url,
            notes: [
              "Browser page control is handled by OpenClaw browser automation when using chrome-node.",
            ],
          }
        : undefined,
  };
}

function bridgeStatus(params: Record<string, unknown>) {
  const bridgeId = readString(params.bridgeId);
  const session = bridgeId ? sessions.get(bridgeId) : undefined;
  return {
    bridge: session
      ? {
          bridgeId,
          closed: session.closed,
          createdAt: session.createdAt,
          lastInputAt: session.lastInputAt,
          lastOutputAt: session.lastOutputAt,
          lastClearAt: session.lastClearAt,
          lastInputBytes: session.lastInputBytes,
          lastOutputBytes: session.lastOutputBytes,
          clearCount: session.clearCount,
          queuedInputChunks: session.chunks.length,
        }
      : bridgeId
        ? { bridgeId, closed: true }
        : undefined,
  };
}

function normalizeMeetKey(value?: string): string | undefined {
  if (!value) {
    return undefined;
  }
  try {
    const url = new URL(value);
    if (url.hostname.toLowerCase() !== "meet.google.com") {
      return value;
    }
    const match = /^\/([a-z]{3}-[a-z]{4}-[a-z]{3})(?:$|[/?#])/i.exec(url.pathname);
    return match?.[1]?.toLowerCase() ?? value;
  } catch {
    return value;
  }
}

function summarizeSession(session: NodeBridgeSession) {
  return {
    bridgeId: session.id,
    url: session.url,
    mode: session.mode,
    closed: session.closed,
    createdAt: session.createdAt,
    closedAt: session.closedAt,
    lastInputAt: session.lastInputAt,
    lastOutputAt: session.lastOutputAt,
    lastInputBytes: session.lastInputBytes,
    lastOutputBytes: session.lastOutputBytes,
  };
}

function listSessions(params: Record<string, unknown>) {
  const urlKey = normalizeMeetKey(readString(params.url));
  const mode = readString(params.mode);
  const bridges = [...sessions.values()]
    .filter((session) => !session.closed)
    .filter((session) => !urlKey || normalizeMeetKey(session.url) === urlKey)
    .filter((session) => !mode || session.mode === mode)
    .map(summarizeSession);
  return { bridges };
}

function stopSessionsByUrl(params: Record<string, unknown>) {
  const urlKey = normalizeMeetKey(readString(params.url));
  if (!urlKey) {
    throw new Error("url required");
  }
  const mode = readString(params.mode);
  const exceptBridgeId = readString(params.exceptBridgeId);
  let stopped = 0;
  for (const [bridgeId, session] of sessions) {
    if (exceptBridgeId && bridgeId === exceptBridgeId) {
      continue;
    }
    if (normalizeMeetKey(session.url) !== urlKey) {
      continue;
    }
    if (mode && session.mode !== mode) {
      continue;
    }
    const wasClosed = session.closed;
    stopSession(session);
    sessions.delete(bridgeId);
    if (!wasClosed) {
      stopped += 1;
    }
  }
  return { ok: true, stopped };
}

function stopChrome(params: Record<string, unknown>) {
  const bridgeId = readString(params.bridgeId);
  if (!bridgeId) {
    return { ok: true, stopped: false };
  }
  const session = sessions.get(bridgeId);
  if (!session) {
    return { ok: true, stopped: false };
  }
  stopSession(session);
  sessions.delete(bridgeId);
  return { ok: true, stopped: true };
}

export async function handleGoogleMeetNodeHostCommand(paramsJSON?: string | null): Promise<string> {
  let raw: unknown = {};
  if (paramsJSON) {
    try {
      raw = JSON.parse(paramsJSON) as unknown;
    } catch {
      throw new Error("Google Meet node host received malformed params JSON.");
    }
  }
  const params = asRecord(raw);
  const action = readString(params.action);
  let result: unknown;
  switch (action) {
    case "setup":
      assertBlackHoleAvailable(10_000);
      result = { ok: true };
      break;
    case "start":
      result = startChrome(params);
      break;
    case "status":
      result = bridgeStatus(params);
      break;
    case "list":
      result = listSessions(params);
      break;
    case "stopByUrl":
      result = stopSessionsByUrl(params);
      break;
    case "pullAudio":
      result = await pullAudio(params);
      break;
    case "pushAudio":
      result = pushAudio(params);
      break;
    case "clearAudio":
      result = clearAudio(params);
      break;
    case "stop":
      result = stopChrome(params);
      break;
    default:
      throw new Error("unsupported googlemeet.chrome action");
  }
  return JSON.stringify(result);
}
