/**
 * ACP Client - Agent Client Protocol connection manager for Electron
 *
 * Spawns an ACP-compatible agent binary as a subprocess and communicates
 * via NDJSON over stdio. Uses @agentclientprotocol/sdk's ClientSideConnection + ndJsonStream.
 *
 * Supported engines:
 * - claude-code:  spawn `claude-code-acp-ts` (npm-local dependency)
 * - qimingcode:    spawn `qimingcode acp` (npm-local dependency)
 *
 * References Tauri client's rcoder_impl.rs pattern:
 * - Binaries installed as npm-local dependencies in ~/.qimingclaw/node_modules/.bin/
 * - CLAUDE_CODE_ACP_PATH env var points to claude-code-acp-ts binary
 * - ACP protocol uses NDJSON (newline-delimited JSON) over stdin/stdout
 */

import { spawn, ChildProcess } from "child_process";
import { Readable, Writable, Transform } from "stream";
import * as path from "path";
import * as os from "os";
import * as fs from "fs";
import { app } from "electron";
import log from "electron-log";
import {
  getAppEnv,
  getQimingCodeBundledBinPath,
  getNodeBinPathWithFallback,
  getClaudeCodeAcpBundledDir,
} from "../../system/dependencies";
import { APP_DATA_DIR_NAME, LOGS_DIR_NAME } from "../../constants";
import { APP_NAME_IDENTIFIER } from "../../../../shared/constants";
import { isWindows } from "../../system/shellEnv";
import { createPlatformAdapter } from "../../system/platformAdapter";
import { spawnJsFile, resolveNpmPackageEntry } from "../../utils/spawnNoWindow";
import { processRegistry } from "../../system/processRegistry";
import { killProcessTreeGraceful } from "../../utils/processTree";
import { perfEmitter } from "../perf/perfEmitter";
import { firstTokenTrace } from "../perf/firstTokenTrace";
import { buildSandboxedSpawnArgs } from "../../sandbox/sandboxProcessWrapper";
import type { SandboxProcessConfig } from "@shared/types/sandbox";

function extractSessionIdFromLine(line: string): string | undefined {
  try {
    const obj = JSON.parse(line) as {
      sessionId?: unknown;
      params?: { sessionId?: unknown };
      result?: { sessionId?: unknown };
      data?: { sessionId?: unknown };
      update?: { sessionId?: unknown };
    };
    const candidates = [
      obj.sessionId,
      obj.params?.sessionId,
      obj.result?.sessionId,
      obj.data?.sessionId,
      obj.update?.sessionId,
    ];
    for (const c of candidates) {
      if (typeof c === "string" && c) return c;
    }
    return undefined;
  } catch {
    return undefined;
  }
}

type McpTransportStatus = "stable" | "reconnecting";

interface McpTransportTelemetry {
  status: McpTransportStatus;
  lastDisconnectAt?: number;
  lastReconnectAttemptAt?: number;
  lastReconnectAt?: number;
  lastSignal?: string;
}

const mcpTransportTelemetry = new WeakMap<
  ChildProcess,
  McpTransportTelemetry
>();

export interface McpTransportSnapshot {
  status: McpTransportStatus;
  lastDisconnectAt?: number;
  lastReconnectAttemptAt?: number;
  lastReconnectAt?: number;
  lastSignal?: string;
}

function ensureTelemetry(proc: ChildProcess): McpTransportTelemetry {
  const existing = mcpTransportTelemetry.get(proc);
  if (existing) return existing;
  const initial: McpTransportTelemetry = { status: "stable" };
  mcpTransportTelemetry.set(proc, initial);
  return initial;
}

function updateMcpTransportTelemetry(proc: ChildProcess, line: string): void {
  const telemetry = ensureTelemetry(proc);
  const lower = line.toLowerCase();
  const now = Date.now();
  const preview = line.length > 240 ? line.slice(0, 240) + "..." : line;

  const isDisconnect =
    (lower.includes("transport error") &&
      (lower.includes("sse stream disconnected") ||
        lower.includes("typeerror: terminated"))) ||
    lower.includes("sse stream disconnected");
  if (isDisconnect) {
    telemetry.status = "reconnecting";
    telemetry.lastDisconnectAt = now;
    telemetry.lastSignal = preview;
    return;
  }

  if (lower.includes("reconnecting in")) {
    telemetry.status = "reconnecting";
    telemetry.lastReconnectAttemptAt = now;
    telemetry.lastSignal = preview;
    return;
  }

  const isReconnected =
    lower.includes("mcp session reconnected") ||
    lower.includes("connected via streamablehttpclienttransport");
  if (isReconnected) {
    telemetry.status = "stable";
    telemetry.lastReconnectAt = now;
    telemetry.lastSignal = preview;
  }
}

export function getMcpTransportSnapshot(
  proc?: ChildProcess | null,
): McpTransportSnapshot | null {
  if (!proc) return null;
  const telemetry = mcpTransportTelemetry.get(proc);
  if (!telemetry) return null;
  return {
    status: telemetry.status,
    lastDisconnectAt: telemetry.lastDisconnectAt,
    lastReconnectAttemptAt: telemetry.lastReconnectAttemptAt,
    lastReconnectAt: telemetry.lastReconnectAt,
    lastSignal: telemetry.lastSignal,
  };
}

export function isMcpReconnectWindowActive(
  proc?: ChildProcess | null,
  windowMs = 4000,
): boolean {
  if (!proc) return false;
  const telemetry = mcpTransportTelemetry.get(proc);
  if (!telemetry) return false;
  const now = Date.now();
  const hasRecentDisconnect =
    telemetry.lastDisconnectAt !== undefined &&
    now - telemetry.lastDisconnectAt <= windowMs;
  const hasRecentReconnect =
    telemetry.lastReconnectAt !== undefined &&
    now - telemetry.lastReconnectAt <= Math.min(windowMs, 1500);
  return (
    telemetry.status === "reconnecting" ||
    hasRecentDisconnect ||
    hasRecentReconnect
  );
}

// ==================== Types ====================

/** ACP MCP Server types (matching @agentclientprotocol/sdk schema) */
export interface AcpEnvVariable {
  name: string;
  value: string;
}

export interface AcpHttpHeader {
  name: string;
  value: string;
}

export type AcpMcpServer =
  | { name: string; command: string; args: string[]; env: AcpEnvVariable[] }
  | { name: string; url: string; headers: AcpHttpHeader[]; type: "http" }
  | { name: string; url: string; headers: AcpHttpHeader[]; type: "sse" };

/** ACP SDK module shape (loaded dynamically since it's ESM) */
export interface AcpSdkModule {
  ndJsonStream: (
    input: WritableStream,
    output: ReadableStream<Uint8Array>,
  ) => unknown;
  ClientSideConnection: new (
    clientFactory: (agent: unknown) => unknown,
    stream: unknown,
  ) => AcpClientSideConnection;
  PROTOCOL_VERSION: number;
}

/** ClientSideConnection interface */
export interface AcpClientSideConnection {
  initialize(params: {
    protocolVersion: number;
    clientCapabilities?: Record<string, unknown>;
  }): Promise<{
    protocolVersion: number;
    agentCapabilities?: Record<string, unknown>;
  }>;

  newSession(params: {
    cwd: string;
    mcpServers: Array<AcpMcpServer>;
    _meta?: { [key: string]: unknown } | null;
  }): Promise<{ sessionId: string }>;

  prompt(params: {
    sessionId: string;
    prompt: Array<{
      type: string;
      text?: string;
      uri?: string;
      mimeType?: string;
    }>;
    _meta?: { [key: string]: unknown } | null;
  }): Promise<{ stopReason: string }>;

  cancel(params: { sessionId: string }): Promise<void>;

  closed: Promise<void>;
}

/** ACP Client handler interface (callbacks from agent → client) */
export interface AcpClientHandler {
  sessionUpdate?(params: {
    sessionId: string;
    update: AcpSessionUpdate;
  }): Promise<void>;

  requestPermission?(
    params: AcpPermissionRequest,
  ): Promise<AcpPermissionResponse>;

  readTextFile?(params: {
    sessionId: string;
    uri: string;
  }): Promise<{ content: string }>;

  writeTextFile?(params: {
    sessionId: string;
    uri: string;
    content: string;
  }): Promise<Record<string, never>>;

  // --- ACP Terminal API (terminal/* methods) ---

  createTerminal?(params: {
    sessionId: string;
    command: string;
    args?: string[];
    env?: Array<{ name: string; value: string }>;
    cwd?: string | null;
    outputByteLimit?: number | null;
  }): Promise<{ terminalId: string }>;

  terminalOutput?(params: { sessionId: string; terminalId: string }): Promise<{
    output: string;
    truncated: boolean;
    exitStatus?: {
      exitCode: number | null;
      signal: string | null;
    } | null;
  }>;

  waitForTerminalExit?(params: {
    sessionId: string;
    terminalId: string;
  }): Promise<{ exitCode: number | null; signal: string | null }>;

  killTerminal?(params: {
    sessionId: string;
    terminalId: string;
  }): Promise<Record<string, never>>;

  releaseTerminal?(params: {
    sessionId: string;
    terminalId: string;
  }): Promise<Record<string, never>>;
}

/** ACP session update types */
export type AcpSessionUpdate =
  | AcpAgentMessageChunk
  | AcpAgentThoughtChunk
  | AcpToolCall
  | AcpToolCallUpdate
  | AcpSessionInfoUpdate
  | AcpUsageUpdate
  | { sessionUpdate: string; [key: string]: unknown };

export interface AcpAgentMessageChunk {
  sessionUpdate: "agent_message_chunk";
  content: { type: string; text?: string };
}

export interface AcpAgentThoughtChunk {
  sessionUpdate: "agent_thought_chunk";
  content: { type: string; text?: string };
}

export interface AcpToolCall {
  sessionUpdate: "tool_call";
  toolCallId: string;
  title: string;
  kind?: string;
  status: string;
  rawInput?: unknown;
  content?: Array<{ type: string; [key: string]: unknown }>;
  locations?: unknown[];
}

export interface AcpToolCallUpdate {
  sessionUpdate: "tool_call_update";
  toolCallId: string;
  status: string;
  /** qimingcode sends kind/title in update even though spec only requires them in tool_call */
  kind?: string;
  title?: string;
  rawInput?: unknown;
  rawOutput?: unknown;
  locations?: Array<{ path?: string; [key: string]: unknown }>;
  content?: Array<{ type: string; [key: string]: unknown }>;
}

export interface AcpSessionInfoUpdate {
  sessionUpdate: "session_info_update";
  title?: string;
  [key: string]: unknown;
}

export interface AcpUsageUpdate {
  sessionUpdate: "usage_update";
  [key: string]: unknown;
}

export type AcpPermissionOptionKind =
  | "allow_once"
  | "allow_always"
  | "reject_once"
  | "reject_always";

export interface AcpPermissionOption {
  optionId: string;
  kind: AcpPermissionOptionKind;
  name: string;
}

export interface AcpPermissionRequest {
  sessionId: string;
  toolCall: {
    toolCallId: string;
    title?: string | null;
    kind?: string | null;
    rawInput?: unknown;
  };
  options: AcpPermissionOption[];
}

export interface AcpPermissionResponse {
  outcome: {
    outcome: "selected" | "cancelled";
    optionId?: string;
  };
}

/** Config for creating an ACP connection */
export interface AcpConnectionConfig {
  /** Binary path to spawn (e.g. claude-code-acp-ts or qimingcode) */
  binPath: string;
  /** Binary arguments (e.g. [] for claude-code-acp-ts, ['acp'] for qimingcode) */
  binArgs: string[];
  /** Whether the binary is a native executable (not a JS file) */
  isNative?: boolean;
  workspaceDir: string;
  apiKey?: string;
  baseUrl?: string;
  model?: string;
  apiProtocol?: string;
  env?: Record<string, string>;
  /** Engine type for process registry tracking */
  engineType?: "claude-code" | "qimingcode";
  /** Purpose of this process (for process registry) */
  purpose?: "engine";
  /** Sandbox wrapping configuration (omit to disable) */
  sandbox?: SandboxProcessConfig;
}

/** Result of creating an ACP connection */
export interface AcpConnectionResult {
  connection: AcpClientSideConnection;
  process: ChildProcess;
  /** Isolated HOME directory created for this ACP process (for cleanup) */
  isolatedHome: string;
  /**
   * 🔧 FIX: Cleanup function to properly dispose of the ACP process.
   * Removes all event listeners to prevent handle leaks.
   *
   * IMPORTANT: Call this before destroying the process to release Windows handles!
   */
  cleanup: () => void;
  /** Cleanup sandbox resources (temp profiles, etc.) */
  sandboxCleanup?: () => void;
}

// ==================== SDK Loader ====================

let _acpSdkPromise: Promise<AcpSdkModule> | null = null;

/**
 * Dynamically load the ACP SDK (@agentclientprotocol/sdk).
 *
 * Uses `new Function('s', 'return import(s)')` to bypass CJS → ESM restriction
 * (tsc compiles import() to require() in CJS mode).
 */
export function loadAcpSdk(): Promise<AcpSdkModule> {
  if (!_acpSdkPromise) {
    const dynamicImport = new Function(
      "specifier",
      "return import(specifier)",
    ) as (specifier: string) => Promise<AcpSdkModule>;

    _acpSdkPromise = dynamicImport("@agentclientprotocol/sdk").catch(
      (error) => {
        log.error("[AcpClient] Failed to load ACP SDK:", error);
        _acpSdkPromise = null;
        throw error;
      },
    );
  }

  return _acpSdkPromise;
}

// ==================== Binary Path ====================

/**
 * Get ACP package directory
 * 优先使用应用内集成的 bundled 路径，回退到 node_modules
 */
function getAcpPackageDir(packageName: string): string | null {
  // claude-code-acp-ts: 优先检查 bundled 目录
  if (packageName === "claude-code-acp-ts") {
    const bundledDir = getClaudeCodeAcpBundledDir();
    if (bundledDir) {
      return bundledDir;
    }
  }

  // 回退到 node_modules
  const nodeModules = path.join(
    app.getPath("home"),
    APP_DATA_DIR_NAME,
    "node_modules",
  );
  const packageDir = path.join(nodeModules, packageName);
  return fs.existsSync(packageDir) ? packageDir : null;
}

function getQimingCodePersistentLogDir(): string {
  return path.join(
    app.getPath("home"),
    APP_DATA_DIR_NAME,
    LOGS_DIR_NAME,
    "qimingcode",
  );
}

/**
 * Resolve ACP binary path for a given engine type.
 *
 * - claude-code → ~/.qimingclaw/node_modules/claude-code-acp-ts (JS entry, spawned via node)
 * - qimingcode   → native Go binary (spawned directly, not via node)
 *
 * For qimingcode, we resolve the platform-specific native binary directly
 * instead of going through the JS wrapper (qimingcode/bin/qimingcode).
 *
 * Reasons:
 * 1. The JS wrapper uses `spawnSync(binary, args, { stdio: 'inherit' })`
 *    without `windowsHide: true`, causing console popup on Windows.
 * 2. The intermediate Node.js process adds an unnecessary process layer
 *    that can interfere with SIGTERM propagation and stdio piping.
 * 3. Spawning the native binary directly is faster and more reliable.
 *
 * Returns `isNative: true` when the binary should be spawned directly
 * (not via `node`).
 */
export function resolveAcpBinary(engine: "claude-code" | "qimingcode"): {
  binPath: string;
  binArgs: string[];
  isNative: boolean;
} {
  if (engine === "claude-code") {
    const packageDir = getAcpPackageDir("claude-code-acp-ts");
    const entryPath = packageDir
      ? resolveNpmPackageEntry(packageDir, "claude-code-acp-ts")
      : null;
    return {
      binPath: entryPath || "",
      binArgs: [],
      isNative: false,
    };
  }

  // qimingcode: resolve platform-specific native binary directly
  const nativePath = resolveQimingCodeNativeBinary();
  if (nativePath) {
    log.info(`[AcpClient] qimingcode: using native binary: ${nativePath}`);
    return {
      binPath: nativePath,
      binArgs: ["acp"],
      isNative: true,
    };
  }

  // Fallback: use JS wrapper (will have Windows popup issue)
  log.warn(
    "[AcpClient] qimingcode: native binary not found, falling back to JS wrapper",
  );
  const packageDir = getAcpPackageDir("qimingcode");
  const entryPath = packageDir
    ? resolveNpmPackageEntry(packageDir, "qimingcode")
    : null;
  return {
    binPath: entryPath || "",
    binArgs: ["acp"],
    isNative: false,
  };
}

/**
 * Resolve the platform-specific qimingcode native binary path.
 *
 * qimingcode npm package uses optionalDependencies with platform-specific packages:
 * - qimingcode-darwin-arm64/bin/qimingcode
 * - qimingcode-windows-x64/bin/qimingcode.exe
 * - qimingcode-linux-x64/bin/qimingcode
 * etc.
 *
 * Logic mirrors qimingcode/bin/qimingcode JS wrapper.
 */
function resolveQimingCodeNativeBinary(): string | null {
  // 应用内打包的二进制（唯一来源）
  const bundledPath = getQimingCodeBundledBinPath();
  if (bundledPath) {
    log.info("[AcpClient] qimingcode: using bundled binary:", bundledPath);
    return bundledPath;
  }

  log.error("[AcpClient] qimingcode: bundled binary not found");
  return null;
}

// ==================== Connection Factory ====================

/**
 * Create an ACP connection by spawning an agent binary and establishing
 * a ClientSideConnection over NDJSON stdin/stdout.
 *
 * Works with any ACP-compatible binary:
 * - claude-code-acp-ts (no args)
 * - qimingcode acp (args: ['acp'])
 */
export async function createAcpConnection(
  config: AcpConnectionConfig,
  clientHandler: AcpClientHandler,
): Promise<AcpConnectionResult> {
  const { binPath, binArgs } = config;
  let effectiveBinArgs = [...binArgs];

  if (!fs.existsSync(binPath)) {
    throw new Error(
      `ACP binary not found at: ${binPath}. Please install it first.`,
    );
  }

  if (config.engineType === "qimingcode" && firstTokenTrace.isDeepMode()) {
    if (!effectiveBinArgs.includes("--print-logs")) {
      effectiveBinArgs.push("--print-logs");
    }
    if (!effectiveBinArgs.includes("--log-level")) {
      effectiveBinArgs.push(
        "--log-level",
        process.env.QIMING_TRACE_QIMINGCODE_LOG_LEVEL || "DEBUG",
      );
    }
    if (!effectiveBinArgs.includes("--log-dir")) {
      const traceLogDir = firstTokenTrace.getQimingCodeLogDir();
      if (traceLogDir) {
        fs.mkdirSync(traceLogDir, { recursive: true });
        effectiveBinArgs.push("--log-dir", traceLogDir);
      }
    }
    firstTokenTrace.trace(
      "acp.conn.qimingcode.trace_flags",
      { engine: config.engineType },
      { binPath, args: effectiveBinArgs },
    );
  }

  const setupTimer = perfEmitter.start();

  // Build isolated environment (aligned with rcoder + engineManager pattern)
  // 1. Start with getAppEnv() for complete isolation (node/npm/uv paths, no system PATH)
  // 2. Create isolated HOME/config dir so Claude Code uses empty config (not user's global ~/.claude/)
  // 3. Only inject model vars from ACP-provided config

  // Create isolated HOME directory with empty .claude/ config
  // This prevents Claude Code from reading user's global ~/.claude/settings.json
  const runId = `acp-${Date.now()}-${Math.random().toString(36).substring(2, 8)}`;
  const isolatedHome = path.join(
    os.tmpdir(),
    `${APP_NAME_IDENTIFIER}-${runId}`,
  );
  fs.mkdirSync(path.join(isolatedHome, ".claude"), { recursive: true });

  // 获取应用隔离环境变量（包含隔离的 PATH、npm、uv 配置等）
  const appEnv = getAppEnv();

  // 构建最终环境变量：以 appEnv 为基础，添加 ACP 特定配置
  const env: Record<string, string> = {
    ...appEnv, // 包含完全隔离的 PATH、NODE_PATH、npm/uv 配置等

    // Isolated HOME — Claude Code won't read user's global config
    HOME: isolatedHome,
    USERPROFILE: isolatedHome, // Windows

    // XDG 目录（Unix/Linux 标准，Windows 上也设置以兼容可能的工具）
    XDG_CONFIG_HOME: path.join(isolatedHome, ".config"),
    XDG_DATA_HOME: path.join(isolatedHome, ".local", "share"),
    XDG_CACHE_HOME: path.join(isolatedHome, ".cache"),

    // 引擎配置目录
    CLAUDE_CONFIG_DIR: path.join(isolatedHome, ".claude"),
    QIMINGCODE_CONFIG_DIR: path.join(isolatedHome, ".qimingcode"),

    // Disable non-essential traffic (aligned with rcoder ENV_DISABLE_NONESSENTIAL)
    CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC: "1",
  };

  // Set TMPDIR to isolatedHome/tmp so that sandboxed engines (e.g. claude-code
  // under macOS seatbelt strict mode) create temp files inside a writable path.
  // Without this, os.tmpdir() resolves to /private/tmp which is NOT in the
  // seatbelt writablePaths, causing EPERM on mkdir for Bash/Glob tools.
  const isolatedTmp = path.join(isolatedHome, "tmp");
  fs.mkdirSync(isolatedTmp, { recursive: true });
  env.TMPDIR = isolatedTmp;
  env.TEMP = isolatedTmp;
  env.TMP = isolatedTmp;

  const isQimingCodeEngine = config.engineType === "qimingcode";

  // Set model/api vars from ACP config only (never from user's global env)
  if (config.apiKey) {
    env.ANTHROPIC_API_KEY = config.apiKey;
    env.ANTHROPIC_AUTH_TOKEN = config.apiKey;
  }
  if (config.baseUrl) env.ANTHROPIC_BASE_URL = config.baseUrl;
  // config.model 必须由上层设置（ensureEngineForRequest 从 model_provider 或 agent_config env 提取）
  if (config.model) {
    env.ANTHROPIC_MODEL = config.model;
  } else {
    log.warn(
      "[AcpClient] ⚠️ config.model not set, engine will use built-in default model (not recommended)",
    );
  }
  if (config.env) Object.assign(env, config.env);

  // qimingcode runs on opencode and prefers OPENCODE_MODEL.
  // For openai-compatible models, OPENAI_* creds are required for provider autoload.
  if (isQimingCodeEngine) {
    if (config.model && !env.OPENCODE_MODEL) {
      env.OPENCODE_MODEL = config.model;
    }

    const effectiveModel = env.OPENCODE_MODEL || config.model || "";
    const apiProtocol = (config.apiProtocol || "").toLowerCase();
    const isOpenAICompatible =
      apiProtocol === "openai" ||
      effectiveModel.startsWith("openai-compatible/");

    if (isOpenAICompatible) {
      if (config.apiKey && !env.OPENAI_API_KEY) {
        env.OPENAI_API_KEY = config.apiKey;
      }
      if (config.baseUrl && !env.OPENAI_BASE_URL) {
        env.OPENAI_BASE_URL = config.baseUrl;
      }

      // Compatibility aliases used by some opencode paths.
      if (env.OPENAI_API_KEY && !env.OPENCODE_OPENAI_API_KEY) {
        env.OPENCODE_OPENAI_API_KEY = env.OPENAI_API_KEY;
      }
      if (env.OPENAI_BASE_URL && !env.OPENCODE_OPENAI_API_BASE) {
        env.OPENCODE_OPENAI_API_BASE = env.OPENAI_BASE_URL;
      }
    }
  }

  // Ensure qimingcode writes detailed logs to persistent app logs directory.
  // Without this, logs default to isolated XDG paths under /tmp and are removed on destroy.
  if (config.engineType === "qimingcode" && !env.OPENCODE_LOG_DIR) {
    const persistentLogDir = getQimingCodePersistentLogDir();
    fs.mkdirSync(persistentLogDir, { recursive: true });
    env.OPENCODE_LOG_DIR = persistentLogDir;
  }

  // Set CLAUDE_CODE_ACP_PATH for claude-code-acp-ts (matching Tauri's rcoder pattern)
  if (binPath.includes("claude-code-acp-ts")) {
    env.CLAUDE_CODE_ACP_PATH = binPath;
  }

  const envMs = setupTimer.end("acp.conn.env", {
    engine: config.engineType ?? "unknown",
  });

  // 打印最终生效的模型配置（关键调试信息）
  log.info("[AcpClient] 🚀 Spawning ACP binary", {
    binPath,
    binArgs: effectiveBinArgs,
    cwd: config.workspaceDir,
    isolatedHome,
    ANTHROPIC_MODEL: env.ANTHROPIC_MODEL || "(not set)",
    ANTHROPIC_BASE_URL: env.ANTHROPIC_BASE_URL || "(not set)",
    ANTHROPIC_API_KEY: env.ANTHROPIC_API_KEY
      ? env.ANTHROPIC_API_KEY.slice(
          0,
          Math.min(8, Math.floor(env.ANTHROPIC_API_KEY.length / 2)),
        ) + "..."
      : "(not set)",
    OPENCODE_MODEL: env.OPENCODE_MODEL || "(not set)",
    OPENCODE_LOG_DIR: env.OPENCODE_LOG_DIR || "(not set)",
    OPENAI_BASE_URL: env.OPENAI_BASE_URL || "(not set)",
    OPENAI_API_KEY: env.OPENAI_API_KEY
      ? env.OPENAI_API_KEY.slice(
          0,
          Math.min(8, Math.floor(env.OPENAI_API_KEY.length / 2)),
        ) + "..."
      : "(not set)",
    OPENCODE_OPENAI_API_BASE: env.OPENCODE_OPENAI_API_BASE || "(not set)",
    OPENCODE_OPENAI_API_KEY: env.OPENCODE_OPENAI_API_KEY
      ? env.OPENCODE_OPENAI_API_KEY.slice(
          0,
          Math.min(8, Math.floor(env.OPENCODE_OPENAI_API_KEY.length / 2)),
        ) + "..."
      : "(not set)",
  });

  // 1. Spawn ACP binary
  // On Unix, use detached: true so the child gets its own process group,
  // enabling process.kill(-pid) to kill the entire tree on cleanup.
  const spawnTimer = perfEmitter.start();
  const useDetached = !isWindows;
  let proc: ChildProcess;
  let sandboxCleanup: (() => void) | undefined;

  // --- Sandbox wrapping ---
  // 沙箱启用时，将引擎二进制包装在 sandbox-exec / bwrap / qiming sandbox helper 中
  let spawnCommand = binPath;
  let spawnArgs = effectiveBinArgs;
  let sandboxed = false;

  if (config.sandbox?.enabled) {
    try {
      // 对于 JS 引擎（非 native），使用 node 二进制作为底层 command。
      // 避免沙箱内运行 Electron 主程序导致 IOKit/PNG 操作崩溃（SIGSEGV）。
      // 对于原生引擎（qimingcode Go 二进制），直接使用 binPath。
      const effectiveCommand = config.isNative
        ? binPath
        : (getNodeBinPathWithFallback() ?? "node");
      const effectiveSpawnArgs = config.isNative
        ? effectiveBinArgs
        : [binPath, ...effectiveBinArgs];

      // Extra writable paths for seatbelt profile:
      // 1. isolatedHome — engine config/cache
      // 2. App data directory (~/.qimingclaw) — engine logs, npm packages, config
      // 3. System temp directories — engines may create temp files here for tool
      //    execution. Cross-platform: os.tmpdir() + realpath, plus macOS-specific
      //    /tmp and /private/tmp (some engines hardcode these instead of os.tmpdir()).
      const extraWritable: string[] = [isolatedHome, os.tmpdir()];

      // App data directory (e.g. ~/.qimingclaw) — engine writes logs, npm packages, etc.
      const appDataDir = path.join(app.getPath("home"), APP_DATA_DIR_NAME);
      extraWritable.push(appDataDir);

      try {
        extraWritable.push(fs.realpathSync(os.tmpdir()));
      } catch {
        /* realpath resolution failed, skip */
      }
      if (createPlatformAdapter().isMacOS) {
        extraWritable.push("/tmp", "/private/tmp");
      }

      const wrapped = await buildSandboxedSpawnArgs(
        effectiveCommand,
        effectiveSpawnArgs,
        config.workspaceDir,
        config.sandbox,
        extraWritable,
      );
      spawnCommand = wrapped.command;
      spawnArgs = wrapped.args;
      sandboxCleanup = wrapped.cleanupSandbox;
      sandboxed = spawnCommand !== effectiveCommand;

      log.info("[AcpClient] Sandbox wrapping applied:", {
        type: config.sandbox.type,
        originalCommand: binPath,
        wrappedCommand: spawnCommand,
        sandboxed,
      });
    } catch (sandboxError) {
      log.error("[AcpClient] Sandbox wrapping failed:", sandboxError);
      // fallback 当前由 acpEngine.ts 固定为 "degrade_to_off"，
      // "fail_closed" 分支目前不可达，保留以备将来恢复配置项。
      if (config.sandbox.fallback === "fail_closed") {
        throw new Error(
          `Sandbox setup failed: ${sandboxError instanceof Error ? sandboxError.message : String(sandboxError)}`,
        );
      }
      // degrade_to_off: 继续无沙箱启动
      log.warn("[AcpClient] Degrading to non-sandboxed execution");
    }
  }

  if (sandboxed) {
    // 沙箱已包装：直接 spawn（沙箱 wrapper 本身就是 command）
    proc = spawn(spawnCommand, spawnArgs, {
      cwd: config.workspaceDir,
      env,
      stdio: ["pipe", "pipe", "pipe"],
      windowsHide: true,
      detached: useDetached,
    });
    log.info(
      `[AcpClient] Spawned sandboxed process: ${spawnCommand} (detached=${useDetached})`,
    );
  } else if (config.isNative) {
    // Native binary (e.g. qimingcode Go binary): spawn directly, no node wrapper
    // This avoids Windows console popup and eliminates the intermediate process
    proc = spawn(binPath, effectiveBinArgs, {
      cwd: config.workspaceDir,
      env,
      stdio: ["pipe", "pipe", "pipe"],
      windowsHide: true,
      detached: useDetached,
    });
    log.info(
      `[AcpClient] Spawned native binary directly: ${binPath} (detached=${useDetached})`,
    );
  } else {
    // JS file (e.g. claude-code-acp-ts): spawn via node using spawnJsFile
    proc = spawnJsFile(binPath, effectiveBinArgs, {
      cwd: config.workspaceDir,
      env,
      stdio: ["pipe", "pipe", "pipe"],
      detached: useDetached,
    });
  }
  // Unref so the parent process can exit without waiting for the child
  // (we manage cleanup explicitly via killProcessTree)
  if (useDetached) {
    proc.unref();
  }

  const spawnMs = spawnTimer.end("acp.conn.spawn", {
    engine: config.engineType ?? "unknown",
    native: !!config.isNative,
  });

  // Register process in the process registry for orphan detection
  if (proc.pid) {
    processRegistry.register(proc.pid, {
      engineId: runId,
      engineType: config.engineType ?? "claude-code",
      purpose: config.purpose ?? "engine",
    });
  }
  ensureTelemetry(proc);

  // Log stderr — 详细输出所有内容
  proc.stderr?.on("data", (data: Buffer) => {
    const text = data.toString().trim();
    if (!text) return;
    const lower = text.toLowerCase();
    if (
      lower.includes("error") ||
      lower.includes("failed") ||
      lower.includes("enoent") ||
      lower.includes("spawn") ||
      lower.includes("mcp server") ||
      lower.includes("certificate") ||
      lower.includes("models.dev") ||
      lower.includes("providers") ||
      lower.includes("rate limit") ||
      lower.includes("使用上限")
    ) {
      log.error("[AcpClient stderr] 🔴", text);
    } else {
      log.warn("[AcpClient stderr]", text);
    }
    for (const line of text.split("\n")) {
      const trimmed = line.trim();
      if (!trimmed) continue;
      updateMcpTransportTelemetry(proc, trimmed);
    }
    if (firstTokenTrace.isDeepMode()) {
      for (const line of text.split("\n")) {
        const trimmed = line.trim();
        if (!trimmed) continue;
        const preview =
          trimmed.length > 1000 ? trimmed.substring(0, 1000) + "..." : trimmed;
        firstTokenTrace.trace(
          "acp.stderr.line",
          {
            engine: config.engineType,
            sessionId: extractSessionIdFromLine(trimmed),
          },
          { pid: proc.pid, line: preview },
        );
      }
    }
  });

  proc.on("error", (error) => {
    log.error("[AcpClient] Process error:", error);
  });

  proc.on("exit", (code, signal) => {
    log.info("[AcpClient] Process exited", { code, signal });
  });

  /**
   * 使用 Transform 流对 stdout 做“仅打日志并透传”，避免与 SDK 争抢同一 Readable。
   * 若直接对 proc.stdout 同时 on('data') 和 Readable.toWeb(proc.stdout)，
   * Node 会形成两个消费者竞争，session/update 通知可能被 data 监听器消费，
   * SDK 收不到，导致没有 agent_message_chunk / agent_thought_chunk，前端无消息返回。
   * 0.8.1 能正常返回正是因为只有 SDK 一个消费者；新版曾加的 stdout 调试监听器导致回退。
   */
  const stdoutLogTransform = new Transform({
    transform(chunk: Buffer, _encoding, callback) {
      const text = chunk.toString();
      for (const line of text.split("\n")) {
        const trimmed = line.trim();
        if (!trimmed) continue;
        const preview =
          trimmed.length > 500 ? trimmed.substring(0, 500) + "..." : trimmed;
        log.info("[AcpClient stdout] 📥", preview);
        if (firstTokenTrace.isDeepMode()) {
          firstTokenTrace.trace(
            "acp.stdout.line",
            {
              engine: config.engineType,
              sessionId: extractSessionIdFromLine(trimmed),
            },
            { pid: proc.pid, line: preview },
          );
        }
      }
      this.push(chunk);
      callback();
    },
  });
  proc.stdout!.pipe(stdoutLogTransform);

  // Debug: log raw stdin NDJSON lines sent to ACP process (stdin 只写不读，无多消费者问题)
  const originalStdinWrite = proc.stdin!.write.bind(proc.stdin!);
  proc.stdin!.write = function (chunk: any, ...args: any[]) {
    const text =
      typeof chunk === "string" ? chunk : Buffer.from(chunk).toString();
    for (const line of text.split("\n")) {
      const trimmed = line.trim();
      if (!trimmed) continue;
      const preview =
        trimmed.length > 500 ? trimmed.substring(0, 500) + "..." : trimmed;
      log.info("[AcpClient stdin] 📤", preview);
      if (firstTokenTrace.isDeepMode()) {
        firstTokenTrace.trace(
          "acp.stdin.line",
          {
            engine: config.engineType,
            sessionId: extractSessionIdFromLine(trimmed),
          },
          { pid: proc.pid, line: preview },
        );
      }
    }
    return originalStdinWrite(chunk, ...args);
  } as any;

  // 2. Convert Node streams → Web streams（仅从 stdoutLogTransform 读，保证唯一消费者）
  // Wrap post-spawn setup in try/catch: if anything fails after spawn,
  // we must kill the process and unregister it to prevent orphans.
  const bridgeTimer = perfEmitter.start();
  let readable: ReadableStream<Uint8Array>;
  let writable: WritableStream;
  let acp: any;
  let stream: any;
  let connection: AcpClientSideConnection;

  try {
    const ioBridgeTimer = perfEmitter.start();
    readable = Readable.toWeb(stdoutLogTransform) as ReadableStream<Uint8Array>;
    writable = Writable.toWeb(proc.stdin!) as WritableStream;
    ioBridgeTimer.end("acp.conn.ioBridge", {
      engine: config.engineType ?? "unknown",
    });

    // 3. Load ACP SDK and create NDJSON stream
    const sdkTimer = perfEmitter.start();
    acp = await loadAcpSdk();
    sdkTimer.end("acp.conn.sdkLoad", {
      engine: config.engineType ?? "unknown",
    });

    const streamTimer = perfEmitter.start();
    stream = acp.ndJsonStream(writable, readable);
    streamTimer.end("acp.conn.ndjson", {
      engine: config.engineType ?? "unknown",
    });

    // 4. Create ClientSideConnection with client handler
    const connTimer = perfEmitter.start();
    connection = new acp.ClientSideConnection(
      (_agent: unknown) => clientHandler,
      stream,
    ) as AcpClientSideConnection;
    connTimer.end("acp.conn.connection", {
      engine: config.engineType ?? "unknown",
    });
  } catch (e) {
    // Post-spawn setup failed — kill the spawned process to prevent orphan
    log.error("[AcpClient] Post-spawn setup failed, killing process:", e);
    if (proc.pid) {
      processRegistry.unregister(proc.pid);
      await killProcessTreeGraceful(proc.pid, 3000).catch(() => {});
    } else {
      proc.kill();
    }
    throw e;
  }

  const bridgeMs = bridgeTimer.end("acp.conn.bridgeTotal", {
    engine: config.engineType ?? "unknown",
  });

  perfEmitter.duration("acp.conn.create.total", envMs + spawnMs + bridgeMs, {
    engine: config.engineType ?? "unknown",
  });

  // 🔧 FIX: Create cleanup function to properly dispose of event listeners
  // This prevents handle leaks by removing all event listeners before process termination
  const cleanup = () => {
    try {
      // Remove stdout listener (prevents handle leak)
      proc.stdout?.removeAllListeners();
      // Remove stderr listener (prevents handle leak)
      proc.stderr?.removeAllListeners();
      // Remove stdin listener (also restores the wrapped write function)
      proc.stdin?.removeAllListeners();
      // Remove process-level listeners (error, exit)
      proc.removeAllListeners();
      mcpTransportTelemetry.delete(proc);
      log.info(
        "[AcpClient] 🧹 Cleaned up event listeners to prevent handle leaks",
      );
    } catch (e) {
      log.warn("[AcpClient] Cleanup error:", e);
    }
  };

  return {
    connection,
    process: proc,
    isolatedHome,
    cleanup,
    sandboxCleanup,
  };
}