/**
 * Path Utilities
 * Cross-platform path resolution helpers
 */
import { createRequire } from 'node:module';
import { dirname, isAbsolute, join, normalize } from 'path';
import { homedir } from 'os';
import { cpSync, existsSync, mkdirSync, readFileSync, realpathSync, rmSync } from 'fs';

const require = createRequire(import.meta.url);

type ElectronAppLike = Pick<typeof import('electron').app, 'isPackaged' | 'getPath' | 'getAppPath'>;
type OpenClawRuntimeSource = 'dev' | 'external' | 'managed' | 'bundled' | 'missing';

type OpenClawRuntimeResolution = {
  dir: string;
  source: OpenClawRuntimeSource;
  version?: string;
  bundledDir?: string;
  managedDir?: string;
  installedFromBundled?: boolean;
};

let cachedOpenClawRuntime: OpenClawRuntimeResolution | null = null;

// Modules that Zhinian loads from the OpenClaw package context at main-process
// module initialization time.  Some user-installed or previously managed
// OpenClaw packages are valid CLIs but do not include these app-side
// integration dependencies; selecting them would crash before the UI opens.
const REQUIRED_OPENCLAW_CONTEXT_MODULES = [
  '@whiskeysockets/baileys/package.json',
  'qrcode-terminal/package.json',
  'qrcode-terminal/vendor/QRCode/index.js',
  'qrcode-terminal/vendor/QRCode/QRErrorCorrectLevel.js',
] as const;

export {
  quoteForCmd,
  needsWinShell,
  prepareWinSpawn,
  normalizeNodeRequirePathForNodeOptions,
  appendNodeRequireToNodeOptions,
} from './win-shell';

function getElectronApp() {
  if (process.versions?.electron) {
    return (require('electron') as typeof import('electron')).app;
  }

  const fallbackUserData = process.env.CLAWX_USER_DATA_DIR?.trim() || join(homedir(), '.clawx');
  const fallbackAppPath = process.cwd();
  const fallbackApp: ElectronAppLike = {
    isPackaged: false,
    getPath: (name) => {
      if (name === 'userData') return fallbackUserData;
      return fallbackUserData;
    },
    getAppPath: () => fallbackAppPath,
  };
  return fallbackApp;
}

/**
 * Expand ~ to home directory
 */
export function expandPath(path: string): string {
  if (path.startsWith('~')) {
    return path.replace('~', homedir());
  }
  return path;
}

/**
 * Get OpenClaw config directory
 */
export function getOpenClawConfigDir(): string {
  return join(homedir(), '.openclaw');
}

/**
 * Get OpenClaw skills directory
 */
export function getOpenClawSkillsDir(): string {
  return join(getOpenClawConfigDir(), 'skills');
}

/**
 * Get ClawX config directory
 */
export function getClawXConfigDir(): string {
  return join(homedir(), '.clawx');
}

/**
 * Get ClawX logs directory
 */
export function getLogsDir(): string {
  return join(getElectronApp().getPath('userData'), 'logs');
}

/**
 * Get ClawX data directory
 */
export function getDataDir(): string {
  return getElectronApp().getPath('userData');
}

/**
 * Ensure directory exists
 */
export function ensureDir(dir: string): void {
  if (!existsSync(dir)) {
    mkdirSync(dir, { recursive: true });
  }
}

function fsPath(filePath: string): string {
  if (process.platform !== 'win32') return filePath;
  if (!filePath) return filePath;
  if (filePath.startsWith('\\\\?\\')) return filePath;
  const windowsPath = filePath.replace(/\//g, '\\');
  if (!isAbsolute(windowsPath)) return windowsPath;
  if (windowsPath.startsWith('\\\\')) {
    return `\\\\?\\UNC\\${windowsPath.slice(2)}`;
  }
  return `\\\\?\\${windowsPath}`;
}

function normalizeCandidatePath(dir: string): string {
  return normalize(expandPath(dir.trim()));
}

function readOpenClawVersion(dir: string): string | undefined {
  try {
    const pkgPath = join(dir, 'package.json');
    if (existsSync(fsPath(pkgPath))) {
      const pkg = JSON.parse(readFileSync(fsPath(pkgPath), 'utf-8')) as { version?: string };
      return pkg.version;
    }
  } catch {
    // Ignore version read errors.
  }
  return undefined;
}

function isValidOpenClawPackageDir(dir: string): boolean {
  return Boolean(dir)
    && existsSync(fsPath(dir))
    && existsSync(fsPath(join(dir, 'package.json')))
    && existsSync(fsPath(join(dir, 'openclaw.mjs')));
}

function hasRequiredOpenClawContextModules(dir: string): boolean {
  if (!isValidOpenClawPackageDir(dir)) return false;

  try {
    const runtimeRequire = createRequire(join(realpathSync(fsPath(dir)), 'package.json'));
    for (const specifier of REQUIRED_OPENCLAW_CONTEXT_MODULES) {
      runtimeRequire.resolve(specifier);
    }
    return true;
  } catch {
    try {
      const runtimeRequire = createRequire(join(dir, 'package.json'));
      for (const specifier of REQUIRED_OPENCLAW_CONTEXT_MODULES) {
        runtimeRequire.resolve(specifier);
      }
      return true;
    } catch {
      return false;
    }
  }
}

function samePath(left: string, right: string): boolean {
  try {
    return realpathSync(fsPath(left)) === realpathSync(fsPath(right));
  } catch {
    return normalize(left) === normalize(right);
  }
}

function logOpenClawRuntime(message: string, extra?: unknown): void {
  try {
    const { logger } = require('./logger') as typeof import('./logger');
    if (extra === undefined) {
      logger.info(message);
    } else {
      logger.info(message, extra);
    }
  } catch {
    // Logger may be unavailable in unit tests or non-Electron contexts.
  }
}

function getBundledOpenClawDir(): string {
  if (getElectronApp().isPackaged) {
    return join(process.resourcesPath, 'openclaw');
  }
  return join(__dirname, '../../node_modules/openclaw');
}

function getManagedOpenClawDir(): string {
  return join(getOpenClawConfigDir(), 'runtime', 'openclaw');
}

function getEnvOpenClawCandidates(): string[] {
  return [
    process.env.YINIAN_OPENCLAW_DIR,
    process.env.CLAWX_OPENCLAW_DIR,
    process.env.OPENCLAW_DIR,
  ].filter((value): value is string => Boolean(value?.trim()));
}

function getStandardOpenClawCandidates(): string[] {
  const home = homedir();
  const candidates = [
    join(home, '.openclaw', 'openclaw'),
    join(home, '.openclaw', 'node_modules', 'openclaw'),
    join(home, '.npm-global', 'lib', 'node_modules', 'openclaw'),
    join(home, '.local', 'lib', 'node_modules', 'openclaw'),
  ];

  if (process.platform === 'darwin') {
    candidates.push(
      '/usr/local/lib/node_modules/openclaw',
      '/opt/homebrew/lib/node_modules/openclaw',
    );
  } else if (process.platform === 'linux') {
    candidates.push(
      '/usr/local/lib/node_modules/openclaw',
      '/usr/lib/node_modules/openclaw',
    );
  } else if (process.platform === 'win32') {
    const appData = process.env.APPDATA;
    const programFiles = process.env.ProgramFiles;
    const programFilesX86 = process.env['ProgramFiles(x86)'];
    if (appData) candidates.push(join(appData, 'npm', 'node_modules', 'openclaw'));
    if (programFiles) candidates.push(join(programFiles, 'nodejs', 'node_modules', 'openclaw'));
    if (programFilesX86) candidates.push(join(programFilesX86, 'nodejs', 'node_modules', 'openclaw'));
  }

  return candidates;
}

function findExternalOpenClawDir(excludedDirs: string[]): string | null {
  const seen = new Set<string>();
  const candidates = [...getEnvOpenClawCandidates(), ...getStandardOpenClawCandidates()];

  for (const rawCandidate of candidates) {
    const candidate = normalizeCandidatePath(rawCandidate);
    if (seen.has(candidate)) continue;
    seen.add(candidate);
    if (excludedDirs.some((excluded) => samePath(candidate, excluded))) continue;
    if (!isValidOpenClawPackageDir(candidate)) continue;
    if (hasRequiredOpenClawContextModules(candidate)) return candidate;
    logOpenClawRuntime('[openclaw-runtime] Ignoring external OpenClaw installation because required app dependencies are missing', {
      candidate,
      requiredModules: REQUIRED_OPENCLAW_CONTEXT_MODULES,
    });
  }

  return null;
}

function installBundledOpenClawToManagedRuntime(bundledDir: string, managedDir: string): boolean {
  if (!isValidOpenClawPackageDir(bundledDir)) return false;

  const bundledVersion = readOpenClawVersion(bundledDir);
  const managedVersion = isValidOpenClawPackageDir(managedDir)
    ? readOpenClawVersion(managedDir)
    : undefined;

  if (managedVersion && bundledVersion && managedVersion === bundledVersion && hasRequiredOpenClawContextModules(managedDir)) {
    return false;
  }

  const tempDir = `${managedDir}.tmp-${Date.now()}`;
  rmSync(fsPath(tempDir), { recursive: true, force: true });
  mkdirSync(fsPath(dirname(tempDir)), { recursive: true });
  cpSync(fsPath(bundledDir), fsPath(tempDir), { recursive: true, dereference: true });
  rmSync(fsPath(managedDir), { recursive: true, force: true });
  cpSync(fsPath(tempDir), fsPath(managedDir), { recursive: true, dereference: true });
  rmSync(fsPath(tempDir), { recursive: true, force: true });
  return true;
}

function resolveOpenClawRuntime(): OpenClawRuntimeResolution {
  if (cachedOpenClawRuntime) return cachedOpenClawRuntime;

  const app = getElectronApp();
  const bundledDir = getBundledOpenClawDir();
  const managedDir = getManagedOpenClawDir();

  if (!app.isPackaged) {
    cachedOpenClawRuntime = {
      dir: bundledDir,
      source: isValidOpenClawPackageDir(bundledDir) ? 'dev' : 'missing',
      version: readOpenClawVersion(bundledDir),
      bundledDir,
      managedDir,
    };
    return cachedOpenClawRuntime;
  }

  if (hasRequiredOpenClawContextModules(managedDir)) {
    cachedOpenClawRuntime = {
      dir: managedDir,
      source: 'managed',
      version: readOpenClawVersion(managedDir),
      bundledDir,
      managedDir,
    };
    logOpenClawRuntime('[openclaw-runtime] Using managed OpenClaw runtime', cachedOpenClawRuntime);
    return cachedOpenClawRuntime;
  }

  const externalDir = findExternalOpenClawDir([bundledDir, managedDir]);
  if (externalDir) {
    cachedOpenClawRuntime = {
      dir: externalDir,
      source: 'external',
      version: readOpenClawVersion(externalDir),
      bundledDir,
      managedDir,
    };
    logOpenClawRuntime('[openclaw-runtime] Using existing OpenClaw installation before managed runtime is installed', cachedOpenClawRuntime);
    return cachedOpenClawRuntime;
  }

  let installedFromBundled = false;
  if (isValidOpenClawPackageDir(bundledDir)) {
    try {
      installedFromBundled = installBundledOpenClawToManagedRuntime(bundledDir, managedDir);
    } catch (error) {
      logOpenClawRuntime('[openclaw-runtime] Failed to install bundled OpenClaw runtime, falling back to bundled resources', error);
    }
  }

  if (hasRequiredOpenClawContextModules(managedDir)) {
    cachedOpenClawRuntime = {
      dir: managedDir,
      source: 'managed',
      version: readOpenClawVersion(managedDir),
      bundledDir,
      managedDir,
      installedFromBundled,
    };
    logOpenClawRuntime(
      installedFromBundled
        ? '[openclaw-runtime] Installed bundled OpenClaw runtime'
        : '[openclaw-runtime] Using managed OpenClaw runtime',
      cachedOpenClawRuntime,
    );
    return cachedOpenClawRuntime;
  }

  if (isValidOpenClawPackageDir(managedDir)) {
    logOpenClawRuntime('[openclaw-runtime] Ignoring managed OpenClaw runtime because required app dependencies are missing', {
      managedDir,
      requiredModules: REQUIRED_OPENCLAW_CONTEXT_MODULES,
    });
  }

  cachedOpenClawRuntime = {
    dir: bundledDir,
    source: isValidOpenClawPackageDir(bundledDir) ? 'bundled' : 'missing',
    version: readOpenClawVersion(bundledDir),
    bundledDir,
    managedDir,
  };
  return cachedOpenClawRuntime;
}

/**
 * Get resources directory (for bundled assets)
 */
export function getResourcesDir(): string {
  if (getElectronApp().isPackaged) {
    return join(process.resourcesPath, 'resources');
  }
  return join(__dirname, '../../resources');
}

/**
 * Get preload script path
 */
export function getPreloadPath(): string {
  return join(__dirname, '../preload/index.js');
}

/**
 * Get OpenClaw package directory.
 *
 * Runtime resolution policy:
 * 1. Development uses workspace node_modules/openclaw.
 * 2. Packaged builds first adapt an existing user/system OpenClaw package.
 * 3. If none exists, copy the bundled OpenClaw package into
 *    ~/.openclaw/runtime/openclaw and run from there.
 * 4. If the managed install fails, fall back to packaged resources/openclaw.
 */
export function getOpenClawDir(): string {
  return resolveOpenClawRuntime().dir;
}

export function reinstallManagedOpenClawRuntime(): OpenClawRuntimeResolution {
  cachedOpenClawRuntime = null;

  const bundledDir = getBundledOpenClawDir();
  const managedDir = getManagedOpenClawDir();
  rmSync(fsPath(managedDir), { recursive: true, force: true });

  let installedFromBundled = false;
  if (isValidOpenClawPackageDir(bundledDir)) {
    installedFromBundled = installBundledOpenClawToManagedRuntime(bundledDir, managedDir);
  }

  cachedOpenClawRuntime = {
    dir: hasRequiredOpenClawContextModules(managedDir) ? managedDir : bundledDir,
    source: hasRequiredOpenClawContextModules(managedDir) ? 'managed' : isValidOpenClawPackageDir(bundledDir) ? 'bundled' : 'missing',
    version: readOpenClawVersion(hasRequiredOpenClawContextModules(managedDir) ? managedDir : bundledDir),
    bundledDir,
    managedDir,
    installedFromBundled,
  };
  logOpenClawRuntime('[openclaw-runtime] Reinstalled managed OpenClaw runtime for first-run initialization', cachedOpenClawRuntime);
  return cachedOpenClawRuntime;
}

/**
 * Get OpenClaw package directory resolved to a real path.
 * Useful when consumers need deterministic module resolution under pnpm symlinks.
 */
export function getOpenClawResolvedDir(): string {
  const dir = getOpenClawDir();
  if (!existsSync(dir)) {
    return dir;
  }
  try {
    return realpathSync(dir);
  } catch {
    return dir;
  }
}

/**
 * Get OpenClaw entry script path (openclaw.mjs)
 */
export function getOpenClawEntryPath(): string {
  return join(getOpenClawDir(), 'openclaw.mjs');
}

/**
 * Get ClawHub CLI entry script path (clawdhub.js)
 */
export function getClawHubCliEntryPath(): string {
  return join(getElectronApp().getAppPath(), 'node_modules', 'clawhub', 'bin', 'clawdhub.js');
}

/**
 * Get ClawHub CLI binary path (node_modules/.bin)
 */
export function getClawHubCliBinPath(): string {
  const binName = process.platform === 'win32' ? 'clawhub.cmd' : 'clawhub';
  return join(getElectronApp().getAppPath(), 'node_modules', '.bin', binName);
}

/**
 * Check if OpenClaw package exists
 */
export function isOpenClawPresent(): boolean {
  const dir = getOpenClawDir();
  const pkgJsonPath = join(dir, 'package.json');
  return existsSync(dir) && existsSync(pkgJsonPath);
}

/**
 * Check if OpenClaw is built (has dist folder)
 * For the npm package, this should always be true since npm publishes the built dist.
 */
export function isOpenClawBuilt(): boolean {
  const dir = getOpenClawDir();
  const distDir = join(dir, 'dist');
  const hasDist = existsSync(distDir);
  return hasDist;
}

/**
 * Get OpenClaw status for environment check
 */
export interface OpenClawStatus {
  packageExists: boolean;
  isBuilt: boolean;
  entryPath: string;
  dir: string;
  version?: string;
  source?: OpenClawRuntimeSource;
  bundledDir?: string;
  managedDir?: string;
  installedFromBundled?: boolean;
}

export function getOpenClawStatus(): OpenClawStatus {
  const runtime = resolveOpenClawRuntime();
  const dir = runtime.dir;

  const status: OpenClawStatus = {
    packageExists: isOpenClawPresent(),
    isBuilt: isOpenClawBuilt(),
    entryPath: getOpenClawEntryPath(),
    dir,
    version: runtime.version,
    source: runtime.source,
    bundledDir: runtime.bundledDir,
    managedDir: runtime.managedDir,
    installedFromBundled: runtime.installedFromBundled,
  };

  try {
    const { logger } = require('./logger') as typeof import('./logger');
    logger.info('OpenClaw status:', status);
  } catch {
    // Ignore logger bootstrap issues in non-Electron contexts such as unit tests.
  }
  return status;
}