/**
 * Electron Main Process Entry
 * Manages window creation, system tray, and IPC handlers
 */
import { app, BrowserWindow, nativeImage, shell } from 'electron';
import type { Server } from 'node:http';
import { join } from 'path';
import { OpencodeManager } from '../opencode/manager';
import { buildOpencodeRuntimeConfigFromNianCodeProviders } from '../opencode/provider-config';
import {
  PLAYWRIGHT_MCP_SERVER_ID,
  resolvePlaywrightMcpServer,
} from '../opencode/playwright-mcp';
import { resolveOpencodeRuntimePaths } from '../opencode/paths';
import {
  resolveBundledCourseSkillsDir,
  resolveBundledSuperpowersDir,
} from '../opencode/superpowers';
import {
  createElectronProjectStorage,
  createProjectStore,
  type OpencodeProjectStore,
} from '../opencode/project-store';
import { registerIpcHandlers } from './ipc-handlers';
import { createTray } from './tray';
import { createMenu } from './menu';
import { registerZoomShortcuts } from './zoom-shortcuts';

import { appUpdater, registerUpdateHandlers } from './updater';
import { logger } from '../utils/logger';
import { warmupNetworkOptimization } from '../utils/uv-env';
import { resolvePythonRuntime } from '../utils/python-runtime';
import { initTelemetry } from '../utils/telemetry';

import { isQuitting, setQuitting } from './app-state';
import { applyProxySettings } from './proxy';
import { syncLaunchAtStartupSettingFromStore } from './launch-at-startup';
import {
  clearPendingSecondInstanceFocus,
  consumeMainWindowReady,
  createMainWindowFocusState,
  requestSecondInstanceFocus,
} from './main-window-focus';
import {
  findNianCodeDeepLinkUrl,
  NIANCODE_APP_PROTOCOL,
  parseNianCodeDeepLinkUrl,
} from './app-deep-link';
import { installMediaPermissionHandler } from './media-permissions';
import {
  createQuitLifecycleState,
  markQuitCleanupCompleted,
  requestQuitLifecycleAction,
} from './quit-lifecycle';
import {
  executableSnapshotChanged,
  snapshotExecutable,
} from './relaunch-on-replaced-app';
import { createSignalQuitHandler } from './signal-quit';
import { acquireProcessInstanceFileLock } from './process-instance-lock';

import { getHostApiToken, startHostApiServer } from '../api/server';
import { HostEventBus } from '../api/event-bus';
import { browserOAuthManager } from '../utils/browser-oauth';
import { createProjectProgressSync } from '../services/project-progress-sync';
import { createWorksCloudDeployment } from '../services/works-cloud-deployment';
import { getPort } from '../utils/config';
import { initializeMeowaGameAssetsCredential } from '../api/routes/meowa-game-assets';
import {
  isLocalImageWorkspaceDevelopmentEnabled,
  LocalImageWorkspace,
} from '../image-workspace/local-workspace';
import { WorksSquareDesignWorkspace } from '../image-workspace/works-square-workspace';

const WINDOWS_APP_USER_MODEL_ID = 'app.niancode.desktop';
const isE2EMode = process.env.NIANCODE_E2E === '1';
const requestedUserDataDir = process.env.NIANCODE_USER_DATA_DIR?.trim();

if (isE2EMode && requestedUserDataDir) {
  app.setPath('userData', requestedUserDataDir);
}

// Disable GPU hardware acceleration globally for maximum stability across
// all GPU configurations (no GPU, integrated, discrete).
//
// Rationale (following VS Code's philosophy):
// - Page/file loading is async data fetching — zero GPU dependency.
// - The original per-platform GPU branching was added to avoid CPU rendering
//   competing with sync I/O on Windows, but all file I/O is now async
//   (fs/promises), so that concern no longer applies.
// - Software rendering is deterministic across all hardware; GPU compositing
//   behaviour varies between vendors (Intel, AMD, NVIDIA, Apple Silicon) and
//   driver versions, making it the #1 source of rendering bugs in Electron.
//
// Users who want GPU acceleration can pass `--enable-gpu` on the CLI or
// set `"disable-hardware-acceleration": false` in the app config (future).
app.disableHardwareAcceleration();

// On Linux, set CHROME_DESKTOP so Chromium can find the correct .desktop file.
// On Wayland this maps the running window to niancode.desktop (→ icon + app grouping);
// on X11 it supplements the StartupWMClass matching.
// Must be called before app.whenReady() / before any window is created.
if (process.platform === 'linux') {
  app.setDesktopName('niancode.desktop');
}

// Prevent multiple instances of the app from running simultaneously.
// Without this, two instances can each spawn their own local runtime process on
// the same port. The losing process must exit immediately.
const gotElectronLock = isE2EMode ? true : app.requestSingleInstanceLock();
if (!gotElectronLock) {
  console.info('[Makelore] Another instance already holds the single-instance lock; exiting duplicate process');
  app.exit(0);
}
let releaseProcessInstanceFileLock: () => void = () => {};
let gotFileLock = true;
if (gotElectronLock && !isE2EMode) {
  try {
    const fileLock = acquireProcessInstanceFileLock({
      userDataDir: app.getPath('userData'),
      lockName: 'niancode',
      force: true, // Electron lock already guarantees exclusivity; force-clean orphan/recycled-PID locks
    });
    gotFileLock = fileLock.acquired;
    releaseProcessInstanceFileLock = fileLock.release;
    if (!fileLock.acquired) {
      const ownerDescriptor = fileLock.ownerPid
        ? `${fileLock.ownerFormat ?? 'legacy'} pid=${fileLock.ownerPid}`
        : fileLock.ownerFormat === 'unknown'
          ? 'unknown lock format/content'
          : 'unknown owner';
      console.info(
        `[Makelore] Another instance already holds process lock (${fileLock.lockPath}, ${ownerDescriptor}); exiting duplicate process`,
      );
      app.exit(0);
    }
  } catch (error) {
    console.warn('[Makelore] Failed to acquire process instance file lock; continuing with Electron single-instance lock only', error);
  }
}
const gotTheLock = gotElectronLock && gotFileLock;
const executableSnapshotAtLaunch = snapshotExecutable(process.execPath);

// Global references
let mainWindow: BrowserWindow | null = null;
let opencodeManager!: OpencodeManager;
let opencodeProjectStore!: OpencodeProjectStore;
let hostEventBus!: HostEventBus;
let hostApiServer: Server | null = null;
let projectProgressSync: ReturnType<typeof createProjectProgressSync> | null = null;
let worksCloudDeployment: ReturnType<typeof createWorksCloudDeployment> | null = null;
const mainWindowFocusState = createMainWindowFocusState();
const quitLifecycleState = createQuitLifecycleState();
const launchDeepLinkUrl = findNianCodeDeepLinkUrl(process.argv);

/**
 * Resolve the icons directory path (works in both dev and packaged mode)
 */
function getIconsDir(): string {
  if (app.isPackaged) {
    // Packaged: icons are in extraResources → process.resourcesPath/resources/icons
    return join(process.resourcesPath, 'resources', 'icons');
  }
  // Development: relative to dist-electron/main/
  return join(__dirname, '../../resources/icons');
}

/**
 * Get the app icon for the current platform
 */
function getAppIcon(): Electron.NativeImage | undefined {
  if (process.platform === 'darwin') return undefined; // macOS uses the app bundle icon

  const iconsDir = getIconsDir();
  const iconPath =
    process.platform === 'win32'
      ? join(iconsDir, 'icon.ico')
      : join(iconsDir, 'icon.png');
  const icon = nativeImage.createFromPath(iconPath);
  return icon.isEmpty() ? undefined : icon;
}

/**
 * Create the main application window
 */
function createWindow(): BrowserWindow {
  const isMac = process.platform === 'darwin';
  const isWindows = process.platform === 'win32';
  const useCustomTitleBar = isWindows;
  const shouldSkipSetupForE2E = process.env.NIANCODE_E2E_SKIP_SETUP === '1';

  const win = new BrowserWindow({
    title: 'Makelore',
    width: 1280,
    height: 800,
    minWidth: 1100,
    minHeight: 700,
    icon: getAppIcon(),
    webPreferences: {
      preload: join(__dirname, '../preload/index.js'),
      nodeIntegration: false,
      contextIsolation: true,
      sandbox: false,
      webviewTag: false,
    },
    titleBarStyle: isMac ? 'hiddenInset' : useCustomTitleBar ? 'hidden' : 'default',
    trafficLightPosition: isMac ? { x: 16, y: 16 } : undefined,
    frame: isMac || !useCustomTitleBar,
    show: false,
  });

  installMediaPermissionHandler(win);
  registerZoomShortcuts(win);

  // Handle external links — only allow safe protocols to prevent arbitrary
  // command execution via shell.openExternal() (e.g. file://, ms-msdt:, etc.)
  win.webContents.setWindowOpenHandler(({ url }) => {
    try {
      const parsed = new URL(url);
      if (parsed.protocol === 'https:' || parsed.protocol === 'http:') {
        shell.openExternal(url);
      } else {
        logger.warn(`Blocked openExternal for disallowed protocol: ${parsed.protocol}`);
      }
    } catch {
      logger.warn(`Blocked openExternal for malformed URL: ${url}`);
    }
    return { action: 'deny' };
  });

  // Load the app
  if (process.env.VITE_DEV_SERVER_URL) {
    const rendererUrl = new URL(process.env.VITE_DEV_SERVER_URL);
    if (shouldSkipSetupForE2E) {
      rendererUrl.searchParams.set('e2eSkipSetup', '1');
    }
    win.loadURL(rendererUrl.toString());
    if (!isE2EMode) {
      win.webContents.openDevTools();
    }
  } else {
    win.loadFile(join(__dirname, '../../dist/index.html'), {
      query: shouldSkipSetupForE2E
        ? { e2eSkipSetup: '1' }
        : undefined,
    });
  }

  return win;
}

function focusWindow(win: BrowserWindow): void {
  if (win.isDestroyed()) {
    return;
  }

  if (win.isMinimized()) {
    win.restore();
  }

  win.show();
  win.focus();
}

function focusMainWindow(): void {
  if (!mainWindow || mainWindow.isDestroyed()) {
    return;
  }

  clearPendingSecondInstanceFocus(mainWindowFocusState);
  focusWindow(mainWindow);
}

function requestMainWindowFocus(reason: string): void {
  const focusRequest = requestSecondInstanceFocus(
    mainWindowFocusState,
    Boolean(mainWindow && !mainWindow.isDestroyed()),
  );

  if (focusRequest === 'focus-now') {
    focusMainWindow();
    return;
  }

  logger.debug(`Main window is not ready yet; deferring focus for ${reason}`);
}

function handleAppDeepLinkActivation(rawUrl: string): boolean {
  const deepLink = parseNianCodeDeepLinkUrl(rawUrl);
  if (!deepLink) {
    return false;
  }

  logger.info(`Received Makelore app link: type=${deepLink.type}, request_id=${deepLink.requestId}`);
  requestMainWindowFocus('app deep link');
  return true;
}

function registerMakeloreProtocolClient(): void {
  const devEntrypoint = app.isPackaged ? undefined : process.argv[1];
  const registered = devEntrypoint
    ? app.setAsDefaultProtocolClient(NIANCODE_APP_PROTOCOL, process.execPath, [devEntrypoint])
    : app.setAsDefaultProtocolClient(NIANCODE_APP_PROTOCOL);

  if (!registered) {
    logger.warn(`Failed to register ${NIANCODE_APP_PROTOCOL}:// protocol handler`);
  }
}

function createMainWindow(): BrowserWindow {
  const win = createWindow();

  win.once('ready-to-show', () => {
    if (mainWindow !== win) {
      return;
    }

    const action = consumeMainWindowReady(mainWindowFocusState);
    if (action === 'focus') {
      focusWindow(win);
      return;
    }

    win.show();
  });

  win.on('close', (event) => {
    if (!isQuitting() && !isE2EMode) {
      event.preventDefault();
      win.hide();
    }
  });

  win.on('closed', () => {
    if (mainWindow === win) {
      mainWindow = null;
    }
  });

  mainWindow = win;
  return win;
}

/**
 * Initialize the application
 */
async function initialize(): Promise<void> {
  // Initialize logger first
  logger.init();
  logger.info('=== Makelore Application Starting ===');
  logger.debug(
    `Runtime: platform=${process.platform}/${process.arch}, electron=${process.versions.electron}, node=${process.versions.node}, packaged=${app.isPackaged}, pid=${process.pid}, ppid=${process.ppid}`
  );

  if (!isE2EMode) {
    registerMakeloreProtocolClient();
  }

  if (launchDeepLinkUrl) {
    handleAppDeepLinkActivation(launchDeepLinkUrl);
  }

  if (!isE2EMode) {
    // Warm up network optimization (non-blocking)
    void warmupNetworkOptimization();

    // Initialize Telemetry early
    await initTelemetry();

    // Apply persisted proxy settings before creating windows or network requests.
    await applyProxySettings();
    const meowaCredential = await initializeMeowaGameAssetsCredential();
    if (meowaCredential.source !== 'none') {
      logger.info(`Meowa game-assets credential initialized via ${meowaCredential.source}`);
    }
    await syncLaunchAtStartupSettingFromStore();
  } else {
    logger.info('Running in E2E mode: startup side effects minimized');
  }

  opencodeProjectStore = createProjectStore(await createElectronProjectStorage());

  if (!isE2EMode) {
    projectProgressSync = createProjectProgressSync(opencodeProjectStore);
    void projectProgressSync.start();
  }
  worksCloudDeployment = createWorksCloudDeployment(opencodeProjectStore);
  if (!isE2EMode) void worksCloudDeployment.start();

  const localImageWorkspaceEnabled = isLocalImageWorkspaceDevelopmentEnabled({
    isPackaged: app.isPackaged,
    configuredMode: process.env.NIANCODE_IMAGE_WORKSPACE_MODE,
    isDevelopmentServer: Boolean(process.env.VITE_DEV_SERVER_URL),
  });
  const imageWorkspace = localImageWorkspaceEnabled
    ? new LocalImageWorkspace({ userDataDir: app.getPath('userData') })
    : new WorksSquareDesignWorkspace();
  if (localImageWorkspaceEnabled) {
    logger.info('AI painting workspace is using local development storage');
  } else {
    logger.info('AI painting workspace is using the Works Square cloud contract');
  }

  // Set application menu
  createMenu();

  // Create the main window
  const window = createMainWindow();

  // Create system tray
  if (!isE2EMode) {
    createTray(window);
  }

  // Register IPC handlers
  registerIpcHandlers(undefined, opencodeManager, undefined, window);

  hostApiServer = startHostApiServer({
    opencodeManager,
    opencodeProjectStore,
    eventBus: hostEventBus,
    mainWindow: window,
    worksCloudDeployment: worksCloudDeployment ?? undefined,
    imageWorkspace,
  });

  // Register update handlers
  registerUpdateHandlers(appUpdater, window);

  // Note: Auto-check for updates is driven by the renderer (update store init)
  // so it respects the user's "Auto-check for updates" setting.

  opencodeManager.on('status', (status) => {
    logger.info(
      `opencode runtime status: state=${status.state}, port=${status.port}, pid=${status.pid ?? 'n/a'}, url=${status.url ?? 'n/a'}${status.error ? `, error=${status.error}` : ''}`,
    );
    hostEventBus.emit('opencode:status', status);
  });

  opencodeManager.on('stderr', (message) => {
    const trimmed = message.trim();
    if (trimmed) {
      logger.warn(`[opencode stderr] ${trimmed}`);
    }
    hostEventBus.emit('opencode:stderr', { message });
  });

  browserOAuthManager.on('oauth:start', (payload) => {
    hostEventBus.emit('oauth:start', payload);
  });

  browserOAuthManager.on('oauth:code', (payload) => {
    hostEventBus.emit('oauth:code', payload);
  });

  browserOAuthManager.on('oauth:success', (payload) => {
    hostEventBus.emit('oauth:success', { ...payload, success: true });
  });

  browserOAuthManager.on('oauth:error', (error) => {
    hostEventBus.emit('oauth:error', error);
  });
}

if (gotTheLock) {
  const requestQuitOnSignal = createSignalQuitHandler({
    logInfo: (message) => logger.info(message),
    requestQuit: () => app.quit(),
  });

  process.on('exit', () => {
    releaseProcessInstanceFileLock();
  });

  process.once('SIGINT', () => requestQuitOnSignal('SIGINT'));
  process.once('SIGTERM', () => requestQuitOnSignal('SIGTERM'));

  app.on('will-quit', () => {
    releaseProcessInstanceFileLock();
  });

  if (process.platform === 'win32') {
    app.setAppUserModelId(WINDOWS_APP_USER_MODEL_ID);
  }

  const opencodePaths = resolveOpencodeRuntimePaths({
    isPackaged: app.isPackaged,
    resourcesPath: process.resourcesPath,
    appPath: app.getAppPath(),
    platform: process.platform,
    arch: process.arch,
  });
  const pythonRuntime = resolvePythonRuntime({
    isPackaged: app.isPackaged,
    resourcesPath: process.resourcesPath,
    appPath: app.getAppPath(),
    platform: process.platform,
    arch: process.arch,
    configuredPath: process.env.NIANCODE_PYTHON_PATH,
  });
  const bundledSuperpowersDir = resolveBundledSuperpowersDir({
    isPackaged: app.isPackaged,
    resourcesPath: process.resourcesPath,
    appPath: app.getAppPath(),
  });
  const bundledCourseSkillsDir = resolveBundledCourseSkillsDir({
    isPackaged: app.isPackaged,
    resourcesPath: process.resourcesPath,
    appPath: app.getAppPath(),
  });
  opencodeManager = new OpencodeManager({
    port: 4096,
    binPath: opencodePaths.binPath,
    userDataDir: app.getPath('userData'),
    bundledSuperpowersDir,
    bundledCourseSkillsDir,
    pythonRuntime,
    runtimeConfigProvider: async () => {
      const runtime = await buildOpencodeRuntimeConfigFromNianCodeProviders({
        mcpServers: {
          [PLAYWRIGHT_MCP_SERVER_ID]: resolvePlaywrightMcpServer(),
        },
      });
      return {
        ...runtime,
        config: runtime.config as unknown as Record<string, unknown>,
        env: {
          ...runtime.env,
          NIANCODE_HOST_API_BASE_URL: `http://127.0.0.1:${getPort('NIANCODE_HOST_API')}`,
          NIANCODE_HOST_API_TOKEN: getHostApiToken(),
        },
      };
    },
  });
  hostEventBus = new HostEventBus();

  // When a second instance is launched, focus the existing window instead.
  app.on('second-instance', (_event, commandLine) => {
    logger.info('Second Makelore instance detected; redirecting to the existing window');

    if (
      app.isPackaged
      && process.platform === 'darwin'
      && executableSnapshotChanged(executableSnapshotAtLaunch, snapshotExecutable(process.execPath))
    ) {
      logger.info('Detected that the installed app bundle changed while this instance was running; relaunching into the updated app');
      setQuitting();
      app.relaunch({ execPath: process.execPath });
      app.quit();
      return;
    }

    const deepLinkUrl = findNianCodeDeepLinkUrl(commandLine);
    if (deepLinkUrl && handleAppDeepLinkActivation(deepLinkUrl)) {
      return;
    }

    requestMainWindowFocus('second instance');
  });

  app.on('open-url', (event, url) => {
    event.preventDefault();
    if (!handleAppDeepLinkActivation(url)) {
      logger.warn('Ignored unsupported Makelore app link');
    }
  });

  // Application lifecycle
  app.whenReady().then(() => {
    void initialize().catch((error) => {
      logger.error('Application initialization failed:', error);
    });

    // Register activate handler AFTER app is ready to prevent
    // "Cannot create BrowserWindow before app is ready" on macOS.
    app.on('activate', () => {
      if (BrowserWindow.getAllWindows().length === 0) {
        createMainWindow();
      } else {
        focusMainWindow();
      }
    });
  });

  app.on('window-all-closed', () => {
    if (process.platform !== 'darwin' || isE2EMode) {
      app.quit();
    }
  });

  app.on('before-quit', (event) => {
    setQuitting();
    const action = requestQuitLifecycleAction(quitLifecycleState);

    if (action === 'allow-quit') {
      return;
    }

    event.preventDefault();

    if (action === 'cleanup-in-progress') {
      logger.debug('Quit requested while cleanup already in progress; waiting for shutdown task to finish');
      return;
    }

    hostEventBus.closeAll();
    hostApiServer?.close();
    projectProgressSync?.stop();
    worksCloudDeployment?.stop();

    const stopOpencodePromise = opencodeManager.stop().catch((err) => {
      logger.warn('opencodeManager.stop() error during quit:', err);
    });
    const stopPromise = Promise.allSettled([stopOpencodePromise]);
    const timeoutPromise = new Promise<'timeout'>((resolve) => {
      setTimeout(() => resolve('timeout'), 5000);
    });

    void Promise.race([stopPromise.then(() => 'stopped' as const), timeoutPromise]).then((result) => {
      if (result === 'timeout') {
        logger.warn('opencode shutdown timed out during app quit; proceeding with forced quit');
      }
      markQuitCleanupCompleted(quitLifecycleState);
      app.quit();
    });
  });

  // Best-effort runtime cleanup on unexpected crashes.
  // These handlers attempt to terminate the opencode child process within a
  // short timeout before force-exiting, preventing orphaned processes.
  const emergencyRuntimeCleanup = (reason: string, error: unknown): void => {
    logger.error(`${reason}:`, error);
    projectProgressSync?.stop();
    worksCloudDeployment?.stop();
    try {
      void opencodeManager?.stop().catch(() => { /* ignore */ });
    } catch {
      // ignore — stop() may not be callable if state is corrupted
    }
    // Give runtime stop a brief window, then force-exit.
    setTimeout(() => {
      process.exit(1);
    }, 3000).unref();
  };

  process.on('uncaughtException', (error) => {
    emergencyRuntimeCleanup('Uncaught exception in main process', error);
  });

  process.on('unhandledRejection', (reason) => {
    emergencyRuntimeCleanup('Unhandled promise rejection in main process', reason);
  });
}

// Export for testing
export { mainWindow, opencodeManager, opencodeProjectStore };