/**
 * Electron main process (TypeScript)
 *
 * This version spawns the backend server and uses HTTP API for most operations.
 * Only native features (dialogs, shell) use IPC.
 */

import path from 'path';
import { spawn, ChildProcess } from 'child_process';
import fs from 'fs';
import http, { Server } from 'http';
import { app, BrowserWindow, ipcMain, dialog, shell, screen } from 'electron';
import { findNodeExecutable, buildEnhancedPath } from '@automaker/platform';

// Development environment
const isDev = !app.isPackaged;
const VITE_DEV_SERVER_URL = process.env.VITE_DEV_SERVER_URL;

// Load environment variables from .env file (development only)
if (isDev) {
  try {
    // eslint-disable-next-line @typescript-eslint/no-require-imports
    require('dotenv').config({ path: path.join(__dirname, '../.env') });
  } catch (error) {
    console.warn('[Electron] dotenv not available:', (error as Error).message);
  }
}

let mainWindow: BrowserWindow | null = null;
let serverProcess: ChildProcess | null = null;
let staticServer: Server | null = null;
const SERVER_PORT = 3008;
const STATIC_PORT = 3007;

// ============================================
// Window sizing constants for kanban layout
// ============================================
// Calculation: 4 columns × 280px + 3 gaps × 20px + 40px padding = 1220px board content
// With sidebar expanded (288px): 1220 + 288 = 1508px
// With sidebar collapsed (64px): 1220 + 64 = 1284px
const COLUMN_MIN_WIDTH = 280;
const COLUMN_COUNT = 4;
const GAP_SIZE = 20;
const BOARD_PADDING = 40; // px-5 on both sides = 40px (matches gap between columns)
const SIDEBAR_EXPANDED = 288;
const SIDEBAR_COLLAPSED = 64;

const BOARD_CONTENT_MIN =
  COLUMN_MIN_WIDTH * COLUMN_COUNT + GAP_SIZE * (COLUMN_COUNT - 1) + BOARD_PADDING;
const MIN_WIDTH_EXPANDED = BOARD_CONTENT_MIN + SIDEBAR_EXPANDED; // 1500px
const MIN_WIDTH_COLLAPSED = BOARD_CONTENT_MIN + SIDEBAR_COLLAPSED; // 1276px
const MIN_HEIGHT = 650; // Ensures sidebar content fits without scrolling
const DEFAULT_WIDTH = 1600;
const DEFAULT_HEIGHT = 950;

// Window bounds interface (matches @automaker/types WindowBounds)
interface WindowBounds {
  x: number;
  y: number;
  width: number;
  height: number;
  isMaximized: boolean;
}

// Debounce timer for saving window bounds
let saveWindowBoundsTimeout: ReturnType<typeof setTimeout> | null = null;

/**
 * Get icon path - works in both dev and production, cross-platform
 */
function getIconPath(): string | null {
  let iconFile: string;
  if (process.platform === 'win32') {
    iconFile = 'icon.ico';
  } else if (process.platform === 'darwin') {
    iconFile = 'logo_larger.png';
  } else {
    iconFile = 'logo_larger.png';
  }

  const iconPath = isDev
    ? path.join(__dirname, '../public', iconFile)
    : path.join(__dirname, '../dist/public', iconFile);

  if (!fs.existsSync(iconPath)) {
    console.warn(`[Electron] Icon not found at: ${iconPath}`);
    return null;
  }

  return iconPath;
}

/**
 * Get path to window bounds settings file
 */
function getWindowBoundsPath(): string {
  return path.join(app.getPath('userData'), 'window-bounds.json');
}

/**
 * Load saved window bounds from disk
 */
function loadWindowBounds(): WindowBounds | null {
  try {
    const boundsPath = getWindowBoundsPath();
    if (fs.existsSync(boundsPath)) {
      const data = fs.readFileSync(boundsPath, 'utf-8');
      const bounds = JSON.parse(data) as WindowBounds;
      // Validate the loaded data has required fields
      if (
        typeof bounds.x === 'number' &&
        typeof bounds.y === 'number' &&
        typeof bounds.width === 'number' &&
        typeof bounds.height === 'number'
      ) {
        return bounds;
      }
    }
  } catch (error) {
    console.warn('[Electron] Failed to load window bounds:', (error as Error).message);
  }
  return null;
}

/**
 * Save window bounds to disk
 */
function saveWindowBounds(bounds: WindowBounds): void {
  try {
    const boundsPath = getWindowBoundsPath();
    fs.writeFileSync(boundsPath, JSON.stringify(bounds, null, 2), 'utf-8');
    console.log('[Electron] Window bounds saved');
  } catch (error) {
    console.warn('[Electron] Failed to save window bounds:', (error as Error).message);
  }
}

/**
 * Schedule a debounced save of window bounds (500ms delay)
 */
function scheduleSaveWindowBounds(): void {
  if (!mainWindow || mainWindow.isDestroyed()) return;

  if (saveWindowBoundsTimeout) {
    clearTimeout(saveWindowBoundsTimeout);
  }

  saveWindowBoundsTimeout = setTimeout(() => {
    if (!mainWindow || mainWindow.isDestroyed()) return;

    const isMaximized = mainWindow.isMaximized();
    // Use getNormalBounds() for maximized windows to save pre-maximized size
    const bounds = isMaximized ? mainWindow.getNormalBounds() : mainWindow.getBounds();

    saveWindowBounds({
      x: bounds.x,
      y: bounds.y,
      width: bounds.width,
      height: bounds.height,
      isMaximized,
    });
  }, 500);
}

/**
 * Validate that window bounds are visible on at least one display
 * Returns adjusted bounds if needed, or null if completely off-screen
 */
function validateBounds(bounds: WindowBounds): WindowBounds {
  const displays = screen.getAllDisplays();

  // Check if window center is visible on any display
  const centerX = bounds.x + bounds.width / 2;
  const centerY = bounds.y + bounds.height / 2;

  let isVisible = false;
  for (const display of displays) {
    const { x, y, width, height } = display.workArea;
    if (centerX >= x && centerX <= x + width && centerY >= y && centerY <= y + height) {
      isVisible = true;
      break;
    }
  }

  if (!isVisible) {
    // Window is off-screen, reset to primary display
    const primaryDisplay = screen.getPrimaryDisplay();
    const { x, y, width, height } = primaryDisplay.workArea;

    return {
      x: x + Math.floor((width - bounds.width) / 2),
      y: y + Math.floor((height - bounds.height) / 2),
      width: Math.min(bounds.width, width),
      height: Math.min(bounds.height, height),
      isMaximized: bounds.isMaximized,
    };
  }

  // Ensure minimum dimensions
  return {
    ...bounds,
    width: Math.max(bounds.width, MIN_WIDTH_EXPANDED),
    height: Math.max(bounds.height, MIN_HEIGHT),
  };
}

/**
 * Start static file server for production builds
 */
async function startStaticServer(): Promise<void> {
  const staticPath = path.join(__dirname, '../dist');

  staticServer = http.createServer((request, response) => {
    let filePath = path.join(staticPath, request.url?.split('?')[0] || '/');

    if (filePath.endsWith('/')) {
      filePath = path.join(filePath, 'index.html');
    } else if (!path.extname(filePath)) {
      // For client-side routing, serve index.html for paths without extensions
      const possibleFile = filePath + '.html';
      if (!fs.existsSync(filePath) && !fs.existsSync(possibleFile)) {
        filePath = path.join(staticPath, 'index.html');
      } else if (fs.existsSync(possibleFile)) {
        filePath = possibleFile;
      }
    }

    fs.stat(filePath, (err, stats) => {
      if (err || !stats?.isFile()) {
        filePath = path.join(staticPath, 'index.html');
      }

      fs.readFile(filePath, (error, content) => {
        if (error) {
          response.writeHead(500);
          response.end('Server Error');
          return;
        }

        const ext = path.extname(filePath);
        const contentTypes: Record<string, string> = {
          '.html': 'text/html',
          '.js': 'application/javascript',
          '.css': 'text/css',
          '.json': 'application/json',
          '.png': 'image/png',
          '.jpg': 'image/jpeg',
          '.gif': 'image/gif',
          '.svg': 'image/svg+xml',
          '.ico': 'image/x-icon',
          '.woff': 'font/woff',
          '.woff2': 'font/woff2',
          '.ttf': 'font/ttf',
          '.eot': 'application/vnd.ms-fontobject',
        };

        response.writeHead(200, {
          'Content-Type': contentTypes[ext] || 'application/octet-stream',
        });
        response.end(content);
      });
    });
  });

  return new Promise((resolve, reject) => {
    staticServer!.listen(STATIC_PORT, () => {
      console.log(`[Electron] Static server running at http://localhost:${STATIC_PORT}`);
      resolve();
    });
    staticServer!.on('error', reject);
  });
}

/**
 * Start the backend server
 */
async function startServer(): Promise<void> {
  // Find Node.js executable (handles desktop launcher scenarios)
  const nodeResult = findNodeExecutable({
    skipSearch: isDev,
    logger: (msg: string) => console.log(`[Electron] ${msg}`),
  });
  const command = nodeResult.nodePath;

  // Validate that the found Node executable actually exists
  if (command !== 'node' && !fs.existsSync(command)) {
    throw new Error(`Node.js executable not found at: ${command} (source: ${nodeResult.source})`);
  }

  let args: string[];
  let serverPath: string;

  if (isDev) {
    serverPath = path.join(__dirname, '../../server/src/index.ts');

    const serverNodeModules = path.join(__dirname, '../../server/node_modules/tsx');
    const rootNodeModules = path.join(__dirname, '../../../node_modules/tsx');

    let tsxCliPath: string;
    if (fs.existsSync(path.join(serverNodeModules, 'dist/cli.mjs'))) {
      tsxCliPath = path.join(serverNodeModules, 'dist/cli.mjs');
    } else if (fs.existsSync(path.join(rootNodeModules, 'dist/cli.mjs'))) {
      tsxCliPath = path.join(rootNodeModules, 'dist/cli.mjs');
    } else {
      try {
        tsxCliPath = require.resolve('tsx/cli.mjs', {
          paths: [path.join(__dirname, '../../server')],
        });
      } catch {
        throw new Error("Could not find tsx. Please run 'npm install' in the server directory.");
      }
    }

    args = [tsxCliPath, 'watch', serverPath];
  } else {
    serverPath = path.join(process.resourcesPath, 'server', 'index.js');
    args = [serverPath];

    if (!fs.existsSync(serverPath)) {
      throw new Error(`Server not found at: ${serverPath}`);
    }
  }

  const serverNodeModules = app.isPackaged
    ? path.join(process.resourcesPath, 'server', 'node_modules')
    : path.join(__dirname, '../../server/node_modules');

  // Build enhanced PATH that includes Node.js directory (cross-platform)
  const enhancedPath = buildEnhancedPath(command, process.env.PATH || '');
  if (enhancedPath !== process.env.PATH) {
    console.log(`[Electron] Enhanced PATH with Node directory: ${path.dirname(command)}`);
  }

  const env = {
    ...process.env,
    PATH: enhancedPath,
    PORT: SERVER_PORT.toString(),
    DATA_DIR: app.getPath('userData'),
    NODE_PATH: serverNodeModules,
    // Only set ALLOWED_ROOT_DIRECTORY if explicitly provided in environment
    // If not set, server will allow access to all paths
    ...(process.env.ALLOWED_ROOT_DIRECTORY && {
      ALLOWED_ROOT_DIRECTORY: process.env.ALLOWED_ROOT_DIRECTORY,
    }),
  };

  console.log('[Electron] Starting backend server...');
  console.log('[Electron] Server path:', serverPath);
  console.log('[Electron] NODE_PATH:', serverNodeModules);

  serverProcess = spawn(command, args, {
    cwd: path.dirname(serverPath),
    env,
    stdio: ['ignore', 'pipe', 'pipe'],
  });

  serverProcess.stdout?.on('data', (data) => {
    console.log(`[Server] ${data.toString().trim()}`);
  });

  serverProcess.stderr?.on('data', (data) => {
    console.error(`[Server Error] ${data.toString().trim()}`);
  });

  serverProcess.on('close', (code) => {
    console.log(`[Server] Process exited with code ${code}`);
    serverProcess = null;
  });

  serverProcess.on('error', (err) => {
    console.error(`[Server] Failed to start server process:`, err);
    serverProcess = null;
  });

  await waitForServer();
}

/**
 * Wait for server to be available
 */
async function waitForServer(maxAttempts = 30): Promise<void> {
  for (let i = 0; i < maxAttempts; i++) {
    try {
      await new Promise<void>((resolve, reject) => {
        const req = http.get(`http://localhost:${SERVER_PORT}/api/health`, (res) => {
          if (res.statusCode === 200) {
            resolve();
          } else {
            reject(new Error(`Status: ${res.statusCode}`));
          }
        });
        req.on('error', reject);
        req.setTimeout(1000, () => {
          req.destroy();
          reject(new Error('Timeout'));
        });
      });
      console.log('[Electron] Server is ready');
      return;
    } catch {
      await new Promise((r) => setTimeout(r, 500));
    }
  }

  throw new Error('Server failed to start');
}

/**
 * Create the main window
 */
function createWindow(): void {
  const iconPath = getIconPath();

  // Load and validate saved window bounds
  const savedBounds = loadWindowBounds();
  const validBounds = savedBounds ? validateBounds(savedBounds) : null;

  const windowOptions: Electron.BrowserWindowConstructorOptions = {
    width: validBounds?.width ?? DEFAULT_WIDTH,
    height: validBounds?.height ?? DEFAULT_HEIGHT,
    x: validBounds?.x,
    y: validBounds?.y,
    minWidth: MIN_WIDTH_EXPANDED, // 1500px - ensures kanban columns fit with sidebar
    minHeight: MIN_HEIGHT,
    webPreferences: {
      preload: path.join(__dirname, 'preload.js'),
      contextIsolation: true,
      nodeIntegration: false,
    },
    titleBarStyle: 'hiddenInset',
    backgroundColor: '#0a0a0a',
  };

  if (iconPath) {
    windowOptions.icon = iconPath;
  }

  mainWindow = new BrowserWindow(windowOptions);

  // Restore maximized state if previously maximized
  if (validBounds?.isMaximized) {
    mainWindow.maximize();
  }

  // Load Vite dev server in development or static server in production
  if (VITE_DEV_SERVER_URL) {
    mainWindow.loadURL(VITE_DEV_SERVER_URL);
  } else if (isDev) {
    // Fallback for dev without Vite server URL
    mainWindow.loadURL(`http://localhost:${STATIC_PORT}`);
  } else {
    mainWindow.loadURL(`http://localhost:${STATIC_PORT}`);
  }

  if (isDev && process.env.OPEN_DEVTOOLS === 'true') {
    mainWindow.webContents.openDevTools();
  }

  // Save window bounds on close, resize, and move
  mainWindow.on('close', () => {
    // Save immediately before closing (not debounced)
    if (mainWindow && !mainWindow.isDestroyed()) {
      const isMaximized = mainWindow.isMaximized();
      const bounds = isMaximized ? mainWindow.getNormalBounds() : mainWindow.getBounds();

      saveWindowBounds({
        x: bounds.x,
        y: bounds.y,
        width: bounds.width,
        height: bounds.height,
        isMaximized,
      });
    }
  });

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

  mainWindow.on('resized', () => {
    scheduleSaveWindowBounds();
  });

  mainWindow.on('moved', () => {
    scheduleSaveWindowBounds();
  });

  mainWindow.webContents.setWindowOpenHandler(({ url }) => {
    shell.openExternal(url);
    return { action: 'deny' };
  });
}

// App lifecycle
app.whenReady().then(async () => {
  // Ensure userData path is consistent across dev/prod so files land in Automaker dir
  try {
    const desiredUserDataPath = path.join(app.getPath('appData'), 'Automaker');
    if (app.getPath('userData') !== desiredUserDataPath) {
      app.setPath('userData', desiredUserDataPath);
      console.log('[Electron] userData path set to:', desiredUserDataPath);
    }
  } catch (error) {
    console.warn('[Electron] Failed to set userData path:', (error as Error).message);
  }

  if (process.platform === 'darwin' && app.dock) {
    const iconPath = getIconPath();
    if (iconPath) {
      try {
        app.dock.setIcon(iconPath);
      } catch (error) {
        console.warn('[Electron] Failed to set dock icon:', (error as Error).message);
      }
    }
  }

  try {
    // Start static file server in production
    if (app.isPackaged) {
      await startStaticServer();
    }

    // Start backend server
    await startServer();

    // Create window
    createWindow();
  } catch (error) {
    console.error('[Electron] Failed to start:', error);
    const errorMessage = (error as Error).message;
    const isNodeError = errorMessage.includes('Node.js');
    dialog.showErrorBox(
      'Automaker Failed to Start',
      `The application failed to start.\n\n${errorMessage}\n\n${
        isNodeError
          ? 'Please install Node.js from https://nodejs.org or via a package manager (Homebrew, nvm, fnm).'
          : 'Please check the application logs for more details.'
      }`
    );
    app.quit();
  }

  app.on('activate', () => {
    if (BrowserWindow.getAllWindows().length === 0) {
      createWindow();
    }
  });
});

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

app.on('before-quit', () => {
  if (serverProcess) {
    console.log('[Electron] Stopping server...');
    serverProcess.kill();
    serverProcess = null;
  }

  if (staticServer) {
    console.log('[Electron] Stopping static server...');
    staticServer.close();
    staticServer = null;
  }
});

// ============================================
// IPC Handlers - Only native features
// ============================================

// Native file dialogs
ipcMain.handle('dialog:openDirectory', async () => {
  if (!mainWindow) {
    return { canceled: true, filePaths: [] };
  }
  const result = await dialog.showOpenDialog(mainWindow, {
    properties: ['openDirectory', 'createDirectory'],
  });
  return result;
});

ipcMain.handle('dialog:openFile', async (_, options = {}) => {
  if (!mainWindow) {
    return { canceled: true, filePaths: [] };
  }
  const result = await dialog.showOpenDialog(mainWindow, {
    properties: ['openFile'],
    ...options,
  });
  return result;
});

ipcMain.handle('dialog:saveFile', async (_, options = {}) => {
  if (!mainWindow) {
    return { canceled: true, filePath: undefined };
  }
  const result = await dialog.showSaveDialog(mainWindow, options);
  return result;
});

// Shell operations
ipcMain.handle('shell:openExternal', async (_, url: string) => {
  try {
    await shell.openExternal(url);
    return { success: true };
  } catch (error) {
    return { success: false, error: (error as Error).message };
  }
});

ipcMain.handle('shell:openPath', async (_, filePath: string) => {
  try {
    await shell.openPath(filePath);
    return { success: true };
  } catch (error) {
    return { success: false, error: (error as Error).message };
  }
});

// Open file in editor (VS Code, etc.) with optional line/column
ipcMain.handle(
  'shell:openInEditor',
  async (_, filePath: string, line?: number, column?: number) => {
    try {
      // Build VS Code URL scheme: vscode://file/path:line:column
      // This works on all platforms where VS Code is installed
      // URL encode the path to handle special characters (spaces, brackets, etc.)
      // Handle both Unix (/) and Windows (\) path separators
      const normalizedPath = filePath.replace(/\\/g, '/');
      const encodedPath = normalizedPath.startsWith('/')
        ? '/' + normalizedPath.slice(1).split('/').map(encodeURIComponent).join('/')
        : normalizedPath.split('/').map(encodeURIComponent).join('/');
      let url = `vscode://file${encodedPath}`;
      if (line !== undefined && line > 0) {
        url += `:${line}`;
        if (column !== undefined && column > 0) {
          url += `:${column}`;
        }
      }
      await shell.openExternal(url);
      return { success: true };
    } catch (error) {
      return { success: false, error: (error as Error).message };
    }
  }
);

// App info
ipcMain.handle('app:getPath', async (_, name: Parameters<typeof app.getPath>[0]) => {
  return app.getPath(name);
});

ipcMain.handle('app:getVersion', async () => {
  return app.getVersion();
});

ipcMain.handle('app:isPackaged', async () => {
  return app.isPackaged;
});

// Ping - for connection check
ipcMain.handle('ping', async () => {
  return 'pong';
});

// Get server URL for HTTP client
ipcMain.handle('server:getUrl', async () => {
  return `http://localhost:${SERVER_PORT}`;
});

// Window management - update minimum width based on sidebar state
ipcMain.handle('window:updateMinWidth', (_, sidebarExpanded: boolean) => {
  if (!mainWindow || mainWindow.isDestroyed()) return;

  const minWidth = sidebarExpanded ? MIN_WIDTH_EXPANDED : MIN_WIDTH_COLLAPSED;
  mainWindow.setMinimumSize(minWidth, MIN_HEIGHT);

  // If current width is below new minimum, resize window
  const currentBounds = mainWindow.getBounds();
  if (currentBounds.width < minWidth) {
    mainWindow.setSize(minWidth, currentBounds.height);
  }
});