import { Request, Response } from 'express';
import { AuthService } from '../services/auth.service';
import { validateSSOCallback, validateRefreshToken, validateTokenExchange } from '../validators/auth.validator';
import { ResponseHandler } from '../utils/responseHandler';
import type { AuthenticatedRequest } from '../types/express';
import logger from '../utils/logger';

export class AuthController {
  private authService: AuthService;

  constructor() {
    this.authService = new AuthService();
  }

  /**
   * Handle SSO callback from frontend
   * POST /api/v1/auth/sso-callback
   */
  async handleSSOCallback(req: Request, res: Response): Promise<void> {
    try {
      // Validate request body
      const validatedData = validateSSOCallback(req.body);
      
      const result = await this.authService.handleSSOCallback(validatedData as any);
      
      ResponseHandler.success(res, {
        user: result.user,
        accessToken: result.accessToken,
        refreshToken: result.refreshToken
      }, 'Authentication successful');
    } catch (error) {
      logger.error('SSO callback failed:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      ResponseHandler.error(res, 'Authentication failed', 400, errorMessage);
    }
  }

  /**
   * Get current user profile
   * GET /api/v1/auth/me
   */
  async getCurrentUser(req: AuthenticatedRequest, res: Response): Promise<void> {
    try {
      const user = await this.authService.getUserProfile(req.user.userId);
      
      if (!user) {
        ResponseHandler.notFound(res, 'User not found');
        return;
      }

      ResponseHandler.success(res, {
        userId: user.userId,
        employeeId: user.employeeId,
        email: user.email,
        firstName: user.firstName,
        lastName: user.lastName,
        displayName: user.displayName,
        department: user.department,
        designation: user.designation,
        phone: user.phone,
        location: user.location,
        isAdmin: user.isAdmin,
        isActive: user.isActive,
        lastLogin: user.lastLogin,
        createdAt: user.createdAt,
        updatedAt: user.updatedAt
      }, 'User profile retrieved successfully');
    } catch (error) {
      logger.error('Failed to get current user:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      ResponseHandler.error(res, 'Failed to get user profile', 500, errorMessage);
    }
  }

  /**
   * Refresh access token
   * POST /api/v1/auth/refresh
   * Supports both request body and cookie-based refresh tokens
   */
  async refreshToken(req: Request, res: Response): Promise<void> {
    try {
      // Try to get refresh token from request body first, then from cookies
      let refreshToken: string;
      
      if (req.body?.refreshToken) {
        const validated = validateRefreshToken(req.body);
        refreshToken = validated.refreshToken;
      } else if ((req as any).cookies?.refreshToken) {
        // Fallback to cookie if available (requires cookie-parser middleware)
        refreshToken = (req as any).cookies.refreshToken;
      } else {
        throw new Error('Refresh token is required');
      }
      
      const newAccessToken = await this.authService.refreshAccessToken(refreshToken);
      
      // Set new access token in cookie if using cookie-based auth
      const isProduction = process.env.NODE_ENV === 'production';
      const cookieOptions = {
        httpOnly: true,
        secure: isProduction,
        sameSite: 'lax' as const,
        maxAge: 24 * 60 * 60 * 1000, // 24 hours
      };
      
      res.cookie('accessToken', newAccessToken, cookieOptions);
      
      ResponseHandler.success(res, {
        accessToken: newAccessToken
      }, 'Token refreshed successfully');
    } catch (error) {
      logger.error('Token refresh failed:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      ResponseHandler.error(res, 'Token refresh failed', 401, errorMessage);
    }
  }

  /**
   * Logout user
   * POST /api/v1/auth/logout
   * Clears all authentication cookies and tokens
   * IMPORTANT: Must use EXACT same cookie options as when setting cookies
   */
  async logout(req: Request, res: Response): Promise<void> {
    const isProduction = process.env.NODE_ENV === 'production';
    
    // Helper function to clear cookies with all possible option combinations
    const clearCookiesCompletely = () => {
      const cookieNames = ['accessToken', 'refreshToken'];
      
      // Get the EXACT options used when setting cookies (from exchangeToken)
      // These MUST match exactly: httpOnly, secure, sameSite, path
      const cookieOptions = {
        httpOnly: true,
        secure: isProduction,
        sameSite: 'lax' as const,
        path: '/',
      };

      logger.info('Attempting to clear cookies with options:', {
        httpOnly: cookieOptions.httpOnly,
        secure: cookieOptions.secure,
        sameSite: cookieOptions.sameSite,
        path: cookieOptions.path,
        isProduction,
      });

      // Method 1: Set expired cookie with exact same options
      // This is the most reliable method - sets cookie to expire immediately
      const expiredDate = new Date(0); // Jan 1, 1970
      cookieNames.forEach(name => {
        res.cookie(name, '', {
          httpOnly: cookieOptions.httpOnly,
          secure: cookieOptions.secure,
          sameSite: cookieOptions.sameSite,
          path: cookieOptions.path,
          expires: expiredDate,
          maxAge: 0,
        });
        logger.info(`Set expired cookie: ${name}`);
      });

      // Method 2: Use clearCookie with exact same options
      // clearCookie requires same options that were used to set the cookie
      cookieNames.forEach(name => {
        res.clearCookie(name, cookieOptions);
        logger.info(`Called clearCookie for: ${name}`);
      });

      // Method 3: Try without secure flag (for localhost/development)
      if (!isProduction) {
        cookieNames.forEach(name => {
          res.clearCookie(name, {
            httpOnly: true,
            secure: false,
            sameSite: 'lax',
            path: '/',
          });
        });
      }

      // Method 4: Try with all possible path variations
      const paths = ['/', '/api', '/api/v1'];
      paths.forEach(path => {
        cookieNames.forEach(name => {
          res.clearCookie(name, {
            httpOnly: true,
            secure: isProduction,
            sameSite: 'lax',
            path: path,
          });
        });
      });

      logger.info('Cookies clearing attempted with all methods', {
        cookieNames,
        isProduction,
        paths: ['/', '/api', '/api/v1'],
      });
    };

    try {
      // Logout should work even without authentication (to clear cookies)
      // User might be null if token was invalid/expired
      const userId = req.user?.userId || 'unknown';
      const email = req.user?.email || 'unknown';
      
      logger.info('User logout initiated', {
        userId,
        email,
        hasUser: !!req.user,
        hasCookies: !!req.cookies?.accessToken || !!req.cookies?.refreshToken,
        hasHeaderToken: !!req.headers.authorization,
      });

      // Clear all cookies using multiple methods
      clearCookiesCompletely();

      logger.info('User logout successful - cookies cleared', {
        userId: req.user?.userId || 'unknown',
        email: req.user?.email || 'unknown',
      });

      // Return success response
      ResponseHandler.success(res, { message: 'Logout successful, cookies cleared' }, 'Logout successful');
    } catch (error) {
      logger.error('Logout failed:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      
      // Even on error, try to clear cookies as last resort
      try {
        clearCookiesCompletely();
      } catch (cookieError) {
        logger.error('Error clearing cookies in catch block:', cookieError);
      }
      
      ResponseHandler.error(res, 'Logout failed', 500, errorMessage);
    }
  }

  /**
   * Validate token endpoint
   * GET /api/v1/auth/validate
   */
  async validateToken(req: AuthenticatedRequest, res: Response): Promise<void> {
    try {
      ResponseHandler.success(res, {
        valid: true,
        user: req.user
      }, 'Token is valid');
    } catch (error) {
      logger.error('Token validation failed:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      ResponseHandler.error(res, 'Token validation failed', 401, errorMessage);
    }
  }

  /**
   * Exchange authorization code for tokens
   * POST /api/v1/auth/token-exchange
   */
  async exchangeToken(req: Request, res: Response): Promise<void> {
    try {
      logger.info('Token exchange request received', {
        body: {
          code: req.body?.code ? `${req.body.code.substring(0, 10)}...` : 'MISSING',
          redirectUri: req.body?.redirectUri,
        },
        headers: req.headers,
      });
      
      const { code, redirectUri } = validateTokenExchange(req.body);
      logger.info('Token exchange validation passed', { redirectUri });
      
      const result = await this.authService.exchangeCodeForTokens(code, redirectUri);
      
      // Set cookies with httpOnly flag for security
      const isProduction = process.env.NODE_ENV === 'production';
      const cookieOptions = {
        httpOnly: true,
        secure: isProduction,
        sameSite: 'lax' as const,
        maxAge: 24 * 60 * 60 * 1000, // 24 hours for access token
      };

      res.cookie('accessToken', result.accessToken, cookieOptions);
      
      const refreshCookieOptions = {
        ...cookieOptions,
        maxAge: 7 * 24 * 60 * 60 * 1000, // 7 days for refresh token
      };
      
      res.cookie('refreshToken', result.refreshToken, refreshCookieOptions);

      // Ensure Content-Type is set to JSON
      res.setHeader('Content-Type', 'application/json');
      
      logger.info('Sending token exchange response', {
        hasUser: !!result.user,
        hasAccessToken: !!result.accessToken,
        hasRefreshToken: !!result.refreshToken,
      });
      
      ResponseHandler.success(res, {
        user: result.user,
        accessToken: result.accessToken,
        refreshToken: result.refreshToken,
        idToken: result.oktaIdToken // Include id_token for frontend logout
      }, 'Token exchange successful');
    } catch (error) {
      logger.error('Token exchange failed:', error);
      const errorMessage = error instanceof Error ? error.message : 'Unknown error';
      ResponseHandler.error(res, 'Token exchange failed', 400, errorMessage);
    }
  }
}