import { NextResponse } from 'next/server';
import pool from '@/lib/db';
import bcrypt from 'bcryptjs';
import { SignJWT } from 'jose';
import { RowDataPacket } from 'mysql2';

interface User extends RowDataPacket {
  id_user: number;
  nim: string;
  username: string;
  password: string;
  role: string;
}

export async function POST(request: Request) {
  let connection;
  try {
    console.log('Login request received');
    
    // Test database connection first
    try {
      connection = await pool.getConnection();
      console.log('Database connection successful');
    } catch (dbError) {
      console.error('Database connection error:', dbError);
      return NextResponse.json(
        { error: 'Tidak dapat terhubung ke database' },
        { status: 500 }
      );
    }

    const body = await request.json();
    console.log('Request body:', body);
    
    const { nim, password } = body;
    console.log('Extracted credentials:', { nim, password: '***' });

    // Validate input
    if (!nim || !password) {
      console.log('Missing credentials:', { nim: !!nim, password: !!password });
      return NextResponse.json(
        { error: 'NIM dan password harus diisi' },
        { status: 400 }
      );
    }

    // Get user by NIM
    console.log('Querying user with NIM:', nim);
    let users: User[];
    try {
      const [rows] = await connection.execute<User[]>(
        'SELECT * FROM user WHERE nim = ?',
        [nim]
      );
      users = rows;
      console.log('Query result:', users.length > 0 ? 'User found' : 'User not found');
    } catch (queryError) {
      console.error('Database query error:', queryError);
      return NextResponse.json(
        { error: 'Terjadi kesalahan saat memeriksa data pengguna' },
        { status: 500 }
      );
    }

    if (users.length === 0) {
      console.log('No user found with NIM:', nim);
      connection.release();
      return NextResponse.json(
        { error: 'NIM atau password salah' },
        { status: 401 }
      );
    }

    const user = users[0];
    console.log('User found:', { 
      id: user.id_user, 
      nim: user.nim, 
      username: user.username, 
      role: user.role 
    });

    // Verify password
    console.log('Verifying password...');
    let isPasswordValid;
    try {
      isPasswordValid = await bcrypt.compare(password, user.password);
      console.log('Password verification result:', isPasswordValid ? 'Valid' : 'Invalid');
    } catch (bcryptError) {
      console.error('Password verification error:', bcryptError);
      return NextResponse.json(
        { error: 'Terjadi kesalahan saat memverifikasi password' },
        { status: 500 }
      );
    }

    if (!isPasswordValid) {
      console.log('Invalid password for user:', nim);
      connection.release();
      return NextResponse.json(
        { error: 'NIM atau password salah' },
        { status: 401 }
      );
    }

    // Create JWT token
    console.log('Creating JWT token...');
    let token;
    try {
      token = await new SignJWT({
        id: user.id_user,
        nim: user.nim,
        role: user.role
      })
        .setProtectedHeader({ alg: 'HS256' })
        .setExpirationTime('24h')
        .sign(new TextEncoder().encode(process.env.JWT_SECRET || 'your-secret-key'));
      console.log('JWT token created');
    } catch (jwtError) {
      console.error('JWT creation error:', jwtError);
      return NextResponse.json(
        { error: 'Terjadi kesalahan saat membuat token' },
        { status: 500 }
      );
    }

    // Set cookie
    console.log('Setting response...');
    const response = NextResponse.json({
      user: {
        id: user.id_user,
        nim: user.nim,
        username: user.username,
        role: user.role
      }
    });

    response.cookies.set('token', token, {
      httpOnly: true,
      secure: false,
      sameSite: 'lax',
      maxAge: 60 * 60 * 24 // 24 hours
    });
    console.log('Cookie set');

    connection.release();
    console.log('Login process completed successfully');
    return response;
  } catch (error) {
    if (connection) {
      connection.release();
    }
    
    console.error('Login error details:', error);
    if (error instanceof Error) {
      console.error('Error message:', error.message);
      console.error('Error stack:', error.stack);
    }
    return NextResponse.json(
      { error: 'Terjadi kesalahan saat login' },
      { status: 500 }
    );
  }
}

// Handle OPTIONS request for CORS
export async function OPTIONS() {
  return NextResponse.json({}, {
    headers: {
      'Access-Control-Allow-Origin': '*',
      'Access-Control-Allow-Methods': 'GET, POST, PUT, DELETE, OPTIONS',
      'Access-Control-Allow-Headers': 'Content-Type, Authorization',
    }
  });
}