const { prisma } = require('../utils/db');
const { hashPassword, comparePassword, generateToken } = require('../utils/auth');

// Register new user
async function register(req, res, next) {
  try {
    const { username, email, password } = req.body;

    // Check if user already exists
    const existingUser = await prisma.user.findFirst({
      where: {
        OR: [
          { email },
          { username },
        ],
      },
    });

    if (existingUser) {
      if (existingUser.email === email) {
        return res.status(400).json({
          success: false,
          error: 'Email already registered',
        });
      }
      return res.status(400).json({
        success: false,
        error: 'Username already taken',
      });
    }

    // Hash password
    const passwordHash = await hashPassword(password);

    // Create user
    const user = await prisma.user.create({
      data: {
        username,
        email,
        passwordHash,
        avatar: `https://ui-avatars.com/api/?name=${encodeURIComponent(username)}&background=6366f1&color=fff`,
      },
      select: {
        id: true,
        username: true,
        email: true,
        avatar: true,
        createdAt: true,
      },
    });

    // Generate token
    const token = generateToken({ userId: user.id });

    res.status(201).json({
      success: true,
      message: 'User registered successfully',
      data: {
        user,
        token,
      },
    });
  } catch (error) {
    next(error);
  }
}

// Login user
async function login(req, res, next) {
  try {
    const { email, password } = req.body;

    // Find user by email
    const user = await prisma.user.findUnique({
      where: { email },
    });

    if (!user) {
      return res.status(401).json({
        success: false,
        error: 'Invalid credentials',
      });
    }

    // Compare password
    const isPasswordValid = await comparePassword(password, user.passwordHash);

    if (!isPasswordValid) {
      return res.status(401).json({
        success: false,
        error: 'Invalid credentials',
      });
    }

    // Generate token
    const token = generateToken({ userId: user.id });

    // Return user without password
    const { passwordHash, ...userWithoutPassword } = user;

    res.json({
      success: true,
      message: 'Login successful',
      data: {
        user: userWithoutPassword,
        token,
      },
    });
  } catch (error) {
    next(error);
  }
}

module.exports = {
  register,
  login,
};