const User = require('../models/User');
const jwt = require('jsonwebtoken');

const register = async (req, res) => {
    try {
        const { email, password, roles, role, firstName, lastName } = req.body;
        // Use `roles` array if provided, fall back to single `role`
        const selectedRoles = roles && roles.length > 0 ? roles : [role || 'customer'];
        const primaryRole = selectedRoles[0];

        const userExists = await User.findOne({ email });

        if (userExists) {
            // If user exists, try to merge roles (add new roles to existing ones)
            const isMatch = await userExists.comparePassword(password);
            if (isMatch) {
                // Merge new roles with existing ones
                const mergedRoles = [...new Set([...userExists.roles, ...selectedRoles])];
                userExists.roles = mergedRoles;
                userExists.role = mergedRoles[0]; // keep first as primary
                await userExists.save();
                return res.status(200).json({
                    _id: userExists._id,
                    email: userExists.email,
                    role: userExists.role,
                    roles: userExists.roles,
                    firstName: userExists.firstName,
                    lastName: userExists.lastName,
                    token: generateToken(userExists._id),
                });
            }
            return res.status(400).json({ message: 'User already exists with this email.' });
        }

        const user = await User.create({
            email, password,
            role: primaryRole,
            roles: selectedRoles,
            firstName, lastName
        });

        if (user) {
            res.status(201).json({
                _id: user._id,
                email: user.email,
                role: user.role,
                roles: user.roles,
                firstName: user.firstName,
                lastName: user.lastName,
                token: generateToken(user._id)
            });
        }
    } catch (error) {
        res.status(500).json({ message: error.message });
    }
};

const login = async (req, res) => {
    try {
        const { email, password } = req.body;
        console.log(`--- Login Attempt ---`);
        console.log(`Input Email: "${email}"`);

        const user = await User.findOne({ email: email.trim() });

        if (!user) {
            console.log(`User NOT found for email: "${email}"`);
            return res.status(401).json({ message: 'No account found with this email address.' });
        }

        console.log(`User found: ${user.email}`);
        const isMatch = await user.comparePassword(password);
        console.log(`Password match result: ${isMatch}`);

        if (isMatch) {
            res.json({
                _id: user._id,
                email: user.email,
                role: user.role,
                roles: user.roles && user.roles.length > 0 ? user.roles : [user.role],
                firstName: user.firstName,
                lastName: user.lastName,
                profilePicture: user.profilePicture,
                bio: user.bio,
                specialty: user.specialty,
                price: user.price,
                address: user.address,
                experience: user.experience,
                rating: user.rating,
                isVerified: user.isVerified,
                portfolio: user.portfolio,
                token: generateToken(user._id)
            });
        } else {
            console.log(`Password comparison failed for ${email}`);
            res.status(401).json({ message: 'Incorrect password. Please try again.' });
        }

    } catch (error) {
        console.error(`Login error:`, error);
        res.status(500).json({ message: error.message });
    }
};

const generateToken = (id) => {
    return jwt.sign({ id }, process.env.JWT_SECRET || 'fallback_demo_secret_key_123', {
        expiresIn: '30d'
    });
};

module.exports = { register, login };