require('dotenv').config();
const express = require('express');
const mysql = require('mysql2/promise');
const bcrypt = require('bcryptjs');
const jwt = require('jsonwebtoken');
const cookieParser = require('cookie-parser');
const multer = require('multer');
const sharp = require('sharp');
const path = require('path');
const fs = require('fs');

const app = express();
const PORT = process.env.PORT || 3000;

// ============================================================
// MIDDLEWARE
// ============================================================
app.use(express.urlencoded({ extended: true }));
app.use(express.json());
app.use(cookieParser());
app.use(express.static('public'));
app.use('/uploads', express.static(path.join(__dirname, 'public/uploads')));

app.set('view engine', 'ejs');
app.set('views', path.join(__dirname, 'views'));

// ============================================================
// CREAR CARPETA UPLOADS
// ============================================================
const uploadDir = path.join(__dirname, 'public/uploads');
if (!fs.existsSync(uploadDir)) {
    fs.mkdirSync(uploadDir, { recursive: true });
}

// ============================================================
// CONEXIÓN A LA BASE DE DATOS
// ============================================================
const pool = mysql.createPool({
    host: process.env.DB_HOST || '127.0.0.1',
    user: process.env.DB_USER || 'u708484156_cms',
    password: process.env.DB_PASSWORD || 'CMS2026!a',
    database: process.env.DB_NAME || 'u708484156_cms',
    waitForConnections: true,
    connectionLimit: 10,
    queueLimit: 0
});

// ============================================================
// CONFIGURACIÓN DE MULTER PARA SUBIDA DE IMÁGENES
// ============================================================
const storage = multer.memoryStorage();
const upload = multer({
    storage: storage,
    limits: { fileSize: 5 * 1024 * 1024 },
    fileFilter: (req, file, cb) => {
        if (file.mimetype.startsWith('image/')) {
            cb(null, true);
        } else {
            cb(new Error('Solo se permiten imágenes'));
        }
    }
});

// ============================================================
// FUNCIÓN PARA GUARDAR IMAGEN CON SHARP
// ============================================================
async function saveImage(file, prefix) {
    const uniqueName = `${prefix}_${Date.now()}_${Math.random().toString(36).substring(7)}.webp`;
    const filePath = path.join(uploadDir, uniqueName);
    await sharp(file.buffer).webp({ quality: 80 }).toFile(filePath);
    return `/uploads/${uniqueName}`;
}

// ============================================================
// RUTA DE PRUEBA
// ============================================================
app.get('/api/test', async (req, res) => {
    try {
        const [rows] = await pool.execute('SELECT 1 as connected');
        res.json({
            success: true,
            message: '✅ Conexión exitosa a la base de datos',
            data: rows
        });
    } catch (error) {
        res.status(500).json({
            success: false,
            message: '❌ Error de conexión: ' + error.message
        });
    }
});

// ============================================================
// RUTAS DEL SITIO PÚBLICO
// ============================================================
app.get('/', async (req, res) => {
    try {
        const [config] = await pool.execute('SELECT * FROM header_config LIMIT 1');
        const [links] = await pool.execute(
            'SELECT * FROM header_links WHERE is_active = TRUE ORDER BY display_order ASC'
        );

        const header = {
            config: config[0] || {
                site_name: 'Mi Sitio',
                site_description: 'Bienvenido a mi sitio web',
                header_bg_color: '#FFFFFF',
                header_text_color: '#1A1A1A',
                header_link_color: '#333333',
                header_link_hover_color: '#000000',
                logo_text: 'Mi Logo',
                logo_image: null
            },
            links: links || []
        };

        res.render('site/index', {
            title: 'Inicio',
            header: header
        });
    } catch (error) {
        console.error('Error en ruta /:', error);
        const header = {
            config: {
                site_name: 'Mi Sitio',
                site_description: 'Bienvenido a mi sitio web',
                header_bg_color: '#FFFFFF',
                header_text_color: '#1A1A1A',
                header_link_color: '#333333',
                header_link_hover_color: '#000000',
                logo_text: 'Mi Logo',
                logo_image: null
            },
            links: [
                { label: 'Inicio', url: '/' },
                { label: 'Acerca de', url: '/acerca' },
                { label: 'Contacto', url: '/contacto' }
            ]
        };
        res.render('site/index', {
            title: 'Inicio',
            header: header
        });
    }
});

// ============================================================
// RUTAS DEL ADMINISTRADOR
// ============================================================

// Login
app.get('/admin', (req, res) => {
    res.render('admin/login', { error: null });
});

// Procesar login
app.post('/admin/login', async (req, res) => {
    try {
        const { email, password } = req.body;
        const [rows] = await pool.execute('SELECT * FROM users WHERE email = ?', [email]);

        if (rows.length === 0) {
            return res.render('admin/login', { error: 'Email o contraseña incorrectos' });
        }

        const validPassword = await bcrypt.compare(password, rows[0].password);
        if (!validPassword) {
            return res.render('admin/login', { error: 'Email o contraseña incorrectos' });
        }

        const token = jwt.sign(
            { id: rows[0].id, email: rows[0].email, name: rows[0].name },
            process.env.JWT_SECRET || 'mi-secreto',
            { expiresIn: '24h' }
        );

        res.cookie('admin_token', token, { httpOnly: true, maxAge: 24 * 60 * 60 * 1000 });
        res.redirect('/admin/dashboard');
    } catch (error) {
        res.render('admin/login', { error: 'Error al iniciar sesión' });
    }
});

// Dashboard
app.get('/admin/dashboard', async (req, res) => {
    try {
        const token = req.cookies.admin_token;
        if (!token) return res.redirect('/admin');

        const decoded = jwt.verify(token, process.env.JWT_SECRET || 'mi-secreto');

        const [config] = await pool.execute('SELECT * FROM header_config LIMIT 1');
        const [links] = await pool.execute(
            'SELECT * FROM header_links ORDER BY display_order ASC'
        );

        const header = {
            config: config[0] || {},
            links: links || []
        };

        res.render('admin/dashboard', {
            user: decoded,
            header: header
        });
    } catch (error) {
        res.redirect('/admin');
    }
});

// Header
app.get('/admin/header', async (req, res) => {
    try {
        const token = req.cookies.admin_token;
        if (!token) return res.redirect('/admin');

        jwt.verify(token, process.env.JWT_SECRET || 'mi-secreto');

        const [config] = await pool.execute('SELECT * FROM header_config LIMIT 1');
        const [links] = await pool.execute(
            'SELECT * FROM header_links ORDER BY display_order ASC'
        );

        res.render('admin/header', {
            config: config[0] || {},
            links: links || [],
            message: null,
            error: null
        });
    } catch (error) {
        res.redirect('/admin');
    }
});

// Guardar configuración del header
app.post('/admin/header/save', upload.single('logo_image'), async (req, res) => {
    try {
        const token = req.cookies.admin_token;
        if (!token) return res.redirect('/admin');

        jwt.verify(token, process.env.JWT_SECRET || 'mi-secreto');

        const {
            site_name,
            site_description,
            header_bg_color,
            header_text_color,
            header_link_color,
            header_link_hover_color,
            logo_text
        } = req.body;

        let logo_image = null;
        if (req.file) {
            logo_image = await saveImage(req.file, 'logo');
        }

        const [current] = await pool.execute('SELECT * FROM header_config LIMIT 1');

        if (current.length === 0) {
            await pool.execute(
                `INSERT INTO header_config 
                (site_name, site_description, header_bg_color, header_text_color, 
                header_link_color, header_link_hover_color, logo_text, logo_image) 
                VALUES (?, ?, ?, ?, ?, ?, ?, ?)`,
                [
                    site_name || 'Mi Sitio',
                    site_description || '',
                    header_bg_color || '#FFFFFF',
                    header_text_color || '#1A1A1A',
                    header_link_color || '#333333',
                    header_link_hover_color || '#000000',
                    logo_text || 'Mi Logo',
                    logo_image
                ]
            );
        } else {
            let query = `UPDATE header_config SET 
                site_name = ?, site_description = ?, 
                header_bg_color = ?, header_text_color = ?, 
                header_link_color = ?, header_link_hover_color = ?, 
                logo_text = ?`;
            const params = [
                site_name || 'Mi Sitio',
                site_description || '',
                header_bg_color || '#FFFFFF',
                header_text_color || '#1A1A1A',
                header_link_color || '#333333',
                header_link_hover_color || '#000000',
                logo_text || 'Mi Logo'
            ];

            if (logo_image) {
                query += `, logo_image = ?`;
                params.push(logo_image);
            }

            query += ` WHERE id = ?`;
            params.push(current[0].id);

            await pool.execute(query, params);
        }

        const [updatedConfig] = await pool.execute('SELECT * FROM header_config LIMIT 1');
        const [links] = await pool.execute(
            'SELECT * FROM header_links ORDER BY display_order ASC'
        );

        res.render('admin/header', {
            config: updatedConfig[0] || {},
            links: links || [],
            message: '✅ Configuración guardada correctamente',
            error: null
        });
    } catch (error) {
        console.error(error);
        const [config] = await pool.execute('SELECT * FROM header_config LIMIT 1');
        const [links] = await pool.execute(
            'SELECT * FROM header_links ORDER BY display_order ASC'
        );
        res.render('admin/header', {
            config: config[0] || {},
            links: links || [],
            message: null,
            error: '❌ Error al guardar la configuración'
        });
    }
});

// Agregar enlace
app.post('/admin/header/link/add', async (req, res) => {
    try {
        const token = req.cookies.admin_token;
        if (!token) return res.redirect('/admin');

        jwt.verify(token, process.env.JWT_SECRET || 'mi-secreto');

        const { label, url, display_order } = req.body;

        await pool.execute(
            'INSERT INTO header_links (label, url, display_order, is_active) VALUES (?, ?, ?, TRUE)',
            [label, url, display_order || 0]
        );

        res.redirect('/admin/header');
    } catch (error) {
        res.redirect('/admin/header');
    }
});

// Eliminar enlace
app.post('/admin/header/link/delete/:id', async (req, res) => {
    try {
        const token = req.cookies.admin_token;
        if (!token) return res.redirect('/admin');

        jwt.verify(token, process.env.JWT_SECRET || 'mi-secreto');

        await pool.execute('DELETE FROM header_links WHERE id = ?', [req.params.id]);
        res.redirect('/admin/header');
    } catch (error) {
        res.redirect('/admin/header');
    }
});

// Logout
app.get('/admin/logout', (req, res) => {
    res.clearCookie('admin_token');
    res.redirect('/admin');
});

// ============================================================
// INICIAR SERVIDOR
// ============================================================
app.listen(PORT, '0.0.0.0', () => {
    console.log(`✅ Servidor corriendo en puerto ${PORT}`);
    console.log(`📱 Sitio: https://wilmer.tutoflix.com`);
    console.log(`🔐 Admin: https://wilmer.tutoflix.com/admin`);
});