const express = require('express');
const cors = require('cors');
const path = require('path');
const bcrypt = require('bcryptjs');
const jwt = require('jsonwebtoken');
const crypto = require('crypto');
const nodemailer = require('nodemailer');
const pool = require('./db');

const app = express();
const PORT = process.env.PORT || 3001;
const JWT_SECRET = process.env.JWT_SECRET || 'fasto_super_secret_key';

// Configuração do Transportador de E-mail
const transporter = nodemailer.createTransport({
  host: process.env.SMTP_HOST || 'mail.blyzer.com.br',
  port: parseInt(process.env.SMTP_PORT) || 587,
  secure: false, // false para 587 (STARTTLS)
  auth: {
    user: process.env.SMTP_USER || 'nao-responda@blyzer.com.br',
    pass: process.env.SMTP_PASS || '',
  },
  tls: {
    ciphers: 'SSLv3',
    rejectUnauthorized: false
  },
  debug: true, // Habilitar debug
  logger: true // Logar no console
});

app.use(cors());
app.use(express.json());

// Logger de Requisições
app.use((req, res, next) => {
  console.log(`[${new Date().toISOString()}] ${req.method} ${req.url}`);
  next();
});

// --- API Router ---
const apiRouter = express.Router();

// --- Auth Routes ---

// Register
apiRouter.post('/auth/register', async (req, res) => {
  const { name, email, password, organizationName } = req.body;
  try {
    const [existing] = await pool.query('SELECT id FROM users WHERE email = ?', [email]);
    if (existing.length > 0) return res.status(400).json({ error: 'E-mail já cadastrado.' });

    const passwordHash = await bcrypt.hash(password, 10);
    const verificationCode = Math.floor(100000 + Math.random() * 900000).toString();
    const expiresAt = new Date(Date.now() + 15 * 60 * 1000);

    await pool.query(
      'INSERT INTO pending_registrations (email, password_hash, full_name, organization_name, verification_code, expires_at) VALUES (?, ?, ?, ?, ?, ?)',
      [email, passwordHash, name, organizationName, verificationCode, expiresAt]
    );

    const mailOptions = {
      from: `"Fasto" <${process.env.MAIL_FROM || 'nao-responda@blyzer.com.br'}>`,
      to: email,
      subject: 'Seu código de verificação Fasto',
      text: `Olá ${name}, seu código de verificação é: ${verificationCode}`,
      html: `
        <div style="font-family: sans-serif; max-width: 600px; margin: 0 auto; padding: 20px; border: 1px solid #e2e8f0; border-radius: 12px;">
          <h2 style="color: #0f172a;">Bem-vindo ao Fasto!</h2>
          <p style="color: #475569;">Seu código: <strong>${verificationCode}</strong></p>
        </div>`
    };
    await transporter.sendMail(mailOptions);
    res.json({ message: 'Código enviado.' });
  } catch (error) {
    console.error('Register error:', error);
    res.status(500).json({ error: error.message });
  }
});

// Verify
apiRouter.post('/auth/verify', async (req, res) => {
  const { email, code } = req.body;
  const connection = await pool.getConnection();
  try {
    await connection.beginTransaction();
    const [pending] = await connection.query(
      'SELECT * FROM pending_registrations WHERE email = ? AND verification_code = ? AND expires_at > NOW() ORDER BY created_at DESC LIMIT 1',
      [email, code]
    );
    if (pending.length === 0) return res.status(400).json({ error: 'Código inválido.' });

    const data = pending[0];
    const tenantId = `tenant_${crypto.randomUUID().split('-')[0]}`;
    const userId = `u_${crypto.randomUUID().split('-')[0]}`;

    await connection.query('INSERT INTO tenants (id, name, slug, admin_email) VALUES (?, ?, ?, ?)', 
      [tenantId, data.organization_name, data.organization_name.toLowerCase().replace(/ /g, '-'), email]);
    await connection.query('INSERT INTO users (id, tenant_id, name, email, password_hash, role) VALUES (?, ?, ?, ?, ?, ?)',
      [userId, tenantId, data.full_name, email, data.password_hash, 'owner']);
    await connection.query('DELETE FROM pending_registrations WHERE email = ?', [email]);

    await connection.commit();
    res.json({ message: 'Sucesso.' });
  } catch (error) {
    await connection.rollback();
    res.status(500).json({ error: error.message });
  } finally {
    connection.release();
  }
});

// Login
apiRouter.post('/auth/login', async (req, res) => {
  const { email, password } = req.body;
  try {
    const [users] = await pool.query('SELECT * FROM users WHERE email = ?', [email]);
    if (users.length === 0) return res.status(401).json({ error: 'Credenciais inválidas.' });
    
    const user = users[0];

    // Verificar se o usuário está ativo
    if (user.status !== 'active') {
      return res.status(403).json({ error: 'Sua conta está inativa. Contate o administrador.' });
    }

    const valid = await bcrypt.compare(password, user.password_hash);
    if (!valid) return res.status(401).json({ error: 'Credenciais inválidas.' });

    const token = jwt.sign({ id: user.id, tenant_id: user.tenant_id, role: user.role }, JWT_SECRET, { expiresIn: '24h' });
    res.json({ token, user: { id: user.id, name: user.name, email: user.email, role: user.role, tenant_id: user.tenant_id } });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Forgot Password
apiRouter.post('/auth/forgot-password', async (req, res) => {
  const { email } = req.body;
  try {
    const [users] = await pool.query('SELECT name FROM users WHERE email = ?', [email]);
    if (users.length > 0) {
      const token = crypto.randomBytes(32).toString('hex');
      await pool.query('INSERT INTO password_resets (email, token, expires_at) VALUES (?, ?, DATE_ADD(NOW(), INTERVAL 1 HOUR))', [email, token]);
      const link = `${process.env.APP_URL || 'http://localhost:3001'}/#/reset-password?token=${token}`;
      
      const mailOptions = {
        from: `"Fasto" <${process.env.MAIL_FROM || 'nao-responda@blyzer.com.br'}>`,
        to: email,
        subject: 'Recuperação de Senha - Fasto',
        html: `
          <div style="font-family: sans-serif; max-width: 600px; margin: 0 auto; padding: 20px; border: 1px solid #e2e8f0; border-radius: 12px;">
            <h2 style="color: #0f172a;">Olá, ${users[0].name}!</h2>
            <p style="color: #475569;">Você solicitou a recuperação de senha da sua conta no Fasto.</p>
            <p style="color: #475569;">Clique no botão abaixo para criar uma nova senha:</p>
            <div style="text-align: center; margin: 30px 0;">
              <a href="${link}" style="background-color: #0f172a; color: white; padding: 12px 24px; text-decoration: none; border-radius: 8px; font-weight: bold; display: inline-block;">Redefinir Minha Senha</a>
            </div>
            <p style="font-size: 12px; color: #94a3b8;">Este link expira em 1 hora. Se você não solicitou isso, pode ignorar este e-mail.</p>
            <div style="border-top: 1px solid #f1f5f9; margin-top: 20px; padding-top: 20px; text-align: center;">
              <p style="font-size: 12px; color: #94a3b8;">Desenvolvido por <a href="https://blyzer.com.br" style="color: #3b82f6; text-decoration: none;">Blyzer</a></p>
            </div>
          </div>
        `
      };
      await transporter.sendMail(mailOptions);
    }
    res.json({ message: 'Se o e-mail existir, enviamos as instruções.' });
  } catch (error) {
    console.error('Forgot password error:', error);
    res.status(500).json({ error: error.message });
  }
});

// Reset Password
apiRouter.post('/auth/reset-password', async (req, res) => {
  const { token, password } = req.body;
  try {
    const [resets] = await pool.query('SELECT email FROM password_resets WHERE token = ? AND expires_at > NOW()', [token]);
    if (resets.length === 0) return res.status(400).json({ error: 'Token inválido.' });
    const hash = await bcrypt.hash(password, 10);
    await pool.query('UPDATE users SET password_hash = ? WHERE email = ?', [hash, resets[0].email]);
    await pool.query('DELETE FROM password_resets WHERE email = ?', [resets[0].email]);
    res.json({ message: 'Senha resetada.' });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// --- User Routes ---
apiRouter.get('/users', async (req, res) => {
  try {
    const { tenantId } = req.query;
    let q = 'SELECT * FROM users';
    const params = [];
    if (tenantId && tenantId !== 'all') { q += ' WHERE tenant_id = ?'; params.push(tenantId); }
    const [rows] = await pool.query(q, params);
    res.json(rows);
  } catch (error) { res.status(500).json({ error: error.message }); }
});

apiRouter.get('/users/:id', async (req, res) => {
  try {
    const [rows] = await pool.query('SELECT * FROM users WHERE id = ?', [req.params.id]);
    if (rows.length === 0) return res.status(404).json({ error: 'Not found' });
    res.json(rows[0]);
  } catch (error) { res.status(500).json({ error: error.message }); }
});

// Convidar Novo Membro (Admin criando usuário)
apiRouter.post('/users', async (req, res) => {
  const { name, email, role, team_id, tenant_id } = req.body;
  console.log('--- User Creation Request ---');
  console.log('Body:', req.body);
  try {
    // 1. Verificar se e-mail já existe
    const [existing] = await pool.query('SELECT id FROM users WHERE email = ?', [email]);
    if (existing.length > 0) return res.status(400).json({ error: 'E-mail já cadastrado.' });

    const uid = `u_${crypto.randomUUID().split('-')[0]}`;
    const placeholderHash = 'pending_setup'; // Usuário não pode logar com isso

    // 2. Criar Usuário
    await pool.query(
      'INSERT INTO users (id, tenant_id, team_id, name, email, password_hash, role, status) VALUES (?, ?, ?, ?, ?, ?, ?, ?)',
      [uid, tenant_id, team_id || null, name, email, placeholderHash, role || 'agent', 'active']
    );

    // 3. Gerar Token de Setup de Senha (reusando lógica de reset)
    const token = crypto.randomBytes(32).toString('hex');
    await pool.query(
      'INSERT INTO password_resets (email, token, expires_at) VALUES (?, ?, DATE_ADD(NOW(), INTERVAL 24 HOUR))',
      [email, token]
    );

    // 4. Enviar E-mail de Boas-vindas
    const setupLink = `${process.env.APP_URL || 'http://localhost:3001'}/#/reset-password?token=${token}`;
    
    await transporter.sendMail({
      from: `"Fasto" <${process.env.MAIL_FROM || 'nao-responda@blyzer.com.br'}>`,
      to: email,
      subject: 'Bem-vindo ao Fasto - Crie sua senha',
      html: `
        <div style="font-family: sans-serif; max-width: 600px; margin: 0 auto; padding: 20px; border: 1px solid #e2e8f0; border-radius: 12px;">
          <h2 style="color: #0f172a;">Olá, ${name}!</h2>
          <p style="color: #475569;">Você foi convidado para participar da equipe no Fasto.</p>
          <p style="color: #475569;">Clique no botão abaixo para definir sua senha e acessar sua conta:</p>
          <div style="text-align: center; margin: 30px 0;">
            <a href="${setupLink}" style="background-color: #0f172a; color: white; padding: 12px 24px; text-decoration: none; border-radius: 8px; font-weight: bold; display: inline-block;">Definir Minha Senha</a>
          </div>
          <p style="font-size: 12px; color: #94a3b8;">Este link expira em 24 horas. Se você não esperava este convite, ignore este e-mail.</p>
          <div style="border-top: 1px solid #f1f5f9; margin-top: 20px; padding-top: 20px; text-align: center;">
            <p style="font-size: 12px; color: #94a3b8;">Desenvolvido por <a href="https://blyzer.com.br" style="color: #3b82f6; text-decoration: none;">Blyzer</a></p>
          </div>
        </div>
      `
    });

    res.status(201).json({ id: uid, message: 'Convite enviado com sucesso.' });
  } catch (error) {
    console.error('Invite error:', error);
    res.status(500).json({ error: error.message });
  }
});

apiRouter.put('/users/:id', async (req, res) => {
  const { name, bio, role, team_id, status } = req.body;
  try {
    await pool.query(
      'UPDATE users SET name = ?, bio = ?, role = ?, team_id = ?, status = ? WHERE id = ?',
      [name, bio, role, team_id || null, status, req.params.id]
    );
    res.json({ message: 'User updated successfully.' });
  } catch (error) {
    console.error('Update user error:', error);
    res.status(500).json({ error: error.message });
  }
});

apiRouter.delete('/users/:id', async (req, res) => {
  try {
    await pool.query('DELETE FROM users WHERE id = ?', [req.params.id]);
    res.json({ message: 'User deleted successfully.' });
  } catch (error) {
    console.error('Delete user error:', error);
    res.status(500).json({ error: error.message });
  }
});


// --- Attendance Routes ---
apiRouter.get('/attendances', async (req, res) => {
  try {
    const { tenantId, userId, teamId, startDate, endDate } = req.query;
    let q = 'SELECT a.*, u.team_id FROM attendances a JOIN users u ON a.user_id = u.id WHERE a.tenant_id = ?';
    const params = [tenantId];
    if (startDate && endDate) { q += ' AND a.created_at BETWEEN ? AND ?'; params.push(new Date(startDate), new Date(endDate)); }
    if (userId && userId !== 'all') { q += ' AND a.user_id = ?'; params.push(userId); }
    if (teamId && teamId !== 'all') { q += ' AND u.team_id = ?'; params.push(teamId); }
    q += ' ORDER BY a.created_at DESC';
    const [rows] = await pool.query(q, params);
    const processed = rows.map(r => ({
      ...r,
      attention_points: typeof r.attention_points === 'string' ? JSON.parse(r.attention_points) : r.attention_points,
      improvement_points: typeof r.improvement_points === 'string' ? JSON.parse(r.improvement_points) : r.improvement_points,
      converted: Boolean(r.converted)
    }));
    res.json(processed);
  } catch (error) { res.status(500).json({ error: error.message }); }
});

apiRouter.get('/attendances/:id', async (req, res) => {
  try {
    const [rows] = await pool.query('SELECT * FROM attendances WHERE id = ?', [req.params.id]);
    if (rows.length === 0) return res.status(404).json({ error: 'Not found' });
    const r = rows[0];
    res.json({
      ...r,
      attention_points: typeof r.attention_points === 'string' ? JSON.parse(r.attention_points) : r.attention_points,
      improvement_points: typeof r.improvement_points === 'string' ? JSON.parse(r.improvement_points) : r.improvement_points,
      converted: Boolean(r.converted)
    });
  } catch (error) { res.status(500).json({ error: error.message }); }
});

// --- Tenant Routes ---
apiRouter.get('/tenants', async (req, res) => {
  try {
    const q = 'SELECT t.*, (SELECT COUNT(*) FROM users u WHERE u.tenant_id = t.id) as user_count, (SELECT COUNT(*) FROM attendances a WHERE a.tenant_id = t.id) as attendance_count FROM tenants t';
    const [rows] = await pool.query(q);
    res.json(rows);
  } catch (error) { res.status(500).json({ error: error.message }); }
});

// --- Team Routes ---
apiRouter.get('/teams', async (req, res) => {
  try {
    const { tenantId } = req.query;
    const [rows] = await pool.query('SELECT * FROM teams WHERE tenant_id = ?', [tenantId]);
    res.json(rows);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

apiRouter.post('/teams', async (req, res) => {
  const { name, description, tenantId } = req.body;
  try {
    const tid = `team_${crypto.randomUUID().split('-')[0]}`;
    await pool.query(
      'INSERT INTO teams (id, tenant_id, name, description) VALUES (?, ?, ?, ?)',
      [tid, tenantId, name, description || null]
    );
    res.status(201).json({ id: tid, message: 'Time criado com sucesso.' });
  } catch (error) {
    console.error('Create team error:', error);
    res.status(500).json({ error: error.message });
  }
});

apiRouter.put('/teams/:id', async (req, res) => {
  const { name, description } = req.body;
  try {
    await pool.query(
      'UPDATE teams SET name = ?, description = ? WHERE id = ?',
      [name, description || null, req.params.id]
    );
    res.json({ message: 'Team updated successfully.' });
  } catch (error) {
    console.error('Update team error:', error);
    res.status(500).json({ error: error.message });
  }
});



apiRouter.post('/tenants', async (req, res) => {
  const { name, slug, admin_email, status } = req.body;
  const connection = await pool.getConnection();
  try {
    await connection.beginTransaction();
    const tid = `tenant_${crypto.randomUUID().split('-')[0]}`;
    await connection.query('INSERT INTO tenants (id, name, slug, admin_email, status) VALUES (?, ?, ?, ?, ?)', [tid, name, slug, admin_email, status || 'active']);
    const uid = `u_${crypto.randomUUID().split('-')[0]}`;
    await connection.query('INSERT INTO users (id, tenant_id, name, email, role) VALUES (?, ?, ?, ?, ?)', [uid, tid, 'Admin', admin_email, 'admin']);
    await connection.commit();
    res.status(201).json({ id: tid });
  } catch (error) { await connection.rollback(); res.status(500).json({ error: error.message }); } finally { connection.release(); }
});

// Mount the API Router
app.use('/api', apiRouter);

// Serve static files
if (process.env.NODE_ENV === 'production') {
  app.use(express.static(path.join(__dirname, '../dist')));
  app.get('*', (req, res) => {
    // Avoid hijacking API requests
    if (req.url.startsWith('/api')) return res.status(404).json({ error: 'API route not found' });
    res.sendFile(path.join(__dirname, '../dist/index.html'));
  });
}

app.listen(PORT, () => {
  console.log(`🚀 Servidor Backend rodando em http://localhost:${PORT}`);
});