import express from "express";
import cors from "cors";
import bcrypt from "bcryptjs";
import jwt from "jsonwebtoken";
import pg from "pg";

const { Pool } = pg;
const app = express();

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

const {
  DATABASE_URL,
  JWT_SECRET,
  EVOLUTION_BASE_URL,
  EVOLUTION_API_KEY,
  EVOLUTION_INSTANCE,
} = process.env;

if (!DATABASE_URL || !JWT_SECRET) {
  console.error("❌ ERROR FATAL: Faltan variables de entorno");
  process.exit(1);
}

const pool = new Pool({
  connectionString: DATABASE_URL,
  ssl: false 
});

// ==========================================
// 🧠 AUTO-ACTUALIZACIÓN DB (ESTADOS Y LOGS)
// ==========================================
async function autoUpdateDB() {
  const client = await pool.connect();
  try {
    console.log("🔄 Revisando estructura de base de datos...");

    // 1. Tablas Base
    await client.query(`
      CREATE TABLE IF NOT EXISTS users (
        id SERIAL PRIMARY KEY,
        full_name TEXT NOT NULL,
        phone TEXT NOT NULL, 
        email TEXT NOT NULL,
        dni TEXT,
        address TEXT,
        password_hash TEXT NOT NULL,
        is_verified BOOLEAN DEFAULT FALSE,
        owner_id INT,
        role TEXT DEFAULT 'operario',
        created_at TIMESTAMP DEFAULT NOW()
      );
      
      CREATE TABLE IF NOT EXISTS login_codes (
        id SERIAL PRIMARY KEY,
        user_id INT REFERENCES users(id) ON DELETE CASCADE,
        phone TEXT NOT NULL,
        code_hash TEXT NOT NULL,
        purpose TEXT DEFAULT 'register_verify',
        consumed_at TIMESTAMP,
        expires_at TIMESTAMP NOT NULL,
        created_at TIMESTAMP DEFAULT NOW()
      );

      CREATE TABLE IF NOT EXISTS guilds (
        id SERIAL PRIMARY KEY,
        owner_id INT REFERENCES users(id) ON DELETE CASCADE,
        name TEXT NOT NULL, 
        created_at TIMESTAMP DEFAULT NOW()
      );

      CREATE TABLE IF NOT EXISTS user_guilds (
        user_id INT REFERENCES users(id) ON DELETE CASCADE,
        guild_id INT REFERENCES guilds(id) ON DELETE CASCADE,
        PRIMARY KEY (user_id, guild_id)
      );

      CREATE TABLE IF NOT EXISTS companies (
        id SERIAL PRIMARY KEY,
        owner_id INT REFERENCES users(id) ON DELETE CASCADE,
        name TEXT NOT NULL,
        cif TEXT,
        email TEXT,
        phone TEXT,
        address TEXT,
        created_at TIMESTAMP DEFAULT NOW()
      );

      CREATE TABLE IF NOT EXISTS clients (
        id SERIAL PRIMARY KEY,
        owner_id INT REFERENCES users(id) ON DELETE CASCADE,
        full_name TEXT NOT NULL,
        phone TEXT NOT NULL,
        email TEXT,
        addresses JSONB DEFAULT '[]',
        notes TEXT,
        created_at TIMESTAMP DEFAULT NOW()
      );
    `);

    // 2. NUEVO: TABLA DE ESTADOS DE SERVICIO
    await client.query(`
      CREATE TABLE IF NOT EXISTS service_statuses (
        id SERIAL PRIMARY KEY,
        owner_id INT REFERENCES users(id) ON DELETE CASCADE,
        name TEXT NOT NULL, -- Ej: Pendiente, En Proceso, Completado
        color TEXT DEFAULT 'gray', -- gray, blue, green, red, yellow
        is_default BOOLEAN DEFAULT FALSE, -- Estado inicial al crear servicio
        is_final BOOLEAN DEFAULT FALSE, -- Si es estado final (cierra el servicio)
        created_at TIMESTAMP DEFAULT NOW()
      );
    `);

    // 3. TABLA SERVICIOS (Con FK a status)
    await client.query(`
      CREATE TABLE IF NOT EXISTS services (
        id SERIAL PRIMARY KEY,
        owner_id INT REFERENCES users(id) ON DELETE CASCADE,
        client_id INT REFERENCES clients(id) ON DELETE SET NULL,
        status_id INT REFERENCES service_statuses(id) ON DELETE SET NULL, -- NUEVO: ID del estado
        title TEXT,
        description TEXT,
        contact_phone TEXT NOT NULL,
        contact_name TEXT NOT NULL,
        address TEXT NOT NULL,
        email TEXT,
        scheduled_date DATE DEFAULT CURRENT_DATE,
        scheduled_time TIME DEFAULT CURRENT_TIME,
        duration_minutes INT DEFAULT 30,
        is_urgent BOOLEAN DEFAULT FALSE,
        is_company BOOLEAN DEFAULT FALSE,
        company_id INT REFERENCES companies(id) ON DELETE SET NULL,
        company_ref TEXT,
        internal_notes TEXT,
        client_notes TEXT,
        closed_at TIMESTAMP,
        created_at TIMESTAMP DEFAULT NOW()
      );
    `);

    // 4. NUEVO: TABLA LOGS DE ESTADOS (TRAZABILIDAD)
    await client.query(`
      CREATE TABLE IF NOT EXISTS service_logs (
        id SERIAL PRIMARY KEY,
        service_id INT REFERENCES services(id) ON DELETE CASCADE,
        user_id INT REFERENCES users(id) ON DELETE SET NULL, -- Quién hizo el cambio
        old_status_id INT REFERENCES service_statuses(id),
        new_status_id INT REFERENCES service_statuses(id),
        comment TEXT, -- Comentario del cambio (ej: "Cliente no estaba")
        created_at TIMESTAMP DEFAULT NOW()
      );
    `);

    // 5. PARCHES Y DATOS POR DEFECTO
    try { await client.query(`ALTER TABLE users DROP CONSTRAINT IF EXISTS users_phone_key`); } catch (e) {}
    try { await client.query(`ALTER TABLE users DROP CONSTRAINT IF EXISTS users_email_key`); } catch (e) {}

    await client.query(`
      DO $$ BEGIN 
        IF NOT EXISTS (SELECT 1 FROM information_schema.columns WHERE table_name='services' AND column_name='status_id') THEN 
            ALTER TABLE services ADD COLUMN status_id INT REFERENCES service_statuses(id) ON DELETE SET NULL; 
        END IF;
      END $$;
    `);

    // Crear estados por defecto para cada cuenta nueva (Esto se haría al registrarse, pero lo simulamos aquí)
    // Nota: Como es multitenant, cada usuario crea sus estados. Para simplificar, asumiremos que el frontend pide crear los defaults si no existen.

    console.log("✅ DB Sincronizada (Estados y Logs listos).");
  } catch (e) { console.error("❌ Error DB:", e); } finally { client.release(); }
}

// HELPERS
function normalizePhone(phone) {
  let p = String(phone || "").trim().replace(/\s+/g, "").replace(/-/g, "");
  if (!p) return "";
  if (!p.startsWith("+") && /^[6789]\d{8}$/.test(p)) return "+34" + p;
  return p;
}
function signToken(user) {
  const accountId = user.owner_id || user.id;
  return jwt.sign({ sub: user.id, email: user.email, phone: user.phone, role: user.role || 'operario', accountId }, JWT_SECRET, { expiresIn: "30d" });
}
function authMiddleware(req, res, next) {
  const h = req.headers.authorization || "";
  const token = h.startsWith("Bearer ") ? h.slice(7) : "";
  if (!token) return res.status(401).json({ ok: false, error: "No token" });
  try { req.user = jwt.verify(token, JWT_SECRET); next(); } 
  catch { return res.status(401).json({ ok: false, error: "Token inválido" }); }
}

// =========================
// RUTAS PRINCIPALES (AUTH, ETC.)
// =========================
app.post("/auth/login", async (req, res) => { /* ... (Copia tu login actual) ... */ });
// (Mantén tus rutas de auth, usuarios y gremios iguales)

// =========================
// API ESTADOS (STATUSES)
// =========================
app.get("/statuses", authMiddleware, async (req, res) => {
    try {
        let q = await pool.query("SELECT * FROM service_statuses WHERE owner_id=$1 ORDER BY id ASC", [req.user.accountId]);
        
        // Si no tiene estados, creamos los por defecto
        if (q.rowCount === 0) {
            const defaults = [
                { name: 'Pendiente', color: 'gray', def: true, fin: false },
                { name: 'En Proceso', color: 'blue', def: false, fin: false },
                { name: 'Completado', color: 'green', def: false, fin: true },
                { name: 'Cancelado', color: 'red', def: false, fin: true }
            ];
            for (const s of defaults) {
                await pool.query(
                    "INSERT INTO service_statuses (owner_id, name, color, is_default, is_final) VALUES ($1, $2, $3, $4, $5)",
                    [req.user.accountId, s.name, s.color, s.def, s.fin]
                );
            }
            q = await pool.query("SELECT * FROM service_statuses WHERE owner_id=$1 ORDER BY id ASC", [req.user.accountId]);
        }
        res.json({ ok: true, statuses: q.rows });
    } catch (e) { res.status(500).json({ ok: false, error: e.message }); }
});

// =========================
// API SERVICIOS (ACTUALIZADA)
// =========================

// GET SERVICIOS (Con Estado actual)
app.get("/services", authMiddleware, async (req, res) => {
    try {
        const q = await pool.query(`
            SELECT s.*, c.name as company_name, st.name as status_name, st.color as status_color
            FROM services s 
            LEFT JOIN companies c ON s.company_id = c.id
            LEFT JOIN service_statuses st ON s.status_id = st.id
            WHERE s.owner_id=$1 
            ORDER BY s.created_at DESC`, 
            [req.user.accountId]
        );
        res.json({ ok: true, services: q.rows });
    } catch (e) { res.status(500).json({ ok: false, error: "Error servicios" }); }
});

// GET HISTORIAL DE UN SERVICIO
app.get("/services/:id/logs", authMiddleware, async (req, res) => {
    try {
        const q = await pool.query(`
            SELECT l.*, u.full_name as user_name, s1.name as old_status, s2.name as new_status, s2.color as new_color
            FROM service_logs l
            LEFT JOIN users u ON l.user_id = u.id
            LEFT JOIN service_statuses s1 ON l.old_status_id = s1.id
            LEFT JOIN service_statuses s2 ON l.new_status_id = s2.id
            WHERE l.service_id = $1
            ORDER BY l.created_at DESC
        `, [req.params.id]);
        res.json({ ok: true, logs: q.rows });
    } catch (e) { res.status(500).json({ ok: false }); }
});

// CAMBIAR ESTADO SERVICIO
app.put("/services/:id/status", authMiddleware, async (req, res) => {
    const client = await pool.connect();
    try {
        const { status_id, comment } = req.body;
        const serviceId = req.params.id;

        await client.query('BEGIN');

        // 1. Obtener estado actual
        const current = await client.query("SELECT status_id FROM services WHERE id=$1", [serviceId]);
        const oldStatusId = current.rows[0].status_id;

        // 2. Actualizar servicio
        await client.query("UPDATE services SET status_id=$1 WHERE id=$2", [status_id, serviceId]);

        // 3. Insertar Log
        await client.query(`
            INSERT INTO service_logs (service_id, user_id, old_status_id, new_status_id, comment)
            VALUES ($1, $2, $3, $4, $5)
        `, [serviceId, req.user.sub, oldStatusId, status_id, comment || "Cambio de estado manual"]);

        await client.query('COMMIT');
        res.json({ ok: true });
    } catch (e) {
        await client.query('ROLLBACK');
        res.status(500).json({ ok: false });
    } finally { client.release(); }
});

// CREAR SERVICIO (Asigna estado por defecto)
app.post("/services", authMiddleware, async (req, res) => {
    const client = await pool.connect();
    try {
        const { phone, name, address, email, description, scheduled_date, scheduled_time, duration, is_urgent, is_company, company_id, company_ref, internal_notes, client_notes } = req.body;
        const p = normalizePhone(phone);
        
        await client.query('BEGIN');

        // Buscar estado por defecto
        const defStatus = await client.query("SELECT id FROM service_statuses WHERE owner_id=$1 AND is_default=TRUE LIMIT 1", [req.user.accountId]);
        const statusId = defStatus.rows[0]?.id;

        // ... (Lógica de Cliente igual que antes) ...
        // Simplificado para brevedad, aquí iría la búsqueda/creación de cliente que ya tienes.
        // Asumimos clientId ya obtenido.
        let clientId; 
        // [TU CÓDIGO DE CLIENTE AQUÍ] - Si quieres que lo repita dímelo, pero es igual al anterior.
        
        // Crear Servicio
        const insert = await client.query(`
            INSERT INTO services (
                owner_id, client_id, status_id, contact_phone, contact_name, address, email,
                description, scheduled_date, scheduled_time, duration_minutes, is_urgent,
                is_company, company_id, company_ref, internal_notes, client_notes, title
            ) VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18)
            RETURNING id
        `, [
            req.user.accountId, 1, statusId, p, name, address, email, // Pongo client_id=1 hardcodeado para ejemplo, usa tu lógica real
            description, scheduled_date || 'NOW()', scheduled_time || 'NOW()', duration || 30, is_urgent || false,
            is_company || false, company_id || null, company_ref, internal_notes, client_notes, name + " - Servicio"
        ]);

        // Log inicial
        await client.query(`
            INSERT INTO service_logs (service_id, user_id, new_status_id, comment)
            VALUES ($1, $2, $3, 'Servicio creado')
        `, [insert.rows[0].id, req.user.sub, statusId]);

        await client.query('COMMIT');
        res.json({ ok: true });
    } catch (e) { await client.query('ROLLBACK'); res.status(500).json({ ok: false }); } finally { client.release(); }
});

const port = process.env.PORT || 3000;
autoUpdateDB().then(() => {
  app.listen(port, "0.0.0.0", () => console.log(`🚀 Server OK en puerto ${port}`));
});