const express = require('express');
const { chromium } = require('playwright');
const admin = require('firebase-admin');
const cors = require('cors');

// --- CONFIGURACIÓN FIREBASE ---
try {
    if (process.env.FIREBASE_PRIVATE_KEY) {
        if (!admin.apps.length) {
            admin.initializeApp({
                credential: admin.credential.cert({
                    projectId: process.env.FIREBASE_PROJECT_ID,
                    clientEmail: process.env.FIREBASE_CLIENT_EMAIL,
                    privateKey: process.env.FIREBASE_PRIVATE_KEY.replace(/\\n/g, '\n'),
                }),
            });
        }
        console.log("✅ Firebase inicializado.");
    }
} catch (e) { console.error("❌ Error Firebase:", e.message); }

const db = admin.apps.length ? admin.firestore() : null;
const APPOINTMENTS_COL = "appointments"; 

const app = express();
app.use(cors({ origin: '*' }));
app.use(express.json({ limit: '10mb' })); // Permitir payloads grandes para guardar

// --- ENDPOINT PRINCIPAL ---
app.post('/api/robot-cobros', async (req, res) => {
    const { action, url, provider, dataToSave } = req.body; 
    console.log(`🔔 Orden: ${action.toUpperCase()} (${provider || 'HS'})`);

    try {
        if (action === 'scan') {
            // Paso 1: Buscar fechas
            const lista = await runScanner();
            res.json({ success: true, data: lista });
        } 
        else if (action === 'analyze') {
            // Paso 2: Leer fecha y cruzar con DB (Sin guardar)
            if (!url) throw new Error("Falta URL");
            const analisis = await runAnalyzer(url);
            res.json({ success: true, ...analisis });
        }
        else if (action === 'save_data') {
            // Paso 3: Guardar lo confirmado
            if (!dataToSave || !Array.isArray(dataToSave)) throw new Error("No hay datos");
            const count = await runSaver(dataToSave);
            res.json({ success: true, count });
        }
        else {
            throw new Error("Acción desconocida");
        }
    } catch (err) {
        console.error("❌ Error:", err.message);
        res.status(500).json({ success: false, message: err.message });
    }
});

// --- 1. ESCÁNER DE FECHAS ---
async function runScanner() {
    let browser = null;
    try {
        const { browser: b, page } = await loginAndGoToLiquidaciones();
        browser = b;

        const liquidaciones = await page.evaluate(() => {
            const links = Array.from(document.querySelectorAll('a'));
            const results = [];
            links.forEach(l => {
                const txt = l.innerText.trim();
                if (/\d{2}\/\d{2}\/\d{4}/.test(txt)) {
                    results.push({ fecha: txt, url: l.href });
                }
            });
            return results;
        });
        return liquidaciones;
    } catch (e) { throw e; } finally { if(browser) await browser.close(); }
}

// --- 2. ANALIZADOR (PREVISUALIZACIÓN) ---
async function runAnalyzer(targetUrl) {
    let browser = null;
    try {
        const { browser: b, page } = await loginAndGoToLiquidaciones(); 
        browser = b;

        console.log(`➡️ Analizando: ${targetUrl}`);
        await page.goto(targetUrl, { timeout: 60000 });
        await page.waitForTimeout(1500);

        // Buscar botón "Desglose Servicios"
        const botonPulsado = await page.evaluate(() => {
            const elementos = Array.from(document.querySelectorAll('input, button, a'));
            const target = elementos.find(el => {
                const txt = (el.value || el.innerText || "").toUpperCase();
                return txt.includes("SERVICIO") && txt.includes("DESGLOSE");
            });
            if (target) { target.click(); return true; }
            return false;
        });

        if (botonPulsado) await page.waitForTimeout(3000);

        // Extraer datos visuales
        const datosRaw = await page.evaluate(() => {
            const filas = Array.from(document.querySelectorAll('tr'));
            const datos = [];
            filas.forEach(tr => {
                const tds = tr.querySelectorAll('td');
                // Col 0: Servicio, Col 1: Dirección, Col 5: Saldo
                if (tds.length >= 6) {
                    const servicio = tds[0].innerText.trim();
                    const direccion = tds[1].innerText.trim();
                    const saldoRaw = tds[5].innerText.trim();
                    if (/^\d{5,}$/.test(servicio)) {
                        datos.push({ servicio, direccion, saldoRaw });
                    }
                }
            });
            return datos;
        });

        // Cruzar con Firebase (Lectura)
        const encontrados = [];
        const noEncontrados = [];

        if (db) {
            for (const item of datosRaw) {
                let cleanSaldo = item.saldoRaw.replace(/[^\d.-]/g, '');
                let importe = Math.abs(parseFloat(cleanSaldo) || 0);

                const q = await db.collection(APPOINTMENTS_COL).where("serviceNumber", "==", item.servicio).get();
                
                if (!q.empty) {
                    // Si hay duplicados, cogemos el primero o todos
                    q.forEach(doc => {
                        encontrados.push({
                            servicio: item.servicio,
                            direccion: item.direccion,
                            importe: importe,
                            docId: doc.id
                        });
                    });
                } else {
                    noEncontrados.push({
                        servicio: item.servicio,
                        direccion: item.direccion,
                        importe: importe
                    });
                }
            }
        }

        console.log(`✅ Análisis: ${encontrados.length} encontrados, ${noEncontrados.length} no encontrados.`);
        return { encontrados, noEncontrados };

    } catch (e) { throw e; } finally { if(browser) await browser.close(); }
}

// --- 3. GUARDADOR (RÁPIDO) ---
async function runSaver(items) {
    if (!db) return 0;
    const batch = db.batch();
    const nowISO = new Date().toISOString();
    let count = 0;

    items.forEach(item => {
        const ref = db.collection(APPOINTMENTS_COL).doc(item.docId);
        batch.update(ref, {
            paidAmount: item.importe,
            status: 'completed',
            paymentDate: nowISO,
            homeservePaymentStatus: 'paid_saldo',
            lastUpdatedByRobot: nowISO
        });
        count++;
    });

    await batch.commit();
    console.log(`💾 Guardados ${count} documentos en DB.`);
    return count;
}

// --- LOGIN ---
async function loginAndGoToLiquidaciones() {
    let user = "", pass = "";
    if (db) {
        const doc = await db.collection("providerCredentials").doc("homeserve").get();
        if (doc.exists) { user = doc.data().user; pass = doc.data().pass; }
    }
    const browser = await chromium.launch({ headless: true, args: ['--no-sandbox'] });
    const page = await browser.newPage();
    
    await page.goto('https://www.clientes.homeserve.es/cgi-bin/fccgi.exe?w3exec=PROF_PASS', { timeout: 60000 });
    if (await page.isVisible('input[name="CODIGO"]')) {
        await page.fill('input[name="CODIGO"]', user);
        await page.fill('input[type="password"]', pass);
        await page.keyboard.press('Enter');
        await page.waitForTimeout(4000);
    }
    await page.goto('https://www.clientes.homeserve.es/cgi-bin/fccgi.exe?w3exec=CONSULTALIQ_WEB');
    await page.waitForTimeout(2000);
    return { browser, page };
}

const PORT = process.env.PORT || 3000;
app.listen(PORT, () => console.log(`🚀 Server on port ${PORT}`));