script.js

import { initializeApp } from "https://www.gstatic.com/firebasejs/10.8.0/firebase-app.js";
import { initializeFirestore, persistentLocalCache, persistentMultipleTabManager, doc, getDoc, getDocs, collection, updateDoc, arrayUnion } from "https://www.gstatic.com/firebasejs/10.8.0/firebase-firestore.js";

const firebaseConfig = {
    apiKey: "AIzaSyC5mkT_JX0bGE0Ves_aY1ivRI3vdQuY7s4",
    authDomain: "notas-e1f61.firebaseapp.com",
    projectId: "notas-e1f61",
    storageBucket: "notas-e1f61.firebasestorage.app",
    messagingSenderId: "14068896226",
    appId: "1:14068896226:web:009f9cc8c573dfa33469bb",
    measurementId: "G-9BCWCKKT2M"
};

// Inicialización avanzada con caché local activa para evitar el bloqueo "offline"
const app = initializeApp(firebaseConfig);
const db = initializeFirestore(app, {
    localCache: persistentLocalCache({
        tabManager: persistentMultipleTabManager()
    })
});

// Elementos del DOM
const loginContainer = document.getElementById("login-container");
const dashboardContainer = document.getElementById("dashboard-container");
const studentView = document.getElementById("student-view");
const adminView = document.getElementById("admin-view");
const loginForm = document.getElementById("login-form");
const usernameInput = document.getElementById("username");
const passwordInput = document.getElementById("password");
const topStudentsList = document.getElementById("top-students-list");
const userDisplay = document.getElementById("user-display");
const userRoleText = document.getElementById("user-role-text");
const logoutBtn = document.getElementById("logout-btn");
const adminStudentsTbody = document.getElementById("admin-students-tbody");
const studentGradesList = document.getElementById("student-grades-list");
const studentAverage = document.getElementById("student-average");

function calculateAverage(gradesArray) {
    if (!gradesArray || !Array.isArray(gradesArray) || gradesArray.length === 0) return 1.0;
    const sum = gradesArray.reduce((acc, curr) => acc + curr, 0);
    return sum / gradesArray.length;
}

async function loadRanking() {
    try {
        topStudentsList.innerHTML = "";
        const querySnapshot = await getDocs(collection(db, "students"));
        const students = [];
        querySnapshot.forEach((doc) => {
            const data = doc.data();
            const grades = data.grades || [];
            const avg = calculateAverage(grades);
            students.push({ id: doc.id, name: data.name || doc.id, avg: avg });
        });
        students.sort((a, b) => b.avg - a.avg);
        students.forEach((student, index) => {
            const li = document.createElement("li");
            let badgeClass = "";
            if (index === 0) badgeClass = "gold";
            else if (index === 1) badgeClass = "silver";
            else if (index === 2) badgeClass = "bronze";
            li.innerHTML = `<span class="student-name">${student.name}</span><span class="student-badge ${badgeClass}">${student.avg.toFixed(1)}</span>`;
            topStudentsList.appendChild(li);
        });
    } catch (error) {
        console.error("Error en ranking: ", error);
    }
}

async function loadAdminTable() {
    try {
        adminStudentsTbody.innerHTML = "";
        const querySnapshot = await getDocs(collection(db, "students"));
        
        if (querySnapshot.empty) {
            adminStudentsTbody.innerHTML = "<tr><td colspan='6' style='text-align:center;'>No hay estudiantes registrados.</td></tr>";
            return;
        }

        querySnapshot.forEach((documentSnapshot) => {
            const data = documentSnapshot.data();
            const grades = data.grades || [];
            const avg = calculateAverage(grades);
            const tr = document.createElement("tr");
            tr.innerHTML = `
                <td>${data.name || "Sin nombre"}</td>
                <td>${documentSnapshot.id}</td>
                <td><span class="history-text">${grades.length > 0 ? grades.join(" | ") : "Sin notas"}</span></td>
                <td><strong>${avg.toFixed(1)}</strong></td>
                <td><input type="number" class="input-table-grade new-grade-input" min="1" max="5" step="0.1" placeholder="0.0"></td>
                <td><button class="btn-save">Añadir</button></td>
            `;
            const saveBtn = tr.querySelector(".btn-save");
            saveBtn.addEventListener("click", async () => {
                const inputField = tr.querySelector(".new-grade-input");
                let newGrade = parseFloat(inputField.value);
                if (isNaN(newGrade)) {
                    alert("Por favor ingresa una nota válida");
                    return;
                }
                if (newGrade < 1) newGrade = 1;
                if (newGrade > 5) newGrade = 5;
                await updateDoc(doc(db, "students", documentSnapshot.id), {
                    grades: arrayUnion(newGrade)
                });
                alert("Nueva nota añadida");
                await loadAdminTable();
                loadRanking();
            });
            adminStudentsTbody.appendChild(tr);
        });
    } catch (error) {
        adminStudentsTbody.innerHTML = `<tr><td colspan='6' style='color:red; text-align:center;'>Error: ${error.message}</td></tr>`;
    }
}

loginForm.addEventListener("submit", async (e) => {
    e.preventDefault();
    const user = usernameInput.value.trim();
    const pass = passwordInput.value.trim();

    // 1. LOGIN DE PROFESOR
    if (user === "admin" && pass === "1276") {
        loginContainer.classList.add("hidden");
        dashboardContainer.classList.remove("hidden");
        adminView.classList.remove("hidden");
        studentView.classList.add("hidden");
        userDisplay.textContent = "Administrador";
        userRoleText.textContent = "Rol: Profesor";
        await loadAdminTable();
        return; 
    } 

    // 2. LOGIN DE ESTUDIANTES
    try {
        const docRef = doc(db, "students", user);
        const docSnap = await getDoc(docRef);

        if (!docSnap.exists()) {
            alert("El código '" + user + "' no existe en la base de datos.");
            return;
        }

        const data = docSnap.data();
        
        if (data.password !== pass) {
            alert("Contraseña incorrecta.");
            return;
        }

        loginContainer.classList.add("hidden");
        dashboardContainer.classList.remove("hidden");
        studentView.classList.remove("hidden");
        adminView.classList.add("hidden");
        userDisplay.textContent = data.name || user;
        userRoleText.textContent = "Rol: Estudiante";
        const grades = data.grades || [];
        const avg = calculateAverage(grades);
        studentGradesList.textContent = grades.length > 0 ? grades.join(" , ") : "No tienes notas registradas";
        studentAverage.textContent = avg.toFixed(1);

    } catch (error) {
        alert("Error de conexión de Firebase: " + error.message);
    }
});

logoutBtn.addEventListener("click", () => {
    dashboardContainer.classList.add("hidden");
    loginContainer.classList.remove("hidden");
    loginForm.reset();
    loadRanking();
});

// Cargar Ranking Inicial
loadRanking();