script.js

// Data storage
let students = [];
let rooms = Array(50).fill(null);
let users = JSON.parse(localStorage.getItem('users')) || {
    students: [],
    admins: []
};
let currentUser = null;

// Show/hide sections
function showSection(sectionId) {
    const sections = currentUser ? 
        document.querySelectorAll('#main-container section') :
        document.querySelectorAll('#auth-container section');
    
    sections.forEach(section => section.classList.remove('active'));
    document.getElementById(sectionId).classList.add('active');
    
    if (currentUser) {
        updateDashboard();
        updateRoomList();
        document.getElementById('registerBtn').classList.toggle('hidden', currentUser.type !== 'admin');
    }
}

// Login
document.getElementById('loginForm').addEventListener('submit', function(e) {
    e.preventDefault();
    const userType = document.getElementById('userType').value;
    const id = document.getElementById('loginId').value;
    const password = document.getElementById('loginPassword').value;
    const messageDiv = document.getElementById('loginMessage');

    const userList = users[userType + 's'];
    const user = userList.find(u => u.id === id && u.password === password);

    if (user) {
        currentUser = { ...user, type: userType };
        document.getElementById('auth-container').style.display = 'none';
        document.getElementById('main-container').style.display = 'block';
        showSection('dashboard');
    } else {
        messageDiv.textContent = 'Invalid credentials!';
    }
});

// Signup
document.getElementById('signupForm').addEventListener('submit', function(e) {
    e.preventDefault();
    const userType = document.getElementById('signupUserType').value;
    const id = document.getElementById('signupId').value;
    const name = document.getElementById('signupName').value;
    const email = document.getElementById('signupEmail').value;
    const password = document.getElementById('signupPassword').value;
    const messageDiv = document.getElementById('signupMessage');

    if (users[userType + 's'].some(u => u.id === id)) {
        messageDiv.textContent = 'ID already exists!';
        return;
    }

    const newUser = { id, name, email, password };
    users[userType + 's'].push(newUser);
    localStorage.setItem('users', JSON.stringify(users));
    messageDiv.textContent = 'Sign up successful! Please login.';
    this.reset();
});

// Logout
function logout() {
    currentUser = null;
    document.getElementById('main-container').style.display = 'none';
    document.getElementById('auth-container').style.display = 'block';
    showSection('login');
}

// Handle student registration (admin only)
document.getElementById('studentForm').addEventListener('submit', function(e) {
    e.preventDefault();
    if (currentUser.type !== 'admin') return;

    const student = {
        name: document.getElementById('studentName').value,
        id: document.getElementById('studentId').value,
        email: document.getElementById('studentEmail').value,
        year: document.getElementById('studentYear').value,
        room: null
    };

    if (students.some(s => s.id === student.id)) {
        document.getElementById('registrationMessage').textContent = 'Student ID already exists!';
        return;
    }

    students.push(student);
    this.reset();
    document.getElementById('registrationMessage').textContent = 'Student registered successfully!';
    updateDashboard();
});

// Room allocation
function allocateRoom() {
    if (!currentUser) return;

    const studentId = document.getElementById('allocateStudentId').value;
    const roomNum = parseInt(document.getElementById('roomNumber').value) - 1;
    const messageDiv = document.getElementById('allocationMessage');

    if (!studentId || isNaN(roomNum) || roomNum < 0 || roomNum >= 50) {
        messageDiv.textContent = 'Please enter valid student ID and room number!';
        return;
    }

    const student = students.find(s => s.id === studentId);
    if (!student) {
        messageDiv.textContent = 'Student not found!';
        return;
    }

    if (rooms[roomNum]) {
        messageDiv.textContent = 'Room already occupied!';
        return;
    }

    if (student.room !== null) {
        rooms[student.room] = null;
    }
    rooms[roomNum] = studentId;
    student.room = roomNum;
    messageDiv.textContent = `Room ${roomNum + 1} allocated to ${student.name}!`;
    updateDashboard();
    updateRoomList();
}

// Update dashboard stats
function updateDashboard() {
    const totalStudents = students.length;
    const occupiedRooms = rooms.filter(room => room !== null).length;
    const availableRooms = 50 - occupiedRooms;

    document.getElementById('totalStudents').textContent = totalStudents;
    document.getElementById('occupiedRooms').textContent = occupiedRooms;
    document.getElementById('availableRooms').textContent = availableRooms;
}

// Update room list display
function updateRoomList() {
    const roomList = document.getElementById('roomList');
    roomList.innerHTML = '<h3>Room Status</h3>';
    
    rooms.forEach((studentId, index) => {
        const status = studentId ? 
            `Room ${index + 1}: Occupied by ${students.find(s => s.id === studentId).name}` :
            `Room ${index + 1}: Available`;
        const p = document.createElement('p');
        p.textContent = status;
        roomList.appendChild(p);
    });
}

// Initialize
showSection('login');