window.onload = function() {
    autoLogin();
};

var checkInfo = {};

checkInfo.checkUsername = function() {
    let username = document.getElementById('username').value;
    if (username.length < 1) {
        document.getElementById('usernameError').textContent = '用户名不能为空';
        return false;
    }
    document.getElementById('usernameError').textContent = '';
    return true;
}

checkInfo.checkPassword = function() {
    let password = document.getElementById('password').value;
    let regexPassword = /^[A-Za-z0-9\W_]{6,20}$/;
    if (!regexPassword.test(password)) {
        document.getElementById('loginError').textContent = "密码须为长度为6-20位字母、数字或符号";
        return false;
    }
    document.getElementById('loginError').textContent = '';
    return true;
}

function submitForm() {
    if (checkInfo.checkUsername() && checkInfo.checkPassword()) {
        document.getElementById('encryptedPassword').value = md5(
            document.getElementById('password').value
        );
        login();
        return true;
    }
    return false;
}

// 登录函数
async function login() {
    const username = document.getElementById('username').value;
    const encryptedPassword = document.getElementById('encryptedPassword').value;
    try {
        const response = await fetch('/login', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({ username: username, password: encryptedPassword }),
            credentials: 'include'  // 确保请求包含凭据（cookies）
        });
        const data = await response.json();
        if (response.ok) {
            alert('登录成功');
            // 自动跳转到主页
            window.location.href = data.redirect;
        } else {
            document.getElementById('loginError').textContent = data.message;
        }
    } catch (error) {
        alert('数据库错误，请稍后再试');
    }
}

// 自动登录函数
async function autoLogin() {
    const token = localStorage.getItem('token');
    if (token) {
        const response = await fetch('/index', {
            headers: {
                'Authorization': 'Bearer ' + token
            }
        });
        if (response.ok) {
            document.getElementById('content').innerText = '已自动登录';
        } else {
            document.getElementById('content').innerText = '自动登录失败';
        }
    }
}