/**
 * 用户认证逻辑
 * 处理登录、注册表单的提交和验证
 */

// API配置
const API_BASE_URL = 'http://192.168.1.17:8080/api';
const AUTH_TOKEN_KEY = 'duoduo_auth_token';
const USER_INFO_KEY = 'duoduo_user_info';

// 专业大类数据
let professionalCategories = [];

/**
 * 加载专业大类数据
 */
async function loadProfessionalCategories() {
    try {
        const response = await fetch('/专业大类.json');
        professionalCategories = await response.json();

        // 填充注册表单的下拉选择框
        const selectElement = document.getElementById('register-professional-category');
        if (selectElement) {
            professionalCategories.forEach(category => {
                const option = document.createElement('option');
                option.value = category.大类代码;
                option.textContent = category.大类名称;
                selectElement.appendChild(option);
            });
        }
    } catch (error) {
        console.error('加载专业大类失败:', error);
    }
}

// ==================== 工具函数 ====================

/**
 * 显示错误信息
 */
function showError(elementId, message) {
    const errorElement = document.getElementById(elementId);
    errorElement.textContent = message;
    errorElement.style.display = 'block';
}

/**
 * 显示成功信息
 */
function showSuccess(elementId, message) {
    const successElement = document.getElementById(elementId);
    successElement.textContent = message;
    successElement.style.display = 'block';
}

/**
 * 隐藏消息
 */
function hideMessage(elementId) {
    const element = document.getElementById(elementId);
    element.textContent = '';
    element.style.display = 'none';
}

/**
 * 隐藏所有消息
 */
function hideAllMessages() {
    hideMessage('login-error-msg');
    hideMessage('register-error-msg');
    hideMessage('register-success-msg');
}

// ==================== 表单验证 ====================

/**
 * 验证登录表单
 */
function validateLoginForm(username, password) {
    if (!username || !password) {
        return '用户名和密码不能为空';
    }
    return null;
}

/**
 * 验证注册表单
 */
function validateRegisterForm(username, password, confirmPassword, email, phone) {
    // 真实姓名验证
    if (!username) {
        return '真实姓名不能为空';
    }
    if (username.length < 2 || username.length > 10) {
        return '姓名长度必须在2-10个字符之间';
    }

    // 密码验证
    if (!password) {
        return '密码不能为空';
    }
    if (password.length < 6) {
        return '密码长度至少为6个字符';
    }

    // 确认密码验证
    if (password !== confirmPassword) {
        return '两次输入的密码不一致';
    }

    // 邮箱验证（如果填写）
    if (email && email.trim() !== '') {
        const emailRegex = /^[^\s@]+@[^\s@]+\.[^\s@]+$/;
        if (!emailRegex.test(email)) {
            return '邮箱格式不正确';
        }
    }

    // 手机号验证（必填）
    if (!phone || phone.trim() === '') {
        return '手机号码不能为空';
    }
    const phoneRegex = /^1[3-9]\d{9}$/;
    if (!phoneRegex.test(phone)) {
        return '手机号格式不正确';
    }

    return null;
}

// ==================== 登录功能 ====================

/**
 * 处理用户登录
 */
async function handleLogin() {
    // 隐藏之前的错误信息
    hideAllMessages();

    // 获取表单数据
    const username = document.getElementById('login-username').value.trim();
    const password = document.getElementById('login-password').value;

    // 前端验证
    const validationError = validateLoginForm(username, password);
    if (validationError) {
        showError('login-error-msg', validationError);
        return;
    }

    // 禁用提交按钮，显示加载状态
    const submitBtn = document.getElementById('login-submit-btn');
    const originalText = submitBtn.textContent;
    submitBtn.disabled = true;
    submitBtn.textContent = '登录中...';
    submitBtn.style.opacity = '0.7';

    try {
        // 调用登录API
        const response = await fetch(`${API_BASE_URL}/auth/login`, {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify({ username, password })
        });

        const data = await response.json();

        if (data.success) {
            // 保存token和用户信息到localStorage
            localStorage.setItem(AUTH_TOKEN_KEY, data.data.token);
            localStorage.setItem(USER_INFO_KEY, JSON.stringify(data.data.user));

            // 登录成功，跳转到首页
            window.location.href = 'index.html';
        } else {
            // 显示后端返回的错误信息
            showError('login-error-msg', data.message || '登录失败，请重试');
        }
    } catch (error) {
        console.error('登录错误:', error);
        showError('login-error-msg', '网络错误，请检查服务器是否运行');
    } finally {
        // 恢复按钮状态
        submitBtn.disabled = false;
        submitBtn.textContent = originalText;
        submitBtn.style.opacity = '1';
    }
}

// ==================== 注册功能 ====================

/**
 * 处理用户注册
 */
async function handleRegister() {
    // 隐藏之前的消息
    hideAllMessages();

    // 获取表单数据
    const username = document.getElementById('register-username').value.trim();
    const password = document.getElementById('register-password').value;
    const confirmPassword = document.getElementById('register-password-confirm').value;
    const email = document.getElementById('register-email').value.trim();
    const phone = document.getElementById('register-phone').value.trim();
    const professionalCategoryCode = document.getElementById('register-professional-category').value;

    // 前端验证
    const validationError = validateRegisterForm(username, password, confirmPassword, email, phone);
    if (validationError) {
        showError('register-error-msg', validationError);
        return;
    }

    // 禁用提交按钮，显示加载状态
    const submitBtn = document.getElementById('register-submit-btn');
    const originalText = submitBtn.textContent;
    submitBtn.disabled = true;
    submitBtn.textContent = '注册中...';
    submitBtn.style.opacity = '0.7';

    try {
        // 调用注册API
        const requestBody = { username, password };
        if (email) requestBody.email = email;
        if (phone) requestBody.phone = phone;
        // 如果选择了专业大类，添加到请求体
        if (professionalCategoryCode) {
            requestBody.professional_category_code = professionalCategoryCode;
            const category = professionalCategories.find(c => c.大类代码 === professionalCategoryCode);
            if (category) {
                requestBody.professional_category = category.大类名称;
            }
        }

        const response = await fetch(`${API_BASE_URL}/auth/register`, {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify(requestBody)
        });

        const data = await response.json();

        if (data.success) {
            // 显示成功提示
            showSuccess('register-success-msg', '注册成功！正在跳转到登录...');

            // 2秒后切换到登录表单并预填充用户名
            setTimeout(() => {
                // 切换到登录表单
                switchToLogin();

                // 预填充用户名
                document.getElementById('login-username').value = username;

                // 清空注册表单
                document.getElementById('register-username').value = '';
                document.getElementById('register-password').value = '';
                document.getElementById('register-password-confirm').value = '';
                document.getElementById('register-email').value = '';
                document.getElementById('register-phone').value = '';

                hideAllMessages();
            }, 2000);
        } else {
            // 显示后端返回的错误信息
            showError('register-error-msg', data.message || '注册失败，请重试');
        }
    } catch (error) {
        console.error('注册错误:', error);
        showError('register-error-msg', '网络错误，请检查服务器是否运行');
    } finally {
        // 恢复按钮状态
        submitBtn.disabled = false;
        submitBtn.textContent = originalText;
        submitBtn.style.opacity = '1';
    }
}

// ==================== 表单切换功能 ====================

/**
 * 切换到注册表单
 */
function switchToRegister() {
    hideAllMessages();

    const loginContainer = document.getElementById('login-form-container');
    const registerContainer = document.getElementById('register-form-container');

    // 隐藏登录
    loginContainer.style.opacity = '0';
    setTimeout(() => {
        loginContainer.classList.add('hidden');
        // 显示注册
        registerContainer.classList.remove('hidden');
        registerContainer.classList.add('fade-in');
        registerContainer.style.opacity = '1';
    }, 300);
}

/**
 * 切换到登录表单
 */
function switchToLogin() {
    hideAllMessages();

    const loginContainer = document.getElementById('login-form-container');
    const registerContainer = document.getElementById('register-form-container');

    // 隐藏注册
    registerContainer.classList.remove('fade-in');
    registerContainer.style.opacity = '0';

    setTimeout(() => {
        registerContainer.classList.add('hidden');
        registerContainer.style.opacity = '1';

        // 显示登录
        loginContainer.classList.remove('hidden');
        loginContainer.style.opacity = '1';
        loginContainer.classList.add('fade-in');
    }, 300);
}

// ==================== 页面初始化 ====================

document.addEventListener('DOMContentLoaded', () => {
    // 加载专业大类数据
    loadProfessionalCategories();

    // 检查是否已登录
    const token = localStorage.getItem(AUTH_TOKEN_KEY);
    if (token) {
        // 已登录，直接跳转到首页
        window.location.href = 'index.html';
        return;
    }

    // 绑定切换按钮事件
    document.getElementById('switch-to-register').addEventListener('click', switchToRegister);
    document.getElementById('switch-to-login').addEventListener('click', switchToLogin);

    // 绑定表单提交事件（通过form的onsubmit已经绑定，这里只是确保）
    // 表单已通过内联 onsubmit 绑定
});