// src/services/authService.js
/**
 * 认证服务层 - 处理所有认证相关的 API 调用
 */

const isProduction = process.env.NODE_ENV === 'production';
const API_BASE_URL = isProduction ? "" : process.env.REACT_APP_API_URL;

/**
 * 统一的 API 请求处理
 * @param {string} url - 请求路径
 * @param {object} options - fetch 选项
 * @returns {Promise} - 响应数据
 */
const apiRequest = async (url, options = {}) => {
    try {
        const response = await fetch(`${API_BASE_URL}${url}`, {
            ...options,
            headers: {
                'Content-Type': 'application/json',
                ...options.headers,
            },
            credentials: 'include', // 包含 cookies
        });

        // 检查响应是否为 JSON
        const contentType = response.headers.get('content-type');
        const isJson = contentType && contentType.includes('application/json');

        if (!response.ok) {
            let errorMessage = `HTTP error! status: ${response.status}`;
            if (isJson) {
                try {
                    const errorData = await response.json();
                    errorMessage = errorData.error || errorData.message || errorMessage;
                } catch (parseError) {
                    console.warn('Failed to parse error response as JSON');
                }
            }
            throw new Error(errorMessage);
        }

        // 安全地解析 JSON 响应
        if (isJson) {
            try {
                return await response.json();
            } catch (parseError) {
                console.error('Failed to parse response as JSON:', parseError);
                throw new Error('服务器响应格式错误');
            }
        } else {
            throw new Error('服务器响应不是 JSON 格式');
        }
    } catch (error) {
        console.error(`Auth API request failed for ${url}:`, error);
        // 如果是网络错误，提供更友好的提示
        if (error.message === 'Failed to fetch' || error.name === 'TypeError') {
            throw new Error('网络连接失败，请检查网络设置');
        }
        throw error;
    }
};

export const authService = {
    /**
     * 获取微信二维码授权链接（PC扫码登录）
     * @returns {Promise<{auth_url: string, session_id: string}>}
     */
    getWechatQRCode: async () => {
        return await apiRequest('/api/auth/wechat/qrcode');
    },

    /**
     * 获取微信H5授权链接（移动端网页授权）
     * @param {string} redirectUrl - 授权成功后的回调地址
     * @returns {Promise<{auth_url: string}>}
     */
    getWechatH5AuthUrl: async (redirectUrl) => {
        return await apiRequest('/api/auth/wechat/h5-auth', {
            method: 'POST',
            body: JSON.stringify({ redirect_url: redirectUrl }),
        });
    },

    /**
     * 微信H5授权回调处理
     * @param {string} code - 微信授权code
     * @param {string} state - 状态参数
     * @returns {Promise<{success: boolean, user?: object, token?: string}>}
     */
    handleWechatH5Callback: async (code, state) => {
        return await apiRequest('/api/auth/wechat/h5-callback', {
            method: 'POST',
            body: JSON.stringify({ code, state }),
        });
    },

    /**
     * 检查微信扫码状态
     * @param {string} sessionId - 会话ID
     * @returns {Promise<{status: string, user_info?: object}>}
     */
    checkWechatStatus: async (sessionId) => {
        return await apiRequest('/api/auth/wechat/check', {
            method: 'POST',
            body: JSON.stringify({ session_id: sessionId }),
        });
    },

    /**
     * 使用微信 session 登录
     * @param {string} sessionId - 会话ID
     * @returns {Promise<{success: boolean, user?: object, token?: string}>}
     */
    loginWithWechat: async (sessionId) => {
        return await apiRequest('/api/auth/login/wechat', {
            method: 'POST',
            body: JSON.stringify({ session_id: sessionId }),
        });
    },
};

/**
 * 微信状态常量
 */
export const WECHAT_STATUS = {
    NONE: 'none',
    WAITING: 'waiting',
    SCANNED: 'scanned',
    AUTHORIZED: 'authorized',
    LOGIN_SUCCESS: 'login_success',
    REGISTER_SUCCESS: 'register_success',
    EXPIRED: 'expired',
};

/**
 * 状态提示信息映射
 */
export const STATUS_MESSAGES = {
    [WECHAT_STATUS.WAITING]: '请使用微信扫码',
    [WECHAT_STATUS.SCANNED]: '扫码成功，请在手机上确认',
    [WECHAT_STATUS.AUTHORIZED]: '授权成功，正在登录...',
    [WECHAT_STATUS.EXPIRED]: '二维码已过期',
};

export default authService;