const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');
const axios = require('axios');
const path = require('path');
const fs = require('fs');
const multer = require('multer');
// const { S3Client } = require('@aws-sdk/client-s3'); // Removed S3
// const { Upload } = require('@aws-sdk/lib-storage'); // Removed S3
const config = require('./config/index');
const remoteConfig = require('./services/remoteConfig');
const logger = require('./utils/logger');

const app = express();
const port = config.port;

app.use(cors());
app.use(bodyParser.json());

// 请求日志中间件
app.use((req, res, next) => {
    // 忽略静态资源请求日志，避免刷屏
    if (!req.url.startsWith('/uploads') && !req.url.startsWith('/public')) {
        logger.info('HTTP', `${req.method} ${req.url}`);
    }
    next();
});

// 配置静态文件服务，用于微信域名校验文件
// 请将下载的 MP_verify_xxx.txt 文件放入 server/public 目录
app.use(express.static(path.join(__dirname, 'public')));
// 配置上传文件的静态服务
app.use('/uploads', express.static(path.join(__dirname, 'uploads')));

// ==================================================================
// 公众号配置区域 (用于获取永久头像)
// ==================================================================
// 已移至 config.js

// Step 1: 小程序跳转到这里，服务器重定向到微信授权页
app.get('/auth/oa/login', (req, res) => {
    // 1. 尝试从远程配置获取动态域名
    const { agentid, gameid, channelid, marketid } = config.remoteConfig;
    const key = config.officialAccount.redirectDomainKey || 'auth_redirect_domain';
    
    let currentDomain = remoteConfig.getParaValue(key, agentid, gameid, channelid, marketid);
    
    if (!currentDomain) {
        return res.status(500).send('Configuration Error: No redirect domain available in remote config.');
    }
    
    // 3. 格式化域名 (确保有 https且无末尾斜杠)
    currentDomain = currentDomain.trim().replace(/\/$/, '');
    if (!currentDomain.startsWith('http')) {
        currentDomain = `https://${currentDomain}`;
    }

    // 这里的 redirect_uri 必须是 encodeURIComponent 后的完整 URL
    const redirectUri = encodeURIComponent(`${currentDomain}/auth/oa/callback`);
    const scope = 'snsapi_userinfo'; // 获取头像必须用 userinfo 作用域
    const url = `https://open.weixin.qq.com/connect/oauth2/authorize?appid=${config.officialAccount.appId}&redirect_uri=${redirectUri}&response_type=code&scope=${scope}&state=STATE#wechat_redirect`;
    
    // console.log('Redirecting to WeChat Auth:', url); // 打印跳转链接，方便调试
    logger.info('Auth', 'Redirecting to WeChat Auth:', url);
    res.redirect(url);
});

// Step 2: 微信回调，获取 code -> access_token -> userinfo -> 返回 HTML 给 web-view
app.get('/auth/oa/callback', async (req, res) => {
    const code = req.query.code;
    // console.log('WeChat Callback Code:', code); // 打印回调 Code
    logger.info('Auth', 'WeChat Callback Code:', code);

    if (!code) return res.send('Auth failed, no code');

    try {
        // 1. 获取 access_token
        const tokenUrl = `https://api.weixin.qq.com/sns/oauth2/access_token?appid=${config.officialAccount.appId}&secret=${config.officialAccount.appSecret}&code=${code}&grant_type=authorization_code`;
        // console.log('Requesting Token URL:', tokenUrl); // 打印 Token 请求链接 (注意：生产环境不要打印 Secret)
        logger.debug('Auth', 'Requesting Token URL (Secret Hidden)');

        const tokenRes = await axios.get(tokenUrl);
        // console.log('Token Response:', tokenRes.data); // 打印 Token 响应结果
        logger.debug('Auth', 'Token Response:', tokenRes.data);
        
        if (tokenRes.data.errcode) {
            return res.send('Token Error: ' + JSON.stringify(tokenRes.data));
        }

        const { access_token, openid } = tokenRes.data;

        // 2. 获取用户信息 (包含永久头像 headimgurl)
        const infoUrl = `https://api.weixin.qq.com/sns/userinfo?access_token=${access_token}&openid=${openid}&lang=zh_CN`;
        const infoRes = await axios.get(infoUrl);
        // console.log('User Info Response:', infoRes.data); // 打印用户信息响应
        logger.success('Auth', 'User Info Retrieved:', infoRes.data.nickname);

        const userInfo = infoRes.data; // { headimgurl, nickname, unionid, ... }

        // 3. 返回一个 HTML，利用 JSSDK 把数据传回小程序
        // 注意：wx.miniProgram.postMessage 只有在页面后退、销毁、分享时才会触发小程序的 bindmessage
        // 所以这里我们发送数据后，立即调用 navigateBack
        const html = `
        <!DOCTYPE html>
        <html>
        <head>
            <meta name="viewport" content="width=device-width, initial-scale=1.0">
            <title>正在同步...</title>
            <script type="text/javascript" src="https://res.wx.qq.com/open/js/jweixin-1.6.0.js"></script>
        </head>
        <body>
            <h3 style="text-align:center; margin-top: 50px;">正在同步微信头像...</h3>
            <script>
                function sendAndBack() {
                    // 发送消息给小程序
                    wx.miniProgram.postMessage({ 
                        data: ${JSON.stringify(userInfo)} 
                    });
                    // 跳回小程序上一页
                    wx.miniProgram.navigateBack();
                }

                if (window.WeixinJSBridge) {
                    sendAndBack();
                } else {
                    document.addEventListener('WeixinJSBridgeReady', sendAndBack, false);
                }
                // 保底策略
                setTimeout(sendAndBack, 1000);
            </script>
        </body>
        </html>
        `;
        res.send(html);

    } catch (error) {
        console.error(error);
        res.send('Auth error: ' + error.message);
    }
});

// 获取 AccessToken (简单实现，实际生产环境需要缓存 AccessToken)
async function getAccessToken() {
    const url = `https://api.weixin.qq.com/cgi-bin/token?grant_type=client_credential&appid=${config.miniProgram.appId}&secret=${config.miniProgram.appSecret}`;
    try {
        const response = await axios.get(url);
        if (response.data.errcode) {
            throw new Error(`获取 AccessToken 失败: ${response.data.errmsg}`);
        }
        return response.data.access_token;
    } catch (error) {
        console.error('Get AccessToken Error:', error.message);
        throw error;
    }
}

// 1. 登录接口：换取 OpenID 和 UnionID
app.post('/api/login', async (req, res) => {
    const { code } = req.body;
    if (!code) {
        return res.status(400).json({ error: 'Code is required' });
    }

    // 如果用户没有配置 AppID，返回模拟数据
    if (config.miniProgram.appId === 'YOUR_APP_ID') {
        // console.log('未配置 AppID，返回模拟登录数据');
        return res.json({
            openid: 'mock_openid_' + Date.now(),
            unionid: 'mock_unionid_' + Date.now(),
            session_key: 'mock_session_key'
        });
    }

    const url = `https://api.weixin.qq.com/sns/jscode2session?appid=${config.miniProgram.appId}&secret=${config.miniProgram.appSecret}&js_code=${code}&grant_type=authorization_code`;

    try {
        const response = await axios.get(url);
        if (response.data.errcode) {
            return res.status(500).json({ error: response.data.errmsg });
        }
        // 返回 openid, unionid (如果有), session_key
        res.json(response.data);
    } catch (error) {
        res.status(500).json({ error: error.message });
    }
});

// 2. 获取手机号接口
app.post('/api/getPhoneNumber', async (req, res) => {
    const { code } = req.body;
    if (!code) {
        return res.status(400).json({ error: 'Code is required' });
    }

    // 如果用户没有配置 AppID，返回模拟数据
    if (config.miniProgram.appId === 'YOUR_APP_ID') {
        // console.log('未配置 AppID，返回模拟手机号');
        return res.json({
            phoneNumber: '13800138000',
            purePhoneNumber: '13800138000',
            countryCode: '86',
            watermark: { timestamp: Date.now(), appid: config.miniProgram.appId }
        });
    }

    try {
        const accessToken = await getAccessToken();
        const url = `https://api.weixin.qq.com/wxa/business/getuserphonenumber?access_token=${accessToken}`;
        
        const response = await axios.post(url, { code });
        
        if (response.data.errcode === 0) {
            // 成功获取
            res.json(response.data.phone_info);
        } else {
            res.status(500).json({ error: response.data.errmsg, errcode: response.data.errcode });
        }
    } catch (error) {
        console.error('Get Phone Number Error:', error);
        res.status(500).json({ error: error.message });
    }
});

// 缓存 game_server_http
let cachedGameServerHttp = null;

// 监听远程配置更新
remoteConfig.onUpdate(() => {
    const { agentid, gameid, channelid, marketid } = config.remoteConfig;
    const newValue = remoteConfig.getParaValue('game_server_http', agentid, gameid, channelid, marketid);
    
    if (newValue) {
        cachedGameServerHttp = newValue;
        // logger.info('Config', 'Updated cached game_server_http:', cachedGameServerHttp);
    } else {
        logger.warn('Config', 'game_server_http not found in new config');
    }
});

// 3. 文件上传接口 (本地存储)
// 确保存储目录存在
const uploadDir = path.join(__dirname, 'uploads');
if (!fs.existsSync(uploadDir)) {
    fs.mkdirSync(uploadDir, { recursive: true });
}

const storage = multer.diskStorage({
    destination: function (req, file, cb) {
        cb(null, uploadDir)
    },
    filename: function (req, file, cb) {
        const fileExtension = path.extname(file.originalname) || '.jpg';
        const fileName = `${Date.now()}_${Math.random().toString(36).substr(2, 9)}${fileExtension}`;
        cb(null, fileName)
    }
});

const upload = multer({ 
    storage: storage,
    fileFilter: (req, file, cb) => {
        if (config.enableAvatarUpload === false) {
            // 如果配置关闭了上传，拒绝文件
            return cb(null, false);
        }
        cb(null, true);
    }
});

app.post('/api/upload', upload.single('file'), (req, res) => {
    if (config.enableAvatarUpload === false) {
        return res.status(403).json({ error: 'Avatar upload is disabled' });
    }

    if (!req.file) {
        return res.status(400).json({ error: 'No file uploaded' });
    }

    try {
        // 构造访问链接
        const protocol = req.protocol;
        const host = req.get('host');
        const fileUrl = `${protocol}://${host}/uploads/${req.file.filename}`;
        
        logger.success('Upload', 'File uploaded successfully:', fileUrl);
        res.json({ url: fileUrl });
    } catch (error) {
        logger.error('Upload', 'Upload Error:', error);
        res.status(500).json({ error: 'Upload failed: ' + error.message });
    }
});

// 4. 提交用户信息接口 (真实保存到游戏服务器)
app.post('/api/saveUserInfo', async (req, res) => {
    const userInfo = req.body;
    logger.divider('Save User Info');
    logger.info('API', 'Received User Info:', userInfo.nickName);

    try {
        // 1. 使用缓存的 game_server_http
        if (!cachedGameServerHttp) {
            // 如果缓存为空（例如启动时首次获取尚未完成），尝试手动获取一次
            const { agentid, gameid, channelid, marketid } = config.remoteConfig;
            cachedGameServerHttp = remoteConfig.getParaValue('game_server_http', agentid, gameid, channelid, marketid);
        }

        if (!cachedGameServerHttp) {
            logger.error('Config', 'game_server_http not found');
            return res.status(500).json({ error: 'Configuration error: game_server_http not found' });
        }

        // 确保 URL 格式正确
        const targetUrl = cachedGameServerHttp.startsWith('http') ? cachedGameServerHttp : `http://${cachedGameServerHttp}`;

        // 2. 构造请求数据
        const { agentid, gameid, channelid, marketid } = config.remoteConfig;
        const payload = {
            "app": "youle",
            "route": "agent",
            "rpc": "bind_player_wechat",
            "data": {
                "agentid": agentid,
                "channelid": channelid,
                "marketid": marketid,
                "gameid": gameid,
                "openid": userInfo.openid,
                "unionid": userInfo.unionid,
                "nickname": userInfo.nickName,
                "avatar": userInfo.avatarUrl,
                "sex": userInfo.gender, 
                "province": userInfo.province,
                "city": userInfo.city,
                "telphone": userInfo.phoneNumber
            }
        };

        // --- Debug: 生成可粘贴到浏览器的 GET 链接 ---
        // try {
        //     const debugQuery = `data=${encodeURIComponent(JSON.stringify(payload))}`;
        //     const debugUrl = `${targetUrl}?${debugQuery}`;
        //     console.log('\n[Debug] Request URL for Browser:');
        //     console.log(debugUrl);
        //     console.log('');
        // } catch (e) {
        //     console.error('[Debug] Failed to generate debug URL:', e);
        // }
        // -------------------------------------------

        // 3. 发送请求
        const bodyData = 'data=' + JSON.stringify(payload);
        
        logger.info('GameServer', 'Sending bind_player_wechat request...');
        logger.debug('GameServer', 'Payload:', payload);

        const response = await axios.post(targetUrl, bodyData, {
            headers: {
                'Content-Type': 'application/x-www-form-urlencoded'
            }
        });
        logger.info('GameServer', 'Response received');
        logger.debug('GameServer', 'Response Data:', response.data);

        const gameResult = response.data?.data?.result;
        const isSuccess = gameResult !== -1;
        res.json({ success: isSuccess, message: response.data?.data?.msg, data: response.data });

    } catch (error) {
        logger.error('API', 'Save User Info Error:', error.message);
        res.status(500).json({ success: false, message: '用户信息保存失败: ' + error.message, error: error.message });
    }
});

// 5. 玩家登录接口
app.post('/api/playerLogin', async (req, res) => {
    const userInfo = req.body;
    logger.divider('Player Login');
    logger.info('API', 'Received Login Request:', userInfo.nickName);

    try {
        if (!cachedGameServerHttp) {
            const { agentid, gameid, channelid, marketid } = config.remoteConfig;
            cachedGameServerHttp = remoteConfig.getParaValue('game_server_http', agentid, gameid, channelid, marketid);
        }

        if (!cachedGameServerHttp) {
            return res.status(500).json({ error: 'Configuration error: game_server_http not found' });
        }

        const targetUrl = cachedGameServerHttp.startsWith('http') ? cachedGameServerHttp : `http://${cachedGameServerHttp}`;
        const { agentid, gameid, channelid, marketid } = config.remoteConfig;
        
        const payload = {
            "app": "youle",
            "route": "agent",
            "rpc": "player_login",
            "data": {
                "agentid": agentid,
                "channelid": channelid,
                "marketid": marketid,
                "gameid": gameid,
                "openid": userInfo.openid,
                "unionid": userInfo.unionid,
                "nickname": userInfo.nickName,
                "avatar": userInfo.avatarUrl,
                "sex": userInfo.gender,
                "province": userInfo.province,
                "city": userInfo.city,
                "version": userInfo.version,
                "telphone": userInfo.phoneNumber,
                "smmcode": userInfo.verificationCode,
                "telphoneAuto": userInfo.telphoneAuto,
                "playerid": userInfo.playerid,
            }
        };

        // --- Debug: 生成可粘贴到浏览器的 GET 链接 ---
        // try {
        //     const debugQuery = `data=${encodeURIComponent(JSON.stringify(payload))}`;
        //     const debugUrl = `${targetUrl}?${debugQuery}`;
        //     console.log('\n[Debug] Request URL for Browser:');
        //     console.log(debugUrl);
        //     console.log('');
        // } catch (e) {
        //     console.error('[Debug] Failed to generate debug URL:', e);
        // }
        // -------------------------------------------

        const bodyData = 'data=' + JSON.stringify(payload);
        logger.info('GameServer', 'Sending player_login request...');
        logger.debug('GameServer', 'Payload:', payload);

        const response = await axios.post(targetUrl, bodyData, {
            headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
        });
        logger.info('GameServer', 'Login Response received');
        logger.debug('GameServer', 'Response Data:', response.data);

        res.json(response.data);

    } catch (error) {
        logger.error('API', 'Player Login Error:', error.message);
        res.status(500).json({ error: '登录失败: ' + error.message });
    }
});

// 6. 获取验证码接口
app.post('/api/getPhoneCode', async (req, res) => {
    const { phonenum } = req.body;
    logger.divider('Get Phone Code');
    logger.info('API', 'Received GetCode Request:', phonenum);

    try {
        if (!cachedGameServerHttp) {
            const { agentid, gameid, channelid, marketid } = config.remoteConfig;
            cachedGameServerHttp = remoteConfig.getParaValue('game_server_http', agentid, gameid, channelid, marketid);
        }

        if (!cachedGameServerHttp) {
            return res.status(500).json({ error: 'Configuration error: game_server_http not found' });
        }

        const targetUrl = cachedGameServerHttp.startsWith('http') ? cachedGameServerHttp : `http://${cachedGameServerHttp}`;
        const { agentid } = config.remoteConfig;
        
        const payload = {
            "app": "youle",
            "route": "agent",
            "rpc": "send_phone_code_wechat",
            "data": {
                "agentid": agentid,
                "phonenum": phonenum
            }
        };

        // --- Debug: 生成可粘贴到浏览器的 GET 链接 ---
        // try {
        //     const debugQuery = `data=${encodeURIComponent(JSON.stringify(payload))}`;
        //     const debugUrl = `${targetUrl}?${debugQuery}`;
        //     console.log('\n[Debug] Request URL for Browser:');
        //     console.log(debugUrl);
        //     console.log('');
        // } catch (e) {
        //     console.error('[Debug] Failed to generate debug URL:', e);
        // }
        // -------------------------------------------

        const bodyData = 'data=' + JSON.stringify(payload);
        logger.info('GameServer', 'Sending get_phone_code_wechat request...');

        const response = await axios.post(targetUrl, bodyData, {
            headers: { 'Content-Type': 'application/x-www-form-urlencoded' }
        });
        logger.info('GameServer', 'GetCode Response received');
        logger.debug('GameServer', 'Response Data:', response.data);

        res.json(response.data);

    } catch (error) {
        logger.error('API', 'Get Phone Code Error:', error.message);
        res.status(500).json({ error: '获取随机数失败: ' + error.message });
    }
});

// 启动远程配置更新
remoteConfig.start();

app.listen(port, () => {
    logger.divider();
    logger.success('System', `Server running at http://localhost:${port}`);
    logger.info('System', 'Press Ctrl+C to stop');
});