feat: 添加多模型支持和OpenAI兼容接口

- 新增 Gemini 模型支持和账户管理功能
- 实现 OpenAI 格式到 Claude/Gemini 的请求转换
- 添加自动 token 刷新服务，支持提前刷新策略
- 增强 Web 管理界面，支持 Gemini 账户管理
- 优化 token 显示，添加掩码功能
- 完善日志记录和错误处理

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

src/routes/geminiRoutes.js

@@ -0,0 +1,275 @@
+const express = require('express');
+const router = express.Router();
+const logger = require('../utils/logger');
+const { authenticateApiKey } = require('../middleware/auth');
+const geminiAccountService = require('../services/geminiAccountService');
+const { sendGeminiRequest, getAvailableModels } = require('../services/geminiRelayService');
+const crypto = require('crypto');
+
+// 生成会话哈希
+function generateSessionHash(req) {
+  const sessionData = [
+    req.headers['user-agent'],
+    req.ip,
+    req.headers['x-api-key']?.substring(0, 10)
+  ].filter(Boolean).join(':');
+  
+  return crypto.createHash('sha256').update(sessionData).digest('hex');
+}
+
+// 检查 API Key 权限
+function checkPermissions(apiKeyData, requiredPermission = 'gemini') {
+  const permissions = apiKeyData.permissions || 'all';
+  return permissions === 'all' || permissions === requiredPermission;
+}
+
+// Gemini 消息处理端点
+router.post('/messages', authenticateApiKey, async (req, res) => {
+  const startTime = Date.now();
+  let abortController = null;
+  
+  try {
+    const apiKeyData = req.apiKeyData;
+    
+    // 检查权限
+    if (!checkPermissions(apiKeyData, 'gemini')) {
+      return res.status(403).json({
+        error: {
+          message: 'This API key does not have permission to access Gemini',
+          type: 'permission_denied'
+        }
+      });
+    }
+    
+    // 提取请求参数
+    const {
+      messages,
+      model = 'gemini-2.0-flash-exp',
+      temperature = 0.7,
+      max_tokens = 4096,
+      stream = false
+    } = req.body;
+    
+    // 验证必需参数
+    if (!messages || !Array.isArray(messages) || messages.length === 0) {
+      return res.status(400).json({
+        error: {
+          message: 'Messages array is required',
+          type: 'invalid_request_error'
+        }
+      });
+    }
+    
+    // 生成会话哈希用于粘性会话
+    const sessionHash = generateSessionHash(req);
+    
+    // 选择可用的 Gemini 账户
+    const account = await geminiAccountService.selectAvailableAccount(
+      apiKeyData.id,
+      sessionHash
+    );
+    
+    if (!account) {
+      return res.status(503).json({
+        error: {
+          message: 'No available Gemini accounts',
+          type: 'service_unavailable'
+        }
+      });
+    }
+    
+    logger.info(`Using Gemini account: ${account.id} for API key: ${apiKeyData.id}`);
+    
+    // 标记账户被使用
+    await geminiAccountService.markAccountUsed(account.id);
+    
+    // 创建中止控制器
+    abortController = new AbortController();
+    
+    // 处理客户端断开连接
+    req.on('close', () => {
+      if (abortController && !abortController.signal.aborted) {
+        logger.info('Client disconnected, aborting Gemini request');
+        abortController.abort();
+      }
+    });
+    
+    // 发送请求到 Gemini
+    const geminiResponse = await sendGeminiRequest({
+      messages,
+      model,
+      temperature,
+      maxTokens: max_tokens,
+      stream,
+      accessToken: account.accessToken,
+      proxy: account.proxy,
+      apiKeyId: apiKeyData.id,
+      signal: abortController.signal,
+      projectId: account.projectId
+    });
+    
+    if (stream) {
+      // 设置流式响应头
+      res.setHeader('Content-Type', 'text/event-stream');
+      res.setHeader('Cache-Control', 'no-cache');
+      res.setHeader('Connection', 'keep-alive');
+      res.setHeader('X-Accel-Buffering', 'no');
+      
+      // 流式传输响应
+      for await (const chunk of geminiResponse) {
+        if (abortController.signal.aborted) {
+          break;
+        }
+        res.write(chunk);
+      }
+      
+      res.end();
+    } else {
+      // 非流式响应
+      res.json(geminiResponse);
+    }
+    
+    const duration = Date.now() - startTime;
+    logger.info(`Gemini request completed in ${duration}ms`);
+    
+  } catch (error) {
+    logger.error('Gemini request error:', error);
+    
+    // 处理速率限制
+    if (error.status === 429) {
+      if (req.apiKeyData && req.account) {
+        await geminiAccountService.setAccountRateLimited(req.account.id, true);
+      }
+    }
+    
+    // 返回错误响应
+    const status = error.status || 500;
+    const errorResponse = {
+      error: error.error || {
+        message: error.message || 'Internal server error',
+        type: 'api_error'
+      }
+    };
+    
+    res.status(status).json(errorResponse);
+  } finally {
+    // 清理资源
+    if (abortController) {
+      abortController = null;
+    }
+  }
+});
+
+// 获取可用模型列表
+router.get('/models', authenticateApiKey, async (req, res) => {
+  try {
+    const apiKeyData = req.apiKeyData;
+    
+    // 检查权限
+    if (!checkPermissions(apiKeyData, 'gemini')) {
+      return res.status(403).json({
+        error: {
+          message: 'This API key does not have permission to access Gemini',
+          type: 'permission_denied'
+        }
+      });
+    }
+    
+    // 选择账户获取模型列表
+    const account = await geminiAccountService.selectAvailableAccount(apiKeyData.id);
+    
+    if (!account) {
+      // 返回默认模型列表
+      return res.json({
+        object: 'list',
+        data: [
+          {
+            id: 'gemini-2.0-flash-exp',
+            object: 'model',
+            created: Date.now() / 1000,
+            owned_by: 'google'
+          }
+        ]
+      });
+    }
+    
+    // 获取模型列表
+    const models = await getAvailableModels(account.accessToken, account.proxy);
+    
+    res.json({
+      object: 'list',
+      data: models
+    });
+    
+  } catch (error) {
+    logger.error('Failed to get Gemini models:', error);
+    res.status(500).json({
+      error: {
+        message: 'Failed to retrieve models',
+        type: 'api_error'
+      }
+    });
+  }
+});
+
+// 使用情况统计（与 Claude 共用）
+router.get('/usage', authenticateApiKey, async (req, res) => {
+  try {
+    const usage = req.apiKeyData.usage;
+    
+    res.json({
+      object: 'usage',
+      total_tokens: usage.total.tokens,
+      total_requests: usage.total.requests,
+      daily_tokens: usage.daily.tokens,
+      daily_requests: usage.daily.requests,
+      monthly_tokens: usage.monthly.tokens,
+      monthly_requests: usage.monthly.requests
+    });
+  } catch (error) {
+    logger.error('Failed to get usage stats:', error);
+    res.status(500).json({
+      error: {
+        message: 'Failed to retrieve usage statistics',
+        type: 'api_error'
+      }
+    });
+  }
+});
+
+// API Key 信息（与 Claude 共用）
+router.get('/key-info', authenticateApiKey, async (req, res) => {
+  try {
+    const keyData = req.apiKeyData;
+    
+    res.json({
+      id: keyData.id,
+      name: keyData.name,
+      permissions: keyData.permissions || 'all',
+      token_limit: keyData.tokenLimit,
+      tokens_used: keyData.usage.total.tokens,
+      tokens_remaining: keyData.tokenLimit > 0 
+        ? Math.max(0, keyData.tokenLimit - keyData.usage.total.tokens)
+        : null,
+      rate_limit: {
+        window: keyData.rateLimitWindow,
+        requests: keyData.rateLimitRequests
+      },
+      concurrency_limit: keyData.concurrencyLimit,
+      model_restrictions: {
+        enabled: keyData.enableModelRestriction,
+        models: keyData.restrictedModels
+      }
+    });
+  } catch (error) {
+    logger.error('Failed to get key info:', error);
+    res.status(500).json({
+      error: {
+        message: 'Failed to retrieve API key information',
+        type: 'api_error'
+      }
+    });
+  }
+});
+
+module.exports = router;