feat: P3c LLM集成层增强 (模型目录 + 用量统计 + getModelInfo)

backend/src/modules/ai/ai-gateway.service.ts

@@ -11,15 +11,32 @@ export interface ChatOptions {
   max_tokens?: number;
 }
 
+export interface ModelInfo {
+  id: string;
+  provider: string;
+  capabilities: string[];
+  contextWindow: number;
+}
+
 interface AIProvider {
   name: string;
   chat(messages: ChatMessage[], options?: ChatOptions): Promise<string>;
 }
 
+const MODEL_CATALOG: Record<string, ModelInfo> = {
+  'general': { id: 'general', provider: 'OpenAI 兼容', capabilities: ['chat', 'code'], contextWindow: 8192 },
+  'openai': { id: 'openai', provider: 'OpenAI 兼容', capabilities: ['chat', 'code'], contextWindow: 8192 },
+  'gpt-3.5': { id: 'gpt-3.5', provider: 'OpenAI', capabilities: ['chat', 'code'], contextWindow: 16384 },
+  'gpt-4': { id: 'gpt-4', provider: 'OpenAI', capabilities: ['chat', 'code', 'vision'], contextWindow: 32768 },
+  'opencode-go': { id: 'opencode-go', provider: 'OpenCode Go', capabilities: ['chat', 'code'], contextWindow: 32768 },
+  'deepseek-v4-flash': { id: 'deepseek-v4-flash', provider: 'OpenCode Go', capabilities: ['chat', 'code'], contextWindow: 32768 },
+}
+
 @Injectable()
 export class AIGatewayService {
   private readonly logger = new Logger(AIGatewayService.name);
   private providers: Map<string, AIProvider> = new Map();
+  private usageStats: Record<string, { total: number; success: number; failed: number }> = {};
 
   constructor() {
     this.registerProviders();
@@ -73,15 +90,20 @@ export class AIGatewayService {
     const providerKey = modelMap[model.toLowerCase()] || (model.includes('/') ? 'openai' : model);
     const provider = this.providers.get(providerKey);
 
+    if (!this.usageStats[providerKey]) this.usageStats[providerKey] = { total: 0, success: 0, failed: 0 };
+    this.usageStats[providerKey].total++;
+
     if (provider) {
       try {
         const reply = await provider.chat(messages, options);
         if (typeof reply !== 'string' || reply.length === 0) {
           throw new Error(`AI 返回内容为空: ${JSON.stringify(reply)}`);
         }
+        this.usageStats[providerKey].success++;
         return reply;
       } catch (err: any) {
         this.logger.error(`${provider.name} 调用失败: ${err.message}`);
+        this.usageStats[providerKey].failed++;
         return this.fallback(messages);
       }
     }
@@ -114,6 +136,15 @@ export class AIGatewayService {
     return `我是宇之然 AI 助手。关于"${lastMsg.slice(0, 50)}..."的问题，我已收到。当前 AI 沙箱处于模拟模式，请配置 API Key 以获取真实回复。已配置的 API：${names}。`;
   }
 
+  getModelInfo(model: string): ModelInfo {
+    const key = model.toLowerCase();
+    return MODEL_CATALOG[key] || { id: model, provider: '未知', capabilities: ['chat'], contextWindow: 4096 };
+  }
+
+  getUsageStats() {
+    return { ...this.usageStats };
+  }
+
   getRegisteredProviders(): string[] {
     return Array.from(this.providers.keys());
   }