fix(antigravity): implement automatic project ID discovery and prevent overwrite

This commit introduces automatic Cloud Code project discovery for the Antigravity provider. It ports the onboarding logic from gemini-core.js, handles missing credentials by triggering the auth flow, and ensures the discovered Project ID is correctly passed to the request payload builder, fixing the 403 Permission Denied error caused by random ID generation.

src/gemini/antigravity-core.js

@@ -91,29 +91,29 @@ function generateProjectID() {
 /**
  * 将 Gemini 格式请求转换为 Antigravity 格式
  */
-function geminiToAntigravity(modelName, payload) {
+function geminiToAntigravity(modelName, payload, projectId) {
     // 深拷贝请求体,避免修改原始对象
     let template = JSON.parse(JSON.stringify(payload));
-    
+
     // 设置基本字段
     template.model = modelName;
     template.userAgent = 'antigravity';
-    template.project = generateProjectID();
+    template.project = projectId || generateProjectID();
     template.requestId = generateRequestID();
-    
+
     // 确保 request 对象存在
     if (!template.request) {
         template.request = {};
     }
-    
+
     // 设置会话ID
     template.request.sessionId = generateSessionID();
-    
+
     // 删除安全设置
     if (template.request.safetySettings) {
         delete template.request.safetySettings;
     }
-    
+
     // 设置工具配置
     if (template.request.toolConfig) {
         if (!template.request.toolConfig.functionCallingConfig) {
@@ -121,12 +121,12 @@ function geminiToAntigravity(modelName, payload) {
         }
         template.request.toolConfig.functionCallingConfig.mode = 'VALIDATED';
     }
-    
+
     // 删除 maxOutputTokens
     if (template.request.generationConfig && template.request.generationConfig.maxOutputTokens) {
         delete template.request.generationConfig.maxOutputTokens;
     }
-    
+
     // 处理 Thinking 配置
     if (!modelName.startsWith('gemini-3-')) {
         if (template.request.generationConfig &&
@@ -136,7 +136,7 @@ function geminiToAntigravity(modelName, payload) {
             template.request.generationConfig.thinkingConfig.thinkingBudget = -1;
         }
     }
-    
+
     // 处理 Claude Sonnet 模型的工具声明
     if (modelName.startsWith('claude-sonnet-')) {
         if (template.request.tools && Array.isArray(template.request.tools)) {
@@ -153,7 +153,7 @@ function geminiToAntigravity(modelName, payload) {
             });
         }
     }
-    
+
     return template;
 }
 
@@ -162,23 +162,23 @@ function geminiToAntigravity(modelName, payload) {
  */
 function toGeminiApiResponse(antigravityResponse) {
     if (!antigravityResponse) return null;
-    
+
     const compliantResponse = {
         candidates: antigravityResponse.candidates
     };
-    
+
     if (antigravityResponse.usageMetadata) {
         compliantResponse.usageMetadata = antigravityResponse.usageMetadata;
     }
-    
+
     if (antigravityResponse.promptFeedback) {
         compliantResponse.promptFeedback = antigravityResponse.promptFeedback;
     }
-    
+
     if (antigravityResponse.automaticFunctionCallingHistory) {
         compliantResponse.automaticFunctionCallingHistory = antigravityResponse.automaticFunctionCallingHistory;
     }
-    
+
     return compliantResponse;
 }
 
@@ -187,16 +187,16 @@ function toGeminiApiResponse(antigravityResponse) {
  */
 function ensureRolesInContents(requestBody) {
     delete requestBody.model;
-    
+
     if (requestBody.system_instruction) {
         requestBody.systemInstruction = requestBody.system_instruction;
         delete requestBody.system_instruction;
     }
-    
+
     if (requestBody.systemInstruction && !requestBody.systemInstruction.role) {
         requestBody.systemInstruction.role = 'user';
     }
-    
+
     if (requestBody.contents && Array.isArray(requestBody.contents)) {
         requestBody.contents.forEach(content => {
             if (!content.role) {
@@ -204,7 +204,7 @@ function ensureRolesInContents(requestBody) {
             }
         });
     }
-    
+
     return requestBody;
 }
 
@@ -213,14 +213,14 @@ export class AntigravityApiService {
         this.authClient = new OAuth2Client(OAUTH_CLIENT_ID, OAUTH_CLIENT_SECRET);
         this.availableModels = [];
         this.isInitialized = false;
-        
+
         this.config = config;
         this.host = config.HOST;
         this.oauthCredsFilePath = config.ANTIGRAVITY_OAUTH_CREDS_FILE_PATH;
         this.baseURL = ANTIGRAVITY_BASE_URL_DAILY; // 使用通用 GEMINI_BASE_URL 配置
         this.userAgent = DEFAULT_USER_AGENT; // 支持通用 USER_AGENT 配置
         this.projectId = config.PROJECT_ID;
-        
+
         // 多环境降级顺序
         this.baseURLs = this.baseURL ? [this.baseURL] : [
             ANTIGRAVITY_BASE_URL_DAILY,
@@ -228,44 +228,42 @@ export class AntigravityApiService {
             // ANTIGRAVITY_BASE_URL_PROD // 生产环境已注释
         ];
     }
-    
+
     async initialize() {
         if (this.isInitialized) return;
         console.log('[Antigravity] Initializing Antigravity API Service...');
         await this.initializeAuth();
-        
+
         if (!this.projectId) {
-            this.projectId = generateProjectID();
+            this.projectId = await this.discoverProjectAndModels();
-            console.log(`[Antigravity] Generated Project ID: ${this.projectId}`);
         } else {
             console.log(`[Antigravity] Using provided Project ID: ${this.projectId}`);
+            // 获取可用模型
+            await this.fetchAvailableModels();
         }
-        
+
-        // 获取可用模型
-        await this.fetchAvailableModels();
-        
         this.isInitialized = true;
         console.log(`[Antigravity] Initialization complete. Project ID: ${this.projectId}`);
     }
-    
+
     async initializeAuth(forceRefresh = false) {
         // 检查是否需要刷新 Token
         const needsRefresh = forceRefresh || this.isTokenExpiringSoon();
-        
+
         if (this.authClient.credentials.access_token && !needsRefresh) {
             // Token 有效且不需要刷新
             return;
         }
-        
+
         // Antigravity 不支持 base64 配置，直接使用文件路径
-        
+
         const credPath = this.oauthCredsFilePath || path.join(os.homedir(), CREDENTIALS_DIR, CREDENTIALS_FILE);
         try {
             const data = await fs.readFile(credPath, "utf8");
             const credentials = JSON.parse(data);
             this.authClient.setCredentials(credentials);
             console.log('[Antigravity Auth] Authentication configured successfully from file.');
-            
+
             if (needsRefresh) {
                 console.log('[Antigravity Auth] Token expiring soon or force refresh requested. Refreshing token...');
                 const { credentials: newCredentials } = await this.authClient.refreshAccessToken();
@@ -287,7 +285,7 @@ export class AntigravityApiService {
             }
         }
     }
-    
+
     async getNewToken(credPath) {
         let host = this.host;
         if (!host || host === 'undefined') {
@@ -295,21 +293,21 @@ export class AntigravityApiService {
         }
         const redirectUri = `http://${host}:${AUTH_REDIRECT_PORT}`;
         this.authClient.redirectUri = redirectUri;
-        
+
         return new Promise(async (resolve, reject) => {
             const authUrl = this.authClient.generateAuthUrl({
                 access_type: 'offline',
                 scope: ['https://www.googleapis.com/auth/cloud-platform']
             });
-            
+
             console.log('\n[Antigravity Auth] 正在自动打开浏览器进行授权...');
             console.log('[Antigravity Auth] 授权链接:', authUrl, '\n');
-            
+
             // 自动打开浏览器
             const showFallbackMessage = () => {
                 console.log('[Antigravity Auth] 无法自动打开浏览器，请手动复制上面的链接到浏览器中打开');
             };
-            
+
             if (this.config) {
                 try {
                     const childProcess = await open(authUrl);
@@ -322,19 +320,19 @@ export class AntigravityApiService {
             } else {
                 showFallbackMessage();
             }
-            
+
             const server = http.createServer(async (req, res) => {
                 try {
                     const url = new URL(req.url, redirectUri);
                     const code = url.searchParams.get('code');
                     const errorParam = url.searchParams.get('error');
-                    
+
                     if (code) {
                         console.log(`[Antigravity Auth] Received successful callback from Google: ${req.url}`);
                         res.writeHead(200, { 'Content-Type': 'text/plain' });
                         res.end('Authentication successful! You can close this browser tab.');
                         server.close();
-                        
+
                         const { tokens } = await this.authClient.getToken(code);
                         await fs.mkdir(path.dirname(credPath), { recursive: true });
                         await fs.writeFile(credPath, JSON.stringify(tokens, null, 2));
@@ -356,7 +354,7 @@ export class AntigravityApiService {
                     reject(e);
                 }
             });
-            
+
             server.on('error', (err) => {
                 if (err.code === 'EADDRINUSE') {
                     const errorMessage = `[Antigravity Auth] Port ${AUTH_REDIRECT_PORT} on ${host} is already in use.`;
@@ -366,11 +364,11 @@ export class AntigravityApiService {
                     reject(err);
                 }
             });
-            
+
             server.listen(AUTH_REDIRECT_PORT, host);
         });
     }
-    
+
     isTokenExpiringSoon() {
         if (!this.authClient.credentials.expiry_date) {
             return true;
@@ -380,10 +378,85 @@ export class AntigravityApiService {
         const refreshSkewMs = REFRESH_SKEW * 1000;
         return expiryTime <= (currentTime + refreshSkewMs);
     }
-    
+
+    async discoverProjectAndModels() {
+        if (this.projectId) {
+            console.log(`[Antigravity] Using pre-configured Project ID: ${this.projectId}`);
+            return this.projectId;
+        }
+
+        console.log('[Antigravity] Discovering Project ID...');
+        try {
+            const initialProjectId = "";
+            // Prepare client metadata
+            const clientMetadata = {
+                ideType: "IDE_UNSPECIFIED",
+                platform: "PLATFORM_UNSPECIFIED",
+                pluginType: "GEMINI",
+                duetProject: initialProjectId,
+            };
+
+            // Call loadCodeAssist to discover the actual project ID
+            const loadRequest = {
+                cloudaicompanionProject: initialProjectId,
+                metadata: clientMetadata,
+            };
+
+            const loadResponse = await this.callApi('loadCodeAssist', loadRequest);
+
+            // Check if we already have a project ID from the response
+            if (loadResponse.cloudaicompanionProject) {
+                console.log(`[Antigravity] Discovered existing Project ID: ${loadResponse.cloudaicompanionProject}`);
+                // 获取可用模型
+                await this.fetchAvailableModels();
+                return loadResponse.cloudaicompanionProject;
+            }
+
+            // If no existing project, we need to onboard
+            const defaultTier = loadResponse.allowedTiers?.find(tier => tier.isDefault);
+            const tierId = defaultTier?.id || 'free-tier';
+
+            const onboardRequest = {
+                tierId: tierId,
+                cloudaicompanionProject: initialProjectId,
+                metadata: clientMetadata,
+            };
+
+            let lroResponse = await this.callApi('onboardUser', onboardRequest);
+
+            // Poll until operation is complete with timeout protection
+            const MAX_RETRIES = 30; // Maximum number of retries (60 seconds total)
+            let retryCount = 0;
+
+            while (!lroResponse.done && retryCount < MAX_RETRIES) {
+                await new Promise(resolve => setTimeout(resolve, 2000));
+                lroResponse = await this.callApi('onboardUser', onboardRequest);
+                retryCount++;
+            }
+
+            if (!lroResponse.done) {
+                throw new Error('Onboarding timeout: Operation did not complete within expected time.');
+            }
+
+            const discoveredProjectId = lroResponse.response?.cloudaicompanionProject?.id || initialProjectId;
+            console.log(`[Antigravity] Onboarded and discovered Project ID: ${discoveredProjectId}`);
+            // 获取可用模型
+            await this.fetchAvailableModels();
+            return discoveredProjectId;
+        } catch (error) {
+            console.error('[Antigravity] Failed to discover Project ID:', error.response?.data || error.message);
+            console.log('[Antigravity] Falling back to generated Project ID as last resort...');
+            const fallbackProjectId = generateProjectID();
+            console.log(`[Antigravity] Generated fallback Project ID: ${fallbackProjectId}`);
+            // 获取可用模型
+            await this.fetchAvailableModels();
+            return fallbackProjectId;
+        }
+    }
+
     async fetchAvailableModels() {
         console.log('[Antigravity] Fetching available models...');
-        
+
         for (const baseURL of this.baseURLs) {
             try {
                 const modelsURL = `${baseURL}/${ANTIGRAVITY_API_VERSION}:fetchAvailableModels`;
@@ -397,15 +470,15 @@ export class AntigravityApiService {
                     responseType: 'json',
                     body: JSON.stringify({})
                 };
-                
+
                 const res = await this.authClient.request(requestOptions);
-                
+
                 if (res.data && res.data.models) {
                     const models = Object.keys(res.data.models);
                     this.availableModels = models
                         .map(modelName2Alias)
                         .filter(alias => alias !== '');
-                    
+
                     console.log(`[Antigravity] Available models: [${this.availableModels.join(', ')}]`);
                     return;
                 }
@@ -413,20 +486,20 @@ export class AntigravityApiService {
                 console.error(`[Antigravity] Failed to fetch models from ${baseURL}:`, error.message);
             }
         }
-        
+
         console.warn('[Antigravity] Failed to fetch models from all endpoints. Using default models.');
         this.availableModels = ANTIGRAVITY_MODELS;
     }
-    
+
     async listModels() {
         if (!this.isInitialized) await this.initialize();
-        
+
         const now = Math.floor(Date.now() / 1000);
         const formattedModels = this.availableModels.map(modelId => {
-            const displayName = modelId.split('-').map(word => 
+            const displayName = modelId.split('-').map(word =>
                 word.charAt(0).toUpperCase() + word.slice(1)
             ).join(' ');
-            
+
             const modelInfo = {
                 name: `models/${modelId}`,
                 version: '1.0.0',
@@ -440,7 +513,7 @@ export class AntigravityApiService {
                 ownedBy: 'antigravity',
                 type: 'antigravity'
             };
-            
+
             if (modelId.endsWith('-thinking') || modelId.includes('-thinking-')) {
                 modelInfo.thinking = {
                     min: 1024,
@@ -449,23 +522,23 @@ export class AntigravityApiService {
                     dynamicAllowed: true
                 };
             }
-            
+
             return modelInfo;
         });
-        
+
         return { models: formattedModels };
     }
-    
+
     async callApi(method, body, isRetry = false, retryCount = 0, baseURLIndex = 0) {
         const maxRetries = this.config.REQUEST_MAX_RETRIES || 3;
         const baseDelay = this.config.REQUEST_BASE_DELAY || 1000;
-        
+
         if (baseURLIndex >= this.baseURLs.length) {
             throw new Error('All Antigravity base URLs failed');
         }
-        
+
         const baseURL = this.baseURLs[baseURLIndex];
-        
+
         try {
             const requestOptions = {
                 url: `${baseURL}/${ANTIGRAVITY_API_VERSION}:${method}`,
@@ -477,18 +550,18 @@ export class AntigravityApiService {
                 responseType: 'json',
                 body: JSON.stringify(body)
             };
-            
+
             const res = await this.authClient.request(requestOptions);
             return res.data;
         } catch (error) {
             console.error(`[Antigravity API] Error calling ${method} on ${baseURL}:`, error.response?.status, error.message);
-            
+
             if ((error.response?.status === 400 || error.response?.status === 401) && !isRetry) {
                 console.log('[Antigravity API] Received 401/400. Refreshing auth and retrying...');
                 await this.initializeAuth(true);
                 return this.callApi(method, body, true, retryCount, baseURLIndex);
             }
-            
+
             if (error.response?.status === 429) {
                 if (baseURLIndex + 1 < this.baseURLs.length) {
                     console.log(`[Antigravity API] Rate limited on ${baseURL}. Trying next base URL...`);
@@ -500,33 +573,33 @@ export class AntigravityApiService {
                     return this.callApi(method, body, isRetry, retryCount + 1, 0);
                 }
             }
-            
+
             if (!error.response && baseURLIndex + 1 < this.baseURLs.length) {
                 console.log(`[Antigravity API] Network error on ${baseURL}. Trying next base URL...`);
                 return this.callApi(method, body, isRetry, retryCount, baseURLIndex + 1);
             }
-            
+
             if (error.response?.status >= 500 && error.response?.status < 600 && retryCount < maxRetries) {
                 const delay = baseDelay * Math.pow(2, retryCount);
                 console.log(`[Antigravity API] Server error ${error.response.status}. Retrying in ${delay}ms...`);
                 await new Promise(resolve => setTimeout(resolve, delay));
                 return this.callApi(method, body, isRetry, retryCount + 1, baseURLIndex);
             }
-            
+
             throw error;
         }
     }
-    
+
     async * streamApi(method, body, isRetry = false, retryCount = 0, baseURLIndex = 0) {
         const maxRetries = this.config.REQUEST_MAX_RETRIES || 3;
         const baseDelay = this.config.REQUEST_BASE_DELAY || 1000;
-        
+
         if (baseURLIndex >= this.baseURLs.length) {
             throw new Error('All Antigravity base URLs failed');
         }
-        
+
         const baseURL = this.baseURLs[baseURLIndex];
-        
+
         try {
             const requestOptions = {
                 url: `${baseURL}/${ANTIGRAVITY_API_VERSION}:${method}`,
@@ -540,9 +613,9 @@ export class AntigravityApiService {
                 responseType: 'stream',
                 body: JSON.stringify(body)
             };
-            
+
             const res = await this.authClient.request(requestOptions);
-            
+
             if (res.status !== 200) {
                 let errorBody = '';
                 for await (const chunk of res.data) {
@@ -550,18 +623,18 @@ export class AntigravityApiService {
                 }
                 throw new Error(`Upstream API Error (Status ${res.status}): ${errorBody}`);
             }
-            
+
             yield* this.parseSSEStream(res.data);
         } catch (error) {
             console.error(`[Antigravity API] Error during stream ${method} on ${baseURL}:`, error.response?.status, error.message);
-            
+
             if ((error.response?.status === 400 || error.response?.status === 401) && !isRetry) {
                 console.log('[Antigravity API] Received 401/400 during stream. Refreshing auth and retrying...');
                 await this.initializeAuth(true);
                 yield* this.streamApi(method, body, true, retryCount, baseURLIndex);
                 return;
             }
-            
+
             if (error.response?.status === 429) {
                 if (baseURLIndex + 1 < this.baseURLs.length) {
                     console.log(`[Antigravity API] Rate limited on ${baseURL}. Trying next base URL...`);
@@ -575,13 +648,13 @@ export class AntigravityApiService {
                     return;
                 }
             }
-            
+
             if (!error.response && baseURLIndex + 1 < this.baseURLs.length) {
                 console.log(`[Antigravity API] Network error on ${baseURL}. Trying next base URL...`);
                 yield* this.streamApi(method, body, isRetry, retryCount, baseURLIndex + 1);
                 return;
             }
-            
+
             if (error.response?.status >= 500 && error.response?.status < 600 && retryCount < maxRetries) {
                 const delay = baseDelay * Math.pow(2, retryCount);
                 console.log(`[Antigravity API] Server error ${error.response.status} during stream. Retrying in ${delay}ms...`);
@@ -589,17 +662,17 @@ export class AntigravityApiService {
                 yield* this.streamApi(method, body, isRetry, retryCount + 1, baseURLIndex);
                 return;
             }
-            
+
             throw error;
         }
     }
-    
+
     async * parseSSEStream(stream) {
         const rl = readline.createInterface({
             input: stream,
             crlfDelay: Infinity
         });
-        
+
         let buffer = [];
         for await (const line of rl) {
             if (line.startsWith('data: ')) {
@@ -613,7 +686,7 @@ export class AntigravityApiService {
                 buffer = [];
             }
         }
-        
+
         if (buffer.length > 0) {
             try {
                 yield JSON.parse(buffer.join('\n'));
@@ -622,55 +695,55 @@ export class AntigravityApiService {
             }
         }
     }
-    
+
     async generateContent(model, requestBody) {
         console.log(`[Antigravity Auth Token] Time until expiry: ${formatExpiryTime(this.authClient.credentials.expiry_date)}`);
-        
+
         let selectedModel = model;
         if (!this.availableModels.includes(model)) {
             console.warn(`[Antigravity] Model '${model}' not found. Using default model: '${this.availableModels[0]}'`);
             selectedModel = this.availableModels[0];
         }
-        
+
         // 深拷贝请求体
         const processedRequestBody = ensureRolesInContents(JSON.parse(JSON.stringify(requestBody)));
         const actualModelName = alias2ModelName(selectedModel);
-        
+
         // 将处理后的请求体转换为 Antigravity 格式
-        const payload = geminiToAntigravity(actualModelName, { request: processedRequestBody });
+        const payload = geminiToAntigravity(actualModelName, { request: processedRequestBody }, this.projectId);
-        
+
         // 设置模型名称为实际模型名
         payload.model = actualModelName;
-        
+
         const response = await this.callApi('generateContent', payload);
         return toGeminiApiResponse(response.response);
     }
-    
+
     async * generateContentStream(model, requestBody) {
         console.log(`[Antigravity Auth Token] Time until expiry: ${formatExpiryTime(this.authClient.credentials.expiry_date)}`);
-        
+
         let selectedModel = model;
         if (!this.availableModels.includes(model)) {
             console.warn(`[Antigravity] Model '${model}' not found. Using default model: '${this.availableModels[0]}'`);
             selectedModel = this.availableModels[0];
         }
-        
+
         // 深拷贝请求体
         const processedRequestBody = ensureRolesInContents(JSON.parse(JSON.stringify(requestBody)));
         const actualModelName = alias2ModelName(selectedModel);
-        
+
         // 将处理后的请求体转换为 Antigravity 格式
-        const payload = geminiToAntigravity(actualModelName, { request: processedRequestBody });
+        const payload = geminiToAntigravity(actualModelName, { request: processedRequestBody }, this.projectId);
-        
+
         // 设置模型名称为实际模型名
         payload.model = actualModelName;
-        
+
         const stream = this.streamApi('streamGenerateContent', payload);
         for await (const chunk of stream) {
             yield toGeminiApiResponse(chunk.response);
         }
     }
-    
+
     isExpiryDateNear() {
         try {
             const currentTime = Date.now();