feat(billing): implement G1 AI credits overage flow with billing telemetry (#18590)

packages/core/src/config/config.ts

@@ -13,6 +13,7 @@ import type {
   ContentGenerator,
   ContentGeneratorConfig,
 } from '../core/contentGenerator.js';
+import type { OverageStrategy } from '../billing/billing.js';
 import {
   AuthType,
   createContentGenerator,
@@ -116,6 +117,7 @@ import {
 import { HookSystem } from '../hooks/index.js';
 import type {
   UserTierId,
+  GeminiUserTier,
   RetrieveUserQuotaResponse,
   AdminControlsSettings,
 } from '../code_assist/types.js';
@@ -573,6 +575,9 @@ export interface ConfigParameters {
     agents?: AgentSettings;
   }>;
   enableConseca?: boolean;
+  billing?: {
+    overageStrategy?: OverageStrategy;
+  };
 }
 
 export class Config {
@@ -754,6 +759,10 @@ export class Config {
       }>)
     | undefined;
 
+  private readonly billing: {
+    overageStrategy: OverageStrategy;
+  };
+
   private readonly enableAgents: boolean;
   private agents: AgentSettings;
   private readonly enableEventDrivenScheduler: boolean;
@@ -1001,6 +1010,10 @@ export class Config {
     this.onModelChange = params.onModelChange;
     this.onReload = params.onReload;
 
+    this.billing = {
+      overageStrategy: params.billing?.overageStrategy ?? 'ask',
+    };
+
     if (params.contextFileName) {
       setGeminiMdFilename(params.contextFileName);
     }
@@ -1264,6 +1277,10 @@ export class Config {
     return this.contentGenerator?.userTierName;
   }
 
+  getUserPaidTier(): GeminiUserTier | undefined {
+    return this.contentGenerator?.paidTier;
+  }
+
   /**
    * Provides access to the BaseLlmClient for stateless LLM operations.
    */
@@ -1578,6 +1595,19 @@ export class Config {
     this.hasAccessToPreviewModel = hasAccess;
   }
 
+  async refreshAvailableCredits(): Promise<void> {
+    const codeAssistServer = getCodeAssistServer(this);
+    if (!codeAssistServer) {
+      return;
+    }
+    try {
+      await codeAssistServer.refreshAvailableCredits();
+    } catch {
+      // Non-fatal: proceed even if refresh fails.
+      // The actual credit balance will be verified server-side.
+    }
+  }
+
   async refreshUserQuota(): Promise<RetrieveUserQuotaResponse | undefined> {
     const codeAssistServer = getCodeAssistServer(this);
     if (!codeAssistServer || !codeAssistServer.projectId) {
@@ -2052,6 +2082,19 @@ export class Config {
     return this.telemetrySettings.outfile;
   }
 
+  getBillingSettings(): { overageStrategy: OverageStrategy } {
+    return this.billing;
+  }
+
+  /**
+   * Updates the overage strategy at runtime.
+   * Used to switch from 'ask' to 'always' after the user accepts credits
+   * via the overage dialog, so subsequent API calls auto-include credits.
+   */
+  setOverageStrategy(strategy: OverageStrategy): void {
+    this.billing.overageStrategy = strategy;
+  }
+
   getTelemetryUseCollector(): boolean {
     return this.telemetrySettings.useCollector ?? false;
   }