fix(core): fix quota footer for non-auto models and improve display (#25121)

packages/core/src/config/config.test.ts

@@ -3006,6 +3006,78 @@ describe('Config Quota & Preview Model Access', () => {
       // Never set => stays null (unknown); getter returns true so UI shows preview
       expect(config.getHasAccessToPreviewModel()).toBe(true);
     });
+    it('should derive quota from remainingFraction when remainingAmount is missing', async () => {
+      mockCodeAssistServer.retrieveUserQuota.mockResolvedValue({
+        buckets: [
+          {
+            modelId: 'gemini-3-flash-preview',
+            remainingFraction: 0.96,
+          },
+        ],
+      });
+
+      config.setModel('gemini-3-flash-preview');
+      mockCoreEvents.emitQuotaChanged.mockClear();
+      await config.refreshUserQuota();
+
+      // Normalized: limit=100, remaining=96
+      expect(mockCoreEvents.emitQuotaChanged).toHaveBeenCalledWith(
+        96,
+        100,
+        undefined,
+      );
+      expect(config.getQuotaRemaining()).toBe(96);
+      expect(config.getQuotaLimit()).toBe(100);
+    });
+
+    it('should store quota from remainingFraction when remainingFraction is 0', async () => {
+      mockCodeAssistServer.retrieveUserQuota.mockResolvedValue({
+        buckets: [
+          {
+            modelId: 'gemini-3-pro-preview',
+            remainingFraction: 0,
+          },
+        ],
+      });
+
+      config.setModel('gemini-3-pro-preview');
+      mockCoreEvents.emitQuotaChanged.mockClear();
+      await config.refreshUserQuota();
+
+      // remaining=0, limit=100 but limit>0 check still passes
+      // however remaining=0 means 0% remaining = 100% used
+      expect(config.getQuotaRemaining()).toBe(0);
+      expect(config.getQuotaLimit()).toBe(100);
+    });
+
+    it('should emit QuotaChanged when model is switched via setModel', async () => {
+      mockCodeAssistServer.retrieveUserQuota.mockResolvedValue({
+        buckets: [
+          {
+            modelId: 'gemini-2.5-pro',
+            remainingAmount: '10',
+            remainingFraction: 0.2,
+          },
+          {
+            modelId: 'gemini-2.5-flash',
+            remainingAmount: '80',
+            remainingFraction: 0.8,
+          },
+        ],
+      });
+
+      config.setModel('auto-gemini-2.5');
+      await config.refreshUserQuota();
+      mockCoreEvents.emitQuotaChanged.mockClear();
+
+      // Switch to a specific model — should re-emit quota for that model
+      config.setModel('gemini-2.5-pro');
+      expect(mockCoreEvents.emitQuotaChanged).toHaveBeenCalledWith(
+        10,
+        50,
+        undefined,
+      );
+    });
   });
 
   describe('refreshUserQuotaIfStale', () => {

packages/core/src/config/config.ts

@@ -832,18 +832,16 @@ export class Config implements McpContext, AgentLoopContext {
   private lastEmittedQuotaLimit: number | undefined;
 
   private emitQuotaChangedEvent(): void {
-    const pooled = this.getPooledQuota();
+    const remaining = this.getQuotaRemaining();
+    const limit = this.getQuotaLimit();
+    const resetTime = this.getQuotaResetTime();
     if (
-      this.lastEmittedQuotaRemaining !== pooled.remaining ||
-      this.lastEmittedQuotaLimit !== pooled.limit
+      this.lastEmittedQuotaRemaining !== remaining ||
+      this.lastEmittedQuotaLimit !== limit
     ) {
-      this.lastEmittedQuotaRemaining = pooled.remaining;
-      this.lastEmittedQuotaLimit = pooled.limit;
-      coreEvents.emitQuotaChanged(
-        pooled.remaining,
-        pooled.limit,
-        pooled.resetTime,
-      );
+      this.lastEmittedQuotaRemaining = remaining;
+      this.lastEmittedQuotaLimit = limit;
+      coreEvents.emitQuotaChanged(remaining, limit, resetTime);
     }
   }
 
@@ -1819,6 +1817,9 @@ export class Config implements McpContext, AgentLoopContext {
       // When the user explicitly sets a model, that becomes the active model.
       this._activeModel = newModel;
       coreEvents.emitModelChanged(newModel);
+      this.lastEmittedQuotaRemaining = undefined;
+      this.lastEmittedQuotaLimit = undefined;
+      this.emitQuotaChangedEvent();
     }
     if (this.onModelChange && !isTemporary) {
       this.onModelChange(newModel);
@@ -2112,24 +2113,31 @@ export class Config implements McpContext, AgentLoopContext {
         this.lastQuotaFetchTime = Date.now();
 
         for (const bucket of quota.buckets) {
-          if (
-            bucket.modelId &&
-            bucket.remainingAmount &&
-            bucket.remainingFraction != null
-          ) {
-            const remaining = parseInt(bucket.remainingAmount, 10);
-            const limit =
+          if (!bucket.modelId || bucket.remainingFraction == null) {
+            continue;
+          }
+
+          let remaining: number;
+          let limit: number;
+
+          if (bucket.remainingAmount) {
+            remaining = parseInt(bucket.remainingAmount, 10);
+            limit =
               bucket.remainingFraction > 0
                 ? Math.round(remaining / bucket.remainingFraction)
                 : (this.modelQuotas.get(bucket.modelId)?.limit ?? 0);
+          } else {
+            // Server only sent remainingFraction — use a normalized scale.
+            limit = 100;
+            remaining = Math.round(bucket.remainingFraction * limit);
+          }
 
-            if (!isNaN(remaining) && Number.isFinite(limit) && limit > 0) {
-              this.modelQuotas.set(bucket.modelId, {
-                remaining,
-                limit,
-                resetTime: bucket.resetTime,
-              });
-            }
+          if (!isNaN(remaining) && Number.isFinite(limit) && limit > 0) {
+            this.modelQuotas.set(bucket.modelId, {
+              remaining,
+              limit,
+              resetTime: bucket.resetTime,
+            });
           }
         }
         this.emitQuotaChangedEvent();