fix: address PR review comments for security, CSS, and test isolation

Security & API route fixes:
- Remove API key query param support in fal/models route to prevent credential leakage
- Fix MIME type fallback in save-generation route (now uses prefix-based fallback: image/* -> png, video/* -> mp4, unknown -> bin)
- Add timeout (60s) and size limits (500MB) for remote fetch in save-generation route using AbortController

CSS fix:
- Consolidate duplicate :root blocks in globals.css
- Change handle selector from data-handletype="prompt" to data-handletype="text"
- Update --handle-color-text CSS variable from #a3a3a3 to #3b82f6

Test file global mock isolation:
- Fix useAnnotationStore mock to support Zustand selector pattern
- Use vi.stubGlobal() instead of direct global assignments to prevent test leakage
- Restore global.Image in afterAll hook in AnnotationModal.test.tsx
- Wrap async Done assertion in waitFor() in AnnotationModal.test.tsx
- Use idiomatic fireEvent.dragOver() in AnnotationNode.test.tsx
- Fix global.confirm stub with proper beforeAll/afterAll lifecycle in CostDialog.test.tsx
- Import ReactNode type properly in EdgeToolbar.test.tsx
- Update save-generation route test to expect AbortController signal in fetch call

src/app/api/providers/fal/models/route.ts

@@ -98,17 +98,20 @@ type ModelsResponse = ModelsSuccessResponse | ModelsErrorResponse;
  * Fetches available models from fal.ai API.
  * API key is optional - fal.ai works without but with rate limits.
  *
+ * Headers:
+ *   - X-API-Key: API key for authentication (recommended)
+ *   - Authorization: Alternative auth header
+ *
  * Query params:
  *   - search: Optional search query to filter models
- *   - api_key: Alternative to X-API-Key header
  */
 export async function GET(
   request: NextRequest
 ): Promise<NextResponse<ModelsResponse>> {
-  // Get optional API key from header or query param
+  // Get optional API key from header only (never from query params to avoid credential leakage)
   const apiKey =
     request.headers.get("X-API-Key") ||
-    request.nextUrl.searchParams.get("api_key");
+    request.headers.get("Authorization")?.replace(/^Key\s+/i, "");
 
   const searchQuery = request.nextUrl.searchParams.get("search");
 

src/app/api/save-generation/__tests__/route.test.ts

@@ -264,7 +264,11 @@ describe("/api/save-generation route", () => {
 
       expect(data.success).toBe(true);
       expect(data.filename).toContain(expectedHash);
-      expect(global.fetch).toHaveBeenCalledWith("https://example.com/image.png");
+      // Fetch is called with URL and options object containing AbortController signal
+      expect(global.fetch).toHaveBeenCalledWith(
+        "https://example.com/image.png",
+        expect.objectContaining({ signal: expect.any(AbortSignal) })
+      );
     });
 
     it("should handle failed HTTP fetch", async () => {

src/app/api/save-generation/route.ts

@@ -11,11 +11,27 @@ function getExtensionFromMime(mimeType: string): string {
     "image/jpeg": "jpg",
     "image/gif": "gif",
     "image/webp": "webp",
+    "image/svg+xml": "svg",
     "video/mp4": "mp4",
     "video/webm": "webm",
     "video/quicktime": "mov",
   };
-  return mimeToExt[mimeType] || "mp4";
+
+  // Check explicit mapping first
+  if (mimeToExt[mimeType]) {
+    return mimeToExt[mimeType];
+  }
+
+  // Fallback based on MIME type prefix
+  if (mimeType.startsWith("image/")) {
+    return "png";
+  }
+  if (mimeType.startsWith("video/")) {
+    return "mp4";
+  }
+
+  // Unknown type - use generic binary extension
+  return "bin";
 }
 
 // Helper to detect if a string is an HTTP URL
@@ -106,16 +122,48 @@ export async function POST(request: NextRequest) {
       // Handle HTTP URL (common for large video files from providers)
       logger.info('file.save', 'Fetching content from URL', { url: content.substring(0, 100) });
 
-      const response = await fetch(content);
+      // Set up timeout to prevent hanging requests (60 seconds for large video files)
+      const FETCH_TIMEOUT_MS = 60000;
+      const MAX_CONTENT_SIZE = 500 * 1024 * 1024; // 500MB max
+
+      const controller = new AbortController();
+      const timeoutId = setTimeout(() => controller.abort(), FETCH_TIMEOUT_MS);
+
+      try {
+        const response = await fetch(content, { signal: controller.signal });
+        clearTimeout(timeoutId);
+
         if (!response.ok) {
           throw new Error(`Failed to fetch content: ${response.status} ${response.statusText}`);
         }
 
+        // Check content-length before downloading to avoid excessive bandwidth usage
+        const contentLength = response.headers.get("content-length");
+        if (contentLength) {
+          const size = parseInt(contentLength, 10);
+          if (size > MAX_CONTENT_SIZE) {
+            throw new Error(`Content size ${size} bytes exceeds maximum allowed ${MAX_CONTENT_SIZE} bytes`);
+          }
+        }
+
         const contentType = response.headers.get("content-type") || (isVideo ? "video/mp4" : "image/png");
         extension = getExtensionFromMime(contentType);
 
         const arrayBuffer = await response.arrayBuffer();
+
+        // Double-check actual size after download
+        if (arrayBuffer.byteLength > MAX_CONTENT_SIZE) {
+          throw new Error(`Downloaded content size ${arrayBuffer.byteLength} bytes exceeds maximum allowed ${MAX_CONTENT_SIZE} bytes`);
+        }
+
         buffer = Buffer.from(arrayBuffer);
+      } catch (fetchError) {
+        clearTimeout(timeoutId);
+        if (fetchError instanceof Error && fetchError.name === 'AbortError') {
+          throw new Error(`Fetch timed out after ${FETCH_TIMEOUT_MS}ms`);
+        }
+        throw fetchError;
+      }
     } else {
       // Handle base64 data URL
       const dataUrlMatch = content.match(/^data:([\w/+-]+);base64,/);

src/app/globals.css

@@ -7,6 +7,9 @@
 :root {
   --background: #0a0a0a;
   --foreground: #fafafa;
+  /* Handle colors (used by labels) */
+  --handle-color-image: #10b981;
+  --handle-color-text: #3b82f6;
 }
 
 html {
@@ -70,17 +73,11 @@ body {
   background: #10b981;
 }
 
-/* Prompt/text handles - soft blue */
-.react-flow__handle[data-handletype="prompt"] {
+/* Text handles - soft blue */
+.react-flow__handle[data-handletype="text"] {
   background: #3b82f6;
 }
 
-/* CSS variables for handle colors (used by labels) */
-:root {
-  --handle-color-image: #10b981;
-  --handle-color-text: #a3a3a3;
-}
-
 .react-flow__edge-path {
   stroke: #94a3b8;
   stroke-width: 3;

src/components/__tests__/AnnotationModal.test.tsx

@@ -1,12 +1,13 @@
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
-import { render, screen, fireEvent } from "@testing-library/react";
+import { describe, it, expect, vi, beforeEach, afterEach, beforeAll, afterAll } from "vitest";
+import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import type { ReactNode } from "react";
 import { AnnotationModal } from "@/components/AnnotationModal";
 import { ToolType, ToolOptions } from "@/types";
 
 // Mock Konva and react-konva - canvas internals cannot be tested in jsdom
 vi.mock("react-konva", () => ({
-  Stage: ({ children }: { children: React.ReactNode }) => <div data-testid="konva-stage">{children}</div>,
-  Layer: ({ children }: { children: React.ReactNode }) => <div data-testid="konva-layer">{children}</div>,
+  Stage: ({ children }: { children: ReactNode }) => <div data-testid="konva-stage">{children}</div>,
+  Layer: ({ children }: { children: ReactNode }) => <div data-testid="konva-layer">{children}</div>,
   Image: () => <div data-testid="konva-image" />,
   Rect: () => <div data-testid="konva-rect" />,
   Ellipse: () => <div data-testid="konva-ellipse" />,
@@ -74,7 +75,12 @@ const createMockAnnotationStore = (overrides = {}) => ({
 let mockAnnotationStore = createMockAnnotationStore();
 
 vi.mock("@/store/annotationStore", () => ({
-  useAnnotationStore: () => mockAnnotationStore,
+  useAnnotationStore: (selector?: (state: ReturnType<typeof createMockAnnotationStore>) => unknown) => {
+    if (selector) {
+      return selector(mockAnnotationStore);
+    }
+    return mockAnnotationStore;
+  },
 }));
 
 // Mock workflow store
@@ -104,12 +110,17 @@ class MockImage {
   }
 }
 
-Object.defineProperty(global, "Image", {
-  value: MockImage,
-  writable: true,
-});
+// Store original Image to restore later
+const OriginalImage = global.Image;
 
 describe("AnnotationModal", () => {
+  beforeAll(() => {
+    vi.stubGlobal("Image", MockImage);
+  });
+
+  afterAll(() => {
+    vi.stubGlobal("Image", OriginalImage);
+  });
   beforeEach(() => {
     vi.clearAllMocks();
     mockAnnotationStore = createMockAnnotationStore();
@@ -275,10 +286,12 @@ describe("AnnotationModal", () => {
       // so we just verify the button exists and triggers the handler
       fireEvent.click(screen.getByText("Done"));
 
-      // closeModal should be called after save
+      // closeModal should be called after save (async operation)
+      await waitFor(() => {
         expect(mockCloseModal).toHaveBeenCalled();
       });
     });
+  });
 
   describe("Color Picker", () => {
     it("should render color label", () => {

src/components/__tests__/AnnotationNode.test.tsx

@@ -1,5 +1,6 @@
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { describe, it, expect, vi, beforeEach, afterEach, beforeAll, afterAll } from "vitest";
 import { render, screen, fireEvent, waitFor } from "@testing-library/react";
+import type { ReactNode } from "react";
 import { AnnotationNode } from "@/components/nodes/AnnotationNode";
 import { ReactFlowProvider } from "@xyflow/react";
 import { AnnotationNodeData } from "@/types";
@@ -32,7 +33,6 @@ vi.mock("@/store/annotationStore", () => ({
 
 // Mock alert
 const mockAlert = vi.fn();
-global.alert = mockAlert;
 
 // Mock DataTransfer
 class MockDataTransfer {
@@ -50,14 +50,22 @@ class MockDataTransfer {
     };
   }
 }
-global.DataTransfer = MockDataTransfer as unknown as typeof DataTransfer;
 
 // Wrapper component for React Flow context
-function TestWrapper({ children }: { children: React.ReactNode }) {
+function TestWrapper({ children }: { children: ReactNode }) {
   return <ReactFlowProvider>{children}</ReactFlowProvider>;
 }
 
 describe("AnnotationNode", () => {
+  beforeAll(() => {
+    vi.stubGlobal("alert", mockAlert);
+    vi.stubGlobal("DataTransfer", MockDataTransfer);
+  });
+
+  afterAll(() => {
+    vi.unstubAllGlobals();
+  });
+
   beforeEach(() => {
     vi.clearAllMocks();
 
@@ -372,7 +380,7 @@ describe("AnnotationNode", () => {
     });
 
     it("should process valid image file and call updateNodeData", async () => {
-      // Mock FileReader
+      // Mock FileReader using vi.stubGlobal for proper cleanup
       const mockReadAsDataURL = vi.fn();
       class MockFileReader {
         onload: ((event: ProgressEvent<FileReader>) => void) | null = null;
@@ -384,7 +392,7 @@ describe("AnnotationNode", () => {
           }, 0);
         }
       }
-      global.FileReader = MockFileReader as unknown as typeof FileReader;
+      vi.stubGlobal("FileReader", MockFileReader);
 
       render(
         <TestWrapper>
@@ -405,6 +413,12 @@ describe("AnnotationNode", () => {
           annotations: [],
         });
       });
+
+      // Restore FileReader
+      vi.unstubAllGlobals();
+      // Re-stub the globals we need for other tests
+      vi.stubGlobal("alert", mockAlert);
+      vi.stubGlobal("DataTransfer", MockDataTransfer);
     });
 
     it("should reject non-image file types", () => {
@@ -452,13 +466,9 @@ describe("AnnotationNode", () => {
       );
 
       const dropZone = screen.getByText("Drop, click, or connect").parentElement!;
-      const dragOverEvent = new Event("dragover", { bubbles: true });
-      Object.assign(dragOverEvent, {
-        preventDefault: vi.fn(),
-        stopPropagation: vi.fn(),
-      });
 
-      fireEvent(dropZone, dragOverEvent);
+      // Use fireEvent.dragOver for idiomatic testing
+      fireEvent.dragOver(dropZone);
 
       // Should handle without error
       expect(dropZone).toBeInTheDocument();

src/components/__tests__/CostDialog.test.tsx

@@ -1,4 +1,4 @@
-import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import { describe, it, expect, vi, beforeEach, afterEach, beforeAll, afterAll } from "vitest";
 import { render, screen, fireEvent } from "@testing-library/react";
 import { CostDialog } from "@/components/CostDialog";
 import { PredictedCostResult } from "@/utils/costCalculator";
@@ -18,11 +18,19 @@ vi.mock("@/store/workflowStore", () => ({
 
 // Mock confirm
 const mockConfirm = vi.fn(() => true);
-global.confirm = mockConfirm;
 
 describe("CostDialog", () => {
+  beforeAll(() => {
+    vi.stubGlobal("confirm", mockConfirm);
+  });
+
+  afterAll(() => {
+    vi.unstubAllGlobals();
+  });
+
   beforeEach(() => {
     vi.clearAllMocks();
+    mockConfirm.mockReturnValue(true); // Reset default return value
     mockUseWorkflowStore.mockImplementation((selector) => {
       const state = {
         resetIncurredCost: mockResetIncurredCost,

src/components/__tests__/EdgeToolbar.test.tsx

@@ -1,5 +1,6 @@
 import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
 import { render, screen, fireEvent } from "@testing-library/react";
+import type { ReactNode } from "react";
 import { EdgeToolbar } from "@/components/EdgeToolbar";
 import { ReactFlowProvider } from "@xyflow/react";
 
@@ -18,7 +19,7 @@ vi.mock("@/store/workflowStore", () => ({
 }));
 
 // Wrapper component for React Flow context
-function TestWrapper({ children }: { children: React.ReactNode }) {
+function TestWrapper({ children }: { children: ReactNode }) {
   return <ReactFlowProvider>{children}</ReactFlowProvider>;
 }