fix: types

src/utils/aspectRatioUtils.ts

@@ -1,5 +1,12 @@
-export type AspectRatio = '16:9' | '9:16' | '1:1' | '4:3' | '4:5' | '16:10' | '10:16';
+export const ASPECT_RATIOS = ['16:9', '9:16', '1:1', '4:3', '4:5', '16:10', '10:16'] as const;
 
+export type AspectRatio = typeof ASPECT_RATIOS[number];
+
+/**
+ * Returns the numeric value of an aspect ratio.
+ * Uses exhaustive type checking to ensure all AspectRatio cases are handled.
+ * If TypeScript errors here, a new ratio was added to the type but not handled.
+ */
 export function getAspectRatioValue(aspectRatio: AspectRatio): number {
   switch (aspectRatio) {
     case '16:9': return 16 / 9;
@@ -9,7 +16,11 @@ export function getAspectRatioValue(aspectRatio: AspectRatio): number {
     case '4:5':  return 4 / 5;
     case '16:10': return 16 / 10;
     case '10:16': return 10 / 16;
-    default: return 1;
+    default: {
+      // Ensures all cases are handled - TypeScript errors if missing
+      const _exhaustiveCheck: never = aspectRatio;
+      return _exhaustiveCheck;
+    }
   }
 }