feat: implement file existence check and improve file upload handling

src/lib/storage/storage.utils.ts

@@ -11,18 +11,36 @@ export const FileUploadResp = z.object({
 });
 export type FileUploadResp = z.infer<StorageProvider>;
 
+async function hashFile(file: File): Promise<string> {
+    const buffer = await file.arrayBuffer();
+    const hashBuffer = await crypto.subtle.digest('SHA-256', buffer);
+    const hex = Array.from(new Uint8Array(hashBuffer))
+        .map((b) => b.toString(16).padStart(2, '0'))
+        .join('');
+    const ext = file.name.split('.').pop();
+    return ext ? `${hex}.${ext}` : hex;
+}
+
 export const uploadFile = wrap(async (file: File) => {
-    const uniqueFileKey = crypto.randomUUID();
-    const result = await storage.getPutUrl(uniqueFileKey, file.type);
+    const fileKey = await hashFile(file);
+
+    const existsResult = await storage.checkExists(fileKey);
+    if (existsResult) {
+        const presignedUrl = await storage.getSignedUrl(fileKey);
+        if (!presignedUrl.ok) {
+            throw new Error('Failed to retrieve file URL');
+        }
+        return { signedUrl: presignedUrl.value, key: fileKey };
+    }
+
+    const result = await storage.getPutUrl(fileKey, file.type);
     if (!result.ok) {
         throw new Error('File upload failed');
     }
 
     const response = await fetch(result.value, {
         method: 'PUT',
-        headers: {
-            'Content-Type': file.type,
-        },
+        headers: { 'Content-Type': file.type },
         body: file,
     });
 
@@ -30,12 +48,9 @@ export const uploadFile = wrap(async (file: File) => {
         throw new Error('Failed to upload file');
     }
 
-    const presignedUrl = await storage.getSignedUrl(uniqueFileKey);
+    const presignedUrl = await storage.getSignedUrl(fileKey);
     if (!presignedUrl.ok) {
         throw new Error('Failed to retrieve file URL');
     }
-    return {
-        signedUrl: presignedUrl.value,
-        key: uniqueFileKey,
-    };
+    return { signedUrl: presignedUrl.value, key: fileKey };
 });