fix: check type

src/files/NodeFilesHandler.ts

@@ -4,45 +4,56 @@ import { FormDataRequest } from 'types/API';
 
 export class NodeFilesHandler extends BaseFilesHandler {
   private async convertReadableStream(readableStream: ReadableStream): Promise<NodeJS.ReadableStream> {
-    const { Readable } = await import('stream');
-    const reader = readableStream.getReader();
+    try {
+      if (typeof window === 'undefined') {
+        const { Readable } = await import('stream');
+        const reader = readableStream.getReader();
 
-    return new Readable({
-      async read() {
-        const { done, value } = await reader.read();
-        if (done) {
-          this.push(null);
-        } else {
-          this.push(value);
-        }
-      },
-    });
+        return new Readable({
+          async read() {
+            const { done, value } = await reader.read();
+            if (done) {
+              this.push(null);
+            } else {
+              this.push(value);
+            }
+          },
+        });
+      } else {
+        throw new Error('Stream conversion is not supported in browser environment');
+      }
+    } catch (error) {
+      console.error('Error in convertReadableStream:', error);
+      throw error;
+    }
   }
 
   async prepareFormDataRequest(file: FilePathOrFileObject): Promise<FormDataRequest> {
     console.log('Preparing form data request for Node.js');
     try {
-      const FormData = await import('form-data').then((m) => m.default || m);
+      const FormData = await import('form-data').then(m => m.default || m);
       console.log('Successfully imported form-data module');
-
+      
       const formData = new FormData();
       console.log('Created new FormData instance');
 
       if (typeof file === 'string') {
-        const fs = await import('fs').then((m) => m.default || m);
-        if (!fs.existsSync(file)) {
-          throw new Error(`File not found: ${file}`);
+        if (typeof window === 'undefined') {
+          const fs = await import('fs').then(m => m.default || m);
+          if (!fs.existsSync(file)) {
+            throw new Error(`File not found: ${file}`);
+          }
+          console.log(`Appending file from path: ${file}`);
+          formData.append('file', fs.createReadStream(file), { filename: file.split('/').pop() });
+        } else {
+          throw new Error('File system operations are not supported in browser environment');
         }
-        console.log(`Appending file from path: ${file}`);
-        formData.append('file', fs.createReadStream(file), { filename: file.split('/').pop() });
       } else if (file && typeof file === 'object') {
         console.log('Processing file object:', file);
         if ('buffer' in file) {
-          // Handle Node.js file-like object
           console.log('Appending file from buffer');
           formData.append('file', file.buffer, { filename: file.name, contentType: file.type });
         } else if ('stream' in file && typeof file.stream === 'function') {
-          // Handle File object
           console.log('Converting and appending file from stream');
           const nodeStream = await this.convertReadableStream(file.stream());
           formData.append('file', nodeStream, { filename: file.name, contentType: file.type });