fix: set correct filename in openFile API, closes #803 (#810)

apps/readest-app/src/services/nativeAppService.ts

@@ -89,7 +89,7 @@ export const nativeFileSystem: FileSystem = {
         // Once the bug is resolved, we should switch back to using NativeFile.
         // RemoteFile is not usable on Android due to unknown issues of range fetch with Android WebView.
         const absolutePath = await join(prefix, path);
-        return await new RemoteFile(this.getURL(absolutePath), path).open();
+        return await new RemoteFile(this.getURL(absolutePath), fname).open();
       } else {
         return await new NativeFile(fp, fname, base ? baseDir : null).open();
       }

apps/readest-app/src/services/webAppService.ts

@@ -54,12 +54,12 @@ const indexedDBFileSystem: FileSystem = {
       return path;
     }
   },
-  async openFile(path: string, base: BaseDir) {
+  async openFile(path: string, base: BaseDir, filename?: string) {
     if (isValidURL(path)) {
-      return await new RemoteFile(path).open();
+      return await new RemoteFile(path, filename).open();
     } else {
       const content = await this.readFile(path, base, 'binary');
-      return new File([content], path);
+      return new File([content], filename || path);
     }
   },
   async copyFile(srcPath: string, dstPath: string, base: BaseDir) {