Add visual workflow builder, fix critical bugs, and add Arabic i18n support

src/js/workflow/nodes/fb2-to-pdf-node.ts

@@ -0,0 +1,69 @@
+import { ClassicPreset } from 'rete';
+import { BaseWorkflowNode } from './base-node';
+import { pdfSocket } from '../sockets';
+import type { PDFData, SocketData, MultiPDFData } from '../types';
+import { PDFDocument } from 'pdf-lib';
+import { loadPyMuPDF } from '../../utils/pymupdf-loader.js';
+
+export class Fb2ToPdfNode extends BaseWorkflowNode {
+  readonly category = 'Input' as const;
+  readonly icon = 'ph-book-bookmark';
+  readonly description = 'Upload FB2 e-books and convert to PDF';
+
+  private files: File[] = [];
+
+  constructor() {
+    super('FB2 Input');
+    this.addOutput('pdf', new ClassicPreset.Output(pdfSocket, 'PDF'));
+  }
+
+  async addFiles(fileList: File[]): Promise<void> {
+    for (const file of fileList) {
+      if (file.name.toLowerCase().endsWith('.fb2')) {
+        this.files.push(file);
+      }
+    }
+  }
+
+  removeFile(index: number): void {
+    this.files.splice(index, 1);
+  }
+  hasFile(): boolean {
+    return this.files.length > 0;
+  }
+  getFileCount(): number {
+    return this.files.length;
+  }
+  getFilenames(): string[] {
+    return this.files.map((f) => f.name);
+  }
+  getFilename(): string {
+    if (this.files.length === 0) return '';
+    if (this.files.length === 1) return this.files[0].name;
+    return `${this.files.length} FB2 files`;
+  }
+
+  async data(
+    _inputs: Record<string, SocketData[]>
+  ): Promise<Record<string, SocketData>> {
+    if (this.files.length === 0)
+      throw new Error('No FB2 files uploaded in FB2 Input node');
+
+    const pymupdf = await loadPyMuPDF();
+    const results: PDFData[] = [];
+    for (const file of this.files) {
+      const blob = await pymupdf.convertToPdf(file, { filetype: 'fb2' });
+      const bytes = new Uint8Array(await blob.arrayBuffer());
+      const document = await PDFDocument.load(bytes);
+      results.push({
+        type: 'pdf',
+        document,
+        bytes,
+        filename: file.name.replace(/\.fb2$/i, '.pdf'),
+      });
+    }
+
+    if (results.length === 1) return { pdf: results[0] };
+    return { pdf: { type: 'multi-pdf', items: results } as MultiPDFData };
+  }
+}