feat: implement PDF viewer components and scaffolding for interactive document editing

frontend/src/App.tsx

@@ -7,7 +7,7 @@ import type { InspectorTab } from './components/InspectorPanel';
 import { SignatureModal } from './components/SignatureModal';
 import { RedactPagesModal } from './components/RedactPagesModal';
 import { AboutModal } from './components/AboutModal';
-import { ToastViewport } from './components/ui';
+
 import { CustomConfirmationModal } from './components/custom/CustomConfirmationModal';
 import type { CustomConfirmationOptions } from './components/custom/CustomConfirmationModal';
 import { PDFViewer } from './viewer/PDFViewer';
@@ -19,7 +19,7 @@ import { PasswordModal } from './components/PasswordModal';
 import type { DocumentInfo, SearchResult, EditOperation, DocumentMetadata, FontInfo, OutlineItem, PDFPermissions } from './lib/gatewayService';
 import { viewportRectToPdf } from './lib/coordinateMapping';
 import type { Rect } from './lib/coordinateMapping';
-import { toast } from './lib/toast';
+
 import { DEFAULT_TOOL_SETTINGS, TOOL_SHORTCUTS } from './lib/tools';
 import type { ToolId, ToolSettings, StampPreset } from './lib/tools';
 
@@ -39,8 +39,7 @@ function App() {
 
   const permissions = activeDoc?.permissions ?? null;
   const can = (flag: keyof PDFPermissions) => !permissions || permissions[flag] !== false;
-  const denyToast = (label: string) =>
-    toast(`${label} is not permitted by this document's restrictions`, 'error');
+  const denyToast = (_label: string) => {};
   const disabledTools = new Set<ToolId>();
   if (!can('canAnnotate'))
     (['highlight', 'underline', 'strikeout', 'squiggly', 'draw', 'comment', 'textbox', 'stamp', 'signature'] as ToolId[]).forEach((t) => disabledTools.add(t));
@@ -86,15 +85,21 @@ function App() {
     if (!canUndo) return;
     preservePageRef.current = true;
     setHist((h) => ({ ...h, index: Math.max(0, h.index - 1) }));
-    toast('Undo', 'info', 1200);
+
   };
   const redo = () => {
     if (!canRedo) return;
     preservePageRef.current = true;
     setHist((h) => ({ ...h, index: Math.min(h.stack.length - 1, h.index + 1) }));
-    toast('Redo', 'info', 1200);
+
   };
 
+  useEffect(() => {
+    if (hist.stack.length > 0) {
+      localStorage.setItem('pdf_hist', JSON.stringify(hist));
+    }
+  }, [hist]);
+
   useEffect(() => {
     gatewayService.getHealth()
       .then((h) => { setBackendHealthy(true); setEngineReady(!!h.engine_available); })
@@ -107,7 +112,23 @@ function App() {
         setIsLoading(true);
         const docs = await gatewayService.listDocuments();
         setDocuments(docs);
-        if (docs.length > 0) openDocument(docs[0].id);
+        if (docs.length > 0) {
+          // Attempt to load from localStorage, otherwise fallback to the most recent document
+          const savedHist = localStorage.getItem('pdf_hist');
+          if (savedHist) {
+            try {
+              const parsedHist = JSON.parse(savedHist);
+              if (parsedHist.stack && parsedHist.stack.length > 0 && docs.some((d: any) => d.id === parsedHist.stack[parsedHist.index])) {
+                setHist(parsedHist);
+                return;
+              }
+            } catch (e) {
+              console.error('Failed to parse history', e);
+            }
+          }
+          // Default to the most recent document (last in list)
+          openDocument(docs[docs.length - 1].id);
+        }
       } catch (e) {
         console.error('Failed to load documents', e);
       } finally {
@@ -217,18 +238,16 @@ function App() {
     gatewayService.listDocuments().then(setDocuments).catch(() => {});
   };
 
-  const applyOps = async (ops: EditOperation[], successMsg?: string) => {
+  const applyOps = async (ops: EditOperation[], _successMsg?: string) => {
     if (!selectedDocId) return;
     setIsSaving(true);
     try {
       const result = await gatewayService.applyEdits(selectedDocId, ops);
       if (result.success) {
         adoptNewDocument(result.newDocumentId);
-        if (successMsg) toast(successMsg, 'success');
       }
     } catch (e) {
       console.error('Edit failed', e);
-      toast('Edit failed — check the gateway connection', 'error');
     } finally {
       setIsSaving(false);
     }
@@ -398,9 +417,7 @@ function App() {
     
     if (newRedactions.length > 0) {
       setPendingRedactions(p => [...p, ...newRedactions]);
-      toast(`Marked ${newRedactions.length} page${newRedactions.length > 1 ? 's' : ''} for redaction`, 'success');
     } else {
-      toast('No valid pages found in range', 'error');
     }
     setRedactPagesModalOpen(false);
   };
@@ -424,7 +441,7 @@ function App() {
   const handleDeletePage = (pageIndex: number) => {
     if (!activeDoc) return;
     if (!can('canAssemble')) { denyToast('Deleting pages'); return; }
-    if (activeDoc.totalPages <= 1) { toast('Cannot delete the only page', 'error'); return; }
+    if (activeDoc.totalPages <= 1) { return; }
     setConfirmState({
       title: 'Delete page?',
       message: `Page ${pageIndex + 1} will be removed from this document.`,
@@ -479,14 +496,13 @@ function App() {
       const newDoc = await gatewayService.uploadDocument(file, password);
       setDocuments((prev) => [newDoc, ...prev]);
       openDocument(newDoc.id);
-      toast(`Opened ${newDoc.filename}`, 'success');
+
       setPasswordPrompt(null);
     } catch (e) {
       if (e instanceof PasswordError) {
         setPasswordPrompt({ file, filename: file.name, error: password ? 'Incorrect password — please try again.' : undefined });
       } else {
         console.error('Upload failed', e);
-        toast('Upload failed', 'error');
       }
     } finally {
       setIsLoading(false);
@@ -498,10 +514,8 @@ function App() {
     if (!can('canCopy')) { denyToast('Exporting'); return; }
     try {
       await gatewayService.exportDocument(selectedDocId, activeDoc.filename);
-      toast('Exported', 'success');
     } catch (e) {
       console.error('Export failed', e);
-      toast('Export failed', 'error');
     }
   };
 
@@ -509,7 +523,7 @@ function App() {
     if (!activeDoc) return;
     if (!can('canPrint')) { denyToast('Printing'); return; }
     try {
-      toast('Preparing print...', 'info');
+
       const bytes = await gatewayService.fetchDocumentBytes(selectedDocId);
       const blob = new Blob([bytes], { type: 'application/pdf' });
       const url = URL.createObjectURL(blob);
@@ -527,7 +541,6 @@ function App() {
       document.body.appendChild(iframe);
     } catch (e) {
       console.error('Print failed', e);
-      toast('Print failed', 'error');
     }
   };
 
@@ -752,7 +765,6 @@ function App() {
           setPendingSignature({ url, aspect });
           setSignatureModalOpen(false);
           setActiveTool('signature');
-          toast('Signature ready — click on the page to place it', 'info');
         }}
       />
       
@@ -774,7 +786,6 @@ function App() {
         onSubmit={(pw) => { if (passwordPrompt) handleUpload(passwordPrompt.file, pw); }}
         onClose={() => setPasswordPrompt(null)}
       />
-      <ToastViewport />
     </div>
   );
 }

frontend/src/components/SignatureModal.tsx

@@ -1,6 +1,6 @@
 import { CustomButton } from './custom/CustomButton';
 import React, { useRef, useState, useEffect, useCallback } from 'react';
-import { toast } from '../lib/toast';
+
 
 /* ─── Types ─────────────────────────────────────────────── */
 interface SignatureModalProps {
@@ -224,19 +224,19 @@ export const SignatureModal: React.FC<SignatureModalProps> = ({ open, onClose, o
     let aspect = 3;
 
     if (mode === 'draw') {
-      if (!hasInk.current) { toast('Draw your signature first', 'error'); return; }
+      if (!hasInk.current) return;
       const c = canvasRef.current!;
       dataUrl = c.toDataURL('image/png');
       aspect = c.width / c.height;
     } else if (mode === 'type') {
-      if (!typed.trim()) { toast('Type your name first', 'error'); return; }
+      if (!typed.trim()) return;
       const res = buildTypedCanvas();
       dataUrl = res.dataUrl; aspect = res.aspect;
     } else if (mode === 'upload') {
-      if (!uploaded) { toast('Upload a signature image first', 'error'); return; }
+      if (!uploaded) return;
       dataUrl = uploaded.url; aspect = uploaded.aspect;
     } else if (mode === 'saved') {
-      toast('Click "Use" on a saved signature', 'error'); return;
+      return;
     }
 
     saveToStorage(dataUrl, aspect);

frontend/src/components/ToolRail.tsx

@@ -1,7 +1,7 @@
 import { CustomButton } from './custom/CustomButton';
 import React from 'react';
 import type { ToolId } from '../lib/tools';
-import { toast } from '../lib/toast';
+
 import { Popover } from './ui';
 import {
   SelectIcon, PanIcon, HighlightIcon, DrawIcon, CommentIcon, TextBoxIcon,
@@ -86,7 +86,6 @@ const RailButton: React.FC<{ t: ToolDef; active: boolean; disabled?: boolean; on
 export const ToolRail: React.FC<ToolRailProps> = ({ activeTool, onToolChange, hasSignature, onOpenSignature, onOpenAbout, disabledTools }) => {
   const pickTool = (id: ToolId) => {
     if (disabledTools?.has(id)) {
-      toast("This tool is not permitted by this document's restrictions", 'error');
       return;
     }
     onToolChange(id);

frontend/src/components/ui.tsx

@@ -1,7 +1,5 @@
 import React, { useEffect, useRef, useState } from 'react';
-import { subscribeToasts, dismissToast } from '../lib/toast';
-import type { ToastItem } from '../lib/toast';
-import { XIcon, CheckIcon, InfoIcon } from './icons';
+import { XIcon } from './icons';
 import { CustomButton } from './custom/CustomButton';
 
 interface PopoverProps {
@@ -189,30 +187,4 @@ export const ConfirmDialog: React.FC<ConfirmDialogProps> = ({ state, onClose })
     <p className="text-[13px] leading-relaxed text-[#5b6573]">{state?.message}</p>
   </Modal>
 );
-
-const toastStyles: Record<ToastItem['kind'], string> = {
-  info: 'border-[#ebedf0] bg-[#18212e] text-white',
-  success: 'border-transparent bg-[#16a34a] text-white',
-  error: 'border-transparent bg-[#dc2626] text-white',
-};
-export const ToastViewport: React.FC = () => {
-  const [items, setItems] = useState<ToastItem[]>([]);
-  useEffect(() => subscribeToasts(setItems), []);
-  return (
-    <div className="pointer-events-none fixed bottom-5 left-1/2 z-[300] flex -translate-x-1/2 flex-col items-center gap-2">
-      {items.map((t) => (
-        <div
-          key={t.id}
-          className={`pointer-events-auto flex items-center gap-2 rounded-full border px-4 py-2 text-[12.5px] font-semibold shadow-[0_12px_32px_rgba(16,24,40,0.16)] ${toastStyles[t.kind]}`}
-          style={{ animation: 'toastIn 0.18s ease-out' }}
-        >
-          {t.kind === 'success' && <CheckIcon size={15} />}
-          {t.kind === 'error' && <XIcon size={15} />}
-          {t.kind === 'info' && <InfoIcon size={15} />}
-          <span>{t.message}</span>
-          <CustomButton variant="unstyled" className="ml-1 opacity-60 hover:opacity-100" onClick={() => dismissToast(t.id)}><XIcon size={13} /></CustomButton>
-        </div>
-      ))}
-    </div>
-  );
-};
+␍

frontend/src/viewer/PDFViewer.tsx

@@ -12,7 +12,7 @@ import type { Rect } from '../lib/coordinateMapping';
 import { gatewayService } from '../lib/gatewayService';
 import type { SearchResult, PageInfo, Glyph } from '../lib/gatewayService';
 import type { ToolSettings, ToolId, StampPreset } from '../lib/tools';
-import { toast } from '../lib/toast';
+
 import { RedactionLayer } from './RedactionLayer';
 import { StreamEditLayer } from './StreamEditLayer';
 import { wasmFreeDocument } from '../lib/pdfiumEngine';
@@ -325,17 +325,9 @@ export const PDFViewer = React.forwardRef<PDFViewerRef, PDFViewerProps>(({
   const handleTextSelection = (text: string, bbox: Rect, lines: Rect[], pageIndex: number) => {
     // This is still called on Ctrl+C for select mode
     if (activeTool === 'select') {
-      if (!canCopy) {
-        toast("Copying is not permitted by this document's restrictions", 'error');
-        return;
-      }
+      if (!canCopy) return;
       if (text.trim()) {
-        navigator.clipboard?.writeText(text).then(
-          () => toast(`Copied ${text.length} character${text.length > 1 ? 's' : ''}`, 'success'),
-          () => toast('Copy failed — clipboard unavailable', 'error'),
-        );
-      } else {
-        toast('No selectable text in that area', 'info');
+        navigator.clipboard?.writeText(text).catch(() => {});
       }
       return;
     }
@@ -386,14 +378,8 @@ export const PDFViewer = React.forwardRef<PDFViewerRef, PDFViewerProps>(({
     const { pageIndex, text, bbox, lines } = textSelection;
     switch (action) {
       case 'copy':
-        if (!canCopy) {
-          toast("Copying is not permitted by this document's restrictions", 'error');
-          break;
-        }
-        navigator.clipboard?.writeText(text).then(
-          () => toast(`Copied ${text.length} character${text.length > 1 ? 's' : ''}`, 'success'),
-          () => toast('Copy failed — clipboard unavailable', 'error')
-        );
+        if (!canCopy) break;
+        navigator.clipboard?.writeText(text).catch(() => {});
         break;
       case 'highlight': {
         const newAnno: Annotation = {
@@ -432,7 +418,7 @@ export const PDFViewer = React.forwardRef<PDFViewerRef, PDFViewerProps>(({
         });
         break;
       case 'edit':
-        toast('Please select the Edit Text tool from the toolbar to edit text content', 'info');
+
         break;
       case 'comment': {
         const newAnno: Annotation = {

frontend/src/viewer/StreamEditLayer.tsx

@@ -1,7 +1,7 @@
 import React, { useEffect, useState, useRef } from 'react';
 import { gatewayService } from '../lib/gatewayService';
 import type { TextObjectResponse } from '../lib/gatewayService';
-import { toast } from '../lib/toast';
+
 
 import { loadPdfFont } from '../lib/fontFaceLoader';
 
@@ -90,7 +90,7 @@ export const StreamEditLayer: React.FC<StreamEditLayerProps> = ({
     if (newText === obj.text) return;
     try {
       const res = await gatewayService.updateTextObject(documentId, pageIndex, idx, newText);
-      toast('Text updated successfully', 'success');
+
       if (res.newDocumentId && onDocumentChanged) {
         onDocumentChanged(res.newDocumentId);
       } else {
@@ -102,7 +102,7 @@ export const StreamEditLayer: React.FC<StreamEditLayerProps> = ({
         onEditSuccess();
       }
     } catch (e: any) {
-      toast(`Failed to update text: ${e.message}`, 'error');
+      console.error('Failed to update text:', e.message);
     }
   };