Viewer update and autozoom (#4800)

Updated embed PDF
Added Autozoom
Added file page size to metadata for use in calculations for autozoom,
will come in handy elsewhere.

---------

Co-authored-by: James Brunton <[email protected]>

frontend/src/core/contexts/viewer/viewerBridges.ts

@@ -0,0 +1,174 @@
+import { SpreadMode } from '@embedpdf/plugin-spread/react';
+
+export interface ScrollAPIWrapper {
+  scrollToPage: (params: { pageNumber: number }) => void;
+  scrollToPreviousPage: () => void;
+  scrollToNextPage: () => void;
+}
+
+export interface ZoomAPIWrapper {
+  zoomIn: () => void;
+  zoomOut: () => void;
+  toggleMarqueeZoom: () => void;
+  requestZoom: (level: number) => void;
+}
+
+export interface PanAPIWrapper {
+  enable: () => void;
+  disable: () => void;
+  toggle: () => void;
+  makePanDefault: () => void;
+}
+
+export interface SelectionAPIWrapper {
+  copyToClipboard: () => void;
+  getSelectedText: () => string | any;
+  getFormattedSelection: () => any;
+}
+
+export interface SpreadAPIWrapper {
+  setSpreadMode: (mode: SpreadMode) => void;
+  getSpreadMode: () => SpreadMode | null;
+  toggleSpreadMode: () => void;
+  SpreadMode: typeof SpreadMode;
+}
+
+export interface RotationAPIWrapper {
+  rotateForward: () => void;
+  rotateBackward: () => void;
+  setRotation: (rotation: number) => void;
+  getRotation: () => number;
+}
+
+export interface SearchAPIWrapper {
+  search: (query: string) => Promise<any>;
+  clear: () => void;
+  next: () => void;
+  previous: () => void;
+  goToResult: (index: number) => void;
+}
+
+export interface ThumbnailAPIWrapper {
+  renderThumb: (pageIndex: number, scale: number) => {
+    toPromise: () => Promise<Blob>;
+  };
+}
+
+export interface ExportAPIWrapper {
+  download: () => void;
+  saveAsCopy: () => { toPromise: () => Promise<ArrayBuffer> };
+}
+
+export interface ScrollState {
+  currentPage: number;
+  totalPages: number;
+}
+
+export interface ZoomState {
+  currentZoom: number;
+  zoomPercent: number;
+}
+
+export interface PanState {
+  isPanning: boolean;
+}
+
+export interface SelectionState {
+  hasSelection: boolean;
+}
+
+export interface SpreadState {
+  spreadMode: SpreadMode;
+  isDualPage: boolean;
+}
+
+export interface RotationState {
+  rotation: number;
+}
+
+export interface SearchResult {
+  pageIndex: number;
+  rects: Array<{
+    origin: { x: number; y: number };
+    size: { width: number; height: number };
+  }>;
+}
+
+export interface SearchState {
+  results: SearchResult[] | null;
+  activeIndex: number;
+}
+
+export interface ExportState {
+  canExport: boolean;
+}
+
+export interface BridgeRef<TState = unknown, TApi = unknown> {
+  state: TState;
+  api: TApi;
+}
+
+export interface BridgeStateMap {
+  scroll: ScrollState;
+  zoom: ZoomState;
+  pan: PanState;
+  selection: SelectionState;
+  spread: SpreadState;
+  rotation: RotationState;
+  search: SearchState;
+  thumbnail: unknown;
+  export: ExportState;
+}
+
+export interface BridgeApiMap {
+  scroll: ScrollAPIWrapper;
+  zoom: ZoomAPIWrapper;
+  pan: PanAPIWrapper;
+  selection: SelectionAPIWrapper;
+  spread: SpreadAPIWrapper;
+  rotation: RotationAPIWrapper;
+  search: SearchAPIWrapper;
+  thumbnail: ThumbnailAPIWrapper;
+  export: ExportAPIWrapper;
+}
+
+export type BridgeKey = keyof BridgeStateMap;
+
+export type ViewerBridgeRegistry = {
+  [K in BridgeKey]: BridgeRef<BridgeStateMap[K], BridgeApiMap[K]> | null;
+};
+
+export const createBridgeRegistry = (): ViewerBridgeRegistry => ({
+  scroll: null,
+  zoom: null,
+  pan: null,
+  selection: null,
+  spread: null,
+  rotation: null,
+  search: null,
+  thumbnail: null,
+  export: null,
+});
+
+export function registerBridge<K extends BridgeKey>(
+  registry: ViewerBridgeRegistry,
+  type: K,
+  ref: BridgeRef<BridgeStateMap[K], BridgeApiMap[K]>
+): void {
+  registry[type] = ref as ViewerBridgeRegistry[K];
+}
+
+export function getBridgeState<K extends BridgeKey>(
+  registry: ViewerBridgeRegistry,
+  type: K,
+  fallback: BridgeStateMap[K]
+): BridgeStateMap[K] {
+  return registry[type]?.state ?? fallback;
+}
+
+export function getBridgeApi<K extends BridgeKey>(
+  registry: ViewerBridgeRegistry,
+  type: K
+): BridgeApiMap[K] | null {
+  return registry[type]?.api ?? null;
+}