feat(viewer): Add pagination metadata and thumbnail offset rendering for viewer thumbnails

ts_web/elements/document.ts

@@ -26,6 +26,12 @@ import { DeContentInvoice } from "./contentinvoice.js";
 
 import { demoFunc } from "./document.demo.js";
 
+export interface IPagePaginationInfo {
+  pageNumber: number;
+  startOffset: number;
+  contentLength: number;
+}
+
 declare global {
   interface HTMLElementTagNameMap {
     "dedocument-dedocument": DeDocument;
@@ -142,10 +148,12 @@ export class DeDocument extends DeesElement {
     null;
   public latestRenderedLetterData: plugins.tsclass.business.TLetter = null;
   public cleanupStore: any[] = [];
+  public paginationInfo: IPagePaginationInfo[] = [];
 
   public async renderDocument() {
     this.latestDocumentSettings = this.documentSettings;
     this.latestRenderedLetterData = this.letterData;
+    this.paginationInfo = [];
 
     const cleanUpStoreCurrentRender = [];
     const cleanUpStoreNextRender = [];
@@ -198,7 +206,16 @@ export class DeDocument extends DeesElement {
         newPageOverflows = await newPage.checkOverflow();
       }
       currentContentOffset = await currentContent.getContentLength();
+      const pageStartOffset = overallContentOffset;
       overallContentOffset = overallContentOffset + currentContentOffset;
+
+      // Track pagination info for this page
+      this.paginationInfo.push({
+        pageNumber: pageCounter,
+        startOffset: pageStartOffset,
+        contentLength: currentContentOffset,
+      });
+
       if (trimmed === 0) {
         complete = true;
       }
@@ -234,6 +251,16 @@ export class DeDocument extends DeesElement {
       }
     }
     this.adjustDePageScaling();
+
+    // Emit event with pagination info for thumbnails
+    this.dispatchEvent(new CustomEvent('pagination-complete', {
+      detail: {
+        pageCount: pageCounter,
+        paginationInfo: this.paginationInfo,
+      },
+      bubbles: true,
+      composed: true,
+    }));
   }
 
   async updated(