Dave Jarvis' Repositories

import Page from './Page.js';
import Highlighter from './Highlighter.js';

const element = ( id ) => document.getElementById( id );

export default class Pdf {
  constructor( containerId ) {
    const workerSrc = new URL('./pdf.worker.min.mjs', import.meta.url).href;
    pdfjsLib.GlobalWorkerOptions.workerSrc = workerSrc;

    this.container = element( containerId );
    this.url = this.container.getAttribute( 'data-filename' );
    this.pages = [];
    this.scale = this.calculateScale();

    window.addEventListener('resize', this.handleResize.bind(this));

    this.load();
  }

  calculateScale() {
    const maxWidth = window.innerWidth - 40;
    return maxWidth;
  }

  handleResize() {
    const newScale = this.calculateScale();
    if (Math.abs(this.scale - newScale) > 20) {
      this.scale = newScale;
      this.container.innerHTML = '';
      this.pages = [];
      this.load();
    }
  }

  async load() {
    try {
      const loadingTask = pdfjsLib.getDocument( this.url );
      const pdfDoc = await loadingTask.promise;
      this.pdfDoc = pdfDoc;
      this.numPages = pdfDoc.numPages;
      await this.render();
    } catch (error) {
      console.error('Error loading PDF:', error);
    }
  }

  async render() {
    const firstPage = await this.pdfDoc.getPage(1);
    const viewport = firstPage.getViewport({ scale: 1.0 });
    
    const scaleFactor = this.scale / viewport.width;
    
    for( let pageNum = 1; pageNum <= this.pdfDoc.numPages; pageNum++ ) {
      try {
        const pdfPage = await this.pdfDoc.getPage( pageNum );
        const page = new Page( this.container, pdfPage, pageNum, scaleFactor );
        await page.render();
        this.pages.push( page );
      } catch (error) {
        console.error(`Error rendering page ${pageNum}:`, error);
      }
    }
    
    this.initializeHighlighter();
  }
  
  initializeHighlighter() {
    this.highlighter = new Highlighter( this );
    this.highlighter.setupEventListeners();
    return this.highlighter;
  }
  
  getHighlighter() {
    return this.highlighter;
  }

  getPageCount() {
    return this.pdfDoc ? this.pdfDoc.numPages : 0;
  }

  getPageElements() {
    return this.pages.map( page => page.getPageElement() );
  }

  getTextLayers() {
    return this.pages.map( page => page.getTextLayer() );
  }
}