diora-web/static/js/app/50-reader-state.js

'use strict';

// Reader settings
let readerSettings = { fontSize: 16, lineHeight: 1.8, maxWidth: 65, theme: 'dark',
                        fontFamily: 'serif', noBold: false, fontWeight: null,
                        pdfZoom: 100, pdfInverted: false, pdfPageColors: false, pdfPaginated: false, pdfSpread: false };
let readerSettingsPanelOpen = false;
let currentPdfDoc = null;
let currentPdfBuffer = null;

// Bookmarks
let currentBookmarks = [];
let bookmarksDirty = false;

// Highlights
let currentHighlights = [];
let highlightsDirty = false;
let currentHighlightPopover = null;

// Search
let searchMatches = [];
let searchMatchIndex = -1;
let searchOriginalContent = null;
let readerSearchOpen = false;

// PDF paginated
let pdfCurrentPage = 1;
let pdfTotalPages = 0;
let _pdfPageTextBoxCache = {};
let _pdfRenderGen = 0;
let _touchStartX = 0;
let _readerScrollInterval = null;
let _readerScrollDir = 0;
let _readerScrollLastTs = 0;
const READER_SCROLL_SPEED = 1200;    // constant px/s, no ramp-up
const READER_SCROLL_TICK_MS = 20;    // fixed cadence, independent of the
                                      // display's refresh rate — rAF runs at
                                      // that rate (120/144/165Hz on plenty of
                                      // laptops), which was driving 2-3x more
                                      // scrollBy + scroll-listener work per
                                      // second than intended and read as lag.
function _readerScrollTick() {
  const now = performance.now();
  const dt = now - _readerScrollLastTs;
  _readerScrollLastTs = now;
  $('reader-content')?.scrollBy({top: Math.round(_readerScrollDir * READER_SCROLL_SPEED * dt / 1000)});
}
let _pinchStartDist = 0;
let _pinchStartZoom = 100;
let _isPinching = false;

if (typeof pdfjsLib !== 'undefined') {
  pdfjsLib.GlobalWorkerOptions.workerSrc = '/static/js/pdf.worker.min.js';
}