pdfjs-dist/lib/web/pdf_history.js

/**
 * @licstart The following is the entire license notice for the
 * Javascript code in this page
 *
 * Copyright 2019 Mozilla Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *
 * @licend The above is the entire license notice for the
 * Javascript code in this page
 */
"use strict";

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.isDestHashesEqual = isDestHashesEqual;
exports.isDestArraysEqual = isDestArraysEqual;
exports.PDFHistory = void 0;

var _ui_utils = require("./ui_utils");

function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }

function _slicedToArray(arr, i) { return _arrayWithHoles(arr) || _iterableToArrayLimit(arr, i) || _nonIterableRest(); }

function _nonIterableRest() { throw new TypeError("Invalid attempt to destructure non-iterable instance"); }

function _iterableToArrayLimit(arr, i) { if (!(Symbol.iterator in Object(arr) || Object.prototype.toString.call(arr) === "[object Arguments]")) { return; } var _arr = []; var _n = true; var _d = false; var _e = undefined; try { for (var _i = arr[Symbol.iterator](), _s; !(_n = (_s = _i.next()).done); _n = true) { _arr.push(_s.value); if (i && _arr.length === i) break; } } catch (err) { _d = true; _e = err; } finally { try { if (!_n && _i["return"] != null) _i["return"](); } finally { if (_d) throw _e; } } return _arr; }

function _arrayWithHoles(arr) { if (Array.isArray(arr)) return arr; }

function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }

function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, descriptor.key, descriptor); } }

function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); return Constructor; }

var HASH_CHANGE_TIMEOUT = 1000;
var POSITION_UPDATED_THRESHOLD = 50;
var UPDATE_VIEWAREA_TIMEOUT = 1000;

function getCurrentHash() {
  return document.location.hash;
}

function parseCurrentHash(linkService) {
  var hash = unescape(getCurrentHash()).substring(1);
  var params = (0, _ui_utils.parseQueryString)(hash);
  var page = params.page | 0;

  if (!(Number.isInteger(page) && page > 0 && page <= linkService.pagesCount)) {
    page = null;
  }

  return {
    hash: hash,
    page: page,
    rotation: linkService.rotation
  };
}

var PDFHistory =
/*#__PURE__*/
function () {
  function PDFHistory(_ref) {
    var _this = this;

    var linkService = _ref.linkService,
        eventBus = _ref.eventBus;

    _classCallCheck(this, PDFHistory);

    this.linkService = linkService;
    this.eventBus = eventBus || (0, _ui_utils.getGlobalEventBus)();
    this.initialized = false;
    this.initialBookmark = null;
    this.initialRotation = null;
    this._boundEvents = Object.create(null);
    this._isViewerInPresentationMode = false;
    this._isPagesLoaded = false;
    this.eventBus.on('presentationmodechanged', function (evt) {
      _this._isViewerInPresentationMode = evt.active || evt.switchInProgress;
    });
    this.eventBus.on('pagesloaded', function (evt) {
      _this._isPagesLoaded = !!evt.pagesCount;
    });
  }

  _createClass(PDFHistory, [{
    key: "initialize",
    value: function initialize(_ref2) {
      var fingerprint = _ref2.fingerprint,
          _ref2$resetHistory = _ref2.resetHistory,
          resetHistory = _ref2$resetHistory === void 0 ? false : _ref2$resetHistory,
          _ref2$updateUrl = _ref2.updateUrl,
          updateUrl = _ref2$updateUrl === void 0 ? false : _ref2$updateUrl;

      if (!fingerprint || typeof fingerprint !== 'string') {
        console.error('PDFHistory.initialize: The "fingerprint" must be a non-empty string.');
        return;
      }

      var reInitialized = this.initialized && this.fingerprint !== fingerprint;
      this.fingerprint = fingerprint;
      this._updateUrl = updateUrl === true;

      if (!this.initialized) {
        this._bindEvents();
      }

      var state = window.history.state;
      this.initialized = true;
      this.initialBookmark = null;
      this.initialRotation = null;
      this._popStateInProgress = false;
      this._blockHashChange = 0;
      this._currentHash = getCurrentHash();
      this._numPositionUpdates = 0;
      this._uid = this._maxUid = 0;
      this._destination = null;
      this._position = null;

      if (!this._isValidState(state, true) || resetHistory) {
        var _parseCurrentHash = parseCurrentHash(this.linkService),
            hash = _parseCurrentHash.hash,
            page = _parseCurrentHash.page,
            rotation = _parseCurrentHash.rotation;

        if (!hash || reInitialized || resetHistory) {
          this._pushOrReplaceState(null, true);

          return;
        }

        this._pushOrReplaceState({
          hash: hash,
          page: page,
          rotation: rotation
        }, true);

        return;
      }

      var destination = state.destination;

      this._updateInternalState(destination, state.uid, true);

      if (this._uid > this._maxUid) {
        this._maxUid = this._uid;
      }

      if (destination.rotation !== undefined) {
        this.initialRotation = destination.rotation;
      }

      if (destination.dest) {
        this.initialBookmark = JSON.stringify(destination.dest);
        this._destination.page = null;
      } else if (destination.hash) {
        this.initialBookmark = destination.hash;
      } else if (destination.page) {
        this.initialBookmark = "page=".concat(destination.page);
      }
    }
  }, {
    key: "push",
    value: function push(_ref3) {
      var _this2 = this;

      var _ref3$namedDest = _ref3.namedDest,
          namedDest = _ref3$namedDest === void 0 ? null : _ref3$namedDest,
          explicitDest = _ref3.explicitDest,
          pageNumber = _ref3.pageNumber;

      if (!this.initialized) {
        return;
      }

      if (namedDest && typeof namedDest !== 'string') {
        console.error('PDFHistory.push: ' + "\"".concat(namedDest, "\" is not a valid namedDest parameter."));
        return;
      } else if (!Array.isArray(explicitDest)) {
        console.error('PDFHistory.push: ' + "\"".concat(explicitDest, "\" is not a valid explicitDest parameter."));
        return;
      } else if (!(Number.isInteger(pageNumber) && pageNumber > 0 && pageNumber <= this.linkService.pagesCount)) {
        if (pageNumber !== null || this._destination) {
          console.error('PDFHistory.push: ' + "\"".concat(pageNumber, "\" is not a valid pageNumber parameter."));
          return;
        }
      }

      var hash = namedDest || JSON.stringify(explicitDest);

      if (!hash) {
        return;
      }

      var forceReplace = false;

      if (this._destination && (isDestHashesEqual(this._destination.hash, hash) || isDestArraysEqual(this._destination.dest, explicitDest))) {
        if (this._destination.page) {
          return;
        }

        forceReplace = true;
      }

      if (this._popStateInProgress && !forceReplace) {
        return;
      }

      this._pushOrReplaceState({
        dest: explicitDest,
        hash: hash,
        page: pageNumber,
        rotation: this.linkService.rotation
      }, forceReplace);

      if (!this._popStateInProgress) {
        this._popStateInProgress = true;
        Promise.resolve().then(function () {
          _this2._popStateInProgress = false;
        });
      }
    }
  }, {
    key: "pushCurrentPosition",
    value: function pushCurrentPosition() {
      if (!this.initialized || this._popStateInProgress) {
        return;
      }

      this._tryPushCurrentPosition();
    }
  }, {
    key: "back",
    value: function back() {
      if (!this.initialized || this._popStateInProgress) {
        return;
      }

      var state = window.history.state;

      if (this._isValidState(state) && state.uid > 0) {
        window.history.back();
      }
    }
  }, {
    key: "forward",
    value: function forward() {
      if (!this.initialized || this._popStateInProgress) {
        return;
      }

      var state = window.history.state;

      if (this._isValidState(state) && state.uid < this._maxUid) {
        window.history.forward();
      }
    }
  }, {
    key: "_pushOrReplaceState",
    value: function _pushOrReplaceState(destination) {
      var forceReplace = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;
      var shouldReplace = forceReplace || !this._destination;
      var newState = {
        fingerprint: this.fingerprint,
        uid: shouldReplace ? this._uid : this._uid + 1,
        destination: destination
      };

      this._updateInternalState(destination, newState.uid);

      var newUrl;

      if (this._updateUrl && destination && destination.hash) {
        var baseUrl = document.location.href.split('#')[0];

        if (!baseUrl.startsWith('file://')) {
          newUrl = "".concat(baseUrl, "#").concat(destination.hash);
        }
      }

      if (shouldReplace) {
        if (newUrl) {
          window.history.replaceState(newState, '', newUrl);
        } else {
          window.history.replaceState(newState, '');
        }
      } else {
        this._maxUid = this._uid;

        if (newUrl) {
          window.history.pushState(newState, '', newUrl);
        } else {
          window.history.pushState(newState, '');
        }
      }
    }
  }, {
    key: "_tryPushCurrentPosition",
    value: function _tryPushCurrentPosition() {
      var temporary = arguments.length > 0 && arguments[0] !== undefined ? arguments[0] : false;

      if (!this._position) {
        return;
      }

      var position = this._position;

      if (temporary) {
        position = Object.assign(Object.create(null), this._position);
        position.temporary = true;
      }

      if (!this._destination) {
        this._pushOrReplaceState(position);

        return;
      }

      if (this._destination.temporary) {
        this._pushOrReplaceState(position, true);

        return;
      }

      if (this._destination.hash === position.hash) {
        return;
      }

      if (!this._destination.page && (POSITION_UPDATED_THRESHOLD <= 0 || this._numPositionUpdates <= POSITION_UPDATED_THRESHOLD)) {
        return;
      }

      var forceReplace = false;

      if (this._destination.page >= position.first && this._destination.page <= position.page) {
        if (this._destination.dest || !this._destination.first) {
          return;
        }

        forceReplace = true;
      }

      this._pushOrReplaceState(position, forceReplace);
    }
  }, {
    key: "_isValidState",
    value: function _isValidState(state) {
      var checkReload = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : false;

      if (!state) {
        return false;
      }

      if (state.fingerprint !== this.fingerprint) {
        if (checkReload) {
          if (typeof state.fingerprint !== 'string' || state.fingerprint.length !== this.fingerprint.length) {
            return false;
          }

          var _performance$getEntri = performance.getEntriesByType('navigation'),
              _performance$getEntri2 = _slicedToArray(_performance$getEntri, 1),
              perfEntry = _performance$getEntri2[0];

          if (!perfEntry || perfEntry.type !== 'reload') {
            return false;
          }
        } else {
          return false;
        }
      }

      if (!Number.isInteger(state.uid) || state.uid < 0) {
        return false;
      }

      if (state.destination === null || _typeof(state.destination) !== 'object') {
        return false;
      }

      return true;
    }
  }, {
    key: "_updateInternalState",
    value: function _updateInternalState(destination, uid) {
      var removeTemporary = arguments.length > 2 && arguments[2] !== undefined ? arguments[2] : false;

      if (this._updateViewareaTimeout) {
        clearTimeout(this._updateViewareaTimeout);
        this._updateViewareaTimeout = null;
      }

      if (removeTemporary && destination && destination.temporary) {
        delete destination.temporary;
      }

      this._destination = destination;
      this._uid = uid;
      this._numPositionUpdates = 0;
    }
  }, {
    key: "_updateViewarea",
    value: function _updateViewarea(_ref4) {
      var _this3 = this;

      var location = _ref4.location;

      if (this._updateViewareaTimeout) {
        clearTimeout(this._updateViewareaTimeout);
        this._updateViewareaTimeout = null;
      }

      this._position = {
        hash: this._isViewerInPresentationMode ? "page=".concat(location.pageNumber) : location.pdfOpenParams.substring(1),
        page: this.linkService.page,
        first: location.pageNumber,
        rotation: location.rotation
      };

      if (this._popStateInProgress) {
        return;
      }

      if (POSITION_UPDATED_THRESHOLD > 0 && this._isPagesLoaded && this._destination && !this._destination.page) {
        this._numPositionUpdates++;
      }

      if (UPDATE_VIEWAREA_TIMEOUT > 0) {
        this._updateViewareaTimeout = setTimeout(function () {
          if (!_this3._popStateInProgress) {
            _this3._tryPushCurrentPosition(true);
          }

          _this3._updateViewareaTimeout = null;
        }, UPDATE_VIEWAREA_TIMEOUT);
      }
    }
  }, {
    key: "_popState",
    value: function _popState(_ref5) {
      var _this4 = this;

      var state = _ref5.state;
      var newHash = getCurrentHash(),
          hashChanged = this._currentHash !== newHash;
      this._currentHash = newHash;

      if (!state || false) {
        this._uid++;

        var _parseCurrentHash2 = parseCurrentHash(this.linkService),
            hash = _parseCurrentHash2.hash,
            page = _parseCurrentHash2.page,
            rotation = _parseCurrentHash2.rotation;

        this._pushOrReplaceState({
          hash: hash,
          page: page,
          rotation: rotation
        }, true);

        return;
      }

      if (!this._isValidState(state)) {
        return;
      }

      this._popStateInProgress = true;

      if (hashChanged) {
        this._blockHashChange++;
        (0, _ui_utils.waitOnEventOrTimeout)({
          target: window,
          name: 'hashchange',
          delay: HASH_CHANGE_TIMEOUT
        }).then(function () {
          _this4._blockHashChange--;
        });
      }

      var destination = state.destination;

      this._updateInternalState(destination, state.uid, true);

      if (this._uid > this._maxUid) {
        this._maxUid = this._uid;
      }

      if ((0, _ui_utils.isValidRotation)(destination.rotation)) {
        this.linkService.rotation = destination.rotation;
      }

      if (destination.dest) {
        this.linkService.navigateTo(destination.dest);
      } else if (destination.hash) {
        this.linkService.setHash(destination.hash);
      } else if (destination.page) {
        this.linkService.page = destination.page;
      }

      Promise.resolve().then(function () {
        _this4._popStateInProgress = false;
      });
    }
  }, {
    key: "_bindEvents",
    value: function _bindEvents() {
      var _this5 = this;

      var _boundEvents = this._boundEvents,
          eventBus = this.eventBus;
      _boundEvents.updateViewarea = this._updateViewarea.bind(this);
      _boundEvents.popState = this._popState.bind(this);

      _boundEvents.pageHide = function (evt) {
        if (!_this5._destination || _this5._destination.temporary) {
          _this5._tryPushCurrentPosition();
        }
      };

      eventBus.on('updateviewarea', _boundEvents.updateViewarea);
      window.addEventListener('popstate', _boundEvents.popState);
      window.addEventListener('pagehide', _boundEvents.pageHide);
    }
  }, {
    key: "popStateInProgress",
    get: function get() {
      return this.initialized && (this._popStateInProgress || this._blockHashChange > 0);
    }
  }]);

  return PDFHistory;
}();

exports.PDFHistory = PDFHistory;

function isDestHashesEqual(destHash, pushHash) {
  if (typeof destHash !== 'string' || typeof pushHash !== 'string') {
    return false;
  }

  if (destHash === pushHash) {
    return true;
  }

  var _parseQueryString = (0, _ui_utils.parseQueryString)(destHash),
      nameddest = _parseQueryString.nameddest;

  if (nameddest === pushHash) {
    return true;
  }

  return false;
}

function isDestArraysEqual(firstDest, secondDest) {
  function isEntryEqual(first, second) {
    if (_typeof(first) !== _typeof(second)) {
      return false;
    }

    if (Array.isArray(first) || Array.isArray(second)) {
      return false;
    }

    if (first !== null && _typeof(first) === 'object' && second !== null) {
      if (Object.keys(first).length !== Object.keys(second).length) {
        return false;
      }

      for (var key in first) {
        if (!isEntryEqual(first[key], second[key])) {
          return false;
        }
      }

      return true;
    }

    return first === second || Number.isNaN(first) && Number.isNaN(second);
  }

  if (!(Array.isArray(firstDest) && Array.isArray(secondDest))) {
    return false;
  }

  if (firstDest.length !== secondDest.length) {
    return false;
  }

  for (var i = 0, ii = firstDest.length; i < ii; i++) {
    if (!isEntryEqual(firstDest[i], secondDest[i])) {
      return false;
    }
  }

  return true;
}