pdf.js/web/secondary_toolbar.js

/* Copyright 2012 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.
 */

import { SCROLLBAR_PADDING, ScrollMode, SpreadMode } from './ui_utils';
import { CursorTool } from './pdf_cursor_tools';
import { PDFSinglePageViewer } from './pdf_single_page_viewer';

/**
 * @typedef {Object} SecondaryToolbarOptions
 * @property {HTMLDivElement} toolbar - Container for the secondary toolbar.
 * @property {HTMLButtonElement} toggleButton - Button to toggle the visibility
 *   of the secondary toolbar.
 * @property {HTMLDivElement} toolbarButtonContainer - Container where all the
 *   toolbar buttons are placed. The maximum height of the toolbar is controlled
 *   dynamically by adjusting the 'max-height' CSS property of this DOM element.
 * @property {HTMLButtonElement} presentationModeButton - Button for entering
 *   presentation mode.
 * @property {HTMLButtonElement} openFileButton - Button to open a file.
 * @property {HTMLButtonElement} printButton - Button to print the document.
 * @property {HTMLButtonElement} downloadButton - Button to download the
 *   document.
 * @property {HTMLLinkElement} viewBookmarkButton - Button to obtain a bookmark
 *   link to the current location in the document.
 * @property {HTMLButtonElement} firstPageButton - Button to go to the first
 *   page in the document.
 * @property {HTMLButtonElement} lastPageButton - Button to go to the last page
 *   in the document.
 * @property {HTMLButtonElement} pageRotateCwButton - Button to rotate the pages
 *   clockwise.
 * @property {HTMLButtonElement} pageRotateCcwButton - Button to rotate the
 *   pages counterclockwise.
 * @property {HTMLButtonElement} cursorSelectToolButton - Button to enable the
 *   select tool.
 * @property {HTMLButtonElement} cursorHandToolButton - Button to enable the
 *   hand tool.
 * @property {HTMLButtonElement} documentPropertiesButton - Button for opening
 *   the document properties dialog.
 */

class SecondaryToolbar {
  /**
   * @param {SecondaryToolbarOptions} options
   * @param {HTMLDivElement} mainContainer
   * @param {EventBus} eventBus
   */
  constructor(options, mainContainer, eventBus) {
    this.toolbar = options.toolbar;
    this.toggleButton = options.toggleButton;
    this.toolbarButtonContainer = options.toolbarButtonContainer;
    this.buttons = [
      { element: options.presentationModeButton, eventName: 'presentationmode',
        close: true, },
      { element: options.openFileButton, eventName: 'openfile', close: true, },
      { element: options.printButton, eventName: 'print', close: true, },
      { element: options.downloadButton, eventName: 'download', close: true, },
      { element: options.viewBookmarkButton, eventName: null, close: true, },
      { element: options.firstPageButton, eventName: 'firstpage',
        close: true, },
      { element: options.lastPageButton, eventName: 'lastpage', close: true, },
      { element: options.pageRotateCwButton, eventName: 'rotatecw',
        close: false, },
      { element: options.pageRotateCcwButton, eventName: 'rotateccw',
        close: false, },
      { element: options.cursorSelectToolButton, eventName: 'switchcursortool',
        eventDetails: { tool: CursorTool.SELECT, }, close: true, },
      { element: options.cursorHandToolButton, eventName: 'switchcursortool',
        eventDetails: { tool: CursorTool.HAND, }, close: true, },
      { element: options.scrollVerticalButton, eventName: 'switchscrollmode',
        eventDetails: { mode: ScrollMode.VERTICAL, }, close: true, },
      { element: options.scrollHorizontalButton, eventName: 'switchscrollmode',
        eventDetails: { mode: ScrollMode.HORIZONTAL, }, close: true, },
      { element: options.scrollWrappedButton, eventName: 'switchscrollmode',
        eventDetails: { mode: ScrollMode.WRAPPED, }, close: true, },
      { element: options.spreadNoneButton, eventName: 'switchspreadmode',
        eventDetails: { mode: SpreadMode.NONE, }, close: true, },
      { element: options.spreadOddButton, eventName: 'switchspreadmode',
        eventDetails: { mode: SpreadMode.ODD, }, close: true, },
      { element: options.spreadEvenButton, eventName: 'switchspreadmode',
        eventDetails: { mode: SpreadMode.EVEN, }, close: true, },
      { element: options.documentPropertiesButton,
        eventName: 'documentproperties', close: true, },
    ];
    this.items = {
      firstPage: options.firstPageButton,
      lastPage: options.lastPageButton,
      pageRotateCw: options.pageRotateCwButton,
      pageRotateCcw: options.pageRotateCcwButton,
    };

    this.mainContainer = mainContainer;
    this.eventBus = eventBus;

    this.opened = false;
    this.containerHeight = null;
    this.previousContainerHeight = null;

    this.reset();

    // Bind the event listeners for click, cursor tool, and scroll/spread mode
    // actions.
    this._bindClickListeners();
    this._bindCursorToolsListener(options);
    this._bindScrollModeListener(options);
    this._bindSpreadModeListener(options);

    // Bind the event listener for adjusting the 'max-height' of the toolbar.
    this.eventBus.on('resize', this._setMaxHeight.bind(this));

    // Hide the Scroll/Spread mode buttons, when they're not applicable to the
    // current `BaseViewer` instance (in particular `PDFSinglePageViewer`).
    this.eventBus.on('baseviewerinit', (evt) => {
      if (evt.source instanceof PDFSinglePageViewer) {
        this.toolbarButtonContainer.classList.add('hiddenScrollModeButtons',
                                                  'hiddenSpreadModeButtons');
      } else {
        this.toolbarButtonContainer.classList.remove('hiddenScrollModeButtons',
                                                     'hiddenSpreadModeButtons');
      }
    });
  }

  /**
   * @type {boolean}
   */
  get isOpen() {
    return this.opened;
  }

  setPageNumber(pageNumber) {
    this.pageNumber = pageNumber;
    this._updateUIState();
  }

  setPagesCount(pagesCount) {
    this.pagesCount = pagesCount;
    this._updateUIState();
  }

  reset() {
    this.pageNumber = 0;
    this.pagesCount = 0;
    this._updateUIState();

    // Reset the Scroll/Spread buttons too, since they're document specific.
    this.eventBus.dispatch('secondarytoolbarreset', { source: this, });
  }

  _updateUIState() {
    this.items.firstPage.disabled = (this.pageNumber <= 1);
    this.items.lastPage.disabled = (this.pageNumber >= this.pagesCount);
    this.items.pageRotateCw.disabled = this.pagesCount === 0;
    this.items.pageRotateCcw.disabled = this.pagesCount === 0;
  }

  _bindClickListeners() {
    // Button to toggle the visibility of the secondary toolbar.
    this.toggleButton.addEventListener('click', this.toggle.bind(this));

    // All items within the secondary toolbar.
    for (let button in this.buttons) {
      let { element, eventName, close, eventDetails, } = this.buttons[button];

      element.addEventListener('click', (evt) => {
        if (eventName !== null) {
          let details = { source: this, };
          for (let property in eventDetails) {
            details[property] = eventDetails[property];
          }
          this.eventBus.dispatch(eventName, details);
        }
        if (close) {
          this.close();
        }
      });
    }
  }

  _bindCursorToolsListener(buttons) {
    this.eventBus.on('cursortoolchanged', function({ tool, }) {
      buttons.cursorSelectToolButton.classList.toggle('toggled',
        tool === CursorTool.SELECT);
      buttons.cursorHandToolButton.classList.toggle('toggled',
        tool === CursorTool.HAND);
    });
  }

  _bindScrollModeListener(buttons) {
    function scrollModeChanged({ mode, }) {
      buttons.scrollVerticalButton.classList.toggle('toggled',
        mode === ScrollMode.VERTICAL);
      buttons.scrollHorizontalButton.classList.toggle('toggled',
        mode === ScrollMode.HORIZONTAL);
      buttons.scrollWrappedButton.classList.toggle('toggled',
        mode === ScrollMode.WRAPPED);

      // Temporarily *disable* the Spread buttons when horizontal scrolling is
      // enabled, since the non-default Spread modes doesn't affect the layout.
      const isScrollModeHorizontal = (mode === ScrollMode.HORIZONTAL);
      buttons.spreadNoneButton.disabled = isScrollModeHorizontal;
      buttons.spreadOddButton.disabled = isScrollModeHorizontal;
      buttons.spreadEvenButton.disabled = isScrollModeHorizontal;
    }
    this.eventBus.on('scrollmodechanged', scrollModeChanged);

    this.eventBus.on('secondarytoolbarreset', (evt) => {
      if (evt.source === this) {
        scrollModeChanged({ mode: ScrollMode.VERTICAL, });
      }
    });
  }

  _bindSpreadModeListener(buttons) {
    function spreadModeChanged({ mode, }) {
      buttons.spreadNoneButton.classList.toggle('toggled',
        mode === SpreadMode.NONE);
      buttons.spreadOddButton.classList.toggle('toggled',
        mode === SpreadMode.ODD);
      buttons.spreadEvenButton.classList.toggle('toggled',
        mode === SpreadMode.EVEN);
    }
    this.eventBus.on('spreadmodechanged', spreadModeChanged);

    this.eventBus.on('secondarytoolbarreset', (evt) => {
      if (evt.source === this) {
        spreadModeChanged({ mode: SpreadMode.NONE, });
      }
    });
  }

  open() {
    if (this.opened) {
      return;
    }
    this.opened = true;
    this._setMaxHeight();

    this.toggleButton.classList.add('toggled');
    this.toolbar.classList.remove('hidden');
  }

  close() {
    if (!this.opened) {
      return;
    }
    this.opened = false;
    this.toolbar.classList.add('hidden');
    this.toggleButton.classList.remove('toggled');
  }

  toggle() {
    if (this.opened) {
      this.close();
    } else {
      this.open();
    }
  }

  /**
   * @private
   */
  _setMaxHeight() {
    if (!this.opened) {
      return; // Only adjust the 'max-height' if the toolbar is visible.
    }
    this.containerHeight = this.mainContainer.clientHeight;

    if (this.containerHeight === this.previousContainerHeight) {
      return;
    }
    this.toolbarButtonContainer.setAttribute('style',
      'max-height: ' + (this.containerHeight - SCROLLBAR_PADDING) + 'px;');

    this.previousContainerHeight = this.containerHeight;
  }
}

export {
  SecondaryToolbar,
};