michael@0: // -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
michael@0: 
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: /** Document Zoom Management Code
michael@0:  *
michael@0:  * To use this, you'll need to have a getBrowser() function or use the methods
michael@0:  * that accept a browser to be modified.
michael@0:  **/
michael@0: 
michael@0: var ZoomManager = {
michael@0:   get _prefBranch() {
michael@0:     delete this._prefBranch;
michael@0:     return this._prefBranch = Components.classes["@mozilla.org/preferences-service;1"]
michael@0:                                         .getService(Components.interfaces.nsIPrefBranch);
michael@0:   },
michael@0: 
michael@0:   get MIN() {
michael@0:     delete this.MIN;
michael@0:     return this.MIN = this._prefBranch.getIntPref("zoom.minPercent") / 100;
michael@0:   },
michael@0: 
michael@0:   get MAX() {
michael@0:     delete this.MAX;
michael@0:     return this.MAX = this._prefBranch.getIntPref("zoom.maxPercent") / 100;
michael@0:   },
michael@0: 
michael@0:   get useFullZoom() {
michael@0:     return this._prefBranch.getBoolPref("browser.zoom.full");
michael@0:   },
michael@0: 
michael@0:   set useFullZoom(aVal) {
michael@0:     this._prefBranch.setBoolPref("browser.zoom.full", aVal);
michael@0:     return aVal;
michael@0:   },
michael@0: 
michael@0:   get zoom() {
michael@0:     return this.getZoomForBrowser(getBrowser());
michael@0:   },
michael@0: 
michael@0:   getZoomForBrowser: function ZoomManager_getZoomForBrowser(aBrowser) {
michael@0:     return (this.useFullZoom || aBrowser.isSyntheticDocument)
michael@0:            ? aBrowser.fullZoom : aBrowser.textZoom;
michael@0:   },
michael@0: 
michael@0:   set zoom(aVal) {
michael@0:     this.setZoomForBrowser(getBrowser(), aVal);
michael@0:     return aVal;
michael@0:   },
michael@0: 
michael@0:   setZoomForBrowser: function ZoomManager_setZoomForBrowser(aBrowser, aVal) {
michael@0:     if (aVal < this.MIN || aVal > this.MAX)
michael@0:       throw Components.results.NS_ERROR_INVALID_ARG;
michael@0: 
michael@0:     if (this.useFullZoom || aBrowser.isSyntheticDocument) {
michael@0:       aBrowser.textZoom = 1;
michael@0:       aBrowser.fullZoom = aVal;
michael@0:     } else {
michael@0:       aBrowser.textZoom = aVal;
michael@0:       aBrowser.fullZoom = 1;
michael@0:     }
michael@0:   },
michael@0: 
michael@0:   get zoomValues() {
michael@0:     var zoomValues = this._prefBranch.getCharPref("toolkit.zoomManager.zoomValues")
michael@0:                                      .split(",").map(parseFloat);
michael@0:     zoomValues.sort(function (a, b) a - b);
michael@0: 
michael@0:     while (zoomValues[0] < this.MIN)
michael@0:       zoomValues.shift();
michael@0: 
michael@0:     while (zoomValues[zoomValues.length - 1] > this.MAX)
michael@0:       zoomValues.pop();
michael@0: 
michael@0:     delete this.zoomValues;
michael@0:     return this.zoomValues = zoomValues;
michael@0:   },
michael@0: 
michael@0:   enlarge: function ZoomManager_enlarge() {
michael@0:     var i = this.zoomValues.indexOf(this.snap(this.zoom)) + 1;
michael@0:     if (i < this.zoomValues.length)
michael@0:       this.zoom = this.zoomValues[i];
michael@0:   },
michael@0: 
michael@0:   reduce: function ZoomManager_reduce() {
michael@0:     var i = this.zoomValues.indexOf(this.snap(this.zoom)) - 1;
michael@0:     if (i >= 0)
michael@0:       this.zoom = this.zoomValues[i];
michael@0:   },
michael@0: 
michael@0:   reset: function ZoomManager_reset() {
michael@0:     this.zoom = 1;
michael@0:   },
michael@0: 
michael@0:   toggleZoom: function ZoomManager_toggleZoom() {
michael@0:     var zoomLevel = this.zoom;
michael@0: 
michael@0:     this.useFullZoom = !this.useFullZoom;
michael@0:     this.zoom = zoomLevel;
michael@0:   },
michael@0: 
michael@0:   snap: function ZoomManager_snap(aVal) {
michael@0:     var values = this.zoomValues;
michael@0:     for (var i = 0; i < values.length; i++) {
michael@0:       if (values[i] >= aVal) {
michael@0:         if (i > 0 && aVal - values[i - 1] < values[i] - aVal)
michael@0:           i--;
michael@0:         return values[i];
michael@0:       }
michael@0:     }
michael@0:     return values[i - 1];
michael@0:   }
michael@0: };