chrome-extensions-samples/apps/samples/text-editor/lib/ace/layer/cursor.js

/* vim:ts=4:sts=4:sw=4:
 * ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Ajax.org Code Editor (ACE).
 *
 * The Initial Developer of the Original Code is
 * Ajax.org B.V.
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *      Fabian Jakobs <fabian AT ajax DOT org>
 *      Julian Viereck <julian.viereck@gmail.com>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

define(function(require, exports, module) {
"use strict";

var dom = require("../lib/dom");

var Cursor = function(parentEl) {
    this.element = dom.createElement("div");
    this.element.className = "ace_layer ace_cursor-layer";
    parentEl.appendChild(this.element);

    this.isVisible = false;

    this.cursors = [];
    this.cursor = this.addCursor();
};

(function() {

    this.$padding = 0;
    this.setPadding = function(padding) {
        this.$padding = padding;
    };

    this.setSession = function(session) {
        this.session = session;
    };

    this.addCursor = function() {
        var el = dom.createElement("div");
        var className = "ace_cursor";
        if (!this.isVisible)
            className += " ace_hidden";
        if (this.overwrite)
            className += " ace_overwrite";

        el.className = className;
        this.element.appendChild(el);
        this.cursors.push(el);
        return el;
    };

    this.removeCursor = function() {
        if (this.cursors.length > 1) {
            var el = this.cursors.pop();
            el.parentNode.removeChild(el);
            return el;
        }
    };

    this.hideCursor = function() {
        this.isVisible = false;
        for (var i = this.cursors.length; i--; )
            dom.addCssClass(this.cursors[i], "ace_hidden");
        clearInterval(this.blinkId);
    };

    this.showCursor = function() {
        this.isVisible = true;
        for (var i = this.cursors.length; i--; )
            dom.removeCssClass(this.cursors[i], "ace_hidden");

        this.element.style.visibility = "";
        this.restartTimer();
    };

    this.restartTimer = function() {
        clearInterval(this.blinkId);
        if (!this.isVisible)
            return;

        var element = this.cursors.length == 1 ? this.cursor : this.element;
        this.blinkId = setInterval(function() {
            element.style.visibility = "hidden";
            setTimeout(function() {
                element.style.visibility = "";
            }, 400);
        }, 1000);
    };

    this.getPixelPosition = function(position, onScreen) {
        if (!this.config || !this.session) {
            return {
                left : 0,
                top : 0
            };
        }

        if (!position)
            position = this.session.selection.getCursor();
        var pos = this.session.documentToScreenPosition(position);
        var cursorLeft = Math.round(this.$padding +
                                    pos.column * this.config.characterWidth);
        var cursorTop = (pos.row - (onScreen ? this.config.firstRowScreen : 0)) *
            this.config.lineHeight;

        return {
            left : cursorLeft,
            top : cursorTop
        };
    };

    this.update = function(config) {
        this.config = config;

        if (this.session.selectionMarkerCount > 0) {
            var selections = this.session.$selectionMarkers;
            var i = 0, sel, cursorIndex = 0;

            for (var i = selections.length; i--; ) {
                sel = selections[i];
                var pixelPos = this.getPixelPosition(sel.cursor, true);

                var style = (this.cursors[cursorIndex++] || this.addCursor()).style;

                style.left = pixelPos.left + "px";
                style.top = pixelPos.top + "px";
                style.width = config.characterWidth + "px";
                style.height = config.lineHeight + "px";
            }
            if (cursorIndex > 1)
                while (this.cursors.length > cursorIndex)
                    this.removeCursor();
        } else {
            var pixelPos = this.getPixelPosition(null, true);
            var style = this.cursor.style;
            style.left = pixelPos.left + "px";
            style.top = pixelPos.top + "px";
            style.width = config.characterWidth + "px";
            style.height = config.lineHeight + "px";

            while (this.cursors.length > 1)
                this.removeCursor();
        }

        var overwrite = this.session.getOverwrite();
        if (overwrite != this.overwrite)
            this.$setOverite(overwrite);

        this.restartTimer();
    };

    this.$setOverite = function(overwrite) {
        this.overwrite = overwrite;
        for (var i = this.cursors.length; i--; ) {
            if (overwrite)
                dom.addCssClass(this.cursors[i], "ace_overwrite");
            else
                dom.removeCssClass(this.cursors[i], "ace_overwrite");
        }
    };

    this.destroy = function() {
        clearInterval(this.blinkId);
    }

}).call(Cursor.prototype);

exports.Cursor = Cursor;

});