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 * Distributed under the BSD license:
 *
 * Copyright (c) 2010, Ajax.org B.V.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
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 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in the
 *       documentation and/or other materials provided with the distribution.
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 *       names of its contributors may be used to endorse or promote products
 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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define(function (require, exports, module) {
    "use strict";

    var EditSession = require("../edit_session").EditSession;
    var TextLayer = require("../layer/text").Text;
    var baseStyles = require("../requirejs/text!./static.css");
    var config = require("../config");
    var dom = require("../lib/dom");

    var SimpleTextLayer = function () {
        this.config = {};
    };
    SimpleTextLayer.prototype = TextLayer.prototype;

    var highlight = function (el, opts, callback) {
        var m = el.className.match(/lang-(\w+)/);
        var mode = opts.mode || m && ("ace/mode/" + m[1]);
        if (!mode)
            return false;
        var theme = opts.theme || "ace/theme/textmate";

        var data = "";
        var nodes = [];

        if (el.firstElementChild) {
            var textLen = 0;
            for (var i = 0; i < el.childNodes.length; i++) {
                var ch = el.childNodes[i];
                if (ch.nodeType == 3) {
                    textLen += ch.data.length;
                    data += ch.data;
                } else {
                    nodes.push(textLen, ch);
                }
            }
        } else {
            data = dom.getInnerText(el);
            if (opts.trim)
                data = data.trim();
        }

        highlight.render(data, mode, theme, opts.firstLineNumber, !opts.showGutter, function (highlighted) {
            dom.importCssString(highlighted.css, "ace_highlight");
            el.innerHTML = highlighted.html;
            var container = el.firstChild.firstChild;
            for (var i = 0; i < nodes.length; i += 2) {
                var pos = highlighted.session.doc.indexToPosition(nodes[i]);
                var node = nodes[i + 1];
                var lineEl = container.children[pos.row];
                lineEl && lineEl.appendChild(node);
            }
            callback && callback();
        });
    };

    /**
     * Transforms a given input code snippet into HTML using the given mode
     *
     * @param {string} input Code snippet
     * @param {string|mode} mode String specifying the mode to load such as
     *  `ace/mode/javascript` or, a mode loaded from `/ace/mode`
     *  (use 'ServerSideHiglighter.getMode').
     * @param {string|theme} theme String specifying the theme to load such as
     *  `ace/theme/twilight` or, a theme loaded from `/ace/theme`.
     * @param {number} lineStart A number indicating the first line number. Defaults
     *  to 1.
     * @param {boolean} disableGutter Specifies whether or not to disable the gutter.
     *  `true` disables the gutter, `false` enables the gutter. Defaults to `false`.
     * @param {function} callback When specifying the mode or theme as a string,
     *  this method has no return value and you must specify a callback function. The
     *  callback will receive the rendered object containing the properties `html`
     *  and `css`.
     * @returns {object} An object containing the properties `html` and `css`.
     */
    highlight.render = function (input, mode, theme, lineStart, disableGutter, callback) {
        var waiting = 1;
        var modeCache = EditSession.prototype.$modes;

        // if either the theme or the mode were specified as objects
        // then we need to lazily load them.
        if (typeof theme == "string") {
            waiting++;
            config.loadModule(['theme', theme], function (m) {
                theme = m;
                --waiting || done();
            });
        }
        // allow setting mode options e.h {path: "ace/mode/php", inline:true}
        var modeOptions;
        if (mode && typeof mode === "object" && !mode.getTokenizer) {
            modeOptions = mode;
            mode = modeOptions.path;
        }
        if (typeof mode == "string") {
            waiting++;
            config.loadModule(['mode', mode], function (m) {
                if (!modeCache[mode] || modeOptions)
                    modeCache[mode] = new m.Mode(modeOptions);
                mode = modeCache[mode];
                --waiting || done();
            });
        }

        // loads or passes the specified mode module then calls renderer
        function done() {
            var result = highlight.renderSync(input, mode, theme, lineStart, disableGutter);
            return callback ? callback(result) : result;
        }

        return --waiting || done();
    };

    /**
     * Transforms a given input code snippet into HTML using the given mode
     * @param {string} input Code snippet
     * @param {mode} mode Mode loaded from /ace/mode (use 'ServerSideHiglighter.getMode')
     * @param {string} r Code snippet
     * @returns {object} An object containing: html, css
     */
    highlight.renderSync = function (input, mode, theme, lineStart, disableGutter) {
        lineStart = parseInt(lineStart || 1, 10);

        var session = new EditSession("");
        session.setUseWorker(false);
        session.setMode(mode);

        var textLayer = new SimpleTextLayer();
        textLayer.setSession(session);

        session.setValue(input);

        var stringBuilder = [];
        var length = session.getLength();

        for (var ix = 0; ix < length; ix++) {
            stringBuilder.push("<div class='ace_line'>");
            if (!disableGutter)
                stringBuilder.push("<span class='ace_gutter ace_gutter-cell' unselectable='on'>" + /*(ix + lineStart) + */ "</span>");
            textLayer.$renderLine(stringBuilder, ix, true, false);
            stringBuilder.push("\n</div>");
        }

        // let's prepare the whole html
        var html = "<div class='" + theme.cssClass + "'>" +
            "<div class='ace_static_highlight" + (disableGutter ? "" : " ace_show_gutter") +
            "' style='counter-reset:ace_line " + (lineStart - 1) + "'>" +
            stringBuilder.join("") +
            "</div>" +
            "</div>";

        textLayer.destroy();

        return {
            css: baseStyles + theme.cssText,
            html: html,
            session: session
        };
    };

    module.exports = highlight;
    module.exports.highlight = highlight;
});
