/**
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; under version 2
 * of the License (non-upgradable).
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 *
 * Copyright (c) 2013-2019 (original work) Open Assessment Technologies SA (under the project TAO-PRODUCT);
 *
 *
 */
/**
 * ORGINAL VERSION:
 * https://github.com/epeli/requirejs-hbs
 * Copyright 2013 Esa-Matti Suuronen
 * MIT License : https://github.com/epeli/requirejs-hbs/blob/master/LICENSE
 *
 * MODIFIED VERSION:
 * @author Bertrand Chevrier <bertrand@taotesting.com> for OAT SA
 * - Minor code refactoring
 * - i18n helper has been added
 * - dompurify helper has been added
 */
define([
    'handlebars',
    'i18n',
    'lodash',
    'lib/dompurify/purify'
], function(hb, __, _, DOMPurify){
    'use strict';

    var buildMap = {};
    var extension = '.tpl';

    //register a i18n helper
    hb.registerHelper('__', function(key){
        return __(key);
    });

    /**
     * Register dompurify helper
     *
     * https://github.com/cure53/DOMPurify
     * with config SAFE_FOR_TEMPLATES: true
     * to make output safe for template systems
     */
    hb.registerHelper('dompurify', function(context){
        return DOMPurify.sanitize(context);
    });

    /**
     * Register join helper
     *
     * Example :
     * var values = {a:v1, b:v2, c:v3};
     * Using {{{join attributes '=' ' ' '"'}}} will return : a="v1" b="v2" c="v3"
     * Using {{{join values null ' or ' '*'}}} will return : *v1* or *v2* or *v3*
     */
    hb.registerHelper('join', function(arr, keyValueGlue, fragmentGlue, wrapper){

        var fragments = [];

        keyValueGlue = typeof(keyValueGlue) === 'string' ? keyValueGlue : undefined;
        fragmentGlue = typeof(fragmentGlue) === 'string' ? fragmentGlue : ' ';
        wrapper = typeof(wrapper) === 'string' ? wrapper : '"';

        _.forIn(arr, function(value, key){
            var fragment = '';
            if(value !== null || value !== undefined){
                if(typeof(value) === 'boolean'){
                    value = value ? 'true' : 'false';
                }else if(typeof(value) === 'object'){
                    value = _.values(value).join(' ');
                }
            }else{
                value = '';
            }
            if(keyValueGlue !== undefined){
                fragment += key + keyValueGlue;
            }
            fragment += wrapper + value + wrapper;
            fragments.push(fragment);
        });

        return fragments.join(fragmentGlue);
    });

    //register a classic "for loop" helper
    //it also adds a local variable "i" as the index in each iteration loop
    hb.registerHelper('for', function(startIndex, stopIndex, increment, options){
        var ret = '';
        startIndex = parseInt(startIndex);
        stopIndex = parseInt(stopIndex);
        increment = parseInt(increment);

        for(var i = startIndex; i < stopIndex; i += increment){
            ret += options.fn(_.extend({}, this, {'i' : i}));
        }

        return ret;
    });

    hb.registerHelper('equal', function(var1, var2, options){
        if(var1 == var2){
            return options.fn(this);
        }else{
            return options.inverse(this);
        }
    });

    // register a "get property" helper
    // it gets the named property from the provided context
    hb.registerHelper('property', function(name, context){
        return (typeof (context[name]) !== "undefined") ? new hb.SafeString(context[name]) : '';
    });

    // register an 'includes' helper
    // it checks if value is in array
    hb.registerHelper('includes', function (haystack, needle, options) {
        if (_.contains(haystack, needle)) {
            return options.fn(this);
        }
    });

    return {
        load : function(name, req, onload, config){
            extension = extension || config.extension;

            if(config.isBuild){
                //optimization, r.js node.js version
                buildMap[name] = fs.readFileSync(req.toUrl(name + extension)).toString().trim();
                onload();

            } else {
                req(["text!" + name + extension], function(raw){
                    // Just return the compiled template
                    onload(function(){
                        var compiled = hb.compile(raw);
                        return compiled.apply(hb, arguments).trim();
                    });
                });
            }
        },
        write : function(pluginName, moduleName, write){
            var compiled;
            if(moduleName in buildMap){
                compiled = hb.precompile(buildMap[moduleName]);
                // Write out precompiled version of the template function as AMD definition.
                write(
                    "define('tpl!" + moduleName + "', ['handlebars'], function(hb){ \n" +
                    "return hb.template(" + compiled.toString() + ");\n" +
                    "});\n"
                );
            }
        }
    };
});