enb/exlib/bemjson2bemdecl.js

Faster BEM/BEViS assembler

/**
 * --- (C) Original BEM Tools
 *
 * Инструментарий для преобразования bemjson в bemdecl.
 * Заимствованный.
 */

/**
 * Добавляет второй депс в первый и возвращает результат.
 * @param {Array} d1
 * @param {Array} d2
 * @returns {Array}
 */
function mergeDecls(d1, d2) {
    var keys = {};
    d1 ?
        d1.forEach(function (o) { keys[o.name || o] = o; }) :
        d1 = [];

    d2.forEach(function (o2) {
        var name = o2.name || o2;
        if (keys.hasOwnProperty(name)) {
            var o1 = keys[name];
            o2.elems && (o1.elems = mergeDecls(o1.elems, o2.elems));
            o2.mods && (o1.mods = mergeDecls(o1.mods, o2.mods));
            o2.vals && (o1.vals = mergeDecls(o1.vals, o2.vals));
            o2.techs && (o1.techs = mergeDecls(o1.techs, o2.techs));
        } else {
            d1.push(o2);
            keys[name] = o2;
        }
    });

    return d1;
}

/**
 * Возвращает true, если переданное значение имеет примитивный тип.
 * @param {*} obj
 * @returns {Boolean}
 */
function isSimple(obj) {
    var t = typeof obj;
    return t === 'string' || t === 'number' || t === 'boolean';
}

/**
 * Основная функция для преобразования в bemjson.
 * @param {Object} obj
 * @param {Function} fn
 * @returns {Object}
 */
function iterateJson(obj, fn) {
    if (obj && !isSimple(obj)) {
        if (Array.isArray(obj)) {
            var i = 0;
            var l = obj.length;
            while (i < l) {
                iterateJson(obj[i++], fn);
            }
        } else {
            fn(obj);
        }
    }
    return obj;
}

function getBuilder(decl, block) {
    return function (obj) {
        var oldBlock = block;
        block = obj.block || block;
        obj.block && decl.push({ name: block });
        obj.elem && decl.push({ name: block, elems: [{ name: obj.elem }] });
        var mods;
        var n;
        var props;
        if (mods = obj.mods) {
            for (n in mods) {
                if (mods.hasOwnProperty(n)) {
                    decl.push({
                        name: block,
                        mods: [{ name: n, vals: [ { name: mods[n] } ] }]
                    });
                }
            }
        }
        if (obj.elem && (mods = obj.elemMods)) {
            for (n in mods) {
                if (mods.hasOwnProperty(n)) {
                    decl.push({
                        name: block,
                        elems: [{
                            name: obj.elem,
                            mods: [{ name: n, vals: [ { name: mods[n] } ] }]
                        }]
                    });
                }
            }
        }
        props = Object.keys(obj).filter(function (k) {
                return !({ block: 1, elem: 1, mods: 1, elemMods: 1 }).hasOwnProperty(k);
            }).map(function (k) {
                return obj[k];
            });
        iterateJson(props, getBuilder(decl, block));
        block = oldBlock;
    }
}

module.exports.iterateJson = iterateJson;
module.exports.getBuilder = getBuilder;
module.exports.mergeDecls = mergeDecls;