"use strict";

const Common = (function(){

    const Common = function(){};

    Common.get_keys = (...items) => items.reduce((keys, item) => {

        if(item){
            if(typeof item == "string" && /^[a-z_][a-z0-9_]*$/i.test(item) && !keys.includes(item))
                keys.push(item);
            else if(item instanceof Array)
                for(const key of Common.get_keys(...item))
                    keys.includes(item) || keys.push(key);
        };

        return keys;
    }, []);

    Common.get_dictionaries = (...items) => items.reduce((dictionaries, item) => {

        if(item){
            if(item.constructor == Object)
                dictionaries.push(item);
            else if(item instanceof Array)
                dictionaries.push(...Common.get_dictionaries(...item));
        };

        return dictionaries;
    }, []);

    Common.get_value = (keys, inputs, _default = null) => {
        if((keys = Common.get_keys(keys)).length)
            for(const subinputs of Common.get_dictionaries(inputs))
                for(const key of keys)
                    if(subinputs[key] !== undefined)
                        return subinputs[key];
        return _default;
    };

    Common.get_dictionary = (items, overwrite = false) => {

        if(items){
            if(items.constructor == Object)
                return items;
            else if(items instanceof Array)
                return items.reduce((dictionary, item) => {
                    Object.entries(Common.get_dictionary(item)).forEach(([key, value]) => {
                        if(overwrite || dictionary[key] === undefined)
                            dictionary[key] = value;
                    });
                    return dictionary;
                }, {});
        };

        return {};
    };

    Common.string_variables = (string, variables, _default = null) => {

        variables = Common.get_dictionary(variables);

        return ("" + string).replace(/\{([^\{\}]+)\}/g, (all, key) => (
            variables[key] !== undefined ? variables[key] : 
            _default !== null ? _default : 
        all));
    };

    Common.execute_array = (array, each_callback, end_callback, i = 0) => {
        if(i == array.length)
            end_callback();
        else 
            each_callback(array[i], () => {
                Common.execute_array(array, each_callback, end_callback, i + 1);
            });
    };

    Common.SCSS = (data, selector = "") => {
        
        /** @type {Arrya.<string>} */
        const childs = [];
        /** @type {string} */
        let css = ``;

        Object.entries(data).forEach(([key, value]) => {
            if(value && value.constructor == Object)
                key.split(",").forEach(key => {

                    /** @type {string} */
                    const subselector = `${(selector ? selector + (
                              key[0] == "&" ? "" : " "
                          ) : "") + (
                              key[0] == "&" ? key.substring(1) : key
                          )}`, 
                          /** @type {Array<string>} */
                          subcss = Common.SCSS(value, subselector);

                    childs.push(`\n\n${subselector}{${subcss[0]}\n}`, ...subcss.slice(1));

                });
            else 
                css += `\n    ${key.replace(/[^a-z0-9]+/gi, "-")} : ${value === null ? "none" : value};`;
        });

        if(!selector){

            /** @type {HTMLStyleElement} */
            let style = document.querySelector("head>style");
            
            if(!style){
                style = document.querySelector("head").appendChild(document.createElement("style"));
                [
                    ["data-type", "text/css;charset=utf-8"], 
                    ["data-language", "CSS3"],
                    ["charset", "utf-8"]
                ].forEach(([key, value]) => style.setAttribute(key, value === null ? "none" : value));
            };

            style.appendChild(document.createTextNode(css + childs.join("")));

        };

        return [css, ...childs];
    };

    return Common;
})();