"use strict";
var __spreadArray = (this && this.__spreadArray) || function (to, from, pack) {
    if (pack || arguments.length === 2) for (var i = 0, l = from.length, ar; i < l; i++) {
        if (ar || !(i in from)) {
            if (!ar) ar = Array.prototype.slice.call(from, 0, i);
            ar[i] = from[i];
        }
    }
    return to.concat(ar || Array.prototype.slice.call(from));
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.bemmy = void 0;
/**
 * Creates and returns a function to format CSS classes following the {@link http://getbem.com/naming|BEM Convention}
 * @param [block] - {@link https://getbem.com/naming/#Block:~:text=of%20the%20website.-,Block,-Encapsulates%20a%20standalone|Block name} (standalone entity that is meaningful on its own)
 * @returns {(element?: string, modifiers?: string | Array.<string> | object, ...additionalClasses?:string) => string} Function that accepts {@link https://getbem.com/naming/#Block:~:text=block%20%7B%20color%3A%20%23042%3B%20%7D-,Element,-Parts%20of%20a|element} / {@link https://getbem.com/naming/#Block:~:text=%23042%3B%20%7D-,Modifier,-Flags%20on%20blocks|modifier} name arguments
 * @example
 * ```ts
 * import bemmy from 'bemmy';
 * const bem = bemmy('component')
 *
 * // block
 * bem()
 * // -> 'component'
 *
 * // block + element
 * bem('content')
 * // -> 'component__content'
 *
 * // block + modifier
 * bem(null, 'disabled')
 * // -> 'component component--disabled'
 *
 * // block + element + modifier
 * bem('content', 'disabled')
 * // -> 'component__content component__content--disabled'
 *
 * // multiple modifiers (object or array)
 * bem('content', { tall: true, green: true })
 * // -> 'component__content component__content--tall component__content--green'
 * bem('content', ['tall', 'green'])
 * // -> 'component__content component__content--tall component__content--green'
 *
 * // dynamic modifiers
 * const props = {
 *   tall: false,
 *   green: undefined,
 *   wide: true
 *   custom: 1 > 2 // some expression that resolves to true or false
 * };
 * bem('content', props)
 * // -> 'component__content component__content--wide'
 *
 * // additional classes
 * bem(null, null, 'some-class', 'another-class')
 * // -> 'component some-class another-class'
 * ```
 */
var bemmy = function (block) {
    if (block === void 0) { block = ''; }
    return function (element, modifiers) {
        var additionalClasses = [];
        for (var _i = 2; _i < arguments.length; _i++) {
            additionalClasses[_i - 2] = arguments[_i];
        }
        var _element = element ? "__".concat(element) : '';
        var _modifiers = [];
        if (modifiers) {
            if (typeof modifiers === 'string') {
                _modifiers = [modifiers];
            }
            else if (Array.isArray(modifiers)) {
                _modifiers = modifiers.filter(isValidString);
            }
            else if (typeof modifiers === 'object' && !Array.isArray(modifiers)) {
                _modifiers = Object.keys(modifiers).filter(function (key) { return modifiers[key]; });
            }
        }
        var classArr = __spreadArray(__spreadArray([
            "".concat(block).concat(_element)
        ], _modifiers.reduce(function (acc, modifier) {
            acc.push("".concat(block).concat(_element, "--").concat(modifier));
            return acc;
        }, []), true), additionalClasses.filter(Boolean), true);
        return classArr.join(' ');
    };
};
exports.bemmy = bemmy;
function isValidString(val) {
    return typeof val === 'string' && val !== '';
}
exports.default = exports.bemmy;