let objectValues = require('lodash').values;

/**
 * Generic tap function.
 *
 * @param {*}    val
 * @param {Function} callback
 */
global.tap = function (val, callback) {
    callback(val);

    return val;
};

/**
 * Add tap to arrays.
 *
 * @param {*}    val
 * @param {Function} callback
 */
Object.defineProperty(Array.prototype, 'tap', {
    value: function (callback) {
        if (this.length) {
            callback(this);
        }

        return this;
    }
});

/**
 * Add wrap to arrays.
 *
 * @param {*}    val
 * @param {Function} callback
 */
Object.defineProperty(Array, 'wrap', {
    value(value) {
        if (Array.isArray(value)) {
            return value;
        }

        return [value];
    }
});

/**
 * Flatten the given array.
 *
 * @param {Array} arr
 */
global.flatten = function (arr) {
    return [].concat.apply([], objectValues(arr));
};