/* $Id: array.js,v 1.1 2019/07/22 20:51:52 echicken Exp $ */
/**
 * Polyfills for newer Array methods
 * Lifted from MDN https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array
 *
 * This is a legacy-style library and should be loaded with:
 * load('array.js');
 */

if (!Array.from) {
	Array.from = (function () {
		var toStr = Object.prototype.toString;
		var isCallable = function (fn) {
			return (
				typeof fn === 'function' ||
				toStr.call(fn) === '[object Function]'
			);
		};
		var toInteger = function (value) {
			var number = Number(value);
			if (isNaN(number)) return 0;
			if (number === 0 || !isFinite(number)) return number;
			return (number > 0 ? 1 : -1) * Math.floor(Math.abs(number));
		};
		var maxSafeInteger = Math.pow(2, 53) - 1;
		var toLength = function (value) {
			var len = toInteger(value);
			return Math.min(Math.max(len, 0), maxSafeInteger);
		};

		// The length property of the from method is 1.
		return function from(arrayLike /*, mapFn, thisArg */) {
			// 1. Let C be the this value.
			var C = this;

			// 2. Let items be ToObject(arrayLike).
			var items = Object(arrayLike);

			// 3. ReturnIfAbrupt(items).
			if (arrayLike == null) {
				throw new TypeError(
					'Array.from requires an array-like object - not null or undefined'
				);
			}

			// 4. If mapfn is undefined, then let mapping be false.
			var mapFn = arguments.length > 1 ? arguments[1] : void undefined;
			var T;
			if (typeof mapFn !== 'undefined') {
				// 5. else
				// 5. a If IsCallable(mapfn) is false, throw a TypeError exception.
				if (!isCallable(mapFn)) {
					throw new TypeError(
						'Array.from: when provided, the second argument must be a function'
					);
				}

				// 5. b. If thisArg was supplied, let T be thisArg; else let T be undefined.
				if (arguments.length > 2) T = arguments[2];
			}

			// 10. Let lenValue be Get(items, "length").
			// 11. Let len be ToLength(lenValue).
			var len = toLength(items.length);

			// 13. If IsConstructor(C) is true, then
			// 13. a. Let A be the result of calling the [[Construct]] internal method
			// of C with an argument list containing the single item len.
			// 14. a. Else, Let A be ArrayCreate(len).
			var A = isCallable(C) ? Object(new C(len)) : new Array(len);

			// 16. Let k be 0.
			var k = 0;
			// 17. Repeat, while k < len… (also steps a - h)
			var kValue;
			while (k < len) {
				kValue = items[k];
				if (mapFn) {
					A[k] =
						typeof T === 'undefined'
							? mapFn(kValue, k)
							: mapFn.call(T, kValue, k);
				} else {
					A[k] = kValue;
				}
				k += 1;
			}
			// 18. Let putStatus be Put(A, "length", len, true).
			A.length = len;
			// 20. Return A.
			return A;
		};
	})();
}

if (!Array.of) {
	Array.of = function () {
		return Array.prototype.slice.call(arguments);
	};
}

if (!Array.prototype.copyWithin) {
	Object.defineProperty(Array.prototype, 'copyWithin', {
		value: function (target, start /*, end*/) {
			// Steps 1-2.
			if (this == null) {
				throw new TypeError('this is null or not defined');
			}

			var O = Object(this);

			// Steps 3-5.
			var len = O.length >>> 0;

			// Steps 6-8.
			var relativeTarget = target >> 0;

			var to =
				relativeTarget < 0
					? Math.max(len + relativeTarget, 0)
					: Math.min(relativeTarget, len);

			// Steps 9-11.
			var relativeStart = start >> 0;

			var from =
				relativeStart < 0
					? Math.max(len + relativeStart, 0)
					: Math.min(relativeStart, len);

			// Steps 12-14.
			var end = arguments[2];
			var relativeEnd = end === undefined ? len : end >> 0;

			var final =
				relativeEnd < 0
					? Math.max(len + relativeEnd, 0)
					: Math.min(relativeEnd, len);

			// Step 15.
			var count = Math.min(final - from, len - to);

			// Steps 16-17.
			var direction = 1;

			if (from < to && to < from + count) {
				direction = -1;
				from += count - 1;
				to += count - 1;
			}

			// Step 18.
			while (count > 0) {
				if (from in O) {
					O[to] = O[from];
				} else {
					delete O[to];
				}
				from += direction;
				to += direction;
				count--;
			}

			// Step 19.
			return O;
		},
		configurable: true,
		writable: true,
	});
}

if (!Array.prototype.fill) {
	Object.defineProperty(Array.prototype, 'fill', {
		value: function (value) {
			// Steps 1-2.
			if (this == null)
				throw new TypeError('this is null or not defined');

			var O = Object(this);

			// Steps 3-5.
			var len = O.length >>> 0;

			// Steps 6-7.
			var start = arguments[1];
			var relativeStart = start >> 0;

			// Step 8.
			var k =
				relativeStart < 0
					? Math.max(len + relativeStart, 0)
					: Math.min(relativeStart, len);

			// Steps 9-10.
			var end = arguments[2];
			var relativeEnd = end === undefined ? len : end >> 0;

			// Step 11.
			var final =
				relativeEnd < 0
					? Math.max(len + relativeEnd, 0)
					: Math.min(relativeEnd, len);

			// Step 12.
			while (k < final) {
				O[k] = value;
				k++;
			}

			// Step 13.
			return O;
		},
	});
}

// https://tc39.github.io/ecma262/#sec-array.prototype.find
if (!Array.prototype.find) {
	Object.defineProperty(Array.prototype, 'find', {
		value: function (predicate) {
			// 1. Let O be ? ToObject(this value).
			if (this == null) {
				throw new TypeError('"this" is null or not defined');
			}

			var o = Object(this);

			// 2. Let len be ? ToLength(? Get(O, "length")).
			var len = o.length >>> 0;

			// 3. If IsCallable(predicate) is false, throw a TypeError exception.
			if (typeof predicate !== 'function') {
				throw new TypeError('predicate must be a function');
			}

			// 4. If thisArg was supplied, let T be thisArg; else let T be undefined.
			var thisArg = arguments[1];

			// 5. Let k be 0.
			var k = 0;

			// 6. Repeat, while k < len
			while (k < len) {
				// a. Let Pk be ! ToString(k).
				// b. Let kValue be ? Get(O, Pk).
				// c. Let testResult be ToBoolean(? Call(predicate, T, « kValue, k, O »)).
				// d. If testResult is true, return kValue.
				var kValue = o[k];
				if (predicate.call(thisArg, kValue, k, o)) return kValue;
				// e. Increase k by 1.
				k++;
			}

			// 7. Return undefined.
			return undefined;
		},
		configurable: true,
		writable: true,
	});
}

// https://tc39.github.io/ecma262/#sec-array.prototype.findindex
if (!Array.prototype.findIndex) {
	Object.defineProperty(Array.prototype, 'findIndex', {
		value: function (predicate) {
			// 1. Let O be ? ToObject(this value).
			if (this == null) {
				throw new TypeError('"this" is null or not defined');
			}

			var o = Object(this);

			// 2. Let len be ? ToLength(? Get(O, "length")).
			var len = o.length >>> 0;

			// 3. If IsCallable(predicate) is false, throw a TypeError exception.
			if (typeof predicate !== 'function') {
				throw new TypeError('predicate must be a function');
			}

			// 4. If thisArg was supplied, let T be thisArg; else let T be undefined.
			var thisArg = arguments[1];

			// 5. Let k be 0.
			var k = 0;

			// 6. Repeat, while k < len
			while (k < len) {
				// a. Let Pk be ! ToString(k).
				// b. Let kValue be ? Get(O, Pk).
				// c. Let testResult be ToBoolean(? Call(predicate, T, « kValue, k, O »)).
				// d. If testResult is true, return k.
				var kValue = o[k];
				if (predicate.call(thisArg, kValue, k, o)) return k;
				// e. Increase k by 1.
				k++;
			}

			// 7. Return -1.
			return -1;
		},
		configurable: true,
		writable: true,
	});
}

// From https://github.com/latusinski/polyfill-array-includes/blob/master/array-includes.js
if (!Array.prototype.includes) {
	Object.defineProperty(Array.prototype, 'includes', {
		value: function (searchElement, fromIndex) {
			// 1. Let O be ? ToObject(this value).
			if (this == null)
				throw new TypeError('"this" is null or not defined');

			var o = Object(this);

			// 2. Let len be ? ToLength(? Get(O, "length")).
			var len = o.length >>> 0;

			// 3. If len is 0, return false.
			if (len === 0) return false;

			// 4. Let n be ? ToInteger(fromIndex).
			//    (If fromIndex is undefined, this step produces the value 0.)
			var n = fromIndex | 0;

			// 5. If n ≥ 0, then
			//  a. Let k be n.
			// 6. Else n < 0,
			//  a. Let k be len + n.
			//  b. If k < 0, let k be 0.
			var k = Math.max(n >= 0 ? n : len - Math.abs(n), 0);

			function sameValueZero(x, y) {
				return (
					x === y ||
					(typeof x === 'number' &&
						typeof y === 'number' &&
						isNaN(x) &&
						isNaN(y))
				);
			}

			// 7. Repeat, while k < len
			while (k < len) {
				// a. Let elementK be the result of ? Get(O, ! ToString(k)).
				// b. If SameValueZero(searchElement, elementK) is true, return true.
				// c. Increase k by 1.
				if (sameValueZero(o[k], searchElement)) return true;
				k++;
			}

			// 8. Return false
			return false;
		},
	});
}
