//
// The following code was extracted from the `dequal` package
// * GitHub: https://github.com/lukeed/dequal
// * npm: https://www.npmjs.com/package/dequal
// * License: MIT
//

var has = Object.prototype.hasOwnProperty;

function find(iter: Array<any>, tar: any) {
    for (let key of iter.keys()) {
        if (dequal(key, tar)) {
            return key;
        }
    }
}

export function dequal(foo: any, bar: any) {
    var ctor, len, tmp;
    if (foo === bar) {
        return true;
    }

    if (foo && bar && (ctor = foo.constructor) === bar.constructor) {
        if (ctor === Date) {
            return foo.getTime() === bar.getTime();
        }
        if (ctor === RegExp) {
            return foo.toString() === bar.toString();
        }

        if (ctor === Array) {
            if ((len = foo.length) === bar.length) {
                while (len-- && dequal(foo[len], bar[len])) {

                }
            }
            return len === -1;
        }

        if (ctor === Set) {
            if (foo.size !== bar.size) {
                return false;
            }
            for (len of foo) {
                tmp = len;
                if (tmp && typeof tmp === 'object') {
                    tmp = find(bar, tmp);
                    if (!tmp) {
                        return false;
                    }
                }
                if (!bar.has(tmp)) {
                    return false;
                }
            }
            return true;
        }

        if (ctor === Map) {
            if (foo.size !== bar.size) {
                return false;
            }
            for (len of foo) {
                tmp = len[0];
                if (tmp && typeof tmp === 'object') {
                    tmp = find(bar, tmp);
                    if (!tmp) {
                        return false;
                    }
                }
                if (!dequal(len[1], bar.get(tmp))) {
                    return false;
                }
            }
            return true;
        }

        if (ctor === ArrayBuffer) {
            foo = new Uint8Array(foo);
            bar = new Uint8Array(bar);
        } else {
            if (ctor === DataView) {
                if ((len = foo.byteLength) === bar.byteLength) {
                    while (len-- && foo.getInt8(len) === bar.getInt8(len)) {

                    }
                }
                return len === -1;
            }
        }

        if (ArrayBuffer.isView(foo)) {
            if ((len = foo.byteLength) === bar.byteLength) {
                while (len-- && (foo as any)[len] === bar[len]) {

                }
            }
            return len === -1;
        }

        if (!ctor || typeof foo === 'object') {
            len = 0;
            for (ctor in foo) {
                if (has.call(foo, ctor) && ++len && !has.call(bar, ctor)) {
                    return false;
                }
                if (!(ctor in bar) || !dequal(foo[ctor], bar[ctor])) {
                    return false;
                }
            }
            return Object.keys(bar).length === len;
        }
    }

    return foo !== foo && bar !== bar;
}