class ArrayUtils {
    /**
     * 执行冒泡排序
     * @param ary
     */
    public static bubbleSort(ary: number[]): void {
        let isExchange: Boolean = false;
        for (let i: number = 0; i < ary.length; i++) {
            isExchange = false;
            for (let j: number = ary.length - 1; j > i; j--) {
                if (ary[j] < ary[j - 1]) {
                    let temp: number = ary[j];
                    ary[j] = ary[j - 1];
                    ary[j - 1] = temp;
                    isExchange = true;
                }
            }
            if (!isExchange)
                break;
        }
    }

    /**
     * 执行插入排序
     * @param ary 
     */
    public static insertionSort(ary: number[]): void {
        let len: number = ary.length;
        for (let i: number = 1; i < len; i++) {
            let val: number = ary[i];
            for (var j: number = i; j > 0 && ary[j - 1] > val; j--) {
                ary[j] = ary[j - 1];
            }
            ary[j] = val;
        }
    }

    /**
     * 执行二分搜索
     * @param ary 搜索的数组（必须排序过）
     * @param value 需要搜索的值
     * @returns 返回匹配结果的数组索引
     */
    public static binarySearch(ary: number[], value: number): number {
        let startIndex: number = 0;
        let endIndex: number = ary.length;
        let sub: number = (startIndex + endIndex) >> 1;
        while (startIndex < endIndex) {
            if (value <= ary[sub]) endIndex = sub;
            else if (value >= ary[sub]) startIndex = sub + 1;
            sub = (startIndex + endIndex) >> 1;
        }
        if (ary[startIndex] == value) return startIndex;
        return -1;
    }


    /**
     * 返回匹配项的索引
     * @param ary 
     * @param num 
     */
    public static findElementIndex(ary: any[], num: any): any {
        let len: number = ary.length;
        for (let i: number = 0; i < len; ++i) {
            if (ary[i] == num)
                return i;
        }
        return null;
    }

    /**
     * 返回数组中最大值的索引
     * @param ary 
     */
    public static getMaxElementIndex(ary: number[]): number {
        let matchIndex: number = 0;
        let len: number = ary.length;
        for (let j: number = 1; j < len; j++) {
            if (ary[j] > ary[matchIndex])
                matchIndex = j;
        }
        return matchIndex;
    }

    /**
     * 返回数组中最小值的索引
     * @param ary 
     */
    public static getMinElementIndex(ary: number[]): number {
        let matchIndex: number = 0;
        let len: number = ary.length;
        for (let j: number = 1; j < len; j++) {
            if (ary[j] < ary[matchIndex])
                matchIndex = j;
        }
        return matchIndex;
    }

    /**
     * 返回一个"唯一性"数组
     * @param ary 需要唯一性的数组
     * @returns 唯一性的数组
     * 
     * @tutorial
     * 比如: [1, 2, 2, 3, 4]
     * 返回: [1, 2, 3, 4]
     */
    public static getUniqueAry(ary: number[]): number[] {
        let uAry: number[] = [];
        let newAry: number[] = [];
        let count = ary.length;
        for (let i: number = 0; i < count; ++i) {
            let value: number = ary[i];
            if (uAry.indexOf(value) == -1) uAry.push(value);
        }

        count = uAry.length;
        for (let i: number = count - 1; i >= 0; --i) {
            newAry.unshift(uAry[i]);
        }
        return newAry;
    }


    /**
     * 返回2个数组中不同的部分
     * 比如数组A = [1, 2, 3, 4, 6]
     *    数组B = [0, 2, 1, 3, 4]
     * 返回[6, 0]
     * @param    aryA
     * @param    aryB
     * @return
     */
    public static getDifferAry(aryA: number[], aryB: number[]): number[] {
        aryA = this.getUniqueAry(aryA);
        aryB = this.getUniqueAry(aryB);
        let ary: number[] = aryA.concat(aryB);
        let uObj: Object = {};
        let newAry: number[] = [];
        let count: number = ary.length;
        for (let j: number = 0; j < count; ++j) {
            if (!uObj[ary[j]]) {
                uObj[ary[j]] = {};
                uObj[ary[j]].count = 0;
                uObj[ary[j]].key = ary[j];
                uObj[ary[j]].count++;
            } else {
                if (uObj[ary[j]] instanceof Object) {
                    uObj[ary[j]].count++;
                }
            }
        }
        for (let i in uObj) {
            if (uObj[i].count != 2) {
                newAry.unshift(uObj[i].key);
            }
        }
        return newAry;
    }

    /**
     * 交换数组元素
     * @param    array    目标数组
     * @param    index1    交换后的索引
     * @param    index2    交换前的索引
     */
    public static swap(array: any[], index1: number, index2: number): void {
        let temp: any = array[index1];
        array[index1] = array[index2];
        array[index2] = temp;
    }


    /**
     * 清除列表
     * @param ary 
     */
    public static clearList(ary: any[]): void {
        if (!ary) return;
        let length: number = ary.length;
        for (let i: number = length - 1; i >= 0; i -= 1) {
            ary.splice(i, 1);
        }
    }

    /**
     * 克隆一个数组
     * @param    ary 需要克隆的数组
     * @return  克隆的数组
     */
    public static cloneList(ary: any[]): any[] {
        if (!ary) return null;
        return ary.slice(0, ary.length);
    }

    /**
     * 判断2个数组是否相同
     * @param ary1 数组1
     * @param ary2 数组2
     */
    public static equals(ary1: number[], ary2: number[]): Boolean {
        if (ary1 == ary2) return true;
        let length: number = ary1.length;
        if (length != ary2.length) return false;
        while (length--) {
            if (ary1[length] != ary2[length])
                return false;
        }
        return true;
    }

    /**
     * 根据索引插入元素，索引和索引后的元素都向后移动一位
     * @param ary
     * @param index 插入索引
     * @param value 插入的元素
     * @returns 插入的元素 未插入则返回空
     */
    public static insert(ary: any[], index: number, value: any): any {
        if (!ary) return null;
        let length: number = ary.length;
        if (index > length) index = length;
        if (index < 0) index = 0;
        if (index == length) ary.push(value); //插入最后
        else if (index == 0) ary.unshift(value); //插入头
        else {
            for (let i: number = length - 1; i >= index; i -= 1) {
                ary[i + 1] = ary[i];
            }
            ary[index] = value;
        }
        return value;
    }

    /**
     * 打乱数组 Fisher–Yates shuffle
     * @param list 
     */
    public static shuffle<T>(list: T[]) {
        let n = list.length;
        while (n > 1) {
            n--;
            let k = RandomUtils.randint(0, n + 1);
            let value: T = list[k];
            list[k] = list[n];
            list[n] = value;
        }
    }

    /**
     * 如果项目已经在列表中，返回false，如果成功添加，返回true
     * @param list 
     * @param item 
     */
    public static addIfNotPresent<T>(list: T[], item: T) {
        if (new linq.List(list).contains(item))
            return false;

        list.push(item);
        return true;
    }

    /**
     * 返回列表中的最后一项。列表中至少应该有一个项目
     * @param list 
     */
    public static lastItem<T>(list: T[]) {
        return list[list.length - 1];
    }

    /**
     * 从列表中随机获取一个项目。不清空检查列表!
     * @param list 
     */
    public static randomItem<T>(list: T[]) {
        return list[RandomUtils.randint(0, list.length - 1)];
    }

    /**
     * 从列表中随机获取物品。不清空检查列表，也不验证列表数是否大于项目数。返回的List可以通过ListPool.free放回池中
     * @param list 
     * @param itemCount 从列表中返回的随机项目的数量
     */
    public static randomItems<T>(list: T[], itemCount: number){
        let set = new Set<T>();
        while (set.size != itemCount) {
            let item = this.randomItem(list);
            if (!set.has(item))
                set.add(item);
        }

        let items = es.ListPool.obtain<T>();
        set.forEach(value => items.push(value));
        return items;
    }
}