/** 字符串工具 */
export class StringUtil {
    /** 获取一个唯一标识的字符串 */
    static guid() {
        let guid = '';
        for (let i = 1; i <= 32; i++) {
            const n = Math.floor(Math.random() * 16.0).toString(16);
            guid += n;
            if ((i == 8) || (i == 12) || (i == 16) || (i == 20))
                guid += '-';
        }
        return guid;
    }

    /**
     * 转美式计数字符串
     * @param value 数字
     * @example
     * 123456789 = 123,456,789
     */
    static numberTotPermil(value: number): string {
        return value.toLocaleString();
    }

    /**
     * 转英文单位计数
     * @param value 数字
     * @param fixed 保留小数位数
     * @example
     * 12345 = 12.35K
     */
    static numberToThousand(value: number, fixed = 2): string {
        const k = 1000;
        const sizes = ['', 'K', 'M', 'G'];
        if (value < k) {
            return value.toString();
        }
        else {
            const i = Math.floor(Math.log(value) / Math.log(k));
            const r = ((value / Math.pow(k, i)));
            return r.toFixed(fixed) + sizes[i];
        }
    }

    /**
     * 转中文单位计数
     * @param value 数字
     * @param fixed 保留小数位数
     * @example
     * 12345 = 1.23万
     */
    static numberToTenThousand(value: number, fixed = 2): string {
        const k = 10000;
        const sizes = ['', '万', '亿', '万亿'];
        if (value < k) {
            return value.toString();
        }
        else {
            const i = Math.floor(Math.log(value) / Math.log(k));
            return ((value / Math.pow(k, i))).toFixed(fixed) + sizes[i];
        }
    }

    /**
     * "," 分割字符串成数组
     * @param str 字符串
     */
    static stringToArray1(str: string) {
        if (str == '') {
            return [];
        }
        return str.split(',');
    }

    /**
     * "|" 分割字符串成数组
     * @param str 字符串
     */
    static stringToArray2(str: string) {
        if (str == '') {
            return [];
        }
        return str.split('|');
    }

    /**
     * ":" 分割字符串成数组
     * @param str 字符串
     */
    static stringToArray3(str: string) {
        if (str == '') {
            return [];
        }
        return str.split(':');
    }

    /**
     * ";" 分割字符串成数组
     * @param str 字符串
     */
    static stringToArray4(str: string) {
        if (str == '') {
            return [];
        }
        return str.split(';');
    }

    /**
     * 字符串截取
     * @param str     字符串
     * @param n       截取长度
     * @param showdot 是否把截取的部分用省略号代替
     */
    static sub(str: string, n: number, showdot = false) {
        const r = /[^\x00-\xff]/g;
        if (str.replace(r, 'mm').length <= n) {
            return str;
        }
        const m = Math.floor(n / 2);
        for (let i = m; i < str.length; i++) {
            if (str.substr(0, i).replace(r, 'mm').length >= n) {
                if (showdot) {
                    return str.substr(0, i) + '...';
                }
                else {
                    return str.substr(0, i);
                }
            }
        }
        return str;
    }

    /**
     * 计算字符串长度，中文算两个字节
     * @param str 字符串
     */
    static stringLen(str: string) {
        let realLength = 0, len = str.length, charCode = -1;
        for (let i = 0; i < len; i++) {
            charCode = str.charCodeAt(i);
            if (charCode >= 0 && charCode <= 128)
                realLength += 1;
            else
                realLength += 2;
        }
        return realLength;
    }

    /**
     * 是否为空
     * @param str 字符串
     */
    static isEmpty(str: string): boolean {
        return str == null || str == undefined || str.length == 0;
    }

    /**
     * 参数替换
     * @param  str  字符串
     * @param  rest 参数
     *
     * @example
     *
     * var str:string = "here is some info '{0}' and {1}";
     * StringUtil.substitute(str, 15.4, true);
     *
     * "here is some info '15.4' and true"
     */
    static substitute(str: string, ...rest: any[]): string {
        if (str == null) return '';

        let len: number = rest.length;
        let args: any[];
        if (len == 1 && rest[0] instanceof Array) {
            args = rest[0];
            len = args.length;
        }
        else {
            args = rest;
        }

        for (let i = 0; i < len; i++) {
            str = str.replace(new RegExp('\\{' + i + '\\}', 'g'), args[i]);
        }

        return str;
    }
}