// 统一暴露工具，供其他地方调用

// 数组转对象
export function arrToObj(arr) {
  // 参数必须是一个数组
  if (!Array.isArray(arr)) {
    throw new Error("type err: arr 必须是一个数组");
  }
  // 存放返回结果
  const obj = {};
  arr.map((item) => {
    obj[Object.keys(item)[0]] = item[Object.keys(item)[0]];
  });
  return obj;
}

/*
*  文件流转换为url
*  @params file 文件流
*  @return url
*/
export function getObjectURL(file) {
  console.log(file)
  let url = null;
  if (window.createObjectURL != undefined) { // basic
    url = window.createObjectURL(file);
  } else if (window.webkitURL != undefined) { // webkit or chrome
    url = window.webkitURL.createObjectURL(file);
  } else if (window.URL != undefined) { // mozilla(firefox)
    url = window.URL.createObjectURL(file);
  }
  return url;
}

/**
* @description 文件下载（兼容IE）
* @param {Object} response options 接口响应的数据 包括文件流及保文信息
* @param {String} file_name 文件名称
* @returns {undefined} undefined
*/
export function downloadFile(response, file_name = "ExportFile") {
  const fileType = response.headers["content-type"] || "application/pdf";
  const disposition = response.headers["content-disposition"]
  if (disposition) {
    file_name = disposition.split("filename=")[1]
  }
  const blob = new Blob([response.data], { type: `${fileType};charset=utf-8` });

  const ie = navigator.userAgent.match(/MSIE\s([\d.]+)/),
    ie11 = navigator.userAgent.match(/Trident\/7.0/) && navigator.userAgent.match(/rv:11/),
    ieEDGE = navigator.userAgent.match(/Edge/g),
    ieVer = ie ? ie[1] : ie11 ? 11 : ieEDGE ? 12 : -1;

  if (ie && ieVer < 10) {
    this.message.error('No blobs on IE<10');
    return;
  }
  if (ieVer > -1) {
    window.navigator.msSaveBlob(blob, file_name);
    return {}
  } else {
    const url = window.URL.createObjectURL(blob);
    return {
      url,
      file_name
    }
  }
}

//导出excel
export function exportFile(res, file_name) {
  let blob = new Blob([res.data], {
    type:"application/vnd.ms-excel;charset=utf-8"
  });
  let url=window.URL.createObjectURL(blob);
  let aLink=document.createElement("a");
  aLink.style.display="none";
  aLink.href=url;
  aLink.setAttribute("download", file_name);
  document.body.appendChild(aLink);
  aLink.click();
  document.body.removeChild(aLink);
  window.URL.revokeObjectURL(url);
}

export const numValid = /^([1-9][0-9]*|0)([.][0-9]+)?$/

// 对象转换成query字符串
export const toQuery = (params) => {
  if (!params) {
    return "";
  }
  let query = [];
  for (let i in params) {
    query.push(`${i}=${params[i]}`);
  }
  return query.join("&");
}
// 数值计算
export const accuracy = {
  division(arg1, arg2) {
      //除法
      var t1 = 0,
          t2 = 0,
          r1,
          r2;
      try {
          t1 = arg1.toString().split('.')[1].length;
      } catch(e) {
          console.log(e);
      }
      try {
          t2 = arg2.toString().split('.')[1].length;
      } catch(e) {
          console.log(e);
      }
      if(Math) {
          r1 = Number(arg1.toString().replace('.', ''));
          r2 = Number(arg2.toString().replace('.', ''));
          return this.multiply(r1 / r2, Math.pow(10, t2 - t1));
      }
  },
  multiply(arg1, arg2) {
      //乘法
      var m = 0,
          s1 = arg1.toString(),
          s2 = arg2.toString();
      try {
          m += s1.split('.')[1].length;
      } catch(e) {
          console.log(e)
      }
      try {
          m += s2.split('.')[1].length;
      } catch(e) {
          console.log(e)
      }
      return Number(s1.replace('.', '')) * Number(s2.replace('.', '')) / Math.pow(10, m);
  },
  add(arg1, arg2) {
      //加法
      var r1, r2, m;
      try {
          r1 = arg1.toString().split('.')[1].length;
      } catch(e) {
          r1 = 0;
      }
      try {
          r2 = arg2.toString().split('.')[1].length;
      } catch(e) {
          r2 = 0;
      }
      m = Math.pow(10, Math.max(r1, r2));
      console.log(this.multiply(arg1, m), this.multiply(arg2, m))
      return(this.multiply(arg1, m) + this.multiply(arg2, m)) / m;
  },
  subtract(arg1, arg2) {
      //减法
      var r1, r2, m, n;
      try {
          r1 = arg1.toString().split('.')[1].length;
      } catch(e) {
          r1 = 0;
      }
      try {
          r2 = arg2.toString().split('.')[1].length;
      } catch(e) {
          r2 = 0;
      }
      m = Math.pow(10, Math.max(r1, r2));
      n = r1 >= r2 ? r1 : r2;
      return((arg1 * m - arg2 * m) / m).toFixed(n);
  },
  // 计算一个数组的总和
  sum(arr) {
      let result = 0;
      arr.forEach(item => {
          result = this.add(result, item);
      })
      return result;
  },
  // 计算一个数组的总和 fn是对每项数据的处理方式
  sumBy(arr, fn) {
      let result = 0;
      arr.forEach(item => {
          let val = item;
          if(fn) {
              val = fn(item)
          }
          result = this.add(result, val);
      })
      return result;
  },
  toCeil(num, p = 4) {
      num = isNaN(num) ? 0 : num;
      p = isNaN(p) ? 0 : p;
      let precision = Math.pow(10, p);
      return Math.ceil((num * precision).toFixed(1)) / precision;
  },
  toFloor(num, p = 4) {
      num = isNaN(num) ? 0 : num;
      p = isNaN(p) ? 0 : p;
      let precision = Math.pow(10, p);
      return Math.floor((num * precision).toFixed(1)) / precision;
  }
};