module.exports = {
writeExcel : function (headers,data,file,callback) {
if(data.length ==0){
var obj = {}
for(var v of headers){
obj[v] = ''
}
data.push(obj)
}
_writeExcel(headers,callback)
},/**

• 获取excel原始信息
• @param path 文件路径
  */
  info : function(path){
  return _info(path)
  },/**
• 格式化excel原始信息
• @param path 文件路径
  */
  formate_info : function (path) {
  return info_formate_info(path).formate
  },info_formate_info : function (path) {
  return info_formate_info(path)
  }

}

var _info = function(path) {
var k = XLSX.readFile(path,{type: 'base64'});
var result = {}
k.SheetNames.forEach(function(sheetName) {
var worksheet = k.Sheets[sheetName];
result[sheetName] = XLSX.utils.sheet_to_json(worksheet);
});
return result
}

var info_formate_info = function(path){
var info = _info(path)
var result = {}
for(var value in info){
result[value] = {}
}
for(var key_info in info ){
var array = info[key_info]
if(array_utils.isArray(array) || array.length>0){
var keys_array = Object.keys(array[0])
var obj = {}
for(var value of keys_array){
obj[value] = []
}
for( var key in obj ){
var subject_clone = JSON.parse(JSON.stringify(array))
subject_clone.filter( (v)=>{
for(var k in v){
if(k!=key){
delete v[k]
}
}
return v;
})
var subject_key_value = Array.from(array_utils.arrayQC(subject_clone),v => v[key] )
var obA = []
for(var v of subject_key_value){
var obk = {
id : null,v : v
}
for(var ke in keys_array){
var thisIndex = keys_array.findIndex(x=>x==keys_array[ke])
var currentIndex = keys_array.findIndex(x=>x==key)
if( thisIndex < currentIndex){
try {
var thisObj = array.find(x=>x[ key ] == v )
obk[keys_array[ke]] = thisObj[ keys_array[ke] ]
}catch (e){
console.error(e)
}
}
}

 obA.push(obk)
}
obj[key] = obA

}
result[key_info]= obj
}
}
return {
info : info,formate : result
}
}

var _writeExcel = function (headers,callback) {
var _headers = headers
var _data = data;
var headers = _headers
// 为 _headers 添加对应的单元格位置
.map((v,i) => Object.assign({},{
v: v,position:num(i)+1
}))
// 转换成 worksheet 需要的结构
.reduce((prev,next) => Object.assign({},prev,{[next.position]: {v: next.v}}),{});
var data = _data
.map((v,i) => _headers.map((k,j) => Object.assign({},{
v: v[k],position:num(j) + (i+2)
})))
// 对刚才的结果进行降维处理（二维数组变成一维数组）
.reduce((prev,next) => prev.concat(next))
// 转换成 worksheet 需要的结构
.reduce((prev,{});
// 合并 headers 和 data
// console.log("测试data",data)
var output = Object.assign({},headers,data);
// 获取所有单元格的位置
var outputPos = Object.keys(output);
// 计算出范围
var ref = outputPos[0] + ':' + outputPos[outputPos.length - 1];
// 构建 workbook 对象
var wb = {
SheetNames: ['Sheet1'],Sheets: {
'Sheet1': Object.assign({},output,{ '!ref': ref })
}
};

// 导出 Excel
XLSX.writeFileAsync( file,wb,function (err) {
callback(err)
});
}
//定位Excel位置
var num=function(i){
var n=parseInt(i+65)
if(n>90){
n=String.fromCharCode(65)+String.fromCharCode(i+39)
return n
}else {
n=String.fromCharCode(n)
return n
}

}