import MD5 from 'md5'
import Axios from 'axios'

let pendingRequest:any = new Map()
let delArr = ['user_req_id']

// 解析
const queryParse = query => {
    query = query.substring(query.indexOf('?') + 1)
    let arr = query.split('&')
    let params = {}
    arr.forEach(item => {
      let key = item.substring(0, item.indexOf('='))
      let val = item.substring(item.indexOf('=') + 1)
      params[key] = val
    })
    return params
}

const isJsonFn = (str) => {
    if (isNaN(Number(str))) {
      try {
        JSON.parse(str);
        return true;
      } catch (e) {
        return false;
      }
    } 
    return false;
}

const generateReqKey = (apiMiddlewareContext:any , cacheJson:any, delList?: string[]) => {
    try {
        if(delList?.length){
            delArr = delList
        }
        const url = apiMiddlewareContext.url  || apiMiddlewareContext?.config?.url
        const cacheList = cacheJson.cacheList.filter(ele=> url.indexOf(ele.cacheUrl) > 0)
        const config = apiMiddlewareContext || apiMiddlewareContext.config || {}
        if(cacheList?.length){
            const cacheItem = cacheList[0]
            // 参数Data
            let paramItem
            if(config.method=='get'){
                if(config.params){
                    paramItem = config.params  || {}
                    const isJson = isJsonFn(paramItem)
                    if(isJson){
                        paramItem = JSON.parse(paramItem)
                    }
                    delArr.forEach(ele=>{
                        if(paramItem && Object.keys(paramItem).length){
                            if(paramItem[ele]){
                                delete paramItem[ele]
                            }
                        }
                    })
                }else{
                    if(url.indexOf('?')>0){
                        let paramUrlObj:any = queryParse(url) || {}
                        delArr.forEach(ele=>{
                        if(paramUrlObj && Object.keys(paramUrlObj).length){
                            if(paramUrlObj[ele]){
                                delete paramUrlObj[ele]
                            }
                        }
                        })
                        paramItem = paramUrlObj
                    }
                }
            }else{
                paramItem = config.data || {}
                const isJson = isJsonFn(paramItem)
                if(isJson){
                    paramItem = JSON.parse(paramItem)
                }
                if(Array.isArray(paramItem)){
                    paramItem.forEach(ele=>{
                        Object.keys(ele).forEach(key=>{
                            if(delArr.includes(key)){
                                delete ele[key]
                            }
                        })
                    })
                }else{
                    delArr.forEach(ele=>{
                        if(Object.keys(paramItem).length){
                            if(paramItem[ele]){
                                delete paramItem[ele]
                            }
                        }
                    })
                }
            }
            paramItem = JSON.stringify(paramItem)
            const urlHref = window.location.href?.split('?')[0] || ''
            // 路由 地址 方法 参数
            const requestKey = `${urlHref}_${config.method}_${cacheItem.cacheUrl}_${paramItem}`
            const abstract = MD5(requestKey)
            return abstract
        }
    } catch (error) {
        return null
    }
}

export const addPendingRequest = (apiMiddlewareContext:any , cacheJson:any, delList?: string[]) => {
    const requestKey = generateReqKey(apiMiddlewareContext, cacheJson, delList)
    if (requestKey && !pendingRequest.has(requestKey)) { //判断pendingRequest中是否存在key
        apiMiddlewareContext.cancelToken = new Axios.CancelToken(cancel => {
          pendingRequest.set(requestKey, cancel) 
        })
    }
}

export const removePendingRequest = (apiMiddlewareContext:any , cacheJson:any, delList?: string[]) => {
    const requestKey = generateReqKey(apiMiddlewareContext, cacheJson, delList)
    if (requestKey && pendingRequest.has(requestKey)) {
        const cancel = pendingRequest.get(requestKey);
        cancel(requestKey);
        pendingRequest.delete(requestKey);
    }
}