var http = require('http')
var fs = require('fs')
const router = require('./router')
const imgscan = require('./utils/scanImgFile')
const generateCode = require('./utils/generateCode')
const struils = require('./utils/stringUtil')

// 默认显示当天的图片
var showSetting = 'day'

function minusDays(DateA, DateB) {
  var time1 = Date.parse(DateA)
  var time2 = Date.parse(DateB)
  var nDays = Math.abs(parseInt((time2 - time1) / 1000 / 3600 / 24))
  return nDays
}

/**
 * 根据日期判断哪些文件当前需要加载
 * keys 传入扫描过的文件路径
 */
function getFileByDate(keys) {
  var daylist = []
  var weeklist = []
  var monthlist = []
  var yearlist = []
  for (var i = 0; keys != undefined && keys != null && i < keys.length; i++) {
    var key = keys[i]
    stats = fs.statSync(__dirname + '/images/' + key)
    if (stats) {
      var fileDate = new Date(stats['birthtime'])
      var currentDate = new Date()
      var days = minusDays(currentDate, fileDate)
      if (days < 1) {
        daylist.push(key)
      } else if (days < 7) {
        weeklist.push(key)
      }
      if (days < 30) {
        monthlist.push(key)
      }
      if (days < 365) {
        yearlist.push(key)
      }
    }
  }

  return {
    day: daylist,
    week: weeklist,
    month: monthlist,
    year: yearlist,
  }
}

function start() {
  const server = http.createServer(function (req, res) {
    var url = ''
    if (struils.trim(req.url) == '/') url = ''
    else url = struils.trim(req.url.substring(1))
    var links = url.split('?')
    if (links.length != 1) {
      showSetting = links[1].split('=')[1]
    }
    console.log(url)

    // 显示内容
    router.processRoute(req, res)

    // 扫描文件
    var keys = imgscan.scan(req, res)
    // 根据文件日期丢弃部分数据
    var datas = getFileByDate(keys)
    if (keys.length != 0) {
      generateCode.process(datas, req.url)
    }
  })

  server.listen(3001, 'localhost', () => {
    console.log(`Server running at http://localhost:3001/`)
  })
}

exports.start = start