using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using System.IO;
using System.Text;

using Sog;

namespace bill_statistics
{
    public static class LogFileListSvc
    {
        public static List<string> AllFileName = new List<string>();
        public static string strDir;

        public static void ReadDataFromFile()
        {
            strDir = "../log/bill";
            if (OSUtils.IsWindows() == false)
            {
                strDir = "../../publish/log/bill";
            }

            DirectoryInfo dir = new DirectoryInfo(strDir);


            FileInfo[] allFile = dir.GetFiles();
            foreach (FileInfo fi in allFile)
            {
                int iFileNameLength = fi.Name.Length;

                if (fi.Name.Contains("bill_") && fi.Name.Contains(".log")
                    && fi.Name[iFileNameLength -1] == 'g' && fi.Name[iFileNameLength - 2] == 'o' && fi.Name[iFileNameLength - 3] == 'l')
                {
                    //兼容2种格式 1 "bill_2016_1_1_0.log" 2 bill_2016-11-18_10.log

                    //说明是老格式
                    if (fi.Name[9] == '_')
                    {
                        string[] splits = fi.Name.Split('_');

                        for (int i = 2; i < 5; i++)
                        {
                            // "1" "1.log"
                            if (splits[i].Length == 1 || (i == 4 && splits[i].Length == 5))
                            {
                                splits[i] = "0" + splits[i];
                            }
                        }

                        string newFileName = string.Format("bill_{0}-{1}-{2}_{3}", splits[1], splits[2], splits[3], splits[4]);
                        string newFileFullPathName = strDir + "/" + newFileName;
                        if (File.Exists(newFileFullPathName) == false)
                        {
                            fi.MoveTo(newFileFullPathName);

                            AllFileName.Add(newFileName);
                        }
                        else
                        {
                            File.Delete(fi.FullName);
                        }
                    }
                    else
                    {
                        AllFileName.Add(fi.Name);
                    }
                }
            }

            //排序

            AllFileName.Sort();

            DeleteNoUseFileByMode();
        }

        private static void DeleteNoUseFileByMode()
        {
            //bill_2016-10-20_15.log
            //正常小时数据，导上个小时数据,不计算留存什么的
            if (BillMode.Mode == BillModeType.EXPORT_HOUR_LOG)
            {
                //留最后2个文件
                while (AllFileName.Count > 2)
                {
                    AllFileName.RemoveAt(0);
                }

                //如果有2个，判断最后一个文件是不是这个小时，如果是，删除，保留上个小时
                if (AllFileName.Count == 2)
                {
                    string filename = AllFileName[1];

                    string strhour = filename.Substring(16, 2);
                    int hour = -1;
                    if (int.TryParse(strhour, out hour) && hour == DateTime.Now.Hour)
                    {
                        AllFileName.RemoveAt(1);
                    }
                }
            }
            //保留2个月的数据,必须0点开始，否则计算会出错
            else if (BillMode.Mode == BillModeType.EXPROT_DAY_STAT)
            {
                //计算2个月数据，为什么呢，应为要计算月数据，必须完整,少了就不正确

                DateTime now = DateTime.Now;
                DateTime todayStarTime = now - now.TimeOfDay;

                //得考虑跨月的情况
                DateTime yestodayStarTime = todayStarTime.AddDays(-1);

                DateTime lastMonthTime = yestodayStarTime.AddMonths(-1);
                DateTime lastlastMonthEndDayStartTime = lastMonthTime.AddDays(-(lastMonthTime.Day));

                //去头
                while (AllFileName.Count > 0)
                {
                    string filename = AllFileName[0];

                    string strYear = filename.Substring(5, 4);
                    string strMonth = filename.Substring(10, 2);
                    string strDay = filename.Substring(13,2);

                    int iYear = 0;
                    int iMonth = 0;
                    int iDay = 0;

                    int.TryParse(strYear, out iYear);
                    int.TryParse(strMonth, out iMonth);
                    int.TryParse(strDay,out iDay);

                    DateTime filenameTime = new DateTime(iYear,iMonth, iDay);

                    if (filenameTime < lastlastMonthEndDayStartTime)
                    {
                        AllFileName.RemoveAt(0);
                        continue;
                    }

                    break;
                }

                //去尾巴
                string strToday = todayStarTime.ToString("u");
                strToday = strToday.Substring(0, 10);
                while (AllFileName.Count > 0)
                {
                    string lastfilename = AllFileName.Last();
                    string lastDay = lastfilename.Substring(5, 10);
                    if (lastDay == strToday)
                    {
                        AllFileName.RemoveAt(AllFileName.Count - 1);
                    }
                    else
                    {
                        break;
                    }
                }
            }
            else if (BillMode.Mode == BillModeType.EXPROT_TODAY_STAT)
            {
                //计算2天的数据,昨天和今天

                DateTime now = DateTime.Now;
                DateTime todayStarTime = now - now.TimeOfDay;

                DateTime yestodayStarTime = todayStarTime.AddDays(-1);

                //去头
                while (AllFileName.Count > 0)
                {
                    string filename = AllFileName[0];

                    string strYear = filename.Substring(5, 4);
                    string strMonth = filename.Substring(10, 2);
                    string strDay = filename.Substring(13, 2);

                    int iYear = 0;
                    int iMonth = 0;
                    int iDay = 0;

                    int.TryParse(strYear, out iYear);
                    int.TryParse(strMonth, out iMonth);
                    int.TryParse(strDay, out iDay);

                    DateTime filenameTime = new DateTime(iYear, iMonth, iDay);

                    if (filenameTime < yestodayStarTime)
                    {
                        AllFileName.RemoveAt(0);
                        continue;
                    }

                    break;
                }

                //这个小时理论上才开始几秒到1分钟，所以需要删除
                if (AllFileName.Count > 0)
                {
                    string filename = AllFileName[AllFileName.Count - 1];

                    string strhour = filename.Substring(16, 2);
                    int hour = -1;
                    if (int.TryParse(strhour, out hour) && hour == DateTime.Now.Hour)
                    {
                        AllFileName.RemoveAt(AllFileName.Count - 1);
                    }
                }
            }
            else if(BillMode.Mode == BillModeType.LONG_KEEP)
            {
                //最多200天数据
                while (AllFileName.Count > 24*182)
                {
                    AllFileName.RemoveAt(0);
                }
            }
            else
            {
                //判断最后一个文件是不是这个小时，如果是，删除
                if (AllFileName.Count > 0)
                {
                    string filename = AllFileName[AllFileName.Count - 1];

                    string strhour = filename.Substring(16, 2);
                    int hour = -1;
                    if (int.TryParse(strhour, out hour) && hour == DateTime.Now.Hour)
                    {
                        AllFileName.RemoveAt(AllFileName.Count - 1);
                    }
                }
            }

        }

        public static void DeleteNoUseFileByOnlyDayNumber(int onlyDayNumber)
        {
            int hourCount = 24 * onlyDayNumber;

            //最多n天
            while(AllFileName.Count > hourCount)
            {
                AllFileName.RemoveAt(0);
            }
        }
    }
}