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

namespace Common
{
    public class LogHelper
    {
        public static string LogInfo = AppDomain.CurrentDomain.BaseDirectory + "Logs\\";

        /// <summary>
        /// 获取日志存储路径
        /// </summary>
        /// <param name="logfilename"></param>
        /// <param name="type">0正常信息，1错误信息</param>
        /// <returns></returns>
        private static string GetLogFilePath(string logfilename, int type = 0)
        {

            if (!System.IO.Directory.Exists(LogInfo))
            {
                System.IO.Directory.CreateDirectory(LogInfo);
            }
            string log = LogInfo + DateTime.Now.ToString("yyyy-MM-dd") + logfilename + ".txt";
            if (type != 0)
            {
                log = LogInfo +  logfilename + ".txt";
            }
            return log;
        }
        /// <summary>
        /// 保存的最多日志数量
        /// </summary>
      //  private static int MaxLogCount = 30;

        /// <summary>
        /// 日志信息
        /// </summary>
        /// <param name="msg"></param>
        /// <param name="logfilename"></param>
        public static void Info(string msg, string logfilename = "",int type = 0)
        {
            try
            {
                DeleteLog();

                string datapath = GetLogFilePath(logfilename, type);
                if (type != 0)
                {
                    using (FileStream fs = new FileStream(datapath, FileMode.Create))
                    {
                        using (StreamWriter sw = new StreamWriter(fs))
                        {
                            //开始写入
                            sw.WriteLine("当前时间：" + DateTime.Now.ToString());
                            sw.WriteLine("日志级别：Error");
                            sw.WriteLine("偏移量："+ logfilename);
                            sw.WriteLine("日志信息：" + msg);
                            //清空缓冲区
                            sw.Flush();
                            //关闭流
                            sw.Close();
                            fs.Close();
                        }
                    }
                    return;
                }
                if (System.IO.File.Exists(datapath))//追加
                {
                    using (FileStream fs = new FileStream(datapath, FileMode.Append))
                    {
                        using (StreamWriter sw = new StreamWriter(fs))
                        {
                            //开始写入
                            sw.WriteLine("\n");
                            sw.WriteLine("当前时间：" + DateTime.Now.ToString());
                            sw.WriteLine("日志级别：Info");
                            sw.WriteLine("日志信息：" + msg);
                            //清空缓冲区
                            sw.Flush();
                            //关闭流
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
                else//创建
                {
                    using (FileStream fs = new FileStream(datapath, FileMode.Create))
                    {
                        using (StreamWriter sw = new StreamWriter(fs))
                        {
                            //开始写入
                            sw.WriteLine("当前时间：" + DateTime.Now.ToString());
                            sw.WriteLine("日志级别：Info");
                            sw.WriteLine("日志信息：" + msg);
                            //清空缓冲区
                            sw.Flush();
                            //关闭流
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
            }
            catch
            {

            }
        }

        /// <summary>
        /// 错误日志
        /// </summary>
        /// <param name="ex"></param>
        /// <param name="logfilename"></param>
        public static void Error(Exception ex, string logfilename = "", int type = 0)
        {
            try
            {
                DeleteLog();

                string datapath = GetLogFilePath(logfilename, type);

                if (System.IO.File.Exists(datapath))//追加
                {
                    using (FileStream fs = new FileStream(datapath, FileMode.Append))
                    {
                        using (StreamWriter sw = new StreamWriter(fs))
                        { //开始写入
                            sw.WriteLine("\n");
                            sw.WriteLine("当前时间：" + DateTime.Now.ToString());
                            sw.WriteLine("异常级别：Error");
                            sw.WriteLine("异常信息：" + ex.Message);
                            sw.WriteLine("异常对象：" + ex.Source);
                            sw.WriteLine("异常位置：" + ex.StackTrace);
                            //清空缓冲区
                            sw.Flush();
                            //关闭流
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
                else//创建
                {
                    using (FileStream fs = new FileStream(datapath, FileMode.Create))
                    {
                        using (StreamWriter sw = new StreamWriter(fs))
                        {
                            //开始写入
                            sw.WriteLine("当前时间：" + DateTime.Now.ToString());
                            sw.WriteLine("异常级别：Error");
                            sw.WriteLine("异常信息：" + ex.Message);
                            sw.WriteLine("异常对象：" + ex.Source);
                            sw.WriteLine("异常位置：" + ex.StackTrace);
                            //清空缓冲区
                            sw.Flush();
                            //关闭流
                            sw.Close();
                            fs.Close();
                        }
                    }
                }
            }
            catch
            {

            }
        }



        /// <summary>
        /// 删除多余日志
        /// </summary>
        private static void DeleteLog()
        {
            //不必每天都删除日志，整10天删除
            if (!(DateTime.Now.Day % 10 == 0))
            {
                return;
            }
            DirectoryInfo dic = new DirectoryInfo(LogInfo);
            if (dic.Exists)
            {
                try
                {
                    //清理10天前的日志文件
                    dic.GetFiles("*.txt", SearchOption.AllDirectories).Where(n => (DateTime.Now - n.LastWriteTime).TotalDays > 10).ToList().TrueForAll(n => { n.Delete(); return true; });
                }
                catch (Exception ex)
                {
                    Error(ex);
                }
            }
        }
    }
}