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

namespace MECF.Framework.Common.Utilities
{
     public class FileHelper
    {
        //定义一个用于保存静态变量的实例
        private static FileHelper instance = null;
        //定义一个保证线程同步的标识
        private static readonly object locker = new object();
        //构造函数为私有，使外界不能创建该类的实例
        private FileHelper() { }
        public static FileHelper Instance
        {
            get
            {
                if (instance == null)
                {
                    lock (locker)
                    {
                        if (instance == null) instance = new FileHelper();
                    }
                }
                return instance;
            }
        }

        public void SaveNewLineDataToTxt(string dir, string filePath, string text, bool isAppend = false)
        {
            if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
            filePath = filePath + ".txt";
            using (StreamWriter sw = new StreamWriter(filePath, isAppend, Encoding.UTF8))
            {
                sw.WriteLine(text);
                sw.Flush();
                sw.Close();
            }
        }

        public void SaveNewLineDataToTxt(string fullFilePath, string text, bool isAppend = false)
        {
            string dir = fullFilePath.Substring(0, fullFilePath.LastIndexOf('\\'));
            if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
            using (StreamWriter sw = new StreamWriter(fullFilePath, isAppend, Encoding.UTF8))
            {
                sw.WriteLine(text);
                sw.Flush();
                sw.Close();
            }
        }

        public void SaveText(string fullFileName, string WriteTxt)
        {
            try
            {
                string dir= fullFileName.Substring(0, fullFileName.LastIndexOf('\\'));
                if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
                FileStream fs = new FileStream(fullFileName,
                    FileMode.OpenOrCreate, FileAccess.Write);
                StreamWriter streamWriter = new StreamWriter(fs, Encoding.UTF8);
                streamWriter.Flush();
                streamWriter.BaseStream.Seek(0, SeekOrigin.End);
                streamWriter.WriteLine(WriteTxt);
                streamWriter.Flush();
                streamWriter.Close();
            }
            catch { }
        }

        public void SaveText(string dir, string fileName, string WriteTxt)
        {
            try
            {
                if (!Directory.Exists(dir)) Directory.CreateDirectory(dir);
                FileStream fs = new FileStream(dir + "\\" + fileName + ".txt",
                    FileMode.OpenOrCreate, FileAccess.Write);
                StreamWriter streamWriter = new StreamWriter(fs, Encoding.UTF8);
                streamWriter.Flush();
                streamWriter.BaseStream.Seek(0, SeekOrigin.End);
                streamWriter.WriteLine(WriteTxt);
                streamWriter.Flush();
                streamWriter.Close();
            }
            catch { }
        }

        public string ReadAllText(string filePath)
        {
            if (!File.Exists(filePath)) return filePath + "，文件不存在";
            return File.ReadAllText(filePath);
        }

        public string ReadFileStream(string filePath)
        {
            string result = string.Empty;
            try
            {
                if (!File.Exists(filePath)) return filePath + "，文件不存在";
                FileStream fileStream = new FileStream(filePath, FileMode.Open,
                    FileAccess.ReadWrite, FileShare.ReadWrite);
                StreamReader sr = new StreamReader(fileStream, Encoding.Default);
                result = sr.ReadToEnd();
                sr.Close(); 
                fileStream.Close();
            }
            catch { return result; }
            return result;
        }
    }
}