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

namespace SimpleServer
{
    public class LogHelper : IDisposable
    {
        private static LogHelper logHelper;
        private static object singleLock = new object();
        private string logPath = Path.Combine(System.Environment.CurrentDirectory, "Log.txt");
        private string spaceSymbols = "\r\n\r\n--------------------------------------------\r\n\r\n";
        private byte[] spaceSymbolsBytes;
        private FileStream fileStream;

        private LogHelper()
        {
        }

        public static LogHelper GetInstance()
        {
            if (logHelper == null)
            {
                lock (singleLock)
                {
                    if (logHelper == null)
                    {
                        logHelper = new LogHelper();
                    }
                }
            }
            return logHelper;
        }
        
        public void SetLogPath(string logPath)
        {
            this.logPath = Path.Combine(logPath, "Log.txt");
        }

        public void Init()
        {
            fileStream = new FileStream(logPath, FileMode.OpenOrCreate, FileAccess.ReadWrite);
            spaceSymbolsBytes = Encoding.Default.GetBytes(spaceSymbols);
        }

        public void SetSpaceSymbols(string spaceSymbols)
        {
            this.spaceSymbols = spaceSymbols;
            this.spaceSymbolsBytes = Encoding.Default.GetBytes(spaceSymbols);
        }

        public void Log(string content)
        {
            if (!string.IsNullOrEmpty(content))
            {
                fileStream.Seek(0, SeekOrigin.End);
                byte[] bytes = Encoding.Default.GetBytes(content);
                fileStream.Write(bytes, 0, bytes.Length);
                fileStream.Write(spaceSymbolsBytes, 0, spaceSymbolsBytes.Length);
                fileStream.Flush();
            }
        }

        public void Dispose()
        {
            if (fileStream != null)
            {
                fileStream.Dispose();
            }
        }
    }
}