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

namespace ArchiveUnpack
{
    public class FileUnpack
    {
        protected FileInfo _File;
        protected FileStream _File_FS;
        protected int _Index;

        public FileUnpack()
        {
        }

        public FileUnpack(string FilePath)
        {
            if (File.Exists(FilePath))
            {
                _File = new FileInfo(FilePath);

                _File_FS = File.Open(_File.FullName, FileMode.Open);
            }

        }

        ~FileUnpack()
        {
            if(_File_FS!=null)
            {
                _File_FS.Dispose();
                _File_FS.Close();
            }
        }

        public static void Log(string format,params object[] objs)
        {
            Console.WriteLine(string.Format(format,objs));
        }

        public virtual void ReadHeader()
        {

        }

        public virtual void Unpack()
        {
            
        }

        public virtual int ReadInt32()
        {
            byte[] bsInt32 = new byte[4];
            _File_FS.Read(bsInt32, 0, 4);
            _Index += 4;
            return BitConverter.ToInt32(bsInt32,0);
        }

        public virtual string ReadString(int len)
        {
            byte[] bNewString = new byte[len];
            _File_FS.Read(bNewString, 0, len);
            _Index += len;
            return Encoding.UTF8.GetString(bNewString);
        }

        public virtual int ReadByte()
        {
            int b = _File_FS.ReadByte();
            _Index += 1;
            return b;
        }
    }
}