//
// Copyright (c) 2008-2011, Kenneth Bell
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the "Software"),
// to deal in the Software without restriction, including without limitation
// the rights to use, copy, modify, merge, publish, distribute, sublicense,
// and/or sell copies of the Software, and to permit persons to whom the
// Software is furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
// DEALINGS IN THE SOFTWARE.
//

using System;
using System.IO;

namespace DiscUtils.Streams
{
    /// <summary>
    /// Base class for reading binary data from a stream.
    /// </summary>
    public abstract class DataReader
    {
        private const int _bufferSize = sizeof(UInt64);

        protected readonly Stream _stream;

        protected byte[] _buffer;

        public DataReader(Stream stream)
        {
            _stream = stream;
        }

        public long Length
        {
            get { return _stream.Length; }
        }

        public long Position
        {
            get { return _stream.Position; }
        }

        public void Skip(int bytes)
        {
            ReadBytes(bytes);
        }

        public abstract ushort ReadUInt16();

        public abstract int ReadInt32();

        public abstract uint ReadUInt32();

        public abstract long ReadInt64();

        public abstract ulong ReadUInt64();

        public virtual byte[] ReadBytes(int count)
        {
            return StreamUtilities.ReadExact(_stream, count);
        }

        protected void ReadToBuffer(int count)
        {
            if (_buffer == null)
            {
                _buffer = new byte[_bufferSize];
            }

            StreamUtilities.ReadExact(_stream, _buffer, 0, count);
        }
    }
}