//! \file       ImageNGP.cs
//! \date       Sun Nov 08 16:11:56 2015
//! \brief      NA Game System image format.
//
// Copyright (C) 2015 by morkt
//
// 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 GameRes.Compression;
using System.ComponentModel.Composition;
using System.IO;
using System.Windows.Media;

namespace GameRes.Formats.Nags
{
    internal class NgpMetaData : ImageMetaData
    {
        public int  PackedSize;
        public int  UnpackedSize;
    }

    [Export(typeof(ImageFormat))]
    public class NgpFormat : ImageFormat
    {
        public override string         Tag { get { return "NGP"; } }
        public override string Description { get { return "NAGS engine image format"; } }
        public override uint     Signature { get { return 0x2050474E; } } // 'NGP '

        public override ImageMetaData ReadMetaData (Stream stream)
        {
            stream.Position = 0x12;
            using (var reader = new ArcView.Reader (stream))
            {
                int packed_size = reader.ReadInt32();
                uint width      = reader.ReadUInt32();
                uint height     = reader.ReadUInt32();
                int bpp         = reader.ReadUInt16() * 8;
                reader.BaseStream.Position = 0x100;
                int unpacked_size = reader.ReadInt32();
                if (packed_size <= 0 || unpacked_size <= 0)
                    return null;
                return new NgpMetaData
                {
                    Width = width,
                    Height = height,
                    BPP = bpp,
                    PackedSize = packed_size,
                    UnpackedSize = unpacked_size,
                };
            }
        }

        public override ImageData Read (Stream stream, ImageMetaData info)
        {
            var meta = (NgpMetaData)info;
            using (var input = new StreamRegion (stream, 0x104, meta.PackedSize, true))
            using (var z = new ZLibStream (input, CompressionMode.Decompress))
            {
                var pixels = new byte[meta.UnpackedSize];
                if (pixels.Length != z.Read (pixels, 0, pixels.Length))
                    throw new EndOfStreamException();
                PixelFormat format;
                if (32 == meta.BPP)
                    format = PixelFormats.Bgra32;
                else if (24 == meta.BPP)
                    format = PixelFormats.Bgr24;
                else if (8 == meta.BPP)
                    format = PixelFormats.Gray8;
                else
                    throw new System.NotSupportedException ("Not supported NGP image color depth");

                return ImageData.Create (info, format, null, pixels);
            }
        }

        public override void Write (Stream file, ImageData image)
        {
            throw new System.NotImplementedException ("NgpFormat.Write not implemented");
        }
    }
}
