/*
   Copyright (C) 2001-2006, William Joseph.
   All Rights Reserved.

   This file is part of GtkRadiant.

   GtkRadiant is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.

   GtkRadiant is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GtkRadiant; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */

#include "wal32.h"

#include "ifilesystem.h"

#include "bytestreamutils.h"
#include "imagelib.h"

typedef unsigned char byte;

const int M32_NAME_LENGTH = 128;
const int M32_MIPMAP_COUNT = 16;

typedef struct m32_header_t {
    int version;
    char name[M32_NAME_LENGTH];
    char altname[M32_NAME_LENGTH];                      // texture substitution
    char animname[M32_NAME_LENGTH];                     // next frame in animation chain
    char damagename[M32_NAME_LENGTH];                   // image that should be shown when damaged
    unsigned width[M32_MIPMAP_COUNT], height[M32_MIPMAP_COUNT];
    unsigned offsets[M32_MIPMAP_COUNT];
    int flags;
    int contents;
    int value;
    float scale_x, scale_y;
    int mip_scale;

    // detail texturing info
    char dt_name[M32_NAME_LENGTH];              // detailed texture name
    float dt_scale_x, dt_scale_y;
    float dt_u, dt_v;
    float dt_alpha;
    int dt_src_blend_mode, dt_dst_blend_mode;

    int unused[20];                         // future expansion to maintain compatibility with h2
} m32_header_t;


Image *LoadM32Buff(byte *buffer)
{
    PointerInputStream inputStream(buffer);

    inputStream.seek(4 // version
                     + M32_NAME_LENGTH // name
                     + M32_NAME_LENGTH // altname
                     + M32_NAME_LENGTH // animname
                     + M32_NAME_LENGTH); // damagename
    int w = istream_read_uint32_le(inputStream);
    inputStream.seek(4 * (M32_MIPMAP_COUNT - 1)); // remaining widths
    int h = istream_read_uint32_le(inputStream);
    inputStream.seek(4 * (M32_MIPMAP_COUNT - 1)); // remaining heights
    int offset = istream_read_uint32_le(inputStream);
    inputStream.seek(4 * (M32_MIPMAP_COUNT - 1)); // remaining offsets
    int flags = istream_read_uint32_le(inputStream);
    int contents = istream_read_uint32_le(inputStream);
    int value = istream_read_uint32_le(inputStream);

    RGBAImageFlags *image = new RGBAImageFlags(w, h, flags, contents, value);

    const byte *source = buffer + offset;
    std::copy(source, source + (w * h * 4), image->getRGBAPixels());

    return image;
}

Image *LoadM32(ArchiveFile &file)
{
    ScopedArchiveBuffer buffer(file);
    return LoadM32Buff(buffer.buffer);
}