/*
SW_TEXTURE_EXTRAS.CPP

	Copyright (C) 2007 Gregory Smith
 
	This program 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.

	This program 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.

	This license is contained in the file "COPYING",
	which is included with this source code; it is available online at
	http://www.gnu.org/licenses/gpl.html

*/

#include "SW_Texture_Extras.h"
#include "collection_definition.h"
#include "interface.h"
#include "render.h"
#include "scottish_textures.h"

SW_Texture_Extras *SW_Texture_Extras::m_instance;

extern short bit_depth;
void SW_Texture::build_opac_table()
{
	int num_colors;

	bitmap_definition *bitmap;
	void *shading_tables;
	get_shape_bitmap_and_shading_table(m_shape_descriptor, &bitmap, &shading_tables, 0);

	m_opac_table.resize(MAXIMUM_SHADING_TABLE_INDEXES);

	SDL_PixelFormat *fmt = SDL_GetVideoSurface()->format;
	if (bit_depth == 32)
	{
		for (int i = 0; i < MAXIMUM_SHADING_TABLE_INDEXES; i++)
		{
			float Opacity;
			if (m_opac_type == 1)
			{
				Opacity = 255.0;
			}
			else
			{
				uint32 color = ((uint32 *) shading_tables)[i + MAXIMUM_SHADING_TABLE_INDEXES * (number_of_shading_tables - 1)];
				uint32 r = (((color&fmt->Rmask)>>fmt->Rshift)<<fmt->Rloss);
				uint32 g = (((color&fmt->Gmask)>>fmt->Gshift)<<fmt->Gloss);
				uint32 b = (((color&fmt->Bmask)>>fmt->Bshift)<<fmt->Bloss);
				if (m_opac_type == 2)
				{
					Opacity = (float) (r + g + b) / 3.0F;
					
				}
				else 
				{
					Opacity = (float)std::max(r, std::max(g, b));
				}
			}

			m_opac_table[i] = PIN(int32(m_opac_scale * Opacity + 255 * m_opac_shift + 0.5), 0, 255);
		}
	} 
	else if (bit_depth == 16)
	{
		for (int i = 0; i < MAXIMUM_SHADING_TABLE_INDEXES; i++)
		{
			float Opacity;
			if (m_opac_type == 1)
			{
				Opacity = 255.0;
			}
			else 
			{
				uint16 color = ((uint16 *) shading_tables)[i + MAXIMUM_SHADING_TABLE_INDEXES * (number_of_shading_tables - 1)];
				uint32 r = (((color&fmt->Rmask)>>fmt->Rshift)<<fmt->Rloss);
				uint32 g = (((color&fmt->Gmask)>>fmt->Gshift)<<fmt->Gloss);
				uint32 b = (((color&fmt->Bmask)>>fmt->Bshift)<<fmt->Bloss);		
				if (m_opac_type == 2)
				{
					Opacity = (float) (r + g + b) / 3.0F;
				}
				else
				{
					Opacity = (float)std::max(r, std::max(g, b));
				}
			}
			m_opac_table[i] = PIN(int32(m_opac_scale * Opacity + 255 * m_opac_shift + 0.5), 0, 255);
		}	
	}
}

SW_Texture *SW_Texture_Extras::AddTexture(shape_descriptor ShapeDesc)
{
	short Collection = GET_COLLECTION(GET_DESCRIPTOR_COLLECTION(ShapeDesc));
	short Bitmap = GET_DESCRIPTOR_SHAPE(ShapeDesc);

	if (Bitmap >= texture_list[Collection].size())
	{
		texture_list[Collection].resize(Bitmap + 1);
	}
	return &texture_list[Collection][Bitmap];
}

SW_Texture *SW_Texture_Extras::GetTexture(shape_descriptor ShapeDesc)
{
	short Collection = GET_COLLECTION(GET_DESCRIPTOR_COLLECTION(ShapeDesc));
	short Bitmap = GET_DESCRIPTOR_SHAPE(ShapeDesc);

	if (Bitmap >= texture_list[Collection].size())
		return 0;
	return &texture_list[Collection][Bitmap];
}

void SW_Texture_Extras::Load(short collection_index)
{
	for (std::vector<SW_Texture>::iterator i = texture_list[collection_index].begin(); i != texture_list[collection_index].end(); i++)
	{
		i->build_opac_table();
	}
}

void SW_Texture_Extras::Unload(short collection_index)
{
	// unload all opacity tables
	for (std::vector<SW_Texture>::iterator i = texture_list[collection_index].begin(); i != texture_list[collection_index].end(); i++)
	{
		i->clear_opac_table();
	}
}

class XML_SW_Texture_Parser : public XML_ElementParser
{

	short Collection;
	short Bitmap;
	short OpacityType;
	float OpacityScale;
	float OpacityShift;
	
public:
	bool Start();
	bool HandleAttribute(const char *Tag, const char *Value);
	bool AttributesDone();
	XML_SW_Texture_Parser() : XML_ElementParser("texture") { };
};

bool XML_SW_Texture_Parser::Start()
{
	OpacityType = 0;
	OpacityScale = 1.0;
	OpacityShift = 0.0;

	return true;
}

bool XML_SW_Texture_Parser::HandleAttribute(const char *Tag, const char *Value)
{
	if (StringsEqual(Tag, "coll"))
	{
		return ReadBoundedInt16Value(Value, Collection, 0, NUMBER_OF_COLLECTIONS-1);
	}
	else if (StringsEqual(Tag, "bitmap"))
	{
		return ReadBoundedInt16Value(Value, Bitmap, 0, MAXIMUM_SHAPES_PER_COLLECTION-1);
	}
	else if (StringsEqual(Tag, "opac_type"))
	{
		return ReadBoundedInt16Value(Value, OpacityType, 0, 3);
	}
	else if (StringsEqual(Tag, "opac_scale"))
	{ 
		return ReadFloatValue(Value, OpacityScale);
	}
	else if (StringsEqual(Tag, "opac_shift"))
	{
		return ReadFloatValue(Value, OpacityShift);
	}
	UnrecognizedTag();
	return false;
}

bool XML_SW_Texture_Parser::AttributesDone()
{
	SW_Texture *sw_texture = SW_Texture_Extras::instance()->AddTexture(BUILD_DESCRIPTOR(Collection, Bitmap));
	sw_texture->descriptor(BUILD_DESCRIPTOR(Collection, Bitmap));
	sw_texture->opac_type(OpacityType);
	sw_texture->opac_scale(OpacityScale);
	sw_texture->opac_shift(OpacityShift);
	return true;
}

static XML_SW_Texture_Parser SW_Texture_Parser;

XML_ElementParser *SW_Texture_GetParser()
{
	return &SW_Texture_Parser;
}

static XML_ElementParser SW_Texture_Extras_Parser("software");

XML_ElementParser *SW_Texture_Extras_GetParser()
{
	SW_Texture_Extras_Parser.AddChild(SW_Texture_GetParser());
	return &SW_Texture_Extras_Parser;
}