/* Copyright (c) 2010 Nokia Corporation and/or its subsidiary(-ies).

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and /or associated documentation files

 * (the "Materials "), to deal in the Materials without restriction,

 * including without limitation the rights to use, copy, modify, merge,

 * publish, distribute, sublicense, and/or sell copies of the Materials,

 * and to permit persons to whom the Materials are 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 Materials.

 *

 * THE MATERIALS ARE 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 MATERIALS OR

 * THE USE OR OTHER DEALINGS IN THE MATERIALS.

 *

 * Initial Contributors:

 * Nokia Corporation - initial contribution.

 *

 * Contributors:

 *

 * Description:

 *

 */

#include "GLESTexture.h"

#include "glesInternal.h"

GLESTexture::GLESTexture(unsigned int name) :

	m_name(name),

	m_numLevels(0),

	m_levels(NULL)

{

}

GLESTexture::~GLESTexture()

{

	delete[] m_levels;

}

bool GLESTexture::AllocateLevels(int numLevels)

{

	GLES_ASSERT(m_levels == NULL);

	m_numLevels = numLevels;

	m_levels = GLES_NEW GLESTextureLevel[numLevels];

	if(m_levels == NULL)

	{

		return false;

	}

	for(int i = 0; i < numLevels; i++)

	{

		// From desktop GL spec.

		m_levels[i].format = 1;

		m_levels[i].width = 0;

		m_levels[i].height = 0;

		m_levels[i].boundSurface = NULL;

	}

	return true;

}

GLESTextureLevel* GLESTexture::Level(int level)

{

	GLES_ASSERT(m_levels != NULL);

	GLES_ASSERT(level >= 0 && level < m_numLevels);

	return &m_levels[level];

}

void GLESTexture::SetLevel(int level, GLenum format, GLsizei width, GLsizei height)

{

	GLES_ASSERT(m_levels != NULL);

	GLES_ASSERT(level >= 0 && level < m_numLevels);

	m_levels[level].format = format;

	m_levels[level].width = width;

	m_levels[level].height = height;

}

void GLESTexture::GenerateMipmap()

{

	GLES_ASSERT(m_levels != NULL);

	const GLESTextureLevel& level_zero = m_levels[0];

	m_numLevels = glesLog2(GLES_MAX(level_zero.width, level_zero.height)) + 1;

	int width = level_zero.width;

	int height = level_zero.height;

	for(int level = 1; level < m_numLevels; level++)

	{

		if(width > 1) width /= 2;

		if(height > 1) height /= 2;

		GLES_ASSERT((width > 1 || height > 1) || level == m_numLevels - 1);

		m_levels[level].format = level_zero.format;

		m_levels[level].width = width;

		m_levels[level].height = height;

	}

}

bool glesIsValidCompressedFormat(GLenum format)

{

	switch(format)

	{

	case GL_PALETTE4_RGB8_OES:

	case GL_PALETTE4_RGBA8_OES:

	case GL_PALETTE4_R5_G6_B5_OES:

	case GL_PALETTE4_RGBA4_OES:

	case GL_PALETTE4_RGB5_A1_OES:

	case GL_PALETTE8_RGB8_OES:

	case GL_PALETTE8_RGBA8_OES:

	case GL_PALETTE8_R5_G6_B5_OES:

	case GL_PALETTE8_RGBA4_OES:

	case GL_PALETTE8_RGB5_A1_OES:

		return true;

	default:

		return false;

	}

}

GLenum glesMapCompressedToBaseFormat(GLenum format)

{

	switch(format)

	{

	case GL_PALETTE4_RGB8_OES:

	case GL_PALETTE4_R5_G6_B5_OES:

	case GL_PALETTE8_RGB8_OES:

	case GL_PALETTE8_R5_G6_B5_OES:

		return GL_RGB;

	case GL_PALETTE4_RGBA8_OES:

	case GL_PALETTE4_RGBA4_OES:

	case GL_PALETTE4_RGB5_A1_OES:

	case GL_PALETTE8_RGBA8_OES:

	case GL_PALETTE8_RGBA4_OES:

	case GL_PALETTE8_RGB5_A1_OES:

		return GL_RGBA;

	default:

		GLES_ASSERT(false);

	}

	// not reached

	return 0;

}

void* glesUncompressImage(int level, GLenum format, int width, int height, int imageSize, const void* data)

{

	const unsigned char* palette = static_cast<const unsigned char*>(data);

	int bitsPerPixel;

	int paletteEntrySize;

	switch(format)

	{

	case GL_PALETTE4_RGB8_OES:

		bitsPerPixel = 4;

		paletteEntrySize = 3;

		break;

	case GL_PALETTE4_RGBA8_OES:

		bitsPerPixel = 4;

		paletteEntrySize = 4;

		break;

	case GL_PALETTE4_R5_G6_B5_OES:

	case GL_PALETTE4_RGB5_A1_OES:

	case GL_PALETTE4_RGBA4_OES:

		bitsPerPixel = 4;

		paletteEntrySize = 2;

		break;

	case GL_PALETTE8_RGB8_OES:

		bitsPerPixel = 8;

		paletteEntrySize = 3;

		break;

	case GL_PALETTE8_RGBA8_OES:

		bitsPerPixel = 8;

		paletteEntrySize = 4;

		break;

	case GL_PALETTE8_R5_G6_B5_OES:

	case GL_PALETTE8_RGBA4_OES:

	case GL_PALETTE8_RGB5_A1_OES:

		bitsPerPixel = 8;

		paletteEntrySize = 2;

		break;

	default:

		GLES_ASSERT(false);

	}

	int numPaletteEntries = 2 << (bitsPerPixel - 1);

	const unsigned char* imageData = palette + numPaletteEntries * paletteEntrySize;

	// Skip to the correct mip level

	for(int i = 0; i < level; i++)

	{

		if(bitsPerPixel == 8)

		{

			imageData += width * height * bitsPerPixel / 8;

		}

		else

		{

			GLES_ASSERT(bitsPerPixel == 4);

			imageData += width * height * bitsPerPixel / 8 / 2;

		}

		width /= 2;

		height /= 2;

	}

	int bytesPerPixel;

	GLenum baseFormat = glesMapCompressedToBaseFormat(format);

	if(baseFormat == GL_RGB)

	{

		bytesPerPixel = 3;

	}

	else

	{

		GLES_ASSERT(baseFormat == GL_RGBA);

		bytesPerPixel = 4;

	}

	char* uncompressedData = GLES_NEW char[width * height * bytesPerPixel];

	if(uncompressedData == NULL)

	{

		return NULL;

	}

	// Don't go past the end of the data

	int pixelsPerByte = 8 / bitsPerPixel;

	int maxPixels = (static_cast<const unsigned char*>(data) + imageSize - imageData) * pixelsPerByte;

	int end = GLES_MIN(width * height, maxPixels);

	for(int i = 0; i < end; i++)

	{

		int index;

		if(bitsPerPixel == 4)

		{

			if(i & 1)

			{

				index = imageData[i / 2] & 15;

			}

			else

			{

				index = imageData[i / 2] >> 4;

			}

		}

		else

		{

			GLES_ASSERT(bitsPerPixel == 8);

			index = imageData[i];

		}

		int r, g, b, a;

		switch(format)

		{

		case GL_PALETTE4_RGB8_OES:

		case GL_PALETTE8_RGB8_OES:

			r = palette[index*3];

			g = palette[index*3+1];

			b = palette[index*3+2];

			break;

		case GL_PALETTE4_RGBA8_OES:

		case GL_PALETTE8_RGBA8_OES:

			r = palette[index*4];

			g = palette[index*4+1];

			b = palette[index*4+2];

			a = palette[index*4+3];

			break;

		case GL_PALETTE4_R5_G6_B5_OES:

		case GL_PALETTE8_R5_G6_B5_OES:

			r = palette[index*2+1] >> 3;

			r = (r << 3) | (r >> 2);

			g = ((palette[index*2+1] & 7) << 3) | (palette[index*2] >> 5);

			g = (g << 2) | (g >> 4);

			b = palette[index*2] & 0x1f;

			b = (b << 3) | (b >> 2);

			break;

		case GL_PALETTE4_RGBA4_OES:

		case GL_PALETTE8_RGBA4_OES:

			r = palette[index*2+1] >> 4;

			r |= (r << 4) | r;

			g = palette[index*2+1] & 0xf;

			g |= (g << 4) | g;

			b = palette[index*2] >> 4;

			b |= (b << 4) | b;

			a = palette[index*2] & 0xf;

			a |= (a << 4) | a;

			break;

		case GL_PALETTE4_RGB5_A1_OES:

		case GL_PALETTE8_RGB5_A1_OES:

			r = palette[index*2+1] >> 3;

			r = (r << 3) | (r >> 2);

			g = ((palette[index*2+1] & 7) << 2) | (palette[index*2] >> 6);

			g = (g << 3) | (g >> 2);

			b = (palette[index*2] >> 1) & 0x1f;

			b = (b << 3) | (b >> 2);

			a = (palette[index*2] & 1) ? 255 : 0;

			break;

		default:

			GLES_ASSERT(false);

		}

		if(baseFormat == GL_RGB)

		{

			uncompressedData[i*3+0] = r;

			uncompressedData[i*3+1] = g;

			uncompressedData[i*3+2] = b;

		}

		else

		{

			GLES_ASSERT(baseFormat == GL_RGBA);

			uncompressedData[i*4+0] = r;

			uncompressedData[i*4+1] = g;

			uncompressedData[i*4+2] = b;

			uncompressedData[i*4+3] = a;

		}

	}

	return uncompressedData;

}