#pragma once


#include "ColorRgba.h"


class AlphaBitmap;
class RgbBitmap;
class RgbaBitmap;


class PvrTcDecoder
{
public:
  static void DecodeRgb4Bpp(ColorRgb<unsigned char>* result, int dim, const void* data);
  static void DecodeRgba4Bpp(ColorRgba<unsigned char>* result, int dim, const void* data);
};


class PvrTcEncoder
{
public:
    // Result must be large enough for bitmap.GetArea()/4 bytes
    static void EncodeAlpha2Bpp(void* result, const AlphaBitmap& bitmap);
    
    // Result must be large enough for bitmap.GetArea()/2 bytes
    static void EncodeAlpha4Bpp(void* result, const AlphaBitmap& bitmap);
    
    // Result must be large enough for bitmap.GetArea()/2 bytes
    static void EncodeRgb4Bpp(void* result, const RgbBitmap& bitmap);

    // Result must be large enough for bitmap.GetArea()/2 bytes
    static void EncodeRgb4Bpp(void* result, const RgbaBitmap& bitmap);

    // Result must be large enough for bitmap.GetArea()/2 bytes
    static void EncodeRgba4Bpp(void* result, const RgbaBitmap& bitmap);

private:
    static unsigned GetMortonNumber(int x, int y);
};


//============================================================================
//
// Modulation data specifies weightings of colorA to colorB for each pixel
//
// For mode = 0
//	00: 0/8
//  01: 3/8
//  10: 5/8
//  11: 8/8
//
// For mode = 1
//  00: 0/8
//  01: 4/8
//  10: 4/8 with alpha punchthrough
//  11: 8/8
//
// For colorIsOpaque=0
//  3 bits A
//  4 bits R
//  4 bits G
//  3/4 bits B
//
// For colorIsOpaque=1
//  5 bits R
//  5 bits G
//  4/5 bits B
//
//============================================================================


struct PvrTcPacket
{
    unsigned int    modulationData;
    unsigned        usePunchthroughAlpha : 1;
    unsigned        colorA          	 : 14;
    unsigned        colorAIsOpaque  	 : 1;
    unsigned        colorB        		 : 15;
    unsigned        colorBIsOpaque  	 : 1;
    
    ColorRgb<int> GetColorRgbA() const;
    ColorRgb<int> GetColorRgbB() const;
    ColorRgba<int> GetColorRgbaA() const;
    ColorRgba<int> GetColorRgbaB() const;
    
    void SetColorA(const ColorRgb<unsigned char>& c);
    void SetColorB(const ColorRgb<unsigned char>& c);

    void SetColorA(const ColorRgba<unsigned char>& c);
    void SetColorB(const ColorRgba<unsigned char>& c);
    
    static const unsigned char BILINEAR_FACTORS[16][4];
    static const unsigned char WEIGHTS[8][4];
};