//-----------------------------------------------------------------------------
// Copyright (c) 2013 GarageGames, LLC
// Portions Copyright (c) 2014 James S Urquhart
//
// 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.
//-----------------------------------------------------------------------------


#ifndef _PLATFORMGL_H_
#define _PLATFORMGL_H_

//#define DUMMY_GL

#ifdef DUMMY_GL

#include "platformWin32/gl_types.h"

#define GLAPI 
#define GLAPIENTRY

#include "platformWin32/gl_types.h"

#define GL_FUNCTION(fn_type,fn_name,fn_args, fn_value)  fn_type fn_name fn_args;
#include "platform/GLCoreFunc.h"
#include "platform/GLExtFunc.h"
#undef GL_FUNCTION

void gluOrtho2D( GLfloat, GLfloat, GLfloat, GLfloat );
GLint gluProject( GLdouble winx, GLdouble winy, GLdouble winz, const F64 *model, const F64 * proj, const GLint * vp, F64 * x, F64 * y, F64 * z );
GLint gluUnProject( GLdouble winx, GLdouble winy, GLdouble winz, const F64 *model, const F64 * proj, const GLint * vp, F64 * x, F64 * y, F64 * z );

#else

#include <GL/gl.h>
#include <GL/glext.h>

void gluOrtho2D( GLfloat, GLfloat, GLfloat, GLfloat );
GLint gluProject( GLdouble winx, GLdouble winy, GLdouble winz, const F64 *model, const F64 * proj, const GLint * vp, F64 * x, F64 * y, F64 * z );
GLint gluUnProject( GLdouble winx, GLdouble winy, GLdouble winz, const F64 *model, const F64 * proj, const GLint * vp, F64 * x, F64 * y, F64 * z );

#endif



#define MIN_RESOLUTION_X				1
#define MIN_RESOLUTION_Y				1
#define MIN_RESOLUTION_BIT_DEPTH		16
#define MIN_RESOLUTION_XY_STRING		"480 320"

#define EMSCRIPTEN_DEFAULT_RESOLUTION_X    1024
#define EMSCRIPTEN_DEFAULT_RESOLUTION_Y    768

#define EMSCRIPTEN_DEFAULT_RESOLUTION_BIT_DEPTH	32

#define EMSCRIPTEN_SCREEN_PORTRAIT			0
#define EMSCRIPTEN_SCREEN_LANDSCAPE			1
#define EMSCRIPTEN_SCREEN_RIGHT_SIDE_UP		3
#define EMSCRIPTEN_SCREEN_UPSIDE_DOWN		4


/// Allows outline mode drawing via a function pointer swapping trick.
/// Must be included AFTER all the OpenGL headers.
#include "platformEmscripten/EmscriptenOutlineGL.h"

// these are extensions for glAllocateVertexBufferEXT
#define GL_V12MTVFMT_EXT                      0x8702
#define GL_V12MTNVFMT_EXT                     0x8703
#define GL_V12FTVFMT_EXT                      0x8704
#define GL_V12FMTVFMT_EXT                     0x8705
//------------------------------------------------------------------------------

// make sure this is defined, as we need to use it when around.
// some versions of OSX only define the SGIS version ( same hexcode )
//#ifndef GL_CLAMP_TO_EDGE_EXT
//#define GL_CLAMP_TO_EDGE_EXT                     0x812F
//#endif

/// GL state information.
struct GLState
{
   bool suppARBMultitexture;
   bool suppEXTblendcolor;
   bool suppEXTblendminmax;
   bool suppPackedPixels;
   bool suppTexEnvAdd;
   bool suppLockedArrays;

   bool suppTextureEnvCombine;
   bool suppVertexArrayRange;
   bool suppFogCoord;
   bool suppEdgeClamp;

   bool suppTextureCompression;
   bool suppS3TC;
   bool suppFXT1;
   bool suppTexAnisotropic;

   bool suppPalettedTexture;
   bool suppVertexBuffer;
   bool suppSwapInterval;

   GLint maxFSAASamples;

   unsigned int triCount[4];
   unsigned int primCount[4];
   unsigned int primMode; // 0-3

   GLfloat maxAnisotropy;
   GLint   maxTextureUnits;
};

extern GLState gGLState;

extern bool gOpenGLDisablePT;
extern bool gOpenGLDisableCVA;
extern bool gOpenGLDisableTEC;
extern bool gOpenGLDisableARBMT;
extern bool gOpenGLDisableFC;
extern bool gOpenGLDisableTCompress;
extern bool gOpenGLNoEnvColor;
extern float gOpenGLGammaCorrection;
extern bool gOpenGLNoDrawArraysAlpha;

//------------------------------------------------------------------------------
/// Inline state getters for dgl
//------------------------------------------------------------------------------
inline void dglSetRenderPrimType(unsigned int type)
{
   gGLState.primMode = type;
}

inline void dglClearPrimMetrics()
{
   for(int i = 0; i < 4; i++)
      gGLState.triCount[i] = gGLState.primCount[i] = 0;
}

inline bool dglDoesSupportPalettedTexture()
{
   return gGLState.suppPalettedTexture && (gOpenGLDisablePT == false);
}

inline bool dglDoesSupportCompiledVertexArray()
{
   return gGLState.suppLockedArrays && (gOpenGLDisableCVA == false);
}

inline bool dglDoesSupportTextureEnvCombine()
{
   return gGLState.suppTextureEnvCombine && (gOpenGLDisableTEC == false);
}

inline bool dglDoesSupportARBMultitexture()
{
   return gGLState.suppARBMultitexture && (gOpenGLDisableARBMT == false);
}

inline bool dglDoesSupportEXTBlendColor()
{
   return gGLState.suppEXTblendcolor;
}

inline bool dglDoesSupportEXTBlendMinMax()
{
   return gGLState.suppEXTblendminmax;
}

inline bool dglDoesSupportVertexArrayRange()
{
   return gGLState.suppVertexArrayRange;
}

inline bool dglDoesSupportFogCoord()
{
   return gGLState.suppFogCoord && (gOpenGLDisableFC == false);
}

inline bool dglDoesSupportEdgeClamp()
{
   return gGLState.suppEdgeClamp;
}

inline bool dglDoesSupportTextureCompression()
{
   return gGLState.suppTextureCompression && (gOpenGLDisableTCompress == false);
}

inline bool dglDoesSupportS3TC()
{
   return gGLState.suppS3TC;
}

inline bool dglDoesSupportFXT1()
{
   return gGLState.suppFXT1;
}

inline bool dglDoesSupportTexEnvAdd()
{
   return gGLState.suppTexEnvAdd;
}

inline bool dglDoesSupportTexAnisotropy()
{
   return gGLState.suppTexAnisotropic;
}

inline bool dglDoesSupportVertexBuffer()
{
   return false;
}

inline GLfloat dglGetMaxAnisotropy()
{
   return gGLState.maxAnisotropy;
}

inline GLint dglGetMaxTextureUnits()
{
   if (dglDoesSupportARBMultitexture())
      return gGLState.maxTextureUnits;
   else
      return 1; 
}

//------------------------------------------------------------------------------
/// For radeon cards we can do fast FSAA mode switching.
/// Sets Full Scene Anti-Aliasing (FSAA) samples ( 1x, 2x, 4x ) via aglSetInteger()
//------------------------------------------------------------------------------
#define ATI_FSAA_LEVEL ((unsigned long)510)  
void dglSetFSAASamples(GLint aasamp);

#endif // _PLATFORMGL_H_