//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: 
//
//===========================================================================//

#include <tier0/platform.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>
#include "bitmap/float_bm.h"
#include <tier2/tier2.h>
#include "bitmap/imageformat.h"
#include "bitmap/tgaloader.h"
#include "tier1/strtools.h"
#include "filesystem.h"


#define SQ(x) ((x)*(x))

// linear interpolate between 2 control points (L,R)


inline float LinInterp(float frac, float L, float R)
{
	return (((R-L) * frac) + L);
}

// bilinear interpolate between 4 control points (UL,UR,LL,LR)

inline float BiLinInterp(float Xfrac, float Yfrac, float UL, float UR, float LL, float LR)
{
	float iu = LinInterp(Xfrac, UL, UR);
	float il = LinInterp(Xfrac, LL, LR);

	return( LinInterp(Yfrac, iu, il) );
}

FloatBitMap_t::FloatBitMap_t(int width, int height)
{
	RGBAData=0;
	AllocateRGB(width,height);
}

FloatBitMap_t::FloatBitMap_t(FloatBitMap_t const *orig)
{
	RGBAData=0;
	AllocateRGB(orig->Width,orig->Height);
	memcpy(RGBAData,orig->RGBAData,Width*Height*sizeof(float)*4);
}

static char GetChar(FileHandle_t &f)
{
	char a;
	g_pFullFileSystem->Read(&a,1,f);
	return a;
}

static int GetInt(FileHandle_t &f)
{
	char buf[100];
	char *bout=buf;
	for(;;)
	{
		char c=GetChar(f);
		if ((c<'0') || (c>'9'))
			break;
		*(bout++)=c;
	}
	*(bout++)=0;
	return atoi(buf);

}

#define PFM_MAX_XSIZE 2048

bool FloatBitMap_t::LoadFromPFM(char const *fname)
{
	FileHandle_t f = g_pFullFileSystem->Open(fname, "rb");
	if (f)
	{
		if( ( GetChar(f) == 'P' ) && (GetChar(f) == 'F' ) && ( GetChar(f) == '\n' ))
		{
			Width=GetInt(f);
			Height=GetInt(f);

			// eat crap until the next newline
			while( GetChar(f) != '\n')
			{
			}

			//			printf("file %s w=%d h=%d\n",fname,Width,Height);
			AllocateRGB(Width,Height);

			for( int y = Height-1; y >= 0; y-- )
			{
				float linebuffer[PFM_MAX_XSIZE*3];
				g_pFullFileSystem->Read(linebuffer,3*Width*sizeof(float),f);
				for(int x=0;x<Width;x++)
				{
					for(int c=0;c<3;c++)
					{
						Pixel(x,y,c)=linebuffer[x*3+c];
					}
				}
			}
		}
		g_pFullFileSystem->Close( f );	// close file after reading
	}
	return (RGBAData!=0);
}

bool FloatBitMap_t::WritePFM(char const *fname)
{
	FileHandle_t f = g_pFullFileSystem->Open(fname, "wb");

	if ( f )
	{
		g_pFullFileSystem->FPrintf(f,"PF\n%d %d\n-1.000000\n",Width,Height);
		for( int y = Height-1; y >= 0; y-- )
		{
			float linebuffer[PFM_MAX_XSIZE*3];
			for(int x=0;x<Width;x++)
			{
				for(int c=0;c<3;c++)
				{
					linebuffer[x*3+c]=Pixel(x,y,c);
				}
			}
			g_pFullFileSystem->Write(linebuffer,3*Width*sizeof(float),f);
		}
		g_pFullFileSystem->Close(f);

		return true;
	}

	return false;
}


float FloatBitMap_t::InterpolatedPixel(float x, float y, int comp) const
{
	int Top= floor(y);
	float Yfrac= y - Top;
	int Bot= min(Height-1,Top+1);
	int Left= floor(x);
	float Xfrac= x - Left;
	int Right= min(Width-1,Left+1);
	return
		BiLinInterp(Xfrac, Yfrac, 
		Pixel(Left, Top, comp),
		Pixel(Right, Top, comp),
		Pixel(Left, Bot, comp),
		Pixel(Right, Bot, comp));

}

//-----------------------------------------------------------------
// resize (with bilinear filter) truecolor bitmap in place

void FloatBitMap_t::ReSize(int NewWidth, int NewHeight)
{
	float XRatio= (float)Width / (float)NewWidth;
	float YRatio= (float)Height / (float)NewHeight;
	float SourceX, SourceY, Xfrac, Yfrac;
	int Top, Bot, Left, Right;

	float *newrgba=new float[NewWidth * NewHeight * 4];

	SourceY= 0;
	for(int y=0;y<NewHeight;y++)
	{
		Yfrac= SourceY - floor(SourceY);
		Top= SourceY;
		Bot= SourceY+1;
		if (Bot>=Height) Bot= Height-1;
		SourceX= 0;
		for(int x=0;x<NewWidth;x++)
		{
			Xfrac= SourceX - floor(SourceX);
			Left= SourceX;
			Right= SourceX+1;
			if (Right>=Width) Right= Width-1;
			for(int c=0;c<4;c++)
			{
				newrgba[4*(y*NewWidth+x)+c] = BiLinInterp(Xfrac, Yfrac, 
					Pixel(Left, Top, c),
					Pixel(Right, Top, c),
					Pixel(Left, Bot, c),
					Pixel(Right, Bot, c));
			}
			SourceX+= XRatio;
		}
		SourceY+= YRatio;
	}

	delete[] RGBAData;
	RGBAData=newrgba;

	Width=NewWidth; 
	Height=NewHeight;
}

struct TGAHeader_t
{
	unsigned char 	id_length, colormap_type, image_type;
	unsigned char	colormap_index0,colormap_index1, colormap_length0,colormap_length1;
	unsigned char	colormap_size;
	unsigned char	x_origin0,x_origin1, y_origin0,y_origin1, width0, width1,height0,height1;
	unsigned char	pixel_size, attributes;
};

bool FloatBitMap_t::WriteTGAFile(char const *filename) const
{
	FileHandle_t f = g_pFullFileSystem->Open(filename, "wb");
	if (f)
	{
		TGAHeader_t myheader;
		memset(&myheader,0,sizeof(myheader));
		myheader.image_type=2;
		myheader.pixel_size=32;
		myheader.width0= Width & 0xff;
		myheader.width1= (Width>>8);
		myheader.height0= Height & 0xff;
		myheader.height1= (Height>>8);
		myheader.attributes=0x20;
		g_pFullFileSystem->Write(&myheader,sizeof(myheader),f);
		// now, write the pixels
		for(int y=0;y<Height;y++)
		{
			for(int x=0;x<Width;x++)
			{
				PixRGBAF fpix = PixelRGBAF( x, y );
				PixRGBA8 pix8 = PixRGBAF_to_8( fpix );

				g_pFullFileSystem->Write(&pix8.Blue,1,f);
				g_pFullFileSystem->Write(&pix8.Green,1,f);
				g_pFullFileSystem->Write(&pix8.Red,1,f);
				g_pFullFileSystem->Write(&pix8.Alpha,1,f);
			}
		}
		g_pFullFileSystem->Close( f );	// close file after reading
		
		return true;
	}
	return false;
}


FloatBitMap_t::FloatBitMap_t(char const *tgafilename)
{
	RGBAData=0;

	// load from a tga or pfm
	if (Q_stristr(tgafilename, ".pfm"))
	{
		LoadFromPFM(tgafilename);
		return;
	}

	int width1, height1;
	ImageFormat imageFormat1;
	float gamma1;

	if( !TGALoader::GetInfo( tgafilename, &width1, &height1, &imageFormat1, &gamma1 ) )
	{
		printf( "error loading %s\n", tgafilename);
		exit( -1 );
	}
	AllocateRGB(width1,height1);

	uint8 *pImage1Tmp = 
		new uint8 [ImageLoader::GetMemRequired( width1, height1, 1, imageFormat1, false )];

	if( !TGALoader::Load( pImage1Tmp, tgafilename, width1, height1, imageFormat1, 2.2f, false ) )
	{
		printf( "error loading %s\n", tgafilename);
		exit( -1 );
	}
	uint8 *pImage1 = 
		new uint8 [ImageLoader::GetMemRequired( width1, height1, 1, IMAGE_FORMAT_ABGR8888, false )];

	ImageLoader::ConvertImageFormat( pImage1Tmp, imageFormat1, pImage1, IMAGE_FORMAT_ABGR8888, width1, height1, 0, 0 );

	for(int y=0;y<height1;y++)
	{
		for(int x=0;x<width1;x++)
		{
			for(int c=0;c<4;c++)
			{
				Pixel(x,y,3-c)=pImage1[c+4*(x+(y*width1))]/255.0;
			}
		}
	}

	delete[] pImage1;
	delete[] pImage1Tmp;
}

FloatBitMap_t::~FloatBitMap_t(void)
{
	if (RGBAData)
		delete[] RGBAData;
}


FloatBitMap_t *FloatBitMap_t::QuarterSize(void) const
{
	// generate a new bitmap half on each axis

	FloatBitMap_t *newbm=new FloatBitMap_t(Width/2,Height/2);
	for(int y=0;y<Height/2;y++)
		for(int x=0;x<Width/2;x++)
		{
			for(int c=0;c<4;c++)
				newbm->Pixel(x,y,c)=((Pixel(x*2,y*2,c)+Pixel(x*2+1,y*2,c)+
				Pixel(x*2,y*2+1,c)+Pixel(x*2+1,y*2+1,c))/4);
		}
		return newbm;
}

FloatBitMap_t *FloatBitMap_t::QuarterSizeBlocky(void) const
{
	// generate a new bitmap half on each axis

	FloatBitMap_t *newbm=new FloatBitMap_t(Width/2,Height/2);
	for(int y=0;y<Height/2;y++)
		for(int x=0;x<Width/2;x++)
		{
			for(int c=0;c<4;c++)
				newbm->Pixel(x,y,c)=Pixel(x*2,y*2,c);
		}
		return newbm;
}

Vector FloatBitMap_t::AverageColor(void)
{
	Vector ret(0,0,0);
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
			for(int c=0;c<3;c++)
				ret[c]+=Pixel(x,y,c);
	ret*=1.0/(Width*Height);
	return ret;
}

float FloatBitMap_t::BrightestColor(void)
{
	float ret=0.0;
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
		{
			Vector v(Pixel(x,y,0),Pixel(x,y,1),Pixel(x,y,2));
			ret=max(ret,v.Length());
		}
		return ret;
}

template <class T> static inline void SWAP(T & a, T & b)
{
	T temp=a;
	a=b;
	b=temp;
}

void FloatBitMap_t::RaiseToPower(float power)
{
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
			for(int c=0;c<3;c++)
				Pixel(x,y,c)=pow((float)MAX(0.0,Pixel(x,y,c)),(float)power);

}

void FloatBitMap_t::Logize(void)
{
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
			for(int c=0;c<3;c++)
				Pixel(x,y,c)=log(1.0+Pixel(x,y,c));

}

void FloatBitMap_t::UnLogize(void)
{
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
			for(int c=0;c<3;c++)
				Pixel(x,y,c)=exp(Pixel(x,y,c))-1;
}


void FloatBitMap_t::Clear(float r, float g, float b, float alpha)
{
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
		{
			Pixel(x,y,0)=r;
			Pixel(x,y,1)=g;
			Pixel(x,y,2)=b;
			Pixel(x,y,3)=alpha;
		}
}

void FloatBitMap_t::ScaleRGB(float scale_factor)
{
	for(int y=0;y<Height;y++)
		for(int x=0;x<Width;x++)
			for(int c=0;c<3;c++)
				Pixel(x,y,c)*=scale_factor;
}

static int dx[4]={0,-1,1,0};
static int dy[4]={-1,0,0,1};

#define NDELTAS 4

void FloatBitMap_t::SmartPaste(FloatBitMap_t const &b, int xofs, int yofs, uint32 Flags)
{
	// now, need to make Difference map
	FloatBitMap_t DiffMap0(this);
	FloatBitMap_t DiffMap1(this);
	FloatBitMap_t DiffMap2(this);
	FloatBitMap_t DiffMap3(this);
	FloatBitMap_t *deltas[4]={&DiffMap0,&DiffMap1,&DiffMap2,&DiffMap3};
	for(int x=0;x<Width;x++)
		for(int y=0;y<Height;y++)
			for(int c=0;c<3;c++)
			{
				for(int i=0;i<NDELTAS;i++)
				{
					int x1=x+dx[i];
					int y1=y+dy[i];
					x1=MAX(0,x1);
					x1=MIN(Width-1,x1);
					y1=MAX(0,y1);
					y1=MIN(Height-1,y1);
					float dx1=Pixel(x,y,c)-Pixel(x1,y1,c);
					deltas[i]->Pixel(x,y,c)=dx1;
				}
			}
			for(int x=1;x<b.Width-1;x++)
				for(int y=1;y<b.Height-1;y++)
					for(int c=0;c<3;c++)
					{
						for(int i=0;i<NDELTAS;i++)
						{
							float diff=b.Pixel(x,y,c)-b.Pixel(x+dx[i],y+dy[i],c);
							deltas[i]->Pixel(x+xofs,y+yofs,c)=diff;
							if (Flags & SPFLAGS_MAXGRADIENT)
							{
								float dx1=Pixel(x+xofs,y+yofs,c)-Pixel(x+dx[i]+xofs,y+dy[i]+yofs,c);
								if (fabs(dx1)>fabs(diff))
									deltas[i]->Pixel(x+xofs,y+yofs,c)=dx1;
							}
						}
					}

					// now, calculate modifiability
					for(int x=0;x<Width;x++)
						for(int y=0;y<Height;y++)
						{
							float modify=0;
							if (
								(x>xofs+1) && (x<=xofs+b.Width-2) &&
								(y>yofs+1) && (y<=yofs+b.Height-2))
								modify=1;
							Alpha(x,y)=modify;
						}

						//   // now, force a fex pixels in center to be constant
						//   int midx=xofs+b.Width/2;
						//   int midy=yofs+b.Height/2;
						//   for(x=midx-10;x<midx+10;x++)
						//     for(int y=midy-10;y<midy+10;y++)
						//     {
						//       Alpha(x,y)=0;
						//       for(int c=0;c<3;c++)
						//         Pixel(x,y,c)=b.Pixel(x-xofs,y-yofs,c);
						//     }
						Poisson(deltas,6000,Flags);
}

void FloatBitMap_t::ScaleGradients(void)
{
	// now, need to make Difference map
	FloatBitMap_t DiffMap0(this);
	FloatBitMap_t DiffMap1(this);
	FloatBitMap_t DiffMap2(this);
	FloatBitMap_t DiffMap3(this);
	FloatBitMap_t *deltas[4]={&DiffMap0,&DiffMap1,&DiffMap2,&DiffMap3};
	double gsum=0.0;
	for(int x=0;x<Width;x++)
		for(int y=0;y<Height;y++)
			for(int c=0;c<3;c++)
			{
				for(int i=0;i<NDELTAS;i++)
				{
					int x1=x+dx[i];
					int y1=y+dy[i];
					x1=MAX(0,x1);
					x1=MIN(Width-1,x1);
					y1=MAX(0,y1);
					y1=MIN(Height-1,y1);
					float dx1=Pixel(x,y,c)-Pixel(x1,y1,c);
					deltas[i]->Pixel(x,y,c)=dx1;
					gsum+=fabs(dx1);
				}
			}
			// now, reduce gradient changes
			//  float gavg=gsum/(Width*Height);
			for(int x=0;x<Width;x++)
				for(int y=0;y<Height;y++)
					for(int c=0;c<3;c++)
					{
						for(int i=0;i<NDELTAS;i++)
						{
							float norml=1.1*deltas[i]->Pixel(x,y,c);
							//           if (norml<0.0)
							//             norml=-pow(-norml,1.2);
							//           else
							//             norml=pow(norml,1.2);
							deltas[i]->Pixel(x,y,c)=norml;
						}
					}

					// now, calculate modifiability
					for(int x=0;x<Width;x++)
						for(int y=0;y<Height;y++)
						{
							float modify=0;
							if (
								(x>0) && (x<Width-1) &&
								(y) && (y<Height-1))
							{
								modify=1;
								Alpha(x,y)=modify;
							}
						}

						Poisson(deltas,2200,0);
}



void FloatBitMap_t::MakeTileable(void)
{
	FloatBitMap_t rslta(this);
	// now, need to make Difference map
	FloatBitMap_t DiffMapX(this);
	FloatBitMap_t DiffMapY(this);
	// set each pixel=avg-pixel
	FloatBitMap_t *cursrc=&rslta;
	for(int x=1;x<Width-1;x++)
		for(int y=1;y<Height-1;y++)
			for(int c=0;c<3;c++)
			{
				DiffMapX.Pixel(x,y,c)=Pixel(x,y,c)-Pixel(x+1,y,c);
				DiffMapY.Pixel(x,y,c)=Pixel(x,y,c)-Pixel(x,y+1,c);
			}
			// initialize edge conditions
			for(int x=0;x<Width;x++)
			{
				for(int c=0;c<3;c++)
				{
					float a=0.5*(Pixel(x,Height-1,c)+=Pixel(x,0,c));
					rslta.Pixel(x,Height-1,c)=a;
					rslta.Pixel(x,0,c)=a;
				}
			}
			for(int y=0;y<Height;y++)
			{
				for(int c=0;c<3;c++)
				{
					float a=0.5*(Pixel(Width-1,y,c)+Pixel(0,y,c));
					rslta.Pixel(Width-1,y,c)=a;
					rslta.Pixel(0,y,c)=a;
				}
			}
			FloatBitMap_t rsltb(&rslta);
			FloatBitMap_t *curdst=&rsltb;

			// now, ready to iterate
			for(int pass=0;pass<10;pass++)
			{
				float error=0.0;
				for(int x=1;x<Width-1;x++)
					for(int y=1;y<Height-1;y++)
						for(int c=0;c<3;c++)
						{
							float desiredx=DiffMapX.Pixel(x,y,c)+cursrc->Pixel(x+1,y,c);
							float desiredy=DiffMapY.Pixel(x,y,c)+cursrc->Pixel(x,y+1,c);
							float desired=0.5*(desiredy+desiredx);
							curdst->Pixel(x,y,c)=FLerp(cursrc->Pixel(x,y,c),desired,0.5);
							error+=SQ(desired-cursrc->Pixel(x,y,c));
						}
						SWAP(cursrc,curdst);
			}
			// paste result
			for(int x=0;x<Width;x++)
				for(int y=0;y<Height;y++)
					for(int c=0;c<3;c++)
						Pixel(x,y,c)=curdst->Pixel(x,y,c);
}


void FloatBitMap_t::GetAlphaBounds(int &minx, int &miny, int &maxx,int &maxy)
{
	for(minx=0;minx<Width;minx++)
	{
		int y;
		for(y=0;y<Height;y++)
			if (Alpha(minx,y))
				break;
		if (y!=Height)
			break;
	}
	for(maxx=Width-1;maxx>=0;maxx--)
	{
		int y;
		for(y=0;y<Height;y++)
			if (Alpha(maxx,y))
				break;
		if (y!=Height)
			break;
	}
	for(miny=0;minx<Height;miny++)
	{
		int x;
		for(x=minx;x<=maxx;x++)
			if (Alpha(x,miny))
				break;
		if (x<maxx)
			break;
	}
	for(maxy=Height-1;maxy>=0;maxy--)
	{
		int x;
		for(x=minx;x<=maxx;x++)
			if (Alpha(x,maxy))
				break;
		if (x<maxx)
			break;
	}
}

void FloatBitMap_t::Poisson(FloatBitMap_t *deltas[4],
							int n_iters,
							uint32 flags                                  // SPF_xxx
							)
{
	int minx,miny,maxx,maxy;
	GetAlphaBounds(minx,miny,maxx,maxy);
	minx=MAX(1,minx);
	miny=MAX(1,miny);
	maxx=MIN(Width-2,maxx);
	maxy=MIN(Height-2,maxy);
	if (((maxx-minx)>25) && (maxy-miny)>25)
	{
		// perform at low resolution
		FloatBitMap_t *lowdeltas[NDELTAS];
		for(int i=0;i<NDELTAS;i++)
			lowdeltas[i]=deltas[i]->QuarterSize();
		FloatBitMap_t *tmp=QuarterSize();
		tmp->Poisson(lowdeltas,n_iters*4,flags);
		// now, propagate results from tmp to us
		for(int x=0;x<tmp->Width;x++)
			for(int y=0;y<tmp->Height;y++)
				for(int xi=0;xi<2;xi++)
					for(int yi=0;yi<2;yi++)
						if (Alpha(x*2+xi,y*2+yi))
						{
							for(int c=0;c<3;c++)
								Pixel(x*2+xi,y*2+yi,c)=
								FLerp(Pixel(x*2+xi,y*2+yi,c),tmp->Pixel(x,y,c),Alpha(x*2+xi,y*2+yi));
						}
						char fname[80];
						sprintf(fname,"sub%dx%d.tga",tmp->Width,tmp->Height);
						tmp->WriteTGAFile(fname);
						sprintf(fname,"submrg%dx%d.tga",tmp->Width,tmp->Height);
						WriteTGAFile(fname);
						delete tmp;
						for(int i=0;i<NDELTAS;i++)
							delete lowdeltas[i];
	}
	FloatBitMap_t work1(this);
	FloatBitMap_t work2(this);
	FloatBitMap_t *curdst=&work1;
	FloatBitMap_t *cursrc=&work2;
	// now, ready to iterate
	while(n_iters--)
	{
		float error=0.0;
		for(int x=minx;x<=maxx;x++)
		{
			for(int y=miny;y<=maxy;y++)
			{
				if (Alpha(x,y))
				{
					for(int c=0;c<3;c++)
					{
						float desired=0.0;
						for(int i=0;i<NDELTAS;i++)
							desired+=deltas[i]->Pixel(x,y,c)+cursrc->Pixel(x+dx[i],y+dy[i],c);
						desired*=(1.0/NDELTAS);
						//            desired=FLerp(Pixel(x,y,c),desired,Alpha(x,y));
						curdst->Pixel(x,y,c)=FLerp(cursrc->Pixel(x,y,c),desired,0.5);
						error+=SQ(desired-cursrc->Pixel(x,y,c));
					}
				}
				SWAP(cursrc,curdst);
			}
		}
	}
	// paste result
	for(int x=0;x<Width;x++)
	{
		for(int y=0;y<Height;y++)
		{
			for(int c=0;c<3;c++)
			{
				Pixel(x,y,c)=curdst->Pixel(x,y,c);
			}
		}
	}
}