//========= Copyright Valve Corporation, All rights reserved. ============//
//
// Purpose: 
//
// $NoKeywords: $
//
//===========================================================================//
#include <stdlib.h>
#include <stdio.h>
#include <direct.h>
#include "bitmap/tgaloader.h"
#include "mathlib/mathlib.h"
#include "tier2/tier2.h"
#include "tier1/utlbuffer.h"
#include "tier1/strtools.h"
#include "filesystem.h"

void Usage( void )
{
	printf( "Fuzzy compare of two tga files.\n\n" );
	printf( "Usage: tgamse src1.tga src2.tga \n" );
	printf( "Return: MSE\n\n" );
	printf( "Usage: tgamse src1.tga src2.tga threshhold \n" );
	printf( "Return: PASS\\FAIL\n" );
	exit( -1 );
}

int main( int argc, char **argv )
{
	if ( argc != 3 && argc != 4 )
	{
		Usage();
	}
	
	MathLib_Init( 2.2f, 2.2f, 0.0f, 2.0f );
	InitDefaultFileSystem();

	char pCurrentDirectory[MAX_PATH];
	if ( _getcwd( pCurrentDirectory, sizeof(pCurrentDirectory) ) == NULL )
	{
		fprintf( stderr, "Unable to get the current directory\n" );
		return -1;
	}
	Q_FixSlashes( pCurrentDirectory );
	Q_StripTrailingSlash( pCurrentDirectory );

	char pBuf[3][MAX_PATH];
	const char *pFileName[2];
	for ( int i = 0; i < 2; ++i )
	{
		if ( !Q_IsAbsolutePath( argv[i+1] ) )
		{
			Q_snprintf( pBuf[i], sizeof(pBuf[i]), "%s\\%s", pCurrentDirectory, argv[i+1] );
			pFileName[i] = pBuf[i];
		}
		else
		{
			pFileName[i] = argv[i+1];
		}
	}

	float fMSE = 10000.0f;

	if ( argc == 4 )
	{
		fMSE = atof(argv[3]);
	}

	int width1, height1;
	ImageFormat imageFormat1;
	float gamma1;

	CUtlBuffer buf1;
	if ( !g_pFullFileSystem->ReadFile( pFileName[0], NULL, buf1 ) )
	{
		fprintf( stderr, "%s not found\n", pFileName[0] );
		return -1;
	}

	if( !TGALoader::GetInfo( buf1, &width1, &height1, &imageFormat1, &gamma1 ) )
	{
		printf( "error loading %s\n", pFileName[0] );
		exit( -1 );
	}

	int width2, height2;
	ImageFormat imageFormat2;
	float gamma2;

	CUtlBuffer buf2;
	if ( !g_pFullFileSystem->ReadFile( pFileName[1], NULL, buf2 ) )
	{
		fprintf( stderr, "%s not found\n", pFileName[1] );
		return -1;
	}

	if( !TGALoader::GetInfo( buf2, &width2, &height2, &imageFormat2, &gamma2 ) )
	{
		printf( "error loading %s\n", pFileName[1] );
		exit( -1 );
	}

	if( width1 != width2 || height1 != height2 )
	{
		printf( "image dimensions different (%dx%d!=%dx%d): can't do diff for %s\n", 
			width1, height1, width2, height2, pFileName[0] );
		exit( -1 );
	}
#if 0
	// have to allow for different formats for now due to *.txt file screwup.
	if( imageFormat1 != imageFormat2 )
	{
		printf( "image format different (%s!=%s). . can't do diff for %s\n", 
			ImageLoader::GetName( imageFormat1 ), ImageLoader::GetName( imageFormat2 ), pDstFileName );
		exit( -1 );
	}
#endif
	if( gamma1 != gamma2 )
	{
		printf( "image gamma different (%f!=%f). . can't do diff for %s\n", gamma1, gamma2, pFileName[0] );
		exit( -1 );
	}

	unsigned char *pImage1Tmp = new unsigned char[ImageLoader::GetMemRequired( width1, height1, 1, imageFormat1, false )];
	unsigned char *pImage2Tmp = new unsigned char[ImageLoader::GetMemRequired( width2, height2, 1, imageFormat2, false )];

	buf1.SeekGet( CUtlBuffer::SEEK_HEAD, 0 );
	if( !TGALoader::Load( pImage1Tmp, buf1, width1, height1, imageFormat1, 2.2f, false ) )
	{
		printf( "error loading %s\n", pFileName[0] );
		exit( -1 );
	}
	
	buf2.SeekGet( CUtlBuffer::SEEK_HEAD, 0 );
	if( !TGALoader::Load( pImage2Tmp, buf2, width2, height2, imageFormat2, 2.2f, false ) )
	{
		printf( "error loading %s\n", pFileName[1] );
		exit( -1 );
	}

	unsigned char *pImage1 = new unsigned char[ImageLoader::GetMemRequired( width1, height1, 1, IMAGE_FORMAT_ABGR8888, false )];
	unsigned char *pImage2 = new unsigned char[ImageLoader::GetMemRequired( width2, height2, 1, IMAGE_FORMAT_ABGR8888, false )];
	ImageLoader::ConvertImageFormat( pImage1Tmp, imageFormat1, pImage1, IMAGE_FORMAT_ABGR8888, width1, height1, 0, 0 );
	ImageLoader::ConvertImageFormat( pImage2Tmp, imageFormat2, pImage2, IMAGE_FORMAT_ABGR8888, width2, height2, 0, 0 );

	int sizeInBytes = ImageLoader::SizeInBytes( IMAGE_FORMAT_ABGR8888 );
	float mse = 0.0f;
	for( int i = 0; i < width1 * height1 * sizeInBytes; i++ )
	{
		float d;
		d = ( float )( pImage2[i] - pImage1[i] );
		mse += ( d * d );		
	}

	mse /= ( float )( width1 * height1 * sizeInBytes );

	if ( argc == 3 )
	{		
		printf( "MSE=%f\n", mse );
	}
	else
	{
		if ( mse > fMSE )
		{
			printf( "FAIL" );
		}
		else 
		{
			printf( "PASS" );
		}
	}

	return 0;	
}