/*
  Comapre Args
  Copyright (C) 2006 Yangli Hector Yee

  This program is free software; you can redistribute it and/or modify it under the terms of the
  GNU General Public License as published by the Free Software Foundation; either version 2 of the License,
  or (at your option) any later version.

  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU General Public License for more details.

  You should have received a copy of the GNU General Public License along with this program;
  if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/

#include "CompareArgs.h"
#include "RGBAImage.h"
#include <stdio.h>

static const char* copyright =
"PerceptualDiff version 1.0, Copyright (C) 2006 Yangli Hector Yee\n\
PerceptualDiff comes with ABSOLUTELY NO WARRANTY;\n\
This is free software, and you are welcome\n\
to redistribute it under certain conditions;\n\
See the GPL page for details: http://www.gnu.org/copyleft/gpl.html\n\n";

static const char *usage =
"PeceptualDiff image1.tif image2.tif\n\n\
   Compares image1.tif and image2.tif using a perceptually based image metric\n\
   Options:\n\
\t-verbose       : Turns on verbose mode\n\
\t-fov deg       : Field of view in degrees (0.1 to 89.9)\n\
\t-threshold p	 : #pixels p below which differences are ignored\n\
\t-gamma g       : Value to convert rgb into linear space (default 2.2)\n\
\t-luminance l   : White luminance (default 100.0 cdm^-2)\n\
\t-output o.ppm  : Write difference to the file o.ppm\n\
\n\
\n Note: Input files can also be in the PNG format\
\n";

CompareArgs::CompareArgs()
{
    ImgA = NULL;
    ImgB = NULL;
    ImgDiff = NULL;
    Verbose = false;
    FieldOfView = 45.0f;
    Gamma = 2.2f;
    ThresholdPixels = 100;
    Luminance = 100.0f;
}

CompareArgs::~CompareArgs()
{
    if (ImgA) delete ImgA;
    if (ImgB) delete ImgB;
    if (ImgDiff) delete ImgDiff;
}

bool CompareArgs::Parse_Args(int argc, char **argv)
{
    cairo_surface_t *surface;
    if (argc < 3) {
	ErrorStr = copyright;
	ErrorStr += usage;
	return false;
    }
    for (int i = 0; i < argc; i++) {
	if (i == 1) {
	    surface = cairo_image_surface_create_from_png (argv[1]);
	    if (cairo_surface_status (surface))
	    {
		ErrorStr = "FAIL: Cannot open ";
		ErrorStr += argv[1];
		ErrorStr += " ";
		ErrorStr += cairo_status_to_string (cairo_surface_status (surface));
		ErrorStr += "\n";
		return false;
	    }
	    ImgA = new RGBACairoImage (surface);
	} else if (i == 2) {
	    surface = cairo_image_surface_create_from_png (argv[2]);
	    if (cairo_surface_status (surface))
	    {
		ErrorStr = "FAIL: Cannot open ";
		ErrorStr += argv[2];
		ErrorStr += " ";
		ErrorStr += cairo_status_to_string (cairo_surface_status (surface));
		ErrorStr += "\n";
		return false;
	    }
	    ImgB = new RGBACairoImage (surface);
	} else {
	    if (strstr(argv[i], "-fov")) {
		if (i + 1 < argc) {
		    FieldOfView = (float) atof(argv[i + 1]);
		}
	    } else if (strstr(argv[i], "-verbose")) {
		Verbose = true;
	    } else 	if (strstr(argv[i], "-threshold")) {
		if (i + 1 < argc) {
		    ThresholdPixels = atoi(argv[i + 1]);
		}
	    } else 	if (strstr(argv[i], "-gamma")) {
		if (i + 1 < argc) {
		    Gamma = (float) atof(argv[i + 1]);
		}
	    }else 	if (strstr(argv[i], "-luminance")) {
		if (i + 1 < argc) {
		    Luminance = (float) atof(argv[i + 1]);
		}
	    }else 	if (strstr(argv[i], "-output")) {
		if (i + 1 < argc) {
		    ImgDiff = new RGBAImage(ImgA->Get_Width(), ImgA->Get_Height(), argv[i+1]);
		}
	    }
	}
    } // i
    return true;
}

void CompareArgs::Print_Args()
{
    printf("Field of view is %f degrees\n", FieldOfView);
    printf("Threshold pixels is %d pixels\n", ThresholdPixels);
    printf("The Gamma is %f\n", Gamma);
    printf("The Display's luminance is %f candela per meter squared\n", Luminance);
}