/*
 * image.c
 *
 * Handle images and image features
 *
 * Copyright © 2012 Deutsches Elektronen-Synchrotron DESY,
 *                  a research centre of the Helmholtz Association.
 *
 * Authors:
 *   2011-2012 Thomas White <taw@physics.org>
 *
 * This file is part of CrystFEL.
 *
 * CrystFEL 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 3 of the License, or
 * (at your option) any later version.
 *
 * CrystFEL 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 CrystFEL.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#define _ISOC99_SOURCE
#include <stdlib.h>
#include <assert.h>
#include <math.h>
#include <stdio.h>

#include "image.h"
#include "utils.h"

/**
 * SECTION:image
 * @short_description: Data structure representing an image
 * @title: Image
 * @section_id:
 * @see_also:
 * @include: "image.h"
 * @Image:
 *
 * The <structname>image</structname> structure represents an image, usually one
 * frame from a large series of diffraction patterns, which might be from the
 * same or different crystals.
 */


struct _imagefeaturelist
{
	struct imagefeature	*features;
	int			n_features;
};


void image_add_feature(ImageFeatureList *flist, double fs, double ss,
                       struct image *parent, double intensity, const char *name)
{
	if ( flist->features ) {
		flist->features = realloc(flist->features,
		                    (flist->n_features+1)
		                    *sizeof(struct imagefeature));
	} else {
		assert(flist->n_features == 0);
		flist->features = malloc(sizeof(struct imagefeature));
	}

	flist->features[flist->n_features].fs = fs;
	flist->features[flist->n_features].ss = ss;
	flist->features[flist->n_features].intensity = intensity;
	flist->features[flist->n_features].parent = parent;
	flist->features[flist->n_features].name = name;
	flist->features[flist->n_features].valid = 1;

	flist->n_features++;

}


ImageFeatureList *image_feature_list_new()
{
	ImageFeatureList *flist;

	flist = malloc(sizeof(ImageFeatureList));

	flist->n_features = 0;
	flist->features = NULL;

	return flist;
}


void image_feature_list_free(ImageFeatureList *flist)
{
	if ( !flist ) return;

	if ( flist->features ) free(flist->features);
	free(flist);
}


struct imagefeature *image_feature_closest(ImageFeatureList *flist,
                                           double fs, double ss,
                                           double *d, int *idx)
{
	int i;
	double dmin = +HUGE_VAL;
	int closest = 0;

	for ( i=0; i<flist->n_features; i++ ) {

		double ds;

		ds = distance(flist->features[i].fs, flist->features[i].ss,
		              fs, ss);

		if ( ds < dmin ) {
			dmin = ds;
			closest = i;
		}

	}

	if ( dmin < +HUGE_VAL ) {
		*d = dmin;
		*idx = closest;
		return &flist->features[closest];
	}

	*d = +INFINITY;
	return NULL;
}


int image_feature_count(ImageFeatureList *flist)
{
	if ( flist == NULL ) return 0;
	return flist->n_features;
}


struct imagefeature *image_get_feature(ImageFeatureList *flist, int idx)
{
	/* Sanity check */
	if ( flist == NULL ) return NULL;
	if ( idx >= flist->n_features ) return NULL;

	if ( flist->features[idx].valid == 0 ) return NULL;

	return &flist->features[idx];
}


void image_remove_feature(ImageFeatureList *flist, int idx)
{
	flist->features[idx].valid = 0;
}