//
// Copyright 2006 Johannes Hofmann <Johannes.Hofmann@gmx.de>
//
// This software may be used and distributed according to the terms
// of the GNU General Public License, incorporated herein by reference.

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>

#include <gsl/gsl_multifit.h>

#include <Fl/Fl.H>

#include "OutputImage.H"
#include "Stitch.H"

#define MIN(A,B) ((A)<(B)?(A):(B))


static double pi_d = asin(1.0) * 2.0;
static double deg2rad = pi_d / 180.0;

Stitch::Stitch() {
	for (int i=0; i<MAX_PICS; i++) {
		gipf[i] = NULL;
		single_images[i] = NULL;
	}
	merged_image = NULL;
}

Stitch::~Stitch() {
	for (int i=0; i<MAX_PICS; i++) {
		if (gipf[i]) {
			delete(gipf[i]);
		} else {
			break;
		}
	}
}


int
Stitch::load_image(char *file) {
	for (int i=0; i<MAX_PICS; i++) {
		if (gipf[i] == NULL) {
			gipf[i] = new GipfelWidget(0, 0, 800, 600);
			if (gipf[i]->load_image(file) != 0) {
				delete gipf[i];
				gipf[i] = NULL;
			}
			break;
		}
	}

	return 0;
}

OutputImage*
Stitch::set_output(OutputImage *img) {
	OutputImage *ret = merged_image;
	merged_image = img;
	return ret;
}

OutputImage*
Stitch::set_output(const char *file, OutputImage *img) {
	OutputImage *ret = NULL;

	for (int i=0; i<MAX_PICS; i++) {
		if (gipf[i] != NULL) {
			const char *img_file = gipf[i]->get_image_filename();
			if (img_file && strcmp(file, img_file) == 0) {
				ret = single_images[i];
				single_images[i] = img;
				break;
			}
		}
	}

	return ret;
}

int
Stitch::vignette_calib(GipfelWidget::sample_mode_t m,
	int w, int h, double view_start, double view_end) {

	view_start = view_start * deg2rad;
	view_end = view_end * deg2rad;

	double step_view = (view_end - view_start) / w;
	uchar r, g, b;
	int y_off = h / 2;
	int merged_pixel_set;
	double radius = (double) w / (view_end -view_start);

	int max_samples = 10000, n_samples = 0;
	gsl_matrix *X, *cov;
	gsl_vector *yv,  *c;
	double chisq;

	X = gsl_matrix_alloc(max_samples, 2);
	yv = gsl_vector_alloc(max_samples);
	c = gsl_vector_alloc(2);
	cov = gsl_matrix_alloc (2, 2);

	if (merged_image) {
		merged_image->init(w, h);
	}

	for (int y=0; y<h; y++) {
		double a_nick = atan((double)(y_off - y)/radius);

		for (int x=0; x<w; x++) {
			double a_view;
			a_view = view_start + x * step_view;
			merged_pixel_set = 0;
			double l1 = 0.0, l2 = 0.0;
			double a1, a2;
			uchar c1[3], c2[3];

			for (int i=0; i<MAX_PICS; i++) {

				if (gipf[i] == NULL) {
					break;
				} else if (gipf[i]->get_pixel(m, a_view, a_nick,
						&c2[0], &c2[1], &c2[2]) == 0) {
					l2 = (double) c2[0] + (double) c2[1] + (double) c2[2];
					a2 = gipf[i]->get_angle_off(a_view, a_nick);

					if (l1 > 0.0) {

						if (n_samples < max_samples &&
							fabs(a1 - a2) > 0.02 &&
							c1[0] < 200 && c1[1] < 200 && c1[2] < 200 &&
							c2[0] < 200 && c2[1] < 200 && c2[2] < 200 &&
							fabs(((double) c1[1]) / ((double) c1[0]) -
								((double) c2[1]) / ((double) c2[0])) < 0.02 && 
							fabs(((double) c1[2]) / ((double) c1[0]) -
								((double) c2[2]) / ((double) c2[0])) < 0.02) {

							gsl_matrix_set(X, n_samples, 0, l2 *  a2 * a2 *a2 * a2 - l1 * a1 *a1 *a1 * a1);
							gsl_matrix_set(X, n_samples, 1, l2 * a2 * a2 - l1 * a1 * a1);
							gsl_vector_set(yv, n_samples, l1 - l2);
							n_samples++;

							if (merged_image) {
								double V1 = -0.57301, V2 = 0.85233;
								double d = fabs(V2 * (l2 * a2 * a2 - l1 * a1 * a1) + V1 * (l2 *  a2 * a2 *a2 - l1 * a1 * a1 *a1) - (l1 -l2)); 

								merged_image->set_pixel(x, (uchar) rint(d * 2), 0, 0);	
								merged_pixel_set++;
							}


						}
					}
						
					l1 = l2;
					a1 = a2;
					c1[0] = c2[0];
					c1[1] = c2[1];
					c1[2] = c2[2];

					if (!merged_pixel_set && merged_image) {
						merged_image->set_pixel(x, c1[0], c1[1], c1[2]);
					}
				}
			}
		}
		if (merged_image) {
			merged_image->next_line();
		}
	}

	if (merged_image) {
		merged_image->done();
	}

	gsl_multifit_linear_workspace * work 
           = gsl_multifit_linear_alloc (n_samples, 2);

	gsl_multifit_linear (X, yv, c, cov, &chisq, work);
         gsl_multifit_linear_free (work);

	fprintf(stderr, "===>  v1 %lf v2 %lf, (i %d)\n", 
		gsl_vector_get(c,0),gsl_vector_get(c,1), n_samples);

	return 0;
}


int
Stitch::resample(GipfelWidget::sample_mode_t m,
	int w, int h, double view_start, double view_end) {

	view_start = view_start * deg2rad;
	view_end = view_end * deg2rad;

	double step_view = (view_end - view_start) / w;
	uchar r, g, b;
	int y_off = h / 2;
	int merged_pixel_set;
	double radius = (double) w / (view_end -view_start);
	double V1 = 0.213895, V2 = 0.089561;

	if (merged_image) {
		merged_image->init(w, h);
	}
	for (int i=0; i<MAX_PICS; i++) {
		if (single_images[i]) {
			single_images[i]->init(w, h);
		}
	}

	for (int y=0; y<h; y++) {
		double a_nick = atan((double)(y_off - y)/radius);
		double a_max = 0.0;

		for (int x=0; x<w; x++) {
			double a_view;
			a_view = view_start + x * step_view;
			merged_pixel_set = 0;
			for (int i=0; i<MAX_PICS; i++) {
				if (gipf[i] == NULL) {
					break;
				} else if (gipf[i]->get_pixel(m, a_view, a_nick,
						&r, &g, &b) == 0) {
					double a2 = gipf[i]->get_angle_off(a_view, a_nick);
					double devign = ( 1 + a2 * a2 * V2 + a2*a2*a2*a2 * V1);

#if 1 
					r = (uchar) MIN(rint((double) r * devign), 255);
					g = (uchar) MIN(rint((double) g * devign), 255);
					b = (uchar) MIN(rint((double) b * devign), 255);
#else 

					r = (uchar) MIN(rint((double) 100 * devign), 255);
					g = (uchar) MIN(rint((double) 100 * devign), 255);
					b = (uchar) MIN(rint((double) 100 * devign), 255);
#endif


					if (single_images[i]) {
						single_images[i]->set_pixel(x, r, g, b);
					}
					if (!merged_pixel_set && merged_image) {
						merged_image->set_pixel(x, r, g, b);
						merged_pixel_set++;
					}
				}
			}
		}
		if (merged_image) {
			merged_image->next_line();
		}
		for (int i=0; i<MAX_PICS; i++) {
			if (single_images[i]) {
				single_images[i]->next_line();
			}
		}
	}

	if (merged_image) {
		merged_image->done();
	}
	for (int i=0; i<MAX_PICS; i++) {
		if (single_images[i]) {
			single_images[i]->done();
		}
	}

	return 0;
}