#include <stdio.h>
#include <stdlib.h>
#include "kernel.h"
#include <math.h>

void main()
{
	kernel k;

	k = new_kernel(3, 3);
	print_kernel(k);

	printf("\n");	

	make_laplacian_kernel_1(k);
	print_kernel(k);

	printf("\n");	

	k->values[1][1] = 34.0;
	print_kernel(k);

	printf("\n");	
}

kernel new_kernel(int wi, int he)
{
	kernel k;
	int i, j;

	printf("new_kernel called.\n");

	k = (kernel) malloc (sizeof(kernel_struct));

	if (wi % 2 == 0 || he % 2 == 0) 
	{
		if (wi % 2 == 0) wi--;
		if (he % 2 == 0) he--;

		printf("Kernel: dimensions must be odd.\n");
		printf("	using %d x %d\n", wi, he);
	}

	k -> w = wi;
	k -> h = he;
	k -> values = (float **) malloc (wi * sizeof(float *));

	for (i = 0; i < wi; i++)
	{
		(k -> values)[i] = (float *) malloc (he * sizeof(float));
	}

	for (i = 0; i < wi; i++)
	{
	    for (j = 0; j < he; j++)
	    {
		(k -> values)[i][j] = 0;
	    }
	}

	*(get_ptr_to_center(k)) = 1;

	return k;
}

void print_kernel(kernel k)
{
	int i, j;

	for (j = 0; j < k -> h; j++)
	{
	    for (i = 0; i < k -> w; i++)
	    {
		printf("%6.2f ", (k -> values)[i][j]);
	    }
	    printf("\n");
	}
}

void make_laplacian_kernel_1(kernel k)
{
	set_value(k, 0, 0, -1);
	set_value(k, 1, 0, -1);
	set_value(k, 2, 0, -1);
	set_value(k, 0, 1, -1);
	set_value(k, 1, 1,  8);
	set_value(k, 2, 1, -1);
	set_value(k, 0, 2, -1);
	set_value(k, 1, 2, -1);
	set_value(k, 2, 2, -1);
}

void make_laplacian_kernel_2(kernel k)
{
	set_value(k, 0, 0,  1);
	set_value(k, 1, 0, -2);
	set_value(k, 2, 0,  1);
	set_value(k, 0, 1, -2);
	set_value(k, 1, 1,  4);
	set_value(k, 2, 1, -2);
	set_value(k, 0, 2,  1);
	set_value(k, 1, 2, -2);
	set_value(k, 2, 2,  1);
}

float * get_ptr_to_center(kernel k)
{
	return &((k -> values)[(k->w)/2][(k->h)/2]);
}

float get_value(kernel k, int x, int y)
{
	return (k -> values)[x][y];
}

void set_value(kernel k, int x, int y, float in)
{
	(k -> values)[x][y] = in;
}

void apply_kernel_to_int_array(kernel k, int w, int h, int ** inarr, int *** outarr)
{
	int i, j;
	
	copy_int_array(w, h, inarr, outarr);
		
	for (i = 0; i < w; i++)
	{
	    for (j = 0; j < h; j++)
	    {
		(*outarr)[i][j] = apply_3_kernel_to_one_int_element(
			k, i, j, w, h, 0, 255, inarr);
	    }
	}
	
}

int apply_3_kernel_to_one_int_element(kernel k, int i, int j, 
	int W, int H, int min, int max, int ** inarr)
{
	int m, n, s, e, w, ne, se, nw, sw;
	float value;
	int intvalue;

	m  = get_from_array(i,   j,   W, H, inarr);
	n  = get_from_array(i,   j-1, W, H, inarr);
	s  = get_from_array(i,   j+1, W, H, inarr);
	e  = get_from_array(i+1, j,   W, H, inarr);
	w  = get_from_array(i-1, j,   W, H, inarr);
	ne = get_from_array(i+1, j-1, W, H, inarr);
	nw = get_from_array(i-1, j-1, W, H, inarr);
	se = get_from_array(i+1, j+1, W, H, inarr);
	sw = get_from_array(i+1, j-1, W, H, inarr);

	value = 0;
	value += get_value(k, 0, 0) * nw;
	value += get_value(k, 1, 0) * n;
	value += get_value(k, 2, 0) * ne;
	value += get_value(k, 0, 1) * w;
	value += get_value(k, 1, 1) * m;
	value += get_value(k, 2, 1) * e;
	value += get_value(k, 0, 2) * sw;
	value += get_value(k, 1, 2) * s;
	value += get_value(k, 2, 2) * se;

	intvalue = (int) value;

	if (intvalue < min) intvalue = min;
	if (intvalue > max) intvalue = max;	

	return intvalue;
}

void apply_kernel_to_char_array(kernel k, int w, int h, char ** inarr, char *** outarr)
{
	int i, j;
	
	copy_char_array(w, h, inarr, outarr);
		
	for (i = 0; i < w; i++)
	{
	    for (j = 0; j < h; j++)
	    {
		(*outarr)[i][j] = apply_3_kernel_to_one_char_element(
			k, i, j, w, h, 0, 255, inarr);
	    }
	}
	
}

int apply_3_kernel_to_one_char_element(kernel k, int i, int j, 
	int W, int H, int min, int max, char ** inarr)
{
	char m, n, s, e, w, ne, se, nw, sw;
	float value;
	int intvalue;

	m  = get_from_char_array(i,   j,   W, H, inarr);
	n  = get_from_char_array(i,   j-1, W, H, inarr);
	s  = get_from_char_array(i,   j+1, W, H, inarr);
	e  = get_from_char_array(i+1, j,   W, H, inarr);
	w  = get_from_char_array(i-1, j,   W, H, inarr);
	ne = get_from_char_array(i+1, j-1, W, H, inarr);
	nw = get_from_char_array(i-1, j-1, W, H, inarr);
	se = get_from_char_array(i+1, j+1, W, H, inarr);
	sw = get_from_char_array(i+1, j-1, W, H, inarr);

	value = 0;
	value += get_value(k, 0, 0) * nw;
	value += get_value(k, 1, 0) * n;
	value += get_value(k, 2, 0) * ne;
	value += get_value(k, 0, 1) * w;
	value += get_value(k, 1, 1) * m;
	value += get_value(k, 2, 1) * e;
	value += get_value(k, 0, 2) * sw;
	value += get_value(k, 1, 2) * s;
	value += get_value(k, 2, 2) * se;

	intvalue = (int) value;

	if (intvalue < min) intvalue = min;
	if (intvalue > max) intvalue = max;	

	return (char) intvalue;
}

int get_from_array(int i, int j, int w, int h, int ** inarr)
{
	int i2, j2;

	if (i < 0)   i2 = 1;
	if (i > w-1) i2 = w-2;

	if (j < 0)   j2 = 1;
	if (j > h-1) j2 = h-2;

	return inarr[i2][j2];
}

char get_from_char_array(int i, int j, int w, int h, char ** inarr)
{
	int i2, j2;

	if (i < 0)   
	   i2 = 1;
	else if (i > w-1) 
	   i2 = w-2;
	else
	   i2 = i;

	if (j < 0) 
	   j2 = 1;
	else if (j > h-1)
	   j2 = h-2;
	else 
	   j2 = j;

	return inarr[i2][j2];
}

void copy_int_array(int w, int h, int ** inarr, int *** outarr)
{
	int i, j;
	
	for (i = 0; i < w; i++)
	{
	    for (j = 0; j < h; j++)
	    {
		(*outarr)[i][j] = inarr[i][j];
	    }
	}
}

void copy_char_array(int w, int h, char ** inarr, char *** outarr)
{
	int i, j;
	
	for (i = 0; i < w; i++)
	{
	    for (j = 0; j < h; j++)
	    {
		(*outarr)[i][j] = inarr[i][j];
	    }
	}
}





/*
void unused()
{
	m = inarr[i][j];

	if (i == 0)
	{
	    if (j == 0)
	    {
		m  = inarr[0][0];
		e  = inarr[1][0];
		s  = inarr[0][1];
		se = inarr[1][1];

		n  = s;
		w  = e;
		ne = se;
		nw = se;
		sw = se;
	    }
	    else if (j == h-1)
	    {
		m  = inarr[0][h-1];
		n  = inarr[0][h-2];
		e  = inarr[1][h-1];
		ne = inarr[1][h-2];

		w  = e;
		s  = n;
		nw = ne;
		sw = ne;
		se = ne;
	    }
	    else
	    {
		m  = inarr[0][j];
		n  = inarr[0][j-1];
		s  = inarr[0][j+1];
		ne = inarr[1][j-1];
		e  = inarr[1][j];
		se = inarr[1][j+1];
	
		w  = e;
		nw = ne;
		sw = se;
	    }
	}
	else if (i == w-1)
	{
	    if (j == 0)
	    {
		m  = inarr[i][0];
		e  = inarr[1][0];
		s  = inarr[0][1];
		se = inarr[1][1];

		n  = s;
		w  = e;
		ne = se;
		nw = se;
		sw = se;
	    }
	    else if (j == h)
	    {
		m  = inarr[0][h];
		n  = inarr[0][h-1];
		e  = inarr[1][h];
		ne = inarr[1][h-1];

		w  = e;
		s  = n;
		nw = ne;
		sw = ne;
		se = ne;
	    }
	    else
	    {
		m  = inarr[0][j];
		n  = inarr[0][j-1];
		s  = inarr[0][j+1];
		ne = inarr[1][j-1];
		e  = inarr[1][j];
		se = inarr[1][j+1];
	
		w  = e;
		nw = ne;
		sw = se;
	    }
	}
}

*/