/*
*    inc.c
*
*    Copyright (C) 2007  Pau Espin Pedrol (Sharwin_F) <pespin@espeweb.no-ip.com>
*
*    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 3 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, see <http://www.gnu.org/licenses/>
*/
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <gtk/gtk.h>
#include <math.h>


GtkWidget *crea_hbox(GtkWidget *parent) {

	GtkWidget *box = gtk_hbox_new(0,1);
	gtk_container_add(GTK_CONTAINER (parent), box);
	gtk_widget_show(box);
	
	return box;
}

gboolean delete_event( GtkWidget *widget,  GdkEvent  *event, gpointer   data )
{
	gtk_main_quit();
	return FALSE;
}


static int CalculaX(double a, double b, double c, double* x1, double* x2) {

	double dins = (b*b) + (-4)*a*c;
	
	if(dins<0)  {
		*x1 = dins;
		return 0;
	}

	else if(dins==0) {

		*x1 = *x2 = ( -1*b ) / ( 2*a );
		return 1;

	}

	double arrel = sqrt( dins );

		*x1 = ( -1*b + arrel ) / ( 2*a );

		*x2 = ( -1*b - arrel ) / ( 2*a );

	return 2;
}


static char* formata_double(double lf) {
	
	char *str = malloc( 32 );
	sprintf(str, "%lf", lf);
	int i , j;
	i = j = strlen(str)-1;
	
	for (i; i >= 0; i--) 
		if (str[i]=='.') 
		{
			str[i] = ','; 
			break;  //recorrem array agafant la posicio del punt = i
		}
	
	if(i!=0) //hi ha punt en algun lloc (i)
		for (j; j >= i && str[j]=='0'; j--)
		{
			str[j] = '\0';
			
			if(j!=0 && str[j-1]==',') //treiem punt si no hi han decimals
			{
				str[j-1] = '\0';
				break;		
			}
		}

	return str;
}


void Resol( GtkWidget** dades )
{
	double A, B, C;
	double x1, x2;
	char *s1, *s2;
	
	A = atof( gtk_entry_get_text (GTK_ENTRY (dades[0])) );
	
	B = atof( gtk_entry_get_text (GTK_ENTRY (dades[1])) );
	
	C = atof( gtk_entry_get_text (GTK_ENTRY (dades[2])) );
	
	int nX = CalculaX(A, B, C, &x1, &x2);
	s1 = formata_double(x1);
	s2 = formata_double(x2);
	
	/* Imprimim resultat */

	char strresult[90];

	if(nX==2)
		sprintf(strresult, "X1 = %s;\n\nX2 = %s;", s1, s2);
	else if (nX==1)
		sprintf(strresult, "\nX = %s;\n", s1);
	else    
		sprintf(strresult, "\nArrel negativa! [ sqrt(%s) ]\n No té solució", s1); //escribim l'interior l'arrel


	gtk_label_set_text( GTK_LABEL (dades[3]), strresult );

	free(s1); free(s2);

}