/*
 *
 * fonctions avancees sur les polynomes
 *
 */

#include "fonctions.h"
#include "pile.h"
#include "hash.h"
#include "main.h"
#include "scalaires.h"
#include "terminal.h"
#include "exceptions.h"
#include "polynom.h"
#include "interface.h"
#ifdef HAVE_CONFIG_H
#include "config.h"
#else
#define _(x) x
#endif

/*
 * Nous allons utiliser des pointeurs sur des fonctions. Voici donc les typedefs pour notre
 * structure... 
 */
typedef void (*func_name) (polynome arg1, polynome arg2, polynome arg3);

typedef struct func_t {
    func_name func;
    char *nom;
    int arite;
} func_t;

/*
 * ... et la structure elle-meme 
 */

static func_t func_table[] = {
    {deriv, "deriv", 1,},
    {derivn, "derivn", 2},
    {integ, "int", 1},
    {printvars, "printvars", 0},
    {help, "help", 0},
    {setdisplay, "setdisplay", 1},
    {reinit, "reinit", 0},
    {exit_call, "exit", 0},
    {setsmartprint, "setsmartprint", 1},
    {NULL, NULL, -1}
};

/*
 * On cherche simplement la routine a appeler parmi la table des fonctions 
 */

void appel_fonction(char *nom, int arite, polynome p1, polynome p2, polynome p3)
{
    int i = 0;
    int trouve = 0;

    while ((func_table[i].nom) && (!trouve)) {
	if (!strcmp(func_table[i].nom, nom))
	    trouve = 1;
	i++;
    }
    if (trouve) {
	if (func_table[i - 1].arite == arite) {
	    (*func_table[i - 1].func) (p1, p2, p3);
	} else {
	    exception(1, _("appel_fonction: incorrect arg number"));
	}
    } else {
	exception(1, _("appel_fonction: non-existent function"));
    }
}

/*
 * Fonction de derivation - rajoute le resultat sur la pile. 
 */

void deriv(polynome p1, polynome p2, polynome p3)
{
    polynome resultat = NULL, temp = NULL, t;

    while (p1) {
	if (p1->degre) {
	    t =
		ply_constr(rat_constr((p1->coef.num) * (p1->degre), p1->coef.denom),
			   (p1->degre - 1));
	    if (t) {
		if (resultat) {
		    temp->suiv = t;
		    temp = t;
		} else {
		    resultat = t;
		    temp = t;
		}
	    }
	}
	p1 = p1->suiv;
    }
    push_pile_poly(resultat);
}

/*
 * Fonction paresseuse 
 */

void derivn(polynome p1, polynome p2, polynome p3)
{
    pile_elem temp;
    int i;

    if (p1) {
	if ((p1->degre == 0) && (p1->coef.num > 0) && (p1->coef.denom == 1)) {
	    push_pile_poly(NULL);
	    for (i = 0; i < p1->coef.num; i++) {
		temp = pop_pile(1);
		ply_destruct(temp.poly);
		deriv(temp.poly, NULL, NULL);
	    }
	} else {
	    exception(1, _("derivn: invalid 2nd arg"));
	}
    } else {
	exception(1, _("derivn: invalid 2nd arg"));
    }
}

/*
 * Integration d'un polynome 
 */

void integ(polynome p1, polynome p2, polynome p3)
{
    polynome resultat = NULL, temp = NULL, t;

    while (p1) {
	t =
	    ply_constr(rat_constr((p1->coef.num), (p1->coef.denom) * (p1->degre + 1)),
		       (p1->degre + 1));
	if (t) {
	    if (resultat) {
		temp->suiv = t;
		temp = t;
	    } else {
		resultat = t;
		temp = t;
	    }
	}
	p1 = p1->suiv;
    }
    push_pile_poly(resultat);
}

/*
 * Quelques fonctions explicites... 
 */

void printvars(polynome p1, polynome p2, polynome p3)
{
    AfficheTableau(variables);
}

void help(polynome p1, polynome p2, polynome p3)
{
    printf(_("Available functions:\n"
	     ". deriv(p); first derivative of p\n"
	     ". derivn(p, n); nth derivative of p\n"
	     ". integ(p); primitive of p\n"
	     ". printvars(); print all variables\n"
	     ". help(); this help message\n"
	     ". setdisplay(n); set integer display format\n"
	     "\tn=1: DECIMAL, n=2: HEXA\n"
	     "\tn=3: OCTAL, n=4: FLOAT\n"
	     ". smartprint(bool); toggle smart print of polynoms\n"
	     ". reinit(); clear all variables\n" ". exit(); end program\n"));
}

void setdisplay(polynome p1, polynome p2, polynome p3)
{
    if (p1) {
	if ((!p1->degre)) {
	    switch (p1->coef.num) {
	    case 1:
		display = DEC;
		break;
	    case 2:
		display = HEX;
		break;
	    case 3:
		display = OCT;
		break;
	    case 4:
		display = FLT;
		break;
	    default:
		exception(1, _("setdisplay: invalid arg"));
	    }
	} else {
	    exception(1, _("setdisplay: invalid arg"));
	}
    } else {
	exception(1, _("setdisplay: invalid arg"));
    }
}

void reinit(polynome p1, polynome p2, polynome p3)
{
    DetruitTab(&variables);
    Initialise(&variables);
}

void exit_call(polynome p1, polynome p2, polynome p3)
{
    quit = 1;
}

void setsmartprint(polynome p1, polynome p2, polynome p3)
{
    if (p1) {
	if ((!p1->degre)) {
	    smartprint = p1->coef.num;
	} else {
	    exception(1, _("setsmartprint: invalid arg"));
	}
    } else {
	smartprint = 0;
    }
}