/*
 *
 * Interpreteur de ligne de commande
 *
 */

#include <stdio.h>
#include <limits.h>
#ifdef HAVE_CONFIG_H
#include "config.h"
#else
#define _(x) x
#endif
#include "interface.h"
#include "exceptions.h"
#include "pile.h"



typedef unsigned char op_t;

typedef struct operator_t {
	op_t op;
	int pri, func;
} operator_t;

op_t pile_operators[PILEOP_MAX];
int pile_nestedcall[PILECALL_MAX];

int pileop_pos = 0, pilecall_pos = 0;

operator_t operators[] = {
	{',', 0, OP_NEST},
	{'+', 2, OP_PLUS},
	{'-', 2, OP_MOINS},
	{'*', 3, OP_MUL},
	{'/', 3, OP_DIV},
	{'%', 3, OP_MOD},
	{'^', 4, OP_EXP},
	{'+' + 128, 5, OP_PLUS_UNARY},
	{'-' + 128, 5, OP_MOINS_UNARY},
	{'=', 1, OP_ASSIGN},
	{'(', 6, OP_FUNC_CALL},
	{'(' + 128, 6, OP_LPAREN},
	{255, -1, -1}
};

operator_t get_op(op_t op)
{
	int i;

	for (i = 0; operators[i].op != 255; i++) {
		if (operators[i].op == op)
			return operators[i];
	}

	return operators[i];
}

int get_pri(op_t op)
{
	return get_op(op).pri;
}

int get_func(op_t op)
{
	return get_op(op).func;
}

op_t get_last_op(void)
{
	if (pileop_pos)
		return pile_operators[pileop_pos - 1];
	else
		return -1;
}

op_t pop_op(void)
{
	if (pileop_pos)
		return pile_operators[--pileop_pos];
	return -1;
}

void push_op(op_t op)
{
	if (pileop_pos != PILEOP_MAX)
		pile_operators[pileop_pos++] = op;
	else
		exception(-1, _("Too many nested operators in expression.\n"));

}

int pop_call(void)
{
	if (pilecall_pos)
		fprintf(stderr, "Dépilement du dernier appel de fonction: %i\n",
			pile_nestedcall[pilecall_pos - 1]);
	return pile_nestedcall[--pilecall_pos];
	return -1;
}

void increment_call(void)
{
	if (pilecall_pos) {
		fprintf(stderr, "Incrément du dernier appel de fonction: %i\n",
			pile_nestedcall[pilecall_pos - 1]);
		if (pile_nestedcall[pilecall_pos - 1] != -1)
			pile_nestedcall[pilecall_pos - 1]++;
	}
}

int get_last_call(void)
{
	if (pilecall_pos)
		return pile_nestedcall[pilecall_pos - 1];
	return -1;
}

void push_call(int call)
{
	fprintf(stderr, "Empilement d'un appel de fonction: %i\n", call);
	if (pilecall_pos != PILECALL_MAX)
		pile_nestedcall[pilecall_pos++] = call;
	else
		exception(-1, _("Too many nested functions calls in expression.\n"));
}

char *getword(char *line, char *p)
{
	char o;

	do {
		if (*(line) != ' ') {
			o = *(p++) = *line;
			fprintf(stderr, "getword(): a trouvé le caractère '%c'\n", o);
		}
		line++;
	} while ((*line) && (*line != ')') && (*line != ';') && (get_func(*line) == -1)
		 && (get_func(o) == -1));
	*p = '\0';
	return line;
}

int parse_line(char *line)
{
	char buffer[BUFSIZ];
	op_t op;
	int got_unary = 128, nbrargs;

	fprintf(stderr, "Analyse de: \"%s\"...\n\n", line);
	while (*line) {
		line = getword(line, buffer);
		fprintf(stderr, "parse_line(): getword a trouvé le mot \"%s\"\n", buffer);
		if (get_func(buffer[0]) != -1) {
			fprintf(stderr, "Il s'agit d'un opérateur.\n");
			buffer[0] += got_unary;
			if (got_unary) {
				fprintf(stderr, "Opérateur de type unaire\n");
			}
			if (get_pri(buffer[0]) == -1) {
				if (got_unary) {
					exception(-1, _("Invalid unary operator"));
				} else {
					exception(-1, _("Invalid binary operator"));
				}
			}
			fprintf(stderr, "Priorité du dernier op: %i, priorité actu: %i\n",
				get_pri(get_last_op()), get_pri(buffer[0]));
			while (get_pri(get_last_op()) >= get_pri(buffer[0])
			       && ((get_last_op() & 127) != '(')) {
				fprintf(stderr,
					"Il y a un opérateur plus important sur la file.\n");
				act_pile(get_func(pop_op()));
				got_unary = 0;
				fprintf(stderr, "Priorité du dernier op: %i, priorité actu: %i\n",
					get_pri(get_last_op()), get_pri(buffer[0]));
			}
			fprintf(stderr, "Mise sur la file\n");
			if (buffer[0] == '(') {
				push_call(0);
			}
			if (buffer[0] == ',') {
				increment_call();
			} else
				push_op(buffer[0]);
			got_unary = 128;
		} else if ((buffer[0] == ';') || (buffer[0] == ')')) {
			fprintf(stderr, "Caractère spécial\n");
			switch (buffer[0]) {
			case ';':
				fprintf(stderr, "Vidage complet de la file (fin de commande).\n");
				while (pileop_pos) {
					op = pop_op();
					if (op == '(')
						exception(-1,
							  _
							  ("Parse error: too much left parenthesis"));
					act_pile(get_func(op));
				}
				break;
			case ')':
				fprintf(stderr, "Vidage de la file jusqu'à '(' car ')' trouvée.\n");
				while (1) {
					if (!pileop_pos)
						exception(-1,
							  _
							  ("Parse error: too much right parenthesis"));
					op = pop_op();
					if (((op & 127) == '('))
						break;
					act_pile(get_func(op));
				}
				if (op == '(') {
					nbrargs = pop_call();
					push_pile_int(nbrargs);
					act_pile(get_func(op));
				}
				got_unary = 0;
				break;
			}
		} else if (((buffer[0] >= 'A') && (buffer[0] <= 'Z'))
			   || ((buffer[0] >= 'a') && (buffer[0] <= 'z'))
			   || ((buffer[0] >= '0') && (buffer[0] <= '9')) || (buffer[0] == '_')) {
			fprintf(stderr, "Symbole.\n");
			push_pile(buffer);
			got_unary = 0;
			if (!get_last_call())
				increment_call();
		} else if (buffer[0]) {
			exception(-1, _("Invalid character"));
		}
	}
}