/*
 *  Copyright © 2006-2016 SplinterGU (Fenix/Bennugd)
 *  Copyright © 2002-2006 Fenix Team (Fenix)
 *  Copyright © 1999-2002 José Luis Cebrián Pagüe (Fenix)
 *
 *  This file is part of Bennu - Game Development
 *
 *  This software is provided 'as-is', without any express or implied
 *  warranty. In no event will the authors be held liable for any damages
 *  arising from the use of this software.
 *
 *  Permission is granted to anyone to use this software for any purpose,
 *  including commercial applications, and to alter it and redistribute it
 *  freely, subject to the following restrictions:
 *
 *     1. The origin of this software must not be misrepresented; you must not
 *     claim that you wrote the original software. If you use this software
 *     in a product, an acknowledgment in the product documentation would be
 *     appreciated but is not required.
 *
 *     2. Altered source versions must be plainly marked as such, and must not be
 *     misrepresented as being the original software.
 *
 *     3. This notice may not be removed or altered from any source
 *     distribution.
 *
 */

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

#include "token.h"
#include "identifiers.h"
#include "compiler.h"

/* ---------------------------------------------------------------------- */
/* Gestor de identificadores                                              */
/* ---------------------------------------------------------------------- */

static identifier * identifier_hash[64] ;
static int          identifier_code = 1 ;
int                 identifier_count = 0 ;

int identifier_hash_value(const char * string)
{
	int t = 0 ;
	const char * ptr = string ;

/*	while (*ptr) t = (t << 1) | *ptr++ ; */
	while (*ptr) t = (t << 3) | ( (*ptr++) & 0x07 ) ; /* Mejor dispersion en el hashing */

	return (t & 63) ;
}

identifier * identifier_first()
{
	int n ;

	for (n = 0 ; n < 64 ; n++)
	{
		if (identifier_hash[n])
			return identifier_hash[n] ;
	}
	return 0 ;
}

identifier * identifier_next(identifier * id)
{
	int n ;

	if (id->next) return id->next ;

	n = identifier_hash_value(id->name) ;
	for (n++ ; n < 64 ; n++)
	{
		if (identifier_hash[n])
			return identifier_hash[n] ;
	}
	return 0 ;
}

void identifier_init()
{
	int i ;

	for (i = 0 ; i < 64 ; i++) identifier_hash[i] = 0 ;

	identifier_count = 0 ;
	identifier_code = 1 ;
}

void identifier_dump()
{
	int i, ii ;
	identifier * ptr ;

	printf("\n---- %d identifiers ----\n\n", identifier_count) ;
	for (i = 0 ; i < 64 ; i++)
	{
		ptr = identifier_hash[i] ;
		ii = 0;
		while (ptr)
		{
			ii++;
			printf("%4d: %-32s [%04d] [%3d]\n", ptr->code, ptr->name, i, ii) ;
			ptr = ptr->next ;
		}
	}
}

int identifier_add_as(const char * string, int code)
{
	int hash = identifier_hash_value(string) ;
	identifier * w = (identifier *)calloc(1, sizeof(identifier)) ;

	if (!w)
	{
		fprintf(stdout, "identifier_add: out of memory\n") ;
		exit(1);
	}

	w->name = strdup(string) ;
	if (!w->name)
	{
		fprintf(stdout, "identifier_add: out of memory\n") ;
		exit(1);
	}
	w->line = line_count ; /* Save First appearance */
	w->f = current_file ;  /* Save File info */
	w->code = code ;
	w->next = identifier_hash[hash] ;
	identifier_hash[hash] = w ;
	identifier_count++ ;

	return 1 ;
}

int identifier_add(const char * string)
{
	int code = identifier_code++ ;
	if (!identifier_add_as(string, code)) return 0 ;
	return code ;
}

int identifier_search(const char * string)
{
	int hash = identifier_hash_value(string) ;
	identifier * ptr = identifier_hash[hash] ;

	while (ptr)
	{
		if (!ptr->name) return 0;
		if (ptr->name[0] == *string)
		{
			if (strcmp(string, ptr->name) == 0) break ;
		}
		ptr = ptr->next ;
	}
	return ptr ? ptr->code : 0 ;
}

/* Return line for the identifier */
int identifier_line(int code)
{
    int i ;
	identifier * ptr ;

	for (i = 0 ; i < 64 ; i++)
	{
		ptr = identifier_hash[i] ;
		while (ptr)
		{
			if (ptr->code == code) {
				return ptr->line ;
			}
			ptr = ptr->next ;
		}
	}
	return 0 ;
}

/* Return file for the identifier */
int identifier_file(int code)
{
    int i ;
	identifier * ptr ;

	for (i = 0 ; i < 64 ; i++)
	{
		ptr = identifier_hash[i] ;
		while (ptr)
		{
			if (ptr->code == code) {
				return ptr->f ;
			}
			ptr = ptr->next ;
		}
	}
	return 0 ;
}

const char * identifier_name(int code)
{
	int i ;
	identifier * ptr ;

	for (i = 0 ; i < 64 ; i++)
	{
		ptr = identifier_hash[i] ;
		while (ptr)
		{
			if (ptr->code == code) {
				return ptr->name ;
			}
			ptr = ptr->next ;
		}
	}
	return 0 ;
}

int identifier_search_or_add(const char * string)
{
	int result ;

	result = identifier_search(string) ;
	return result ? result : identifier_add(string) ;
}

int identifier_next_code()
{
	return identifier_code ;
}

int identifier_is_basic_type(int id)
{
	return (
		id == identifier_int ||
		id == identifier_short ||
		id == identifier_char ||
		id == identifier_dword ||
		id == identifier_word ||
		id == identifier_byte ||
		id == identifier_signed ||
		id == identifier_unsigned ||
		id == identifier_float ||
		id == identifier_string
		);
}

int identifier_is_type(int id)
{
	return identifier_is_basic_type(id) || segment_by_name(id) != NULL;
}