#include <merror.h>
#include <stdlib.h>

#include "lex.h"

/* init a empty string buffer */
inline void string_init(struct string *string)
{
	string->len = 0;
	string->size = 0;
	string->allocated = true;
	string->str = NULL;
}

/* free a string buffer */
inline void string_free(struct string *string)
{
	if (string->allocated && string->str)
		free(string->str);
}

/* clone a string buffer */
inline int string_clone(struct string *dst, const struct string *const src)
{
	dst->len = src->len;
	dst->size = src->len;
	dst->allocated = src->allocated;

	/// bss strings do not need to be
	/// malloced or copied
	if (src->allocated == false) {
		dst->str = src->str;
		return M_SUCCESS;
	}

	dst->str = malloc(sizeof(char) * src->len);
	if (dst->str == NULL) {
		PERROR("cannot alloc");
		return M_ERROR;
	}
	memcpy(dst->str, src->str, sizeof(char) * src->len);
	return M_SUCCESS;
}

/* moves a string */
inline void string_move(struct string *dst, struct string *src)
{
	dst->len = src->len;
	dst->size = src->len;
	dst->allocated = src->allocated;
	dst->str = src->str;

	// delete ptr in src
	src->str = NULL;
}

/* pushes a char onto a string */
int string_push(struct string *string, char c)
{
	if (string->len >= string->size) {
		int len = string->size ? string->size * 2 : 8;
		char *new = realloc(string->str, sizeof(char) + len);
		if (new == NULL) {
			PERROR("cannot realloc");
			return M_ERROR;
		}
		string->size = len;
		string->str = new;
	}
	string->str[string->len++] = c;
	return M_SUCCESS;
}

void string_bss(struct string *string, char *src)
{
	int len = strlen(src);
	string->str = src;
	string->len = len;
	string->size = len;
	string->allocated = false;
}