#include <stdlib.h>
#include <string.h>
#include "lib.h"

#define ok(X)   \
	if (X == 0) \
		return;
#define okr(X)  \
	if (X == 0) \
		return (0);

int _length(String* str)
{
	okr(str);
	return (str->strlength);
}
String* _newstr(char* str)
{
	String* s;
	okr(str);
	s = (String*)salloc(sizeof(String));
	s->strcount = 1;
	s->strlength = strlen(str);
	s->strval = salloc(s->strlength + 1);
	strcpy(s->strval, str);
	return (s);
}
void _incstr(String* src)
{
	/* one more variable uses the string */
	ok(src);
	src->strcount++;
}
void _decstr(String* str)
{
	ok(str);
	/* Strings in ROM are initialized with this count */
	if (str->strcount == 9999)
		return;
	str->strcount--;
	if (str->strcount <= 0)
		_delstr(str);
}
void _strcpy(String* dst, String* src)
{
	ok(src);
	ok(dst);
	_decstr(dst);
	*dst = *src;
	_incstr(src);
}
void _delstr(String* src)
{
	ok(src);
	sfree(src->strval);
	sfree((char*)src);
}
String* _concat(String* s1, String* s2)
{
	String* s;
	int length;
	okr(s1);
	okr(s2);
	s = (String*)salloc(sizeof(String));
	s->strlength = _length(s1) + _length(s2);
	s->strval = salloc(s->strlength + 1);
	s->strcount = 1;
	strcpy(s->strval, s2->strval);
	strcat(s->strval, s1->strval);
	return (s);
}
int _strcomp(String* s1, String* s2)
{
	okr(s1);
	okr(s2);
	return (strcmp(s2->strval, s1->strval));
}

String* _left(int size, String* s)
{
	String* ns;
	int i;

	okr(s);
	if (size < 0 || size > s->strlength)
		error(3);
	ns = (String*)salloc(sizeof(String));
	ns->strval = salloc(size + 1);
	ns->strcount = 1;
	for (i = 0; i < size && s->strval[i]; i++)
		ns->strval[i] = s->strval[i];
	ns->strval[i] = 0;
	ns->strlength = i;
	return (ns);
}

String* _space(int d)
{
	String* s;
	int i, len;

	len = d;
	s = (String*)salloc(sizeof(String));
	s->strlength = len;
	s->strcount = 1;
	s->strval = salloc(len + 1);
	for (i = 0; i < len; i++)
		s->strval[i] = ' ';
	s->strval[i] = 0;
	return (s);
}

String* _strascii(void)
{
}
String* _string(double f, double d)
{
	int i, j;
	String* s;

	i = d;
	j = f;
	if (i < 0 || i > MAXSTRING)
		error(3);
	s = (String*)salloc(sizeof(String));
	s->strlength = i;
	s->strcount = 1;
	s->strval = salloc(i + 1);
	s->strval[i--] = 0;
	for (; i >= 0; i--)
		s->strval[i] = j;
	return (s);
}
void _midstmt(String* s2, int i1, int i2, String* s)
{
	int l;

	/*printf("mid called %d %d %s %s\n",i1,i2,s->strval, s2->strval);*/
	if (i2 < 0 || i1 < -1)
		error(3);
	if (s->strlength < i2 || s2->strlength < i1)
		error(3); /* source string too short */
	if (i1 == -1)
		i1 = s2->strlength;
	l = s->strlength - i2 + 1;
	if (i1 > l)
		i1 = l;
	strncpy(s->strval + i2 - 1, s2->strval, i1);
}
String* _mid(int i1, int i2, String* s)
{
	int l;
	String* s2;

	/*	printf("mid fcn called %d %d %s\n",i1,i2,s->strval);*/
	if (i2 < 0 || i1 < -1)
		error(3);
	if (i1 == -1)
		i1 = s->strlength;
	s2 = _newstr(s->strval);
	s2->strval[0] = 0;
	if (s->strlength < i2)
		return (s2); /* source string too short */
	l = s->strlength - i2 + 1;
	if (i1 > l)
		i1 = l;
	strncpy(s2->strval, s->strval + i2 - 1, i1);
	s2->strval[i1] = 0;
	return (s2);
}

String* _right(int length, String* str)
{
	String* s;
	int i;

	i = _length(str) - length;
	if (i < 0)
		i = 0;
	s = _newstr(str->strval + i);
	return (s);
}