// from dietlibc

#include <stdarg.h>
#include <sys/types.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>
#include <stdio.h>

#include "dietstdio.h"

#define WANT_FLOATING_POINT_IN_SCANF
#define WANT_CHARACTER_CLASSES_IN_SCANF

#define A_GETC(fn)		(++consumed,(fn)->getch((fn)->data))
#define A_PUTC(c,fn)	(--consumed,(fn)->putch((c),(fn)->data))

int __v_scanf(struct arg_scanf* fn, const char *format, va_list arg_ptr)
{
	// printf("scanf: %s\n", format);
	unsigned int ch;	/* format act. char */
	int n=0;

	/* arg_ptr tmps */
#ifdef WANT_FLOATING_POINT_IN_SCANF
	double *pd;
	float  *pf;
#endif
#ifdef WANT_LONGLONG_SCANF
	long long *pll;
#endif
	long   *pl;
	short  *ph;
	int    *pi;
	char    *s;

	unsigned int consumed=0;

	/* get one char */
	int tpch= A_GETC(fn);

	//while ((tpch!=-1)&&(*format))
	while (*format)
	{
		ch=*format++;
		switch (ch) {
			/* end of format string ?!? */
		case 0: return 0;

			/* skip spaces ... */
		case ' ':
		case '\f':
		case '\t':
		case '\v':
		case '\n':
		case '\r':
			while((*format)&&(isspace(*format))) ++format;
			while(isspace(tpch)) tpch=A_GETC(fn);
			break;

			/* format string ... */
		case '%':
		{
			unsigned int _div=0;
			int width=-1;
			char flag_width=0;
			char flag_discard=0;
			char flag_half=0;
			char flag_long=0;
			char flag_longlong=0;

		in_scan:
			ch=*format++;
			if(ch!='n' && tpch==-1) goto err_out;
			switch (ch) {
				/* end of format string ?!? */
			case 0: return 0;

				/* check for % */
			case '%':
				if ((unsigned char)tpch != ch) goto err_out;
				tpch=A_GETC(fn);
				break;

				/* FLAGS */
			case '*':
				flag_discard=1;
				goto in_scan;
			case 'h':
				flag_half=1;
				goto in_scan;
			case 'l':
				if (flag_long) flag_longlong=1;
				flag_long=1;
				goto in_scan;
			case 'q':
			case 'L':
				flag_longlong=1;
				goto in_scan;

				/* WIDTH */
			case '0':
			case '1':
			case '2':
			case '3':
			case '4':
			case '5':
			case '6':
			case '7':
			case '8':
			case '9':
				width=strtol(format-1,&s,10);
				format=s;
				flag_width=1;
				goto in_scan;

				/* scan for integer / strtol reimplementation ... */
			case 'p':
			case 'X':
			case 'x':
				_div+=6;
			case 'd':
				_div+=2;
			case 'o':
				_div+=8;
			case 'u':
			case 'i':
			{
#ifdef WANT_LONGLONG_SCANF
				unsigned long long v=0;
#else
				unsigned long v=0;
#endif
				unsigned int consumedsofar;
				int neg=0;
				while(isspace(tpch)) tpch=A_GETC(fn);
				if (tpch=='-') {
					tpch=A_GETC(fn);
					neg=1;
				}

				if (tpch=='+') tpch=A_GETC(fn);

				if (tpch==-1) return n;
				consumedsofar=consumed;

				if (!flag_width) {
					if ((_div==16) && (tpch=='0')) goto scan_hex;
					if (!_div) {
						_div=10;
						if (tpch=='0') {
							_div=8;
						scan_hex:
							tpch=A_GETC(fn);
							if ((tpch|32)=='x') {
								tpch=A_GETC(fn);
								_div=16;
							}
						}
					}
				}
				while ((width)&&(tpch!=-1)) {
					register unsigned long c=tpch&0xff;
#ifdef WANT_LONGLONG_SCANF
					register unsigned long long d=c|0x20;
#else
					register unsigned long d=c|0x20;
#endif
					c=(d>='a'?d-'a'+10:c<='9'?c-'0':0xff);
					if (c>=_div) break;
					d=v*_div;
#ifdef WANT_LONGLONG_SCANF
					v=(d<v)?ULLONG_MAX:d+c;
#else
					v=(d<v)?ULONG_MAX:d+c;
#endif
					--width;
					tpch=A_GETC(fn);
				}

				if (consumedsofar==consumed) return n;

				if ((ch|0x20)<'p') {
#ifdef WANT_LONGLONG_SCANF
					register long long l=v;
					if (v>=-((unsigned long long)LLONG_MIN)) {
						l=(neg)?LLONG_MIN:LLONG_MAX;
					}
					else {
						if (neg) v*=-1;
					}
#else
					register long l=v;
					if (v>=-((unsigned long)LONG_MIN)) {
						l=(neg)?LONG_MIN:LONG_MAX;
					}
					else {
						if (neg) v*=-1;
					}
#endif
				}
				if (!flag_discard) {
#ifdef WANT_LONGLONG_SCANF
					if (flag_longlong) {
						pll=(long long *)va_arg(arg_ptr,long long*);
						*pll=v;
					} else
#endif
						if (flag_long) {
							pl=(long *)va_arg(arg_ptr,long*);
							*pl=v;
						} else if (flag_half) {
							ph=(short*)va_arg(arg_ptr,short*);
							*ph=v;
						} else {
							pi=(int *)va_arg(arg_ptr,int*);
							*pi=v;
						}
					if(consumedsofar<consumed) ++n;
				}
			}
			break;

			/* FIXME: return value of *scanf with ONE float maybe -1 instead of 0 */
#ifdef WANT_FLOATING_POINT_IN_SCANF
			/* floating point numbers */
			case 'e':
			case 'E':
			case 'f':
			case 'g':
			{
				double d=0.0;
				int neg=0;
				unsigned int consumedsofar;

				while(isspace(tpch)) tpch=A_GETC(fn);

				if (tpch=='-') {
					tpch=A_GETC(fn);
					neg=1;
				}
				if (tpch=='+') tpch=A_GETC(fn);

				consumedsofar=consumed;

				while (isdigit(tpch)) {
					d=d*10+(tpch-'0');
					tpch=A_GETC(fn);
				}
				if (tpch=='.') {
					double factor=.1;
					consumedsofar++;
					tpch=A_GETC(fn);
					while (isdigit(tpch)) {
						d=d+(factor*(tpch-'0'));
						factor/=10;
						tpch=A_GETC(fn);
					}
				}
				if (consumedsofar==consumed) return n;	/* error */
				if ((tpch|0x20)=='e') {
					int exp=0, prec=tpch;
					double factor=10;
					tpch=A_GETC(fn);
					if (tpch=='-') {
						factor=0.1;
						tpch=A_GETC(fn);
					} else if (tpch=='+') {
						tpch=A_GETC(fn);
					} else {
						d=0;
						if (tpch!=-1) A_PUTC(tpch,fn);
						tpch=prec;
						goto exp_out;
					}
					consumedsofar=consumed;
					while (isdigit(tpch)) {
						exp=exp*10+(tpch-'0');
						tpch=A_GETC(fn);
					}
					if (consumedsofar==consumed) return n;	/* error */
					while (exp) {	/* as in strtod: XXX: this introduces rounding errors */
						d*=factor; --exp;
					}
				}
			exp_out:
				if (!flag_discard) {
					if (flag_long) {
						pd=(double *)va_arg(arg_ptr,double*);
						*pd=d;
					} else {
						pf=(float *)va_arg(arg_ptr,float*);
						*pf=d;
					}
					++n;
				}
			}
			break;
#endif

			/* char-sequences */
			case 'c':
				if (!flag_discard) {
					s=(char *)va_arg(arg_ptr,char*);
					++n;
				}
				if (!flag_width) width=1;
				while (width && (tpch!=-1)) {
					if (!flag_discard) *(s++)=tpch;
					--width;
					tpch=A_GETC(fn);
				}
				break;

				/* string */
			case 's':
				if (!flag_discard) s=(char *)va_arg(arg_ptr,char*);
				while(isspace(tpch)) tpch=A_GETC(fn);
				if (tpch==-1) break;		/* end of scan -> error */
				while (width && (tpch!=-1) && (!isspace(tpch))) {
					if (!flag_discard) *s=tpch;
					if (tpch) ++s; else break;
					--width;
					tpch=A_GETC(fn);
				}
				if (!flag_discard) { *s=0; ++n; }
				break;

				/* consumed-count */
			case 'n':
				if (!flag_discard) {
					pi=(int *)va_arg(arg_ptr,int *);
//	    ++n;	/* in accordance to ANSI C we don't count this conversion */
					*pi=consumed-1;
				}
				break;

#ifdef WANT_CHARACTER_CLASSES_IN_SCANF
			case '[':
			{
				char cset[256];
				int flag_not=0;
				int flag_dash=0;
				memset(cset,0,sizeof(cset));
				ch=*format++;
				/* first char specials */
				if (ch=='^') {
					flag_not=1;
					ch=*format++;
				}
				if ((ch=='-')||(ch==']')) {
					cset[ch]=1;
					ch=*format++;
				}
				/* almost all non special chars */
				for (;(*format) && (*format!=']');++format) {
					if (flag_dash) {
						register unsigned char tmp=*format;
						for (;ch<=tmp;++ch) cset[ch]=1;
						flag_dash=0;
						ch=*format;
					}
					else if (*format=='-') flag_dash=1;
					else {
						cset[ch]=1;
						ch=*format;
					}
				}
				/* last char specials */
				if (flag_dash) cset['-']=1;
				else cset[ch]=1;

				/* like %c or %s */
				if (!flag_discard) {
					s=(char *)va_arg(arg_ptr,char*);
					++n;
				}
				while (width && (tpch>=0) && (cset[tpch]^flag_not)) {
					if (!flag_discard) *s=tpch;
					if (tpch) ++s; else break;
					--width;
					tpch=A_GETC(fn);
				}
				if (!flag_discard) *s=0;
				++format;
			}
			break;
#endif
			default:
				goto err_out;
			}
		}
		break;

		/* check if equal format string... */
		default:
			if ((unsigned char)tpch != ch) goto err_out;
			tpch=A_GETC(fn);
			break;
		}
	}

	/* maybe a "%n" follows */
	if(*format) {
		while(isspace(*format)) format++;
		if(format[0] == '%' && format[1] == 'n') {
			pi = (int *) va_arg(arg_ptr, int *);
			*pi = consumed - 1;
		}
	}

err_out:
	if (tpch < 0 && n == 0) return EOF;
	A_PUTC(tpch,fn);
	return n;
}