#include <stdarg.h>
#include <sys/types.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>

#include "dietstdio.h"

#define WANT_NULL_PRINTF
#define WANT_FLOATING_POINT_IN_PRINTF

static inline unsigned int skip_to(const char *format) {
	unsigned int nr;
	for (nr=0; format[nr] && (format[nr]!='%'); ++nr);
	return nr;
}

#define A_WRITE(fn,buf,sz)	((fn)->put((void*)(buf),(sz),(fn)->data))

static const char pad_line[2][16]= { "                ", "0000000000000000", };
static inline int write_pad(struct arg_printf* fn, int len, int padwith) {
	int nr=0;
	for (;len>15;len-=16,nr+=16) {
		A_WRITE(fn,pad_line[(padwith=='0')?1:0],16);
	}
	if (len>0) {
		A_WRITE(fn,pad_line[(padwith=='0')?1:0],(unsigned int)len); nr+=len;
	}
	return nr;
}

int __v_printf(struct arg_printf* fn, const char *format, va_list arg_ptr)
{
	int len=0;
#ifdef WANT_ERROR_PRINTF
	int _errno = errno;
#endif

	while (*format) {
		unsigned int sz = skip_to(format);
		if (sz) {
			A_WRITE(fn,format,sz); len+=sz;
			format+=sz;
		}
		if (*format=='%') {
			char buf[128];
			union { char*s; } u_str;
#define s u_str.s

			int retval;
			unsigned char ch, padwith=' ';

			char flag_in_sign=0;
			char flag_upcase=0;
			char flag_hash=0;
			char flag_left=0;
			char flag_space=0;
			char flag_sign=0;
			char flag_dot=0;
			signed char flag_long=0;

			unsigned int base;
			unsigned int width=0, preci=0;

			long number=0;
#ifdef WANT_LONGLONG_PRINTF
			long long llnumber=0;
#endif

			++format;
		inn_printf:
			switch(ch=*format++) {
			case 0:
				return -1;
				break;

				/* FLAGS */
			case '#':
				flag_hash=-1;
			case 'z':
				goto inn_printf;

			case 'h':
				--flag_long;
				goto inn_printf;
			case 'q':		/* BSD ... */
			case 'L':
				++flag_long; /* fall through */
			case 'l':
				++flag_long;
				goto inn_printf;

			case '-':
				flag_left=1;
				goto inn_printf;

			case ' ':
				flag_space=1;
				goto inn_printf;

			case '+':
				flag_sign=1;
				goto inn_printf;

			case '0':
			case '1':
			case '2':
			case '3':
			case '4':
			case '5':
			case '6':
			case '7':
			case '8':
			case '9':
				if(flag_dot) return -1;
				width=strtoul(format-1,(char**)&s,10);
				if (ch=='0' && !flag_left) padwith='0';
				format=s;
				goto inn_printf;

			case '*':
				width=va_arg(arg_ptr,int);
				goto inn_printf;

			case '.':
				flag_dot=1;
				if (*format=='*') {
					int tmp=va_arg(arg_ptr,int);
					preci=tmp<0?0:tmp;
					++format;
				} else {
					long int tmp=strtol(format,(char**)&s,10);
					preci=tmp<0?0:tmp;
					format=s;
				}
				goto inn_printf;

				/* print a char or % */
			case 'c':
				ch=(char)va_arg(arg_ptr,int);
			case '%':
				A_WRITE(fn,&ch,1); ++len;
				break;

#ifdef WANT_ERROR_PRINTF
				/* print an error message */
			case 'm':
				s=strerror(_errno);
				sz=strlen(s);
				A_WRITE(fn,s,sz); len+=sz;
				break;
#endif
				/* print a string */
			case 's':
				s=va_arg(arg_ptr,char *);
#ifdef WANT_NULL_PRINTF
				if (!s) s="(null)";
#endif
				sz = strlen(s);
				if (flag_dot && sz>preci) sz=preci;
				preci=0;
				flag_dot^=flag_dot;
				padwith=' ';

			print_out:
				{
					char *sign=s;
					int todo=0;
					int vs;
	
					if (! (width||preci) ) {
						A_WRITE(fn,s,sz); len+=sz;
						break;
					}
	
					if (flag_in_sign) todo=1;
					if (flag_hash>0)  todo=flag_hash;
					if (todo) {
						s+=todo;
						sz-=todo;
						width-=todo;
					}
	
					if (!flag_left) {
						if (flag_dot) {
							vs=preci>sz?preci:sz;
							len+=write_pad(fn,(signed int)width-(signed int)vs,' ');
							if (todo) {
								A_WRITE(fn,sign,todo);
								len+=todo;
							}
							len+=write_pad(fn,(signed int)preci-(signed int)sz,'0');
						} else {
							if (todo && padwith=='0') {
								A_WRITE(fn,sign,todo);
								len+=todo; todo=0;
							}
							len+=write_pad(fn,(signed int)width-(signed int)sz, padwith);
							if (todo) {
								A_WRITE(fn,sign,todo);
								len+=todo;
							}
						}
						A_WRITE(fn,s,sz); len+=sz;
					} else if (flag_left) {
						if (todo) {
							A_WRITE(fn,sign,todo);
							len+=todo;
						}
						len+=write_pad(fn,(signed int)preci-(signed int)sz, '0');
						A_WRITE(fn,s,sz); len+=sz;
						vs=preci>sz?preci:sz;
						len+=write_pad(fn,(signed int)width-(signed int)vs, ' ');
					} else {
						A_WRITE(fn,s,sz); len+=sz;
					}
					break;
				}

				/* print an integer value */
			case 'b':
				base=2;
				sz=0;
				goto num_printf;
			case 'p':
				flag_hash=2;
				flag_long=1;
				ch='x';
			case 'X':
				flag_upcase=(ch=='X');
			case 'x':
				base=16;
				sz=0;
				if (flag_hash) {
					buf[1]='0';
					buf[2]=ch;
					flag_hash=2;
					sz=2;
				}
				if (preci>width) width=preci;
				goto num_printf;
			case 'd':
			case 'i':
				flag_in_sign=1;
			case 'u':
				base=10;
				sz=0;
				goto num_printf;
			case 'o':
				base=8;
				sz=0;
				if (flag_hash) {
					buf[1]='0';
					flag_hash=1;
					++sz;
				}

			num_printf:
				s=buf+1;

				if (flag_long>0) {
#ifdef WANT_LONGLONG_PRINTF
					if (flag_long>1)
						llnumber=va_arg(arg_ptr,long long);
					else
#endif
						number=va_arg(arg_ptr,long);
				}
				else
					number=va_arg(arg_ptr,int);

				if (flag_in_sign) {
#ifdef WANT_LONGLONG_PRINTF
					if ((flag_long>1)&&(llnumber<0)) {
						llnumber=-llnumber;
						flag_in_sign=2;
					} else
#endif
						if (number<0) {
							number=-number;
							flag_in_sign=2;
						}
				}
				if (flag_long<0) number&=0xffff;
				if (flag_long<-1) number&=0xff;
#ifdef WANT_LONGLONG_PRINTF
				if (flag_long>1)
					retval = __lltostr(s+sz,sizeof(buf)-5,(unsigned long long) llnumber,base,flag_upcase);
				else
#endif
					retval = __ltostr(s+sz,sizeof(buf)-5,(unsigned long) number,base,flag_upcase);

				/* When 0 is printed with an explicit precision 0, the output is empty. */
				if (flag_dot && retval == 1 && s[sz] == '0') {
					if (preci == 0||flag_hash > 0) {
						sz = 0;
					}
					flag_hash = 0;
				} else sz += retval;

				if (flag_in_sign==2) {
					*(--s)='-';
					++sz;
				} else if ((flag_in_sign)&&(flag_sign || flag_space)) {
					*(--s)=(flag_sign)?'+':' ';
					++sz;
				} else flag_in_sign=0;

				goto print_out;

#ifdef WANT_FLOATING_POINT_IN_PRINTF
				/* print a floating point value */
			case 'f':
			case 'g':
			{
				int g=(ch=='g');
				double d=va_arg(arg_ptr,double);
				s=buf+1;
				if (width==0) width=1;
				if (!flag_dot) preci=6;
				if (flag_sign || d < +0.0) flag_in_sign=1;
	  
				sz=__dtostr(d,s,sizeof(buf)-1,width,preci);
	  
				if (flag_dot) {
					char *tmp;
					if ((tmp=strchr(s,'.'))) {
						if (preci || flag_hash) ++tmp;
						while (preci>0 && *++tmp) --preci;
						*tmp=0;
					} else if (flag_hash) {
						s[sz]='.';
						s[++sz]='\0';
					}
				}

				if (g) {
					char *tmp,*tmp1;	/* boy, is _this_ ugly! */
					if ((tmp=strchr(s,'.'))) {
						tmp1=strchr(tmp,'e');
						while (*tmp) ++tmp;
						if (tmp1) tmp=tmp1;
						while (*--tmp=='0') ;
						if (*tmp!='.') ++tmp;
						*tmp=0;
						if (tmp1) strcpy(tmp,tmp1);
					}
				}
	  
				if ((flag_sign || flag_space) && d>=0) {
					*(--s)=(flag_sign)?'+':' ';
					++sz;
				}
	  
				sz=strlen(s);
				flag_dot=0;
				flag_hash=0;
				goto print_out;
			}
#endif

			default:
				break;
			}
		}
	}
	return len;
}