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

#ifdef OS_ABAOS	
#include "kernel.h"
#endif

#ifdef OS_ABAOS
console_t *stdio_console = NULL;
#endif

static void print_string( const char *s );
static void print_char( const char c );
static void print_newline( void );

#ifdef OS_ABAOS
static void print_string( const char *s )
{
	if( stdio_console == NULL ) {
		kernel_panic( "stdio_console not set!" );
	}

	console_put_string( stdio_console, s );
}

static void print_char( const char c )
{
	if( stdio_console == NULL ) {
		kernel_panic( "stdio_console not set!" );
	}

	console_put_char( stdio_console, c );
}

static void print_newline( void )
{
	if( stdio_console == NULL ) {
		kernel_panic( "stdio_console not set!" );
	}

	console_put_newline( stdio_console );
}
#endif

#ifdef OS_LINUX
static void print_string( const char *s )
{
	syscall3( __NR_write, STDOUT_FILENO, (long)s, strlen( s ) );
}

static void print_char( const char c )
{
	char s[2]; s[0] = c;
	syscall3( __NR_write, STDOUT_FILENO, (long)s, 1 );
}

static void print_newline( void )
{
	char s[2]; s[0] = '\n';
	syscall3( __NR_write, STDOUT_FILENO, (long)s, 1 );
}
#endif

int puts( const char *s )
{
	print_string( s );
	print_newline( );

	return 1;
}

int printf( const char *format, ... )
{
	va_list args;
	
	va_start( args, format );
	int res = vprintf( format, args );
	va_end( args );
	
	return res;
}

int vprintf( const char *format, va_list args )
{
	const char *s = format;
	int n = 0;
	
	while( *s != '\0' ) {
		switch( *s ) {
			case '\n':
				print_newline( );
				n++;
				break;
			
			case '%':
				s++;
				if( *s == '\0' ) {
					print_string( "<truncated % found at end of format string>" );
					print_newline( );
					return -1;
				}
				
				switch( *s ) {
					case '%':
						print_char( '%' );
						break;
						
					case 'X': {
						char buf[19];
						itoa( va_arg( args, int ), (char *)buf, 16 );
						print_string( buf );
						n += strlen( buf );
						}
						break;
					
					case 'd': {
						char buf[19];
						itoa( va_arg( args, int ), (char *)buf, 10 );
						print_string( buf );
						n += strlen( buf );
						}
						break;

					case 'c':
						print_char( va_arg( args, int ) );
						break;
						
					case 's':
						print_string( va_arg( args, const char * ) );
						break;

					default:
						print_string( "<illegal format string %" );
						print_char( *s );
						print_string( ">" );
						print_newline( );
				}
				
				break;				
			
			default:
				print_char( *s );
				n++;
		}
		s++;
	}
	
	return n;
}

int snprintf( char *buf, size_t n, const char *format, ... )
{
	va_list args;
	
	va_start( args, format );
	int res = vsnprintf( buf, n, format, args );
	va_end( args );
	
	return res;
}

#define EMIT( x ) if( len < n ) { *buf = ( x ); buf++; *buf = '\0'; len++; }

#define APPEND_STRING( s, s2 ) \
	strlcat( s, s2, n - len ); \
	s += strlen( s2 ); \
	len += strlen( s2 ); \
	if( len < n ) { \
		*s = '\0'; \
	}

int vsnprintf( char *buf, size_t n, const char *format, va_list args )
{
	const char *s = format;
	int len = 0;

	*buf = '\0';	
	while( *s != '\0' && len < n ) {
		switch( *s ) {
			case '\n':
				EMIT( '\n' );
				break;
			
			case '%':
				s++;
				if( *s == '\0' ) {
					strlcpy( buf, "<truncated % found at end of format string>", n - len );
					strlcat( buf, "\n", n - len - 1 );
					return -1;
				}
				
				switch( *s ) {
					case '%':
						EMIT( '%' );
						break;
						
					case 'X': {
						char buf2[19];
						itoa( va_arg( args, int ), (char *)buf2, 16 );
						APPEND_STRING( buf, buf2 );
						}
						break;
					
					case 'd': {
						char buf2[19];
						itoa( va_arg( args, int ), (char *)buf2, 10 );
						APPEND_STRING( buf, buf2 );
						}
						break;

					case 'c': {
						char buf2[2];
						buf2[0] = (char)va_arg( args, int );
						buf2[1] = '\0';
						APPEND_STRING( buf, buf2 );
						}
						break;
						
					case 's': {
						const char *s = va_arg( args, const char * );
						APPEND_STRING( buf, s );
						}
						break;

					default: {
						APPEND_STRING( buf, "<illegal format string %" );
						char buf2[2];
						buf2[0] = (char)( *s );
						buf2[1] = '\0';
						APPEND_STRING( buf, buf2 );
						buf2[0] = '\n';
						APPEND_STRING( buf, buf2 );
						}
				}
				
				break;				
			
			default: {
				char buf2[2];
				buf2[0] = (char)( *s );
				buf2[1] = '\0';
				APPEND_STRING( buf, buf2 );
				}
		}
		s++;
	}
	
	return len;
}


#ifdef OS_ABAOS
void __stdio_set_console( console_t *console )
{
	stdio_console = console;
}
#endif