/*
 * The great and wonderful alias driver by me ;)
 * pinkfish.
 */
static string *history;
static int hoffset, numoff;
static int in_alias_command;
static string ignore_history;

void    history_commands()
{
    add_action( "print_history", "hi*story" );
}

string  substitute_history( string arg )
{
    string  s1, s2;

    if( sscanf( arg, "%s^%s", s1, s2 ) != 2 )
	return arg;
    sscanf( s2, "%s^", s2 );
    if( hoffset )
	return replace( history[ hoffset - 1 ], s1, s2 );
    else
	return replace( history[ sizeof( history ) - 1 ], s1, s2 );
}

string  expand_history( string arg )
{
    int     num, i;
    string  s1, s2;

    if( arg[ 0 ] == '.' )
	if( hoffset )
	    return history[ hoffset - 1 ] + arg[ 1..strlen( arg ) ];
	else
	    return history[ sizeof( history ) - 1 ] + arg[ 1..strlen( arg ) ];
    if( sscanf( arg, "%d", num ) == 1 )
    {
	num = num % sizeof( history );
	if( num < 0 )
	{
	    num += hoffset;
	    if( num < 0 )
		num += sizeof( history );
	}
	return history[ num ];
    }
    for( i = hoffset - 1; i >= 0; i-- )
	if( stringp( history[ i ] ) )
	    if( sscanf( history[ i ], arg + "%s", s1 ) == 1 )
		return history[ i ];
    for( i = sizeof( history ) - 1; i > hoffset; i-- )
	if( stringp( history[ i ] ) )
	    if( sscanf( history[ i ], arg + "%s", s1 ) == 1 )
		return history[ i ];
    return arg;
}

void    ignore_from_history( string str )
{
    ignore_history = str;
}

void    add_history( string arg )
{
    int     i;

    if( ignore_history )
    {
	if( ignore_history == arg )
	{
	    ignore_history = 0;
	    return;
	}
	ignore_history = 0;
    }
    if( arg[ 0 ] == '.' || arg[ 0 ] == '^' )
	return;
    if( in_alias_command )
	return;
    if( !history )
    {
	history = allocate( 40 );
	numoff = -40;
    }
    history[ hoffset++ ] = query_verb() + arg;
    if( hoffset >= sizeof( history ) )
    {
	numoff += sizeof( history );
	hoffset = 0;
    }
}

int     print_history( string arg )
{
    int     i, from, to, num;

    if( this_player() != this_object() )
    {				/* a call */
	if( !interactive( this_player() ) )
	    return 0;
	if( !("secure/master"->query_lord( geteuid( this_player() ) )) )
	    return 0;
    }
    from = hoffset;
    num = sizeof( history );
    if( !arg )
	arg = "";
    if( sscanf( arg, "%d,%d", from, to ) == 2 )
    {
	num = to - from;
	if( num < 0 )
	{
	    from = from + num;
	    num = -num;
	}
    }
    else
	if( sscanf( arg, ",%d", to ) == 1 )
	{
	    from = hoffset + 1 + sizeof( history );
	    num = from - (to % sizeof( history )) + sizeof( history );
	}
	else
	    if( sscanf( arg, "%d,", from ) == 1 )
	    {
		from = from % sizeof( history );
		num = from - hoffset;
		if( num < 0 )
		    num += sizeof( history );
	    }
	    else
		if( sscanf( arg, "%d", num ) != 1 )
		    num = sizeof( history );
    from = from % sizeof( history );
    if( num > sizeof( history ) )
	num = sizeof( history );
    for( i = from; i < sizeof( history ); i++, num-- )
    {
	if( history[ i ] )
	    write( (i + numoff) + ": " + history[ i ] + "\n" );
	if( !num )
	    return 1;
    }
    for( i = 0; i < from; i++, num-- )
    {
	if( history[ i ] )
	    write( (i + numoff + sizeof( history )) + ": " + history[ i ] + "\n" );
	if( !num )
	    return 1;
    }
    return 1;
}