/*
	ShogiMove.java

	a shogi move

	97-feb-26 ped created
*/

import java.util.* ;

public class ShogiMove implements Enum_ShogiPieces
{
	//	allow package access to fields
	int fromfile ;		//	minus fromfile 	= piece to drop
	int	fromrank ;
	int tofile ;
	int torank ;		//	torank >=10		= promotion
	private String comment ;
	private String moveString ;

	ShogiMove( int fromfile, int fromrank, int tofile, int torank )
	{
		this.fromfile	= fromfile ;
		this.fromrank	= fromrank ;
		this.tofile 	= tofile ;
		this.torank		= torank ;
	}
	
	ShogiMove( String str, ShogiBoard board )
	{
		moveString = str ;

		boolean senteToMove = board.isSenteToMove( ) ;
		char pieceSym = str.charAt( 0 ) ;
		boolean promotedPiece = false ;
		if( pieceSym == '+' ) {
			pieceSym = str.charAt( 1 ) ;
			promotedPiece = true ;
			str = str.substring( 2 ) ;
		}
		else
			str = str.substring( 1 ) ;

		char pieceNames [ ] = { 'P', 'L', 'N', 'S', 'G', 'B', 'R', 'K' } ;
		int  pieces     [ ] = { SP,  SL,  SN,  SS,  SG,  SB,  SR,  SK  } ;

		int piece = EM ;
		for( int i = 0 ; i < 8 ; i ++ ) {
			if( pieceSym == pieceNames[ i ] ) {
				piece = pieces[ i ] ;
				if( ! board.isSenteToMove( ) )
					piece += 16 ;
				if( promotedPiece )
					piece +=  8 ;
			}
		}

		//	assert( piece != EM )
		
		boolean promotion = str.endsWith( "+" ) ;
		if( promotion || str.endsWith( "=" ) )
			str = str.substring( 0, str.length( ) - 1 ) ;

		fromfile = -1 ;
		fromrank = -1 ;

		boolean drop = false ;
		while( str.length( ) > 2 ) {
			char disambiguator = str.charAt( 0 ) ;
			if( disambiguator == '*' )
				drop = true ;
			else if( disambiguator != 'x' || disambiguator != '-' ) {
				if( Character.isDigit( disambiguator ) )
					fromfile = '9' - disambiguator ;
				else
					fromrank = 'i' - disambiguator ;
			}
			str = str.substring( 1 ) ;
		}

		torank = 'i' - str.charAt( 1 ) ;
		tofile = '9' - str.charAt( 0 ) ;

		if( ! drop ) {
			Vector moves = board.generateLegalMoves( piece ) ;
			for( int i = 0 ; i < moves.size( ) ; i ++ ) {
				ShogiMove move = ( ShogiMove ) moves.elementAt( i ) ;
				//	debug
				//	System.out.println( i + " " + move.fromfile + " " + move.fromrank
				//						  + " " + move.tofile	+ " " + move.torank ) ;
				//	debug
				if( tofile == move.tofile									&&
					torank == move.torank									&&
					( fromfile == -1 || fromfile == move.fromfile )			&&
					( fromrank == -1 || fromrank == move.fromrank ) ) {
						fromfile = move.fromfile ;
						fromrank = move.fromrank ;
						break ;
					}
			}
		}

		if( fromfile == -1 || fromrank == -1 )			//	failed to find move on list
			drop = true ;

		if( drop )
			fromfile = - piece ;
		
		else if( promotion )
			torank = torank + 10 ;
		
		//	debug
		//	System.out.println( moveString + " " + fromfile + " " + fromrank + " " + tofile + " " + torank ) ;
	}
	
	public void putComment( String str )
	{
		comment = str ;
	}

	public String getComment( )
	{
		return comment ;
	}

	public String getString( )
	{
		return moveString ;
	}	
}