/*  This code is based on Apple's "GeekGameBoard" sample code, version 1.0.

    http://developer.apple.com/samplecode/GeekGameBoard/

    Copyright © 2007 Apple Inc. Copyright © 2008 Jens Alfke. All Rights Reserved.

    Redistribution and use in source and binary forms, with or without modification, are permitted

    provided that the following conditions are met:

    * Redistributions of source code must retain the above copyright notice, this list of conditions

      and the following disclaimer.

    * Redistributions in binary form must reproduce the above copyright notice, this list of

      conditions and the following disclaimer in the documentation and/or other materials provided

      with the distribution.

    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR

    IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 

    FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-

    BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES

    (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 

    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 

    CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 

    THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#import "GoGame.h"

#import "Grid.h"

#import "Piece.h"

#import "Dispenser.h"

#import "Stack.h"

#import "QuartzUtils.h"

#import "GGBUtils.h"

@implementation GoGame

- (id) initWithBoard: (GGBLayer*)board

{

    self = [super initWithBoard: board];

    if (self != nil) {

        [self setNumberOfPlayers: 2];

        [(Player*)[_players objectAtIndex: 0] setName: @"Red"];

        [(Player*)[_players objectAtIndex: 1] setName: @"White"];

        CGSize size = board.bounds.size;

        CGFloat boardSide = MIN(size.width,size.height);

        RectGrid *grid = [[RectGrid alloc] initWithRows: 9 columns: 9 

                                                  frame: CGRectMake(floor((size.width-boardSide)/2),

                                                                    floor((size.height-boardSide)/2),

                                                                    boardSide,boardSide)];

        _grid = grid;

        grid.backgroundColor = GetCGPatternNamed(@"Wood.jpg");

        grid.borderColor = kTranslucentLightGrayColor;

        grid.borderWidth = 2;

        grid.lineColor = kTranslucentGrayColor;

        grid.cellClass = [GoSquare class];

        [grid addAllCells];

        ((GoSquare*)[grid cellAtRow: 2 column: 2]).dotted = YES;

        ((GoSquare*)[grid cellAtRow: 6 column: 6]).dotted = YES;

        ((GoSquare*)[grid cellAtRow: 2 column: 6]).dotted = YES;

        ((GoSquare*)[grid cellAtRow: 6 column: 2]).dotted = YES;

        grid.usesDiagonals = grid.allowsMoves = grid.allowsCaptures = NO;

        [board addSublayer: grid];

        [grid release];

        CGRect gridFrame = grid.frame;

        CGFloat pieceSize = (int)grid.spacing.width & ~1;  // make sure it's even

        CGFloat captureHeight = gridFrame.size.height-4*pieceSize;

        _captured[0] = [[Stack alloc] initWithStartPos: CGPointMake(2*pieceSize,0)

                                               spacing: CGSizeMake(0,pieceSize)

                                          wrapInterval: floor(captureHeight/pieceSize)

                                           wrapSpacing: CGSizeMake(-pieceSize,0)];

        _captured[0].frame = CGRectMake(CGRectGetMinX(gridFrame)-3*pieceSize, 

                                          CGRectGetMinY(gridFrame)+3*pieceSize,

                                          2*pieceSize, captureHeight);

        _captured[0].zPosition = kPieceZ+1;

        [board addSublayer: _captured[0]];

        [_captured[0] release];

        _captured[1] = [[Stack alloc] initWithStartPos: CGPointMake(0,captureHeight)

                                               spacing: CGSizeMake(0,-pieceSize)

                                          wrapInterval: floor(captureHeight/pieceSize)

                                           wrapSpacing: CGSizeMake(pieceSize,0)];

        _captured[1].frame = CGRectMake(CGRectGetMaxX(gridFrame)+pieceSize, 

                                          CGRectGetMinY(gridFrame)+pieceSize,

                                          2*pieceSize, captureHeight);

        _captured[1].zPosition = kPieceZ+1;

        [board addSublayer: _captured[1]];

        [_captured[1] release];

        [self nextPlayer];

}

    return self;

}

- (Bit*) bitToPlaceInHolder: (id<BitHolder>)holder

{

    if( holder.bit != nil || ! [holder isKindOfClass: [GoSquare class]] )

        return nil;

    NSString *imageName = self.currentPlayer.index ?@"White Ball.png" :@"Red Ball.png";

    CGFloat pieceSize = (int)(_grid.spacing.width * 0.9) & ~1;  // make sure it's even

    Piece *stone = [[Piece alloc] initWithImageNamed: imageName scale: pieceSize];

    stone.owner = self.currentPlayer;

    return [stone autorelease];

}

- (BOOL) canBit: (Bit*)bit moveFrom: (id<BitHolder>)srcHolder to: (id<BitHolder>)dstHolder

{

    if( ! [dstHolder isKindOfClass: [Square class]] )

        return NO;

    Square *dst=(Square*)dstHolder;

    // There should be a check here for a "ko" (repeated position) ... exercise for the reader!

    // Check for suicidal move. First an easy check for an empty adjacent space:

    NSArray *neighbors = dst.neighbors;

    for( GridCell *c in neighbors )

        if( c.empty )

            return YES;                     // there's an empty space

    // If the piece is surrounded, check the neighboring groups' liberties:

    for( GridCell *c in neighbors ) {

        int nLiberties;

        [c getGroup: &nLiberties];

        if( c.bit.unfriendly ) {

            if( nLiberties <= 1 )

                return YES;             // the move captures, so it's not suicidal

        } else {

            if( nLiberties > 1 )

                return YES;             // the stone joins a group with other liberties

        }

    }

    return NO;

}

- (void) bit: (Bit*)bit movedFrom: (id<BitHolder>)srcHolder to: (id<BitHolder>)dstHolder

{

    Square *dst=(Square*)dstHolder;

    int curIndex = _currentPlayer.index;

    // Check for captured enemy groups:

    BOOL captured = NO;

    for( GridCell *c in dst.neighbors )

        if( c.bit.unfriendly ) {

            int nLiberties;

            NSSet *group = [c getGroup: &nLiberties];

            if( nLiberties == 0 ) {

                captured = YES;

                for( GridCell *capture in group )

                    [_captured[curIndex] addBit: capture.bit];  // Moves piece to POW camp!

            }

        }

    if( captured )

        PlaySound(@"Pop");

    [self nextPlayer];

}

// This sample code makes no attempt to detect the end of the game, or count score,

// both of which are rather complex to decide in Go.

@end