/*

File: GoGame.m

Abstract: The Asian board game Go.

Version: 1.0

Disclaimer: IMPORTANT:  This Apple software is supplied to you by 

Apple Inc. ("Apple") in consideration of your agreement to the

following terms, and your use, installation, modification or

redistribution of this Apple software constitutes acceptance of these

terms.  If you do not agree with these terms, please do not use,

install, modify or redistribute this Apple software.

In consideration of your agreement to abide by the following terms, and

subject to these terms, Apple grants you a personal, non-exclusive

license, under Apple's copyrights in this original Apple software (the

"Apple Software"), to use, reproduce, modify and redistribute the Apple

Software, with or without modifications, in source and/or binary forms;

provided that if you redistribute the Apple Software in its entirety and

without modifications, you must retain this notice and the following

text and disclaimers in all such redistributions of the Apple Software. 

Neither the name, trademarks, service marks or logos of Apple Inc. 

may be used to endorse or promote products derived from the Apple

Software without specific prior written permission from Apple.  Except

as expressly stated in this notice, no other rights or licenses, express

or implied, are granted by Apple herein, including but not limited to

any patent rights that may be infringed by your derivative works or by

other works in which the Apple Software may be incorporated.

The Apple Software is provided by Apple on an "AS IS" basis.  APPLE

MAKES NO WARRANTIES, EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION

THE IMPLIED WARRANTIES OF NON-INFRINGEMENT, MERCHANTABILITY AND FITNESS

FOR A PARTICULAR PURPOSE, REGARDING THE APPLE SOFTWARE OR ITS USE AND

OPERATION ALONE OR IN COMBINATION WITH YOUR PRODUCTS.

IN NO EVENT SHALL APPLE BE LIABLE FOR ANY SPECIAL, INDIRECT, INCIDENTAL

OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

INTERRUPTION) ARISING IN ANY WAY OUT OF THE USE, REPRODUCTION,

MODIFICATION AND/OR DISTRIBUTION OF THE APPLE SOFTWARE, HOWEVER CAUSED

AND WHETHER UNDER THEORY OF CONTRACT, TORT (INCLUDING NEGLIGENCE),

STRICT LIABILITY OR OTHERWISE, EVEN IF APPLE HAS BEEN ADVISED OF THE

POSSIBILITY OF SUCH DAMAGE.

Copyright © 2007 Apple Inc. All Rights Reserved.

*/

#import "GoGame.h"

#import "Grid.h"

#import "Piece.h"

#import "Dispenser.h"

#import "Stack.h"

#import "QuartzUtils.h"

/**  WARNING: THIS CODE REQUIRES GARBAGE COLLECTION!

 **  This sample application uses Objective-C 2.0 garbage collection.

 **  Therefore, the source code in this file does NOT perform manual object memory management.

 **  If you reuse any of this code in a process that isn't garbage collected, you will need to

 **  add all necessary retain/release/autorelease calls, and implement -dealloc methods,

 **  otherwise unpleasant leakage will occur!

 **/

@implementation GoGame

- (void) x_createDispenser: (NSString*)imageName position: (CGPoint)position forPlayer: (unsigned)playerNo

{

    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.players objectAtIndex: playerNo];

    CGRect frame = {position, {1.5*pieceSize,1.5*pieceSize}};

    [_board addSublayer: [[Dispenser alloc] initWithPrototype: stone quantity: INT_MAX frame:frame]];

}    

- (id) initWithBoard: (CALayer*)board

{

    self = [super initWithBoard: board];

    if (self != nil) {

        [self setNumberOfPlayers: 2];

        CGSize size = board.bounds.size;

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

                                                  frame: CGRectMake((size.width-size.height+16)/2,8,

                                                                    size.height-16,size.height-16)];

        _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];

        CGRect gridFrame = grid.frame;

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

        [self x_createDispenser: @"Red Ball.png"

                      position: CGPointMake(CGRectGetMinX(gridFrame)-2*pieceSize, 

                                            CGRectGetMinY(gridFrame))

                     forPlayer: 0];

        [self x_createDispenser: @"White Ball.png"

                      position: CGPointMake(CGRectGetMaxX(gridFrame)+0.5*pieceSize,

                                            CGRectGetMaxY(gridFrame)-1.5*pieceSize)

                     forPlayer: 1];

        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[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]];

        [self nextPlayer];

}

    return self;

}

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

{

    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 )

        [[NSSound soundNamed: @"Pop"] play];

    [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