/*

 Copyright (C) 2016 Apple Inc. All Rights Reserved.

 See LICENSE.txt for this sample’s licensing information

 Abstract:

 An example demonstrating adding accessibility to an NSView subclass that behaves like a group by implementing the NSAccessibilityGroup protocol

  and using NSAccessibilityElement to represent each of the items the view draws.

 */

#import "AAPLTicTacToeBoardView.h"

#import "AAPLTicTacToeSquareAccessibilityElement.h"

@implementation AAPLTicTacToeBoardView

@synthesize accessibilityChildren = _accessibilityChildren;

- (NSRect)squareRectforRow:(NSUInteger)row column:(NSUInteger)column

{

    AAPLTicTacToeBoard *board = self.game.board;

    NSRect bounds = self.bounds;

    CGFloat height = bounds.size.height;

    CGFloat squareWidth = bounds.size.width / board.numColumns;

    CGFloat squareHeight = height / board.numRows;

    CGFloat inset = squareWidth / 5.0;

    NSRect squareRect = NSZeroRect;

    if ( row < board.numRows && column < board.numColumns )

    {

            squareRect = NSMakeRect(column * squareWidth + inset,

                                   height - (row + 1) * squareHeight + inset,

                                   squareWidth - 2 * inset,

                                   squareHeight - 2 * inset);

    }

    return squareRect;

}

#pragma mark - Mouse Event Handling

- (void)mouseUp:(NSEvent *)mouseEvent

{

    NSPoint localPoint = [self convertPoint:mouseEvent.locationInWindow fromView:nil];

    CGFloat row = floor((self.bounds.size.height - localPoint.y) / (self.bounds.size.height / 3.0));

    CGFloat column = floor(localPoint.x / (self.bounds.size.width / 3.0));

    [self.delegate playSquareAtRow:row column:column];

    [self setNeedsDisplay:YES];

}

#pragma mark - Drawing

- (void)drawRect:(NSRect)dirtyRect

{

    [super drawRect:dirtyRect];

    [self drawGrid];

    [self drawSquares];

    [self drawWinLine];

}

- (void)drawGrid

{

    NSRect bounds = self.bounds;

    CGFloat width = bounds.size.width;

    CGFloat height = bounds.size.height;

    [[NSColor blackColor] set];

    [NSBezierPath setDefaultLineWidth:1.0];

    [NSBezierPath strokeLineFromPoint:NSMakePoint(width / 3.0, 0.0) toPoint:NSMakePoint(width / 3.0, height)];

    [NSBezierPath strokeLineFromPoint:NSMakePoint(2.0 * width / 3.0, 0.0) toPoint:NSMakePoint(2.0 * width / 3.0, height)];

    [NSBezierPath strokeLineFromPoint:NSMakePoint(0.0, height / 3.0) toPoint:NSMakePoint(width, height/ 3.0)];

    [NSBezierPath strokeLineFromPoint:NSMakePoint(0.0, 2.0 * height / 3.0 ) toPoint:NSMakePoint(width, 2.0 * height / 3.0)];

}

- (void)drawSquares

{

    [NSBezierPath setDefaultLineWidth:3.0];

    AAPLTicTacToeGame *game = self.game;

    AAPLTicTacToeBoard *board = game.board;

    AAPLTicTacToeSquare *square;

    NSUInteger numRows = board.numRows;

    NSUInteger numColumns = board.numColumns;

    for ( NSUInteger row = 0; row < numRows; row++ )

    {

        for ( NSUInteger column = 0; column < numColumns; column++ )

        {

            square = [board squareAtRow:row column:column];

            if ( square.isX )

            {

                [self drawXAtRow:row column:column];

            }

            else if ( square.isO )

            {

                [self drawOAtRow:row column:column];

            }

        }

    }

}

- (void)drawXAtRow:(NSUInteger)row column:(NSUInteger)column

{

    NSRect squareRect = [self squareRectforRow:row column:column];

    NSPoint topLeft = NSMakePoint(NSMinX(squareRect), NSMaxY(squareRect));

    NSPoint topRight = NSMakePoint(NSMaxX(squareRect), NSMaxY(squareRect));

    NSPoint bottomLeft = NSMakePoint(NSMinX(squareRect), NSMinY(squareRect));

    NSPoint bottomRight = NSMakePoint(NSMaxX(squareRect), NSMinY(squareRect));

    [NSBezierPath strokeLineFromPoint:topLeft toPoint:bottomRight];

    [NSBezierPath strokeLineFromPoint:topRight toPoint:bottomLeft];

}

- (void)drawOAtRow:(NSUInteger)row column:(NSUInteger)column

{

    NSRect squareRect = [self squareRectforRow:row column:column];

    NSPoint center = NSMakePoint(NSMidX(squareRect), NSMidY(squareRect));

    NSBezierPath *circlePath = [[NSBezierPath alloc] init];

    [circlePath appendBezierPathWithArcWithCenter:center radius:squareRect.size.height / 2.0  startAngle:0 endAngle:360.0];

    [circlePath stroke];

}

- (void)drawWinLine

{

    AAPLTicTacToeGame *game = self.game;

    NSUInteger height = self.bounds.size.height;

    NSUInteger width = self.bounds.size.width;

    switch ( game.winType )

    {

        case AAPLTicTacToeGameWinTypeRow:

            [NSBezierPath setDefaultLineWidth:4];

            [[NSColor redColor] set];

            [NSBezierPath strokeLineFromPoint:NSMakePoint(0.0, height - (2 * game.winningRow + 1) * (height / 6.0))

                                      toPoint:NSMakePoint(width, height - (2 * game.winningRow + 1) * (height / 6.0))];

            break;

        case AAPLTicTacToeGameWinTypeColumn:

            [NSBezierPath setDefaultLineWidth:4];

            [[NSColor redColor] set];

            [NSBezierPath strokeLineFromPoint:NSMakePoint((2 * game.winningColumn + 1) * (width / 6.0), 0.0)

                                      toPoint:NSMakePoint((2 * game.winningColumn + 1) * (width / 6.0), height)];

            break;

        case AAPLTicTacToeGameWinTypeTopLeftDiagonal:

            [NSBezierPath setDefaultLineWidth:4];

            [[NSColor redColor] set];

            [NSBezierPath strokeLineFromPoint:NSMakePoint(0.0, height)

                                      toPoint:NSMakePoint(width, 0.0)];

            break;

        case AAPLTicTacToeGameWinTypeTopRightDiagonal:

            [NSBezierPath setDefaultLineWidth:4];

            [[NSColor redColor] set];

            [NSBezierPath strokeLineFromPoint:NSMakePoint(0.0, 0.0)

                                      toPoint:NSMakePoint(width, height)];

            break;

        default:

            break;

    }

}

#pragma mark - Accessibility

- (NSString *)accessibilityLabel

{

    return NSLocalizedString(@"tic tac toe board", nil);

}

// This view draws all of its elements (the tic tac toe squares) itself.

// NSAccessibilityElement is used to make these squares individually available to accessibility clients

// by returning an element for each square from -(NSArray *)accessibilityChildren

- (NSArray *)accessibilityChildren

{

    // if the children haven't been created yet

    if ( _accessibilityChildren == nil )

    {

        // make an array to hold them

        NSMutableArray *accessibilityChildren = [NSMutableArray new];

        AAPLTicTacToeBoard *board = self.game.board;

        AAPLTicTacToeSquareAccessibilityElement *squareAccessibilityElement;

        // for each square of the board

        for ( NSUInteger row = 0; row < board.numRows; row++ )

        {

            for ( NSUInteger column = 0; column < board.numColumns; column++ )

            {

                // create an accessibility element for the square

                squareAccessibilityElement = [[AAPLTicTacToeSquareAccessibilityElement alloc] initWithRow:row

                                                                                                   column:column

                                                                                                 delegate:self.delegate];

                // set the parent and frame

                squareAccessibilityElement.accessibilityParent = self;

                squareAccessibilityElement.accessibilityFrameInParentSpace = [self squareRectforRow:row column:column];

                // and add it to the array

                [accessibilityChildren addObject:squareAccessibilityElement];

            }

        }

        // hold onto the accessibility elements the entire time they are shown in the UI

        _accessibilityChildren = accessibilityChildren;

    }

    return _accessibilityChildren;

}

#pragma mark - Support IB_DESIGNABLE

// Executed when your view is being prepared for display in Interface Builder.

- (void)prepareForInterfaceBuilder

{

    // Add visual interest in Interface Builder by instantiating a game and playing two moves.

    self.game = [AAPLTicTacToeGame new];

    [self.game playSquareAtRow:0 column:0];

    [self.game playSquareAtRow:1 column:1];

}

@end