/*

File: DCDiceView-Accessibility.m

Abstract: Accessibility implementation for dice view

Version: 1.0

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*/ 

#import "DCDiceView.h"

#import "DCDie.h"

@implementation DCDiceView (Accessibility)

/* Override accessibilityIsIgnored to return NO.

    See what you inherit for free from NSView */

-(BOOL)accessibilityIsIgnored {

    return NO;

}

/* Override the role attribute.  Note that the role description automatically updates.

*/

- (id)accessibilityAttributeValue:(NSString *)attribute {

    id attributeValue = nil;

    if ([attribute isEqualToString: NSAccessibilityRoleAttribute]) {

        attributeValue = NSAccessibilityGroupRole;

    }   

    /* For the children attribute.  If we are cleared, then we have zero children, return an empty array.

        If we are showing dice, return the unignored children of the dice.

    */

    else if ([attribute isEqualToString: NSAccessibilityChildrenAttribute]) {

        if (isCleared) attributeValue = NSAccessibilityUnignoredChildren([NSArray array]);

        else attributeValue = NSAccessibilityUnignoredChildren(dice);

    } 

    else {

        attributeValue = [super accessibilityAttributeValue:attribute];

    }

    return attributeValue;

}

/* If this method is sent, it has been determined that the point is within our bounds.  So we hit test to see if the point hits any of our subelements.  If so, we send it the same message.  If not, we return ourself.  Note that the point is in screen coordinates.  We need to translate from screen to base (window) coordinates, and then from the window to local view coordinates.

    Also note that we pass the original point to our child.  Since we implement the same API in every object, the point passed to -accesibilityHitPoint: is always expected to be in screen coordinates.

*/

- (id)accessibilityHitTest:(NSPoint)point {

    id hitTestResult = self;

    if (!isCleared) {

        NSPoint windowPoint = [[self window] convertScreenToBase:point];

        NSPoint localPoint = [self convertPoint:windowPoint fromView: nil];

        NSEnumerator *enumerator = [dice objectEnumerator];

        DCDie *die = nil;

        DCDie *foundDie = nil;

        while (!foundDie && (die = [enumerator nextObject])) {

            if ([die containsPoint: localPoint]) {

                foundDie = die;

            }

        }

        if (foundDie) hitTestResult = [foundDie accessibilityHitTest:point];

    }

    return hitTestResult;

}

/* If this method has been called, it has already been determined that this object, or some subelement of this object, has the keyboard focus.  In this case we find the die that has the focus and pass the message along, returning the result we provide back.

*/

- (id)accessibilityFocusedUIElement {

    if (shouldDisplayFocus && [[self window] firstResponder] == self && firstResponderIndex != -1) {

        return [[dice objectAtIndex: firstResponderIndex] accessibilityFocusedUIElement];

    }

    else return self;

}

@end