/*

    Copyright (C) 2015 Apple Inc. All Rights Reserved.

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    This is the "SlideCarrierView" class implementation.

*/

#import "AAPLSlideCarrierView.h"

#import "AAPLSlideBorderView.h"

#import "AAPLSlideImageView.h"

#import <QuartzCore/QuartzCore.h>

@implementation AAPLSlideCarrierView

#pragma mark Animation

// Override the default @"frameOrigin" animation for SlideCarrierViews, to use an "EaseInEaseOut" timing curve.

+ (id)defaultAnimationForKey:(NSString *)key {

    static CABasicAnimation *basicAnimation = nil;

    if ([key isEqual:@"frameOrigin"]) {

        if (basicAnimation == nil) {

            basicAnimation = [[CABasicAnimation alloc] init];

            [basicAnimation setTimingFunction:[CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut]];

        }

        return basicAnimation;

    } else {

        return [super defaultAnimationForKey:key];

    }

}

#pragma mark Initializing

- (nonnull instancetype)initWithFrame:(NSRect)frameRect {

    self = [super initWithFrame:frameRect];

    if (self) {

        highlightState = NSCollectionViewItemHighlightNone;

    }

    return self;

}

#pragma mark Property Accessors

- (NSCollectionViewItemHighlightState)highlightState {

    return highlightState;

}

- (void)setHighlightState:(NSCollectionViewItemHighlightState)newHighlightState {

    if (highlightState != newHighlightState) {

        highlightState = newHighlightState;

        // Cause our -updateLayer method to be invoked, so we can update our appearance to reflect the new state.

        [self setNeedsDisplay:YES];

    }

}

- (BOOL)isSelected {

    return selected;

}

- (void)setSelected:(BOOL)flag {

    if (selected != flag) {

        selected = flag;

        // Cause our -updateLayer method to be invoked, so we can update our appearance to reflect the new state.

        [self setNeedsDisplay:YES];

    }

}

#pragma mark Visual State

// A AAPLSlideCarrierView wants to receive -updateLayer so it can set its backing layer's contents property, instead of being sent -drawRect: to draw its content procedurally.

- (BOOL)wantsUpdateLayer {

    return YES;

}

// Returns the slide's AAPLSlideBorderView (if it currently has one).

- (AAPLSlideBorderView *)borderView {

    for (NSView *subview in self.subviews) {

        if ([subview isKindOfClass:[AAPLSlideBorderView class]]) {

            return (AAPLSlideBorderView *)subview;

        }

    }

    return nil;

}

// Invoked from our -updateLayer override.  Adds a AAPLSlideBorderView subview with appropriate properties (or removes an existing AAPLSlideBorderView), as appropriate to visually indicate the slide's "highlightState" and whether the slide is "selected".

- (void)updateBorderView {

    NSColor *borderColor = nil;

    if (highlightState == NSCollectionViewItemHighlightForSelection) {

        // Item is a candidate to become selected: Show an orange border around it.

        borderColor = [NSColor orangeColor];

    } else if (highlightState == NSCollectionViewItemHighlightAsDropTarget) {

        // Item is a candidate to receive dropped items: Show a red border around it.

        borderColor = [NSColor redColor];

    } else if (selected && highlightState != NSCollectionViewItemHighlightForDeselection) {

        // Item is selected, and is not indicated for proposed deselection: Show an Aqua border around it.

        borderColor = [NSColor colorWithCalibratedRed:0.0 green:0.5 blue:1.0 alpha:1.0]; // Aqua

    } else {

        // Item is either not selected, or is selected but not highlighted for deselection: Sbhow no border around it.

        borderColor = nil;

    }

    // Add/update or remove a AAPLSlideBorderView subview, according to whether borderColor != nil.

    AAPLSlideBorderView *borderView = self.borderView;

    if (borderColor) {

        if (borderView == nil) {

            NSRect bounds = self.bounds;

            NSRect shapeBox = NSInsetRect(bounds, (SLIDE_SHADOW_MARGIN - 0.5 * SLIDE_BORDER_WIDTH), (SLIDE_SHADOW_MARGIN - 0.5 * SLIDE_BORDER_WIDTH));

            borderView = [[AAPLSlideBorderView alloc] initWithFrame:shapeBox];

            [self addSubview:borderView];

        }

        borderView.borderColor = borderColor;

    } else {

        [borderView removeFromSuperview];

    }

}

- (void)updateLayer {

    // Provide the SlideCarrierView's backing layer's contents directly, instead of via -drawRect:.

    self.layer.contents = [NSImage imageNamed:@"SlideCarrier"];

    // Use this as an opportunity to update our AAPLSlideBorderView.

    [self updateBorderView];

}

// Used by our -hitTest: method, below.  Returns the slide's rounded-rectangle hit-testing shape, expressed as an NSBezierPath.

- (NSBezierPath *)slideShape {

    NSRect bounds = self.bounds;

    NSRect shapeBox = NSInsetRect(bounds, SLIDE_SHADOW_MARGIN, SLIDE_SHADOW_MARGIN);

    return [NSBezierPath bezierPathWithRoundedRect:shapeBox xRadius:SLIDE_CORNER_RADIUS yRadius:SLIDE_CORNER_RADIUS];

}

- (NSView *)hitTest:(NSPoint)aPoint {

    // Hit-test against the slide's rounded-rect shape.

    NSPoint pointInSelf = [self convertPoint:aPoint fromView:self.superview];

    NSRect bounds = self.bounds;

    if (!NSPointInRect(pointInSelf, bounds)) {

        return NO;

    } else if (![self.slideShape containsPoint:pointInSelf]) {

        return NO;

    } else {

        return [super hitTest:aPoint];

    }

}

@end