/*

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

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    The `AAPLMovieTimeline` and `AAPLMovieTimelineDelegate` protocols provide the infrastructure for drawing video track images in a timeline like view and track cursor movements and selections.

 */

#import "AAPLMovieTimeline.h"

#import "AAPLTimeRangeView.h"

#import <QuartzCore/QuartzCore.h>

@interface AAPLMovieTimeline()

@property NSUInteger imagesAdded;

@property CALayer *markerLayer;

@property NSTrackingArea *trackingArea;

@property CALayer *startPointMarker;

@property NSPoint startingPoint;

@property NSPoint endingPoint;

@property NSUInteger numberOfMarkers;

@property AAPLTimeRangeView *timeRangeView;

@property NSTextField *timeLabel;

@end

@implementation AAPLMovieTimeline

#pragma mark - initializers

- (instancetype)initWithCoder:(nonnull NSCoder *)coder {

    if (self = [super initWithCoder:coder]) {

        // Setup a layer with a black background color

        self.wantsLayer = YES;

        self.layer = [CALayer layer];

        self.layer.backgroundColor = [NSColor blackColor].CGColor;

        self.timeLabel = [[NSTextField alloc] init];

        [self setupMarkerLayer];

        //Add a tracking area to track the cursor in this view

        self.trackingArea = [[NSTrackingArea alloc] initWithRect:NSMakeRect(-1.0, 0.0, self.frame.size.width, self.frame.size.height) options:(NSTrackingMouseMoved | NSTrackingActiveAlways) owner:self userInfo:nil];

        [self addTrackingArea:self.trackingArea];

    }

    return self;

}

- (CGFloat)imageViewWidth {

    return (self.frame.size.height * 16) / 9;

}

#pragma mark - Subview/Layer Management

- (void)layout {

    // Remove the tracking area and re-add it when we layout in case the frame has changed size.

    if (self.trackingArea != nil) {

        [self removeTrackingArea:self.trackingArea];

        self.trackingArea = [[NSTrackingArea alloc] initWithRect:NSMakeRect(-1.0, 0.0, self.frame.size.width, self.frame.size.height) options:(NSTrackingMouseMoved | NSTrackingActiveAlways) owner:self userInfo:nil];

        [self addTrackingArea:self.trackingArea];

    }

    [super layout];

}

- (void)setupMarkerLayer {

    // Add the markerlayer and the timelabel for the timeline.

    self.markerLayer = [CALayer layer];

    self.markerLayer.frame = CGRectMake(0.0f, 0.0f, 5.0, self.frame.size.height);

    self.markerLayer.backgroundColor = [NSColor redColor].CGColor;

    [self.layer addSublayer:self.markerLayer];

    self.timeLabel.frame = NSMakeRect(self.frame.origin.x, self.frame.origin.y, 50.0f, 25.0f);

    self.timeLabel.backgroundColor = [NSColor clearColor];

    self.timeLabel.textColor = [NSColor whiteColor];

    self.timeLabel.drawsBackground = NO;

    self.timeLabel.editable = NO;

    self.timeLabel.bezeled = NO;

    [self addSubview:self.timeLabel];

}

- (void)updateTimeLabel:(NSString *)newLabel {

    self.timeLabel.stringValue = newLabel;

}

- (void)addImageView:(NSImage *)image {

    CGFloat nextX = self.imagesAdded * self.imageViewWidth;

    NSImageView *nextView = [[NSImageView alloc] initWithFrame:NSMakeRect(nextX, 0.0, self.imageViewWidth, self.frame.size.height)];

    nextView.image = image;

    [self addSubview:nextView];

    [self setNeedsDisplayInRect:self.frame];

    self.imagesAdded++;

    // Remove the marker layer and time label then re add them to draw above the images.

    [self.markerLayer removeFromSuperlayer];

    [self.timeLabel removeFromSuperview];

    [self addSubview:self.timeLabel];

    [self.layer addSublayer:self.markerLayer];

}

- (void)removeAllPositionalSubviews {

    [self.subviews enumerateObjectsUsingBlock:^(__kindof NSView * __nonnull subView, NSUInteger idx, BOOL * __nonnull stop) {

        [subView removeFromSuperview];

    }];

    self.imagesAdded = 0;

}

- (NSUInteger)countOfImagesRequiredToFillView {

    return floor(self.frame.size.width / self.imageViewWidth);

}

#pragma mark - Cursor Movement methods

- (void)moveMarkerLayerAndtimeLabelWithMouse:(NSEvent *)theEvent {

    NSPoint windowLocation = theEvent.locationInWindow;

    NSPoint newPoint = [self convertPoint:windowLocation fromView:nil];

    [CATransaction begin];

    [CATransaction setDisableActions:YES];

    self.markerLayer.frame = CGRectMake(newPoint.x, 0.0f, 5.0f, self.frame.size.height);

    self.timeLabel.frame = NSMakeRect(newPoint.x + 5.0f, 0.0f, 50.0f, 25.0f);

    [CATransaction commit];

    [self.delegate movieTimeline:self didUpdateCursorToPoint:newPoint];

}

- (void)mouseDown:(nonnull NSEvent *)theEvent {

    [self.timeRangeView removeFromSuperview];

    self.startingPoint = [self convertPoint:theEvent.locationInWindow toView:nil];

}

- (void)mouseMoved:(nonnull NSEvent *)theEvent {

    [self moveMarkerLayerAndtimeLabelWithMouse:theEvent];

}

- (void)mouseDragged:(nonnull NSEvent *)theEvent {

    [self moveMarkerLayerAndtimeLabelWithMouse:theEvent];

}

- (void)mouseUp:(nonnull NSEvent *)theEvent {

    self.endingPoint = [self convertPoint:theEvent.locationInWindow fromView:nil];

    if (self.startingPoint.x == self.endingPoint.x) {

        [self.timeRangeView removeFromSuperview];

        self.startPointMarker.frame = CGRectMake(self.endingPoint.x, 0.0f, 5.0f, self.frame.size.height);

        self.startPointMarker.backgroundColor = [NSColor yellowColor].CGColor;

        [self.delegate didSelectTimelinePoint:self.endingPoint];

    } else {

        [self.startPointMarker removeFromSuperlayer];

        self.timeRangeView = [[AAPLTimeRangeView alloc] initWithFrame:NSMakeRect(self.startingPoint.x, 0.0, self.endingPoint.x - self.startingPoint.x, self.frame.size.height)];

        [self addSubview:self.timeRangeView];

        [self.delegate didSelectTimelineRangeFromPoint:self.startingPoint toPoint:self.endingPoint];

        self.endingPoint = NSZeroPoint;

    }

}

@end