/*

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

See LICENSE.txt for this sample’s licensing information

Abstract:

Controller that manages the full tile view of the atomic information, creating the reflection, and the flipping of the tile.

*/

#import "AtomicElementViewController.h"

#import "AtomicElementView.h"

#import "AtomicElementFlippedView.h"

#import "AtomicElement.h"

#define kFlipTransitionDuration 0.75

#define reflectionFraction 0.35

#define reflectionOpacity 0.5

@interface AtomicElementViewController ()

@property (assign) BOOL frontViewIsVisible;

@property (nonatomic, strong) AtomicElementView *atomicElementView;

@property (nonatomic, strong) UIImageView *reflectionView;

@property (nonatomic, strong) AtomicElementFlippedView *atomicElementFlippedView;

@property (nonatomic, strong) UIButton *flipIndicatorButton;

@end

#pragma mark -

@implementation AtomicElementViewController

- (void)viewDidLoad {

    [super viewDidLoad];

    self.frontViewIsVisible = YES;

    CGSize preferredAtomicElementViewSize = [AtomicElementView preferredViewSize];

    CGRect viewRect = CGRectMake((CGRectGetWidth(self.view.bounds) - preferredAtomicElementViewSize.width)/2,

                                 (CGRectGetHeight(self.view.bounds) - preferredAtomicElementViewSize.height)/2 - 40,

                                 preferredAtomicElementViewSize.width,

                                 preferredAtomicElementViewSize.height);

    // create the atomic element view

    AtomicElementView *localAtomicElementView = [[AtomicElementView alloc] initWithFrame:viewRect];

    self.atomicElementView = localAtomicElementView;

    // add the atomic element view to the view controller's view

    self.atomicElementView.element = self.element;  

    [self.view addSubview:self.atomicElementView];

    self.atomicElementView.viewController = self;

    // create the atomic element flipped view

    AtomicElementFlippedView *localAtomicElementFlippedView = [[AtomicElementFlippedView alloc] initWithFrame:viewRect];

    self.atomicElementFlippedView = localAtomicElementFlippedView;

    self.atomicElementFlippedView.element = self.element;   

    self.atomicElementFlippedView.viewController = self;

    // create the reflection view

    CGRect reflectionRect = viewRect;

    // the reflection is a fraction of the size of the view being reflected

    reflectionRect.size.height = CGRectGetHeight(reflectionRect) * reflectionFraction;

    // and is offset to be at the bottom of the view being reflected

    reflectionRect = CGRectOffset(reflectionRect, 0, CGRectGetHeight(viewRect));

    UIImageView *localReflectionImageView = [[UIImageView alloc] initWithFrame:reflectionRect];

    self.reflectionView = localReflectionImageView;

    // determine the size of the reflection to create

    NSUInteger reflectionHeight = CGRectGetHeight(self.atomicElementView.bounds) * reflectionFraction;

    // create the reflection image, assign it to the UIImageView and add the image view to the view controller's view

    self.reflectionView.image = [self.atomicElementView reflectedImageRepresentationWithHeight:reflectionHeight];

    self.reflectionView.alpha = reflectionOpacity;

    [self.view addSubview:self.reflectionView];

    // setup our flip indicator button (placed as a nav bar item to the right)

    UIButton *localFlipIndicator = [[UIButton alloc] initWithFrame:CGRectMake(0.0, 0.0, 30.0, 30.0)];

    self.flipIndicatorButton = localFlipIndicator;

    // front view is always visible at first

    [self.flipIndicatorButton setBackgroundImage:[UIImage imageNamed:@"flipper_list_blue.png"] forState:UIControlStateNormal];

    UIBarButtonItem *flipButtonBarItem;

    flipButtonBarItem = [[UIBarButtonItem alloc] initWithCustomView:self.flipIndicatorButton];

    [self.flipIndicatorButton addTarget:self

                                 action:@selector(flipCurrentView)

                       forControlEvents:(UIControlEventTouchDown)];

    [self.navigationItem setRightBarButtonItem:flipButtonBarItem animated:YES];

}

- (void)flipCurrentView {

    NSUInteger reflectionHeight;

    UIImage *reflectedImage;

    // disable user interaction during the flip animation

    self.view.userInteractionEnabled = NO;

    self.flipIndicatorButton.userInteractionEnabled = NO;

    // setup the animation group

    [UIView beginAnimations:nil context:nil];

    [UIView setAnimationDuration:kFlipTransitionDuration];

    [UIView setAnimationDelegate:self];

    [UIView setAnimationDidStopSelector:@selector(myTransitionDidStop:finished:context:)];

    // swap the views and transition

    if (self.frontViewIsVisible == YES) {

        [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.view cache:YES];

        [self.atomicElementView removeFromSuperview];

        [self.view addSubview:self.atomicElementFlippedView];

        // update the reflection image for the new view

        reflectionHeight = CGRectGetHeight(self.atomicElementFlippedView.bounds) * reflectionFraction;

        reflectedImage = [self.atomicElementFlippedView reflectedImageRepresentationWithHeight:reflectionHeight];

        _reflectionView.image = reflectedImage;

    } else {

        [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.view cache:YES];

        [self.atomicElementFlippedView removeFromSuperview];

        [self.view addSubview:self.atomicElementView];

        // update the reflection image for the new view

        reflectionHeight = CGRectGetHeight(self.atomicElementView.bounds) * reflectionFraction;

        reflectedImage = [self.atomicElementView reflectedImageRepresentationWithHeight:reflectionHeight];

        self.reflectionView.image = reflectedImage;

    }

    [UIView commitAnimations];

    // swap the nav bar button views

    [UIView beginAnimations:nil context:nil];

    [UIView setAnimationDuration:kFlipTransitionDuration];

    [UIView setAnimationDelegate:self];

    [UIView setAnimationDidStopSelector:@selector(myTransitionDidStop:finished:context:)];

    if (self.frontViewIsVisible == YES) {

        [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromRight forView:self.flipIndicatorButton cache:YES];

        [self.flipIndicatorButton setBackgroundImage:self.element.flipperImageForAtomicElementNavigationItem forState:UIControlStateNormal];

    }

    else {

        [UIView setAnimationTransition:UIViewAnimationTransitionFlipFromLeft forView:self.flipIndicatorButton cache:YES];

        [self.flipIndicatorButton setBackgroundImage:[UIImage imageNamed:@"flipper_list_blue.png"] forState:UIControlStateNormal];

    }

    [UIView commitAnimations];

    // invert the front view state

    self.frontViewIsVisible =! self.frontViewIsVisible;

}

- (void)myTransitionDidStop:(NSString *)animationID finished:(NSNumber *)finished context:(void *)context {

    // re-enable user interaction when the flip animation is completed

    self.view.userInteractionEnabled = YES;

    self.flipIndicatorButton.userInteractionEnabled = YES;

}

@end