UIViewController+LayoutProtocol.m

#import "UIViewController+LayoutProtocol.h"
#import <objc/runtime.h>

@implementation UIViewController (LayoutProtocol)

- (instancetype)initWithLayoutInfo:(RNNLayoutInfo *)layoutInfo
                           creator:(id<RNNComponentViewCreator>)creator
                           options:(RNNNavigationOptions *)options
                    defaultOptions:(RNNNavigationOptions *)defaultOptions
                         presenter:(RNNBasePresenter *)presenter
                      eventEmitter:(RNNEventEmitter *)eventEmitter
              childViewControllers:(NSArray *)childViewControllers {
    self = [self init];
    self.options = options;
    self.defaultOptions = defaultOptions;
    self.layoutInfo = layoutInfo;
    self.creator = creator;
    self.eventEmitter = eventEmitter;
    self.presenter = presenter;
    [self loadChildren:childViewControllers];
    [self.presenter bindViewController:self];
    self.extendedLayoutIncludesOpaqueBars = YES;
    [self.presenter applyOptionsOnInit:self.resolveOptions];

    return self;
}

- (void)mergeOptions:(RNNNavigationOptions *)options {
    [self.options mergeOptions:options];
    [self.presenter mergeOptions:options resolvedOptions:self.resolveOptions];
    [self.parentViewController mergeChildOptions:options child:self];
}

- (void)mergeChildOptions:(RNNNavigationOptions *)options child:(UIViewController *)child {
    [self.presenter mergeOptions:options resolvedOptions:self.resolveOptions];
    [self.parentViewController mergeChildOptions:options child:child];
}

- (RNNNavigationOptions *)resolveOptions {
    return (RNNNavigationOptions *)[self.options.copy
        mergeOptions:self.getCurrentChild.resolveOptions];
}

- (RNNNavigationOptions *)resolveOptionsWithDefault {
    return [(RNNNavigationOptions *)[self.options.copy
        mergeOptions:self.getCurrentChild.resolveOptions] withDefault:self.defaultOptions];
}

- (UINavigationController *)stack {
    if ([self isKindOfClass:UINavigationController.class]) {
        return (UINavigationController *)self;
    } else {
        return self.navigationController;
    }
}

- (void)render {
    if (!self.waitForRender) {
        [self readyForPresentation];
    }

    [self.getCurrentChild setReactViewReadyCallback:^{
      [self.presenter renderComponents:self.resolveOptionsWithDefault
                               perform:^{
                                 [self readyForPresentation];
                               }];
    }];

    [self.getCurrentChild render];
}

- (void)loadChildren:(NSArray *)children {
    if (!self.isChildViewControllersLoaded &&
        [self respondsToSelector:@selector(setViewControllers:)]) {
        self.isChildViewControllersLoaded = YES;
        [self performSelector:@selector(setViewControllers:) withObject:children];
    }
}

- (void)readyForPresentation {
    if (self.reactViewReadyCallback) {
        self.reactViewReadyCallback();
        self.reactViewReadyCallback = nil;
    }

    [self.parentViewController readyForPresentation];
}

- (UIViewController *)getCurrentChild {
    for (UIViewController *childViewController in self.childViewControllers.reverseObjectEnumerator
             .allObjects) {
        if (childViewController.layoutInfo) {
            return childViewController;
        }
    }

    return nil;
}

- (void)destroy {
    [self destroyReactView];
    [self.presentedViewController destroy];

    for (UIViewController *child in self.childViewControllers) {
        [child destroy];
    }
}

- (void)destroyReactView {
}

- (void)prepareForTransition {
    [self.view setNeedsLayout];
    [self.view layoutIfNeeded];
    if (self.navigationController) {
        [self.navigationController.navigationBar setNeedsLayout];
    } else if ([self isKindOfClass:UINavigationController.class]) {
        [((UINavigationController *)self).navigationBar setNeedsLayout];
    }
}

- (UIViewController *)presentedComponentViewController {
    UIViewController *currentChild = self.getCurrentChild;
    return currentChild ? currentChild.presentedComponentViewController : self;
}

- (UIViewController *)topMostViewController {
    if (self.parentViewController) {
        return [self.parentViewController topMostViewController];
    } else
        return self;
}

- (UIViewController *)findViewController:(UIViewController *)child {
    if (self == child)
        return child;

    for (UIViewController *childController in self.childViewControllers) {
        UIViewController *fromChild = [childController findViewController:child];
        if (fromChild)
            return childController;
    }

    return nil;
}

- (CGFloat)getTopBarHeight {
    for (UIViewController *child in [self childViewControllers]) {
        CGFloat childTopBarHeight = [child getTopBarHeight];
        if (childTopBarHeight > 0)
            return childTopBarHeight;
    }

    return 0;
}

- (CGFloat)getBottomTabsHeight {
    for (UIViewController *child in [self childViewControllers]) {
        CGFloat childBottomTabsHeight = [child getBottomTabsHeight];
        if (childBottomTabsHeight > 0)
            return childBottomTabsHeight;
    }

    return 0;
}

- (void)screenPopped {
}

- (void)onChildWillAppear {
    [self.presenter applyOptions:self.resolveOptions];
    [self.parentViewController onChildWillAppear];
}

- (void)onChildAddToParent:(UIViewController *)child options:(RNNNavigationOptions *)options {
    [self.parentViewController onChildAddToParent:child options:options];
}

- (void)componentWillAppear {
    [self.presenter componentWillAppear];
    [self.parentViewController componentWillAppear];
}

- (void)componentDidAppear {
    [self.presenter componentDidAppear];
    [self.parentViewController componentDidAppear];
}

- (void)componentDidDisappear {
    [self.presenter componentDidDisappear];
    [self.parentViewController componentDidDisappear];
}

#pragma mark getters and setters to associated object

- (RNNReactView *)reactView {
    return objc_getAssociatedObject(self, @selector(reactView));
}

- (void)setReactView:(RNNReactView *)reactView {
    objc_setAssociatedObject(self, @selector(reactView), reactView,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (RNNNavigationOptions *)options {
    return objc_getAssociatedObject(self, @selector(options));
}

- (void)setOptions:(RNNNavigationOptions *)options {
    objc_setAssociatedObject(self, @selector(options), options, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (RNNNavigationOptions *)defaultOptions {
    return objc_getAssociatedObject(self, @selector(defaultOptions));
}

- (void)setDefaultOptions:(RNNNavigationOptions *)defaultOptions {
    objc_setAssociatedObject(self, @selector(defaultOptions), defaultOptions,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    self.presenter.defaultOptions = defaultOptions;
}

- (RNNLayoutInfo *)layoutInfo {
    return objc_getAssociatedObject(self, @selector(layoutInfo));
}

- (void)setLayoutInfo:(RNNLayoutInfo *)layoutInfo {
    objc_setAssociatedObject(self, @selector(layoutInfo), layoutInfo,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (RNNBasePresenter *)presenter {
    return objc_getAssociatedObject(self, @selector(presenter));
}

- (void)setPresenter:(RNNBasePresenter *)presenter {
    objc_setAssociatedObject(self, @selector(presenter), presenter,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (RNNEventEmitter *)eventEmitter {
    return objc_getAssociatedObject(self, @selector(eventEmitter));
}

- (void)setEventEmitter:(RNNEventEmitter *)eventEmitter {
    objc_setAssociatedObject(self, @selector(eventEmitter), eventEmitter,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (BOOL)isChildViewControllersLoaded {
    return [objc_getAssociatedObject(self, @selector(isChildViewControllersLoaded)) boolValue];
}

- (void)setIsChildViewControllersLoaded:(BOOL)isChildViewControllersLoaded {
    objc_setAssociatedObject(self, @selector(isChildViewControllersLoaded),
                             [NSNumber numberWithBool:isChildViewControllersLoaded],
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (id<RNNComponentViewCreator>)creator {
    return objc_getAssociatedObject(self, @selector(creator));
}

- (void)setCreator:(id<RNNComponentViewCreator>)creator {
    objc_setAssociatedObject(self, @selector(creator), creator, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (RNNReactViewReadyCompletionBlock)reactViewReadyCallback {
    return objc_getAssociatedObject(self, @selector(reactViewReadyCallback));
}

- (void)setReactViewReadyCallback:(RNNReactViewReadyCompletionBlock)reactViewReadyCallback {
    objc_setAssociatedObject(self, @selector(reactViewReadyCallback), reactViewReadyCallback,
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

- (BOOL)waitForRender {
    return [objc_getAssociatedObject(self.parentViewController ?: self, @selector(waitForRender))
        boolValue];
}

- (void)setWaitForRender:(BOOL)waitForRender {
    objc_setAssociatedObject(self, @selector(waitForRender),
                             [NSNumber numberWithBool:waitForRender],
                             OBJC_ASSOCIATION_RETAIN_NONATOMIC);
    self.getCurrentChild.waitForRender = waitForRender;
}

@end