#import <XCTest/XCTest.h>

#import "RNCCollapsiblePagerViewComponentView.h"
#import "RNCPagerViewComponentView.h"
#import <react/renderer/components/pagerview/Props.h>

using namespace facebook::react;

@interface RNCCollapsiblePagerViewComponentView (ScrollEdgeTesting)
- (void)updateTopScrollEdgeForScrollView:(UIScrollView *)scrollView;
- (void)updateScrollEdgeContentMasks;
@end

@interface RNCCollapsiblePagerHitTestTests : XCTestCase
@property (nonatomic, strong) UIView *root;
@property (nonatomic, strong) UIButton *toolbar;
@property (nonatomic, strong) RNCCollapsiblePagerViewComponentView *pager;
@property (nonatomic, strong) UIButton *sticky;
@end

@implementation RNCCollapsiblePagerHitTestTests

- (void)setPointerEvents:(PointerEventsMode)mode
{
  auto props = std::make_shared<RNCCollapsiblePagerViewProps>();
  props->nativeSmoothHeaderScrollEnabled = true;
  props->pointerEvents = mode;
  [self.pager updateProps:props oldProps:nullptr];
}

- (void)setUp
{
  [super setUp];
  self.root = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 600)];
  self.toolbar = [[UIButton alloc] initWithFrame:CGRectMake(0, 36, 320, 64)];
  [self.root addSubview:self.toolbar];
  self.pager = [[RNCCollapsiblePagerViewComponentView alloc] init];
  [self setPointerEvents:PointerEventsMode::Auto];
  self.pager.frame = CGRectMake(0, 100, 320, 500);
  [self.root addSubview:self.pager];

  // Model smooth mode's header reparenting and its collapsed, clipped content.
  UIView *scroll = [[UIView alloc] initWithFrame:self.pager.bounds];
  [self.pager addSubview:scroll];
  UIView *header = [self.pager valueForKey:@"sharedHeaderHostView"];
  for (UIView *child in header.subviews.copy) [child removeFromSuperview];
  [scroll addSubview:header];
  header.frame = CGRectMake(0, -64, 320, 108);
  [header addSubview:[[UIButton alloc] initWithFrame:CGRectMake(0, 0, 320, 64)]];
  self.sticky = [[UIButton alloc] initWithFrame:CGRectMake(0, 140, 320, 44)];
  [header addSubview:self.sticky];
}

- (void)testCollapsedHeaderDoesNotInterceptSiblingToolbar
{
  XCTAssertEqual([self.root hitTest:CGPointMake(20, 80) withEvent:nil], self.toolbar);
}

- (void)testPinnedChildOutsideHeaderHostStillReceivesViewportTouches
{
  XCTAssertEqual([self.pager hitTest:CGPointMake(20, 90) withEvent:nil], self.sticky);
  [self setPointerEvents:PointerEventsMode::BoxNone];
  XCTAssertEqual([self.pager hitTest:CGPointMake(20, 90) withEvent:nil], self.sticky);
}

- (void)testFabricPointerEventsAreNotBypassed
{
  [self setPointerEvents:PointerEventsMode::None];
  XCTAssertNil([self.pager hitTest:CGPointMake(20, 90) withEvent:nil]);
  [self setPointerEvents:PointerEventsMode::BoxOnly];
  XCTAssertEqual([self.pager hitTest:CGPointMake(20, 90) withEvent:nil], self.pager);
}

- (void)testNoninteractivePagerDoesNotForwardHeaderTouches
{
  self.pager.hidden = YES;
  XCTAssertNil([self.pager hitTest:CGPointMake(20, 90) withEvent:nil]);
  self.pager.hidden = NO;
  self.pager.userInteractionEnabled = NO;
  XCTAssertNil([self.pager hitTest:CGPointMake(20, 90) withEvent:nil]);
  self.pager.userInteractionEnabled = YES;
  self.pager.alpha = 0.005;
  XCTAssertNil([self.pager hitTest:CGPointMake(20, 90) withEvent:nil]);
}

- (void)testExternalOverlayWithoutOuterPagerOwnsItsEdgeAndRegisteredOuterStillGates
{
  if (@available(iOS 26.0, *)) {
    UIWindow *window = [[UIWindow alloc] initWithFrame:self.root.bounds];
    [window addSubview:self.root];
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:self.pager.bounds];
    [self.pager addSubview:scrollView];
    UIScrollEdgeEffectStyle *originalStyle = scrollView.topEdgeEffect.style;
    [self.pager setValue:@YES forKey:@"topScrollEdgeEnabled"];
    [self.pager setValue:@(static_cast<NSInteger>(RNCCollapsiblePagerViewTopScrollEdgeEffect::Hard))
                 forKey:@"topScrollEdgeEffect"];
    [self.pager setValue:@123 forKey:@"externalTopOverlayTag"];
    [self.pager setValue:@64 forKey:@"externalTopOverlayHeight"];
    UIView *container = [self.pager valueForKey:@"containerView"];
    container.frame = self.pager.bounds;
    UIView *overlayHost = [self.pager valueForKey:@"topOverlayHostView"];
    overlayHost.frame = CGRectMake(0, 0, 320, 64);
    overlayHost.hidden = NO;
    self.pager.backgroundColor = UIColor.redColor;
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertEqual([self.pager valueForKey:@"topEdgeScrollView"], scrollView);
    UIScrollEdgeElementContainerInteraction *interaction =
      [self.pager valueForKey:@"topEdgeInteraction"];
    XCTAssertEqual(interaction.scrollView, scrollView);
    UIView *host = [self.pager valueForKey:@"topEdgeInteractionHost"];
    XCTAssertTrue([host.interactions containsObject:interaction]);
    XCTAssertEqual(scrollView.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);
    CALayer *cover = [self.pager valueForKey:@"topEdgeSeparatorCover"];
    XCTAssertEqual(cover.superlayer, container.layer);
    XCTAssertEqualWithAccuracy(CGRectGetMaxY(cover.frame), 64, 0.001);
    XCTAssertEqualWithAccuracy(CGRectGetHeight(cover.frame), 1.0 / window.screen.scale, 0.001);
    XCTAssertTrue(CGColorEqualToColor(cover.backgroundColor, UIColor.redColor.CGColor));
    UIEdgeInsets inset = scrollView.contentInset;
    CGPoint offset = scrollView.contentOffset;
    [self.pager setValue:@(static_cast<NSInteger>(RNCCollapsiblePagerViewTopScrollEdgeEffect::Soft))
                 forKey:@"topScrollEdgeEffect"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertEqual(scrollView.topEdgeEffect.style, UIScrollEdgeEffectStyle.softStyle);
    XCTAssertNil([self.pager valueForKey:@"topEdgeSeparatorCover"]);
    XCTAssertNil(cover.superlayer);
    XCTAssertEqual([self.pager valueForKey:@"topEdgeInteraction"], interaction);
    XCTAssertTrue(UIEdgeInsetsEqualToEdgeInsets(scrollView.contentInset, inset));
    XCTAssertTrue(CGPointEqualToPoint(scrollView.contentOffset, offset));

    RNCPagerViewComponentView *outer = [RNCPagerViewComponentView new];
    [self.pager setValue:outer forKey:@"externalOuterPager"];
    [self.pager setValue:@NO forKey:@"externalOuterPageActive"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertNil([self.pager valueForKey:@"topEdgeInteraction"]);
    [self.pager setValue:@YES forKey:@"externalOuterPageActive"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertNotNil([self.pager valueForKey:@"topEdgeInteraction"]);
    [self.pager setValue:@YES forKey:@"externalOuterTransitioning"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertNil([self.pager valueForKey:@"topEdgeInteraction"]);

    [self.pager setValue:nil forKey:@"externalOuterPager"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertNotNil([self.pager valueForKey:@"topEdgeInteraction"]);
    [self.pager removeFromSuperview];
    XCTAssertNil([self.pager valueForKey:@"topEdgeInteraction"]);
    XCTAssertNil([self.pager valueForKey:@"topEdgeScrollView"]);
    XCTAssertEqual(scrollView.topEdgeEffect.style, originalStyle);
    [self.root removeFromSuperview];
  } else {
    XCTSkip(@"Scroll-edge interactions require iOS 26 or newer");
  }
}

- (void)testPinnedHardEdgeHidesOnlyTopSeparatorCoverUntilUnpinned
{
  if (@available(iOS 26.0, *)) {
    UIWindow *window = [[UIWindow alloc] initWithFrame:self.root.bounds];
    [window addSubview:self.root];
    [self addTeardownBlock:^{ window.hidden = YES; }];
    window.hidden = NO;
    UIScrollView *scrollView = [[UIScrollView alloc] initWithFrame:self.pager.bounds];
    [self.pager addSubview:scrollView];
    [self.pager setValue:@YES forKey:@"topScrollEdgeEnabled"];
    [self.pager setValue:@(static_cast<NSInteger>(RNCCollapsiblePagerViewTopScrollEdgeEffect::Hard))
                 forKey:@"topScrollEdgeEffect"];
    [self.pager setValue:@123 forKey:@"externalTopOverlayTag"];
    [self.pager setValue:@64 forKey:@"externalTopOverlayHeight"];
    [self.pager setValue:self.sticky forKey:@"stickyHeaderView"];
    UIView *container = [self.pager valueForKey:@"containerView"];
    container.frame = self.pager.bounds;
    UIView *overlayHost = [self.pager valueForKey:@"topOverlayHostView"];
    overlayHost.frame = CGRectMake(0, 0, 320, 64);
    overlayHost.hidden = NO;
    UIView *pinnedHost = [self.pager valueForKey:@"pinnedStickyHostView"];
    pinnedHost.frame = CGRectMake(0, 64, 320, 44);
    pinnedHost.hidden = NO;
    [scrollView addSubview:pinnedHost];

    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    UIScrollEdgeElementContainerInteraction *topInteraction =
      [self.pager valueForKey:@"topEdgeInteraction"];
    CALayer *topCover = [self.pager valueForKey:@"topEdgeSeparatorCover"];
    XCTAssertNotNil(topInteraction);
    XCTAssertNotNil(topCover);
    XCTAssertFalse(topCover.hidden);
    XCTAssertEqual(scrollView.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);

    [self.pager setValue:@YES forKey:@"stickyHeaderIsPinned"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    UIScrollEdgeElementContainerInteraction *stickyInteraction =
      [self.pager valueForKey:@"stickyEdgeInteraction"];
    CALayer *stickyCover = [self.pager valueForKey:@"stickyEdgeSeparatorCover"];
    XCTAssertEqual([self.pager valueForKey:@"topEdgeInteraction"], topInteraction);
    XCTAssertEqual(topInteraction.scrollView, scrollView);
    XCTAssertEqual(stickyInteraction.scrollView, scrollView);
    XCTAssertEqual([self.pager valueForKey:@"topEdgeSeparatorCover"], topCover);
    XCTAssertTrue(topCover.hidden);
    XCTAssertNotNil(stickyCover);
    XCTAssertFalse(stickyCover.hidden);
    XCTAssertEqual(scrollView.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);

    [self.pager setValue:@NO forKey:@"stickyHeaderIsPinned"];
    [self.pager updateTopScrollEdgeForScrollView:scrollView];
    XCTAssertEqual([self.pager valueForKey:@"topEdgeInteraction"], topInteraction);
    XCTAssertEqual([self.pager valueForKey:@"topEdgeSeparatorCover"], topCover);
    XCTAssertFalse(topCover.hidden);
    XCTAssertEqual(scrollView.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);
    [self.root removeFromSuperview];
  } else {
    XCTSkip(@"Scroll-edge interactions require iOS 26 or newer");
  }
}

- (void)testIOS27LocalHardThemeBackgroundTracksMaskedHeaderGeometry
{
  if (@available(iOS 27.0, *)) {
    UIWindowScene *scene = nil;
    for (UIScene *connectedScene in UIApplication.sharedApplication.connectedScenes) {
      if ([connectedScene isKindOfClass:UIWindowScene.class]) {
        scene = (UIWindowScene *)connectedScene;
        break;
      }
    }
    XCTAssertNotNil(scene);
    UIWindow *window = [[UIWindow alloc] initWithWindowScene:scene];
    window.frame = self.root.bounds;
    [window addSubview:self.root];
    window.hidden = NO;
    [self addTeardownBlock:^{ window.hidden = YES; }];
    [self.pager layoutIfNeeded];
    self.pager.backgroundColor = [UIColor colorWithWhite:0.2 alpha:1];
    UIView *container = [self.pager valueForKey:@"containerView"];
    container.frame = self.pager.bounds;
    UIScrollView *scroll = [[UIScrollView alloc] initWithFrame:container.bounds];
    scroll.contentInsetAdjustmentBehavior = UIScrollViewContentInsetAdjustmentNever;
    scroll.alwaysBounceVertical = YES;
    scroll.contentSize = CGSizeMake(320, 1200);
    scroll.contentInset = UIEdgeInsetsMake(50 + 100 + 20, 0, 0, 0);
    [container insertSubview:scroll atIndex:0];
    UIView *sharedHost = [self.pager valueForKey:@"sharedHeaderHostView"];
    for (UIView *child in sharedHost.subviews.copy) [child removeFromSuperview];
    [scroll addSubview:sharedHost];
    sharedHost.frame = CGRectMake(0, -120, 320, 120);
    UIView *header = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 320, 100)];
    [sharedHost addSubview:header];
    [self.pager setValue:header forKey:@"headerView"];
    UIView *overlayHost = [self.pager valueForKey:@"topOverlayHostView"];
    overlayHost.frame = CGRectMake(0, 0, 320, 50);
    overlayHost.hidden = NO;
    UIView *overlay = [[UIView alloc] initWithFrame:overlayHost.bounds];
    [overlayHost addSubview:overlay];
    [self.pager setValue:overlay forKey:@"topOverlayView"];
    [self.pager setValue:@50 forKey:@"topOverlayHeight"];
    [self.pager setValue:@100 forKey:@"headerHeight"];
    [self.pager setValue:@20 forKey:@"stickyHeaderHeight"];
    [self.pager setValue:@YES forKey:@"nativeSmoothHeaderScrollEnabled"];
    [self.pager setValue:@YES forKey:@"topScrollEdgeEnabled"];
    [self.pager setValue:@(static_cast<NSInteger>(RNCCollapsiblePagerViewTopScrollEdgeEffect::Hard))
                 forKey:@"topScrollEdgeEffect"];
    [self.pager setValue:scroll forKey:@"observedScrollView"];
    [self.pager setValue:scroll forKey:@"sharedHeaderScrollView"];
    scroll.contentOffset = CGPointMake(0, -170);
    [self.pager updateTopScrollEdgeForScrollView:scroll];
    CALayer *layer = [self.pager valueForKey:@"topOverlayThemeBackgroundLayer"];
    XCTAssertNotNil(layer);
    XCTAssertEqual(layer.superlayer, overlayHost.layer);
    XCTAssertEqualWithAccuracy(layer.opacity, 1, 0.01);
    XCTAssertEqual(scroll.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);
    XCTAssertEqual([self.pager valueForKey:@"topEdgeScrollView"], scroll);

    scroll.contentOffset = CGPointMake(0, -120);
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertEqualWithAccuracy(layer.opacity, 0.5, 0.01);
    scroll.contentOffset = CGPointMake(0, -70);
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertEqualWithAccuracy(layer.opacity, 0, 0.01);
    scroll.contentOffset = CGPointMake(0, -210);
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertEqualWithAccuracy(layer.opacity, 1, 0.01);

    scroll.contentInset = UIEdgeInsetsMake(230, 0, 0, 0);
    scroll.contentOffset = CGPointMake(0, -230);
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertEqualWithAccuracy(layer.opacity, 1, 0.01);
    self.pager.backgroundColor = UIColor.whiteColor;
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertTrue(CGColorEqualToColor(layer.backgroundColor, UIColor.whiteColor.CGColor));

    [self.pager updateTopScrollEdgeForScrollView:nil];
    XCTAssertEqual([self.pager valueForKey:@"topOverlayThemeBackgroundLayer"], layer);
    XCTAssertEqualWithAccuracy(layer.opacity, 1, 0.01);
    [self.pager setValue:@YES forKey:@"topScrollEdgeEnabled"];
    [self.pager updateTopScrollEdgeForScrollView:scroll];
    [self.pager setValue:@123 forKey:@"externalTopOverlayTag"];
    [self.pager updateScrollEdgeContentMasks];
    XCTAssertNil([self.pager valueForKey:@"topOverlayThemeBackgroundLayer"]);
    [self.pager setValue:@0 forKey:@"externalTopOverlayTag"];
    [self.pager updateTopScrollEdgeForScrollView:scroll];
    XCTAssertEqual(scroll.topEdgeEffect.style, UIScrollEdgeEffectStyle.hardStyle);
    [self.pager setValue:@NO forKey:@"topScrollEdgeEnabled"];
    [self.pager updateTopScrollEdgeForScrollView:scroll];
    XCTAssertNil([self.pager valueForKey:@"topOverlayThemeBackgroundLayer"]);
    [self.pager setValue:@YES forKey:@"topScrollEdgeEnabled"];
    [self.pager updateTopScrollEdgeForScrollView:scroll];
    XCTAssertNotNil([self.pager valueForKey:@"topOverlayThemeBackgroundLayer"]);
    [self.pager prepareForRecycle];
    XCTAssertNil([self.pager valueForKey:@"topOverlayThemeBackgroundLayer"]);
  } else {
    XCTSkip(@"The theme background applies only on iOS 27 or newer");
  }
}

@end