From 2877534c704cb346628c3c04dcca7a9b87ce8b59 Mon Sep 17 00:00:00 2001
From: "Hedden, Kyle Matthew" <kyle.hedden@verizonwireless.com>
Date: Fri, 8 Mar 2024 16:45:11 -0500
Subject: [PATCH] Hide and show the carousel pager based upon the content size.

---
 .../Atomic/Organisms/Carousel/Carousel.swift  | 20 ++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/MVMCoreUI/Atomic/Organisms/Carousel/Carousel.swift b/MVMCoreUI/Atomic/Organisms/Carousel/Carousel.swift
index 421c2e95..a9fcc040 100644
--- a/MVMCoreUI/Atomic/Organisms/Carousel/Carousel.swift
+++ b/MVMCoreUI/Atomic/Organisms/Carousel/Carousel.swift
@@ -55,6 +55,9 @@ open class Carousel: View {
     /// The view that we use for paging
     public var pagingView: (MoleculeViewProtocol & CarouselPageControlProtocol)?
     
+    /// The pagingView anchor to the bottom of the carousel. Disabled when the pagingView is hidden.
+    public var pagingBottomPin: NSLayoutConstraint?
+    
     /// If the carousel should loop after scrolling past the first and final cells.
     public var loop = false
     
@@ -89,10 +92,16 @@ open class Carousel: View {
         // Go to current cell. layoutIfNeeded is needed otherwise cellForItem returns nil for peaking logic. The dispatch is a sad way to ensure the collection view is ready to be scrolled.
         guard let model = model as? CarouselModel, !model.molecules.isEmpty,
               (model.paging == true || loop == true) else { return }
-        DispatchQueue.main.async {
-            self.collectionView.scrollToItem(at: IndexPath(row: self.currentIndex, section: 0), at: self.itemAlignment, animated: false)
-            self.collectionView.layoutIfNeeded()
-            self.showPeaking(true)
+        DispatchQueue.main.async { [self] in
+            collectionView.scrollToItem(at: IndexPath(row: currentIndex, section: 0), at: itemAlignment, animated: false)
+            collectionView.layoutIfNeeded()
+            showPeaking(true)
+            
+            let shouldHidePager = model.molecules.isEmpty || collectionView.contentSize.width < bounds.width
+            if let pagingView = pagingView, shouldHidePager != pagingView.isHidden {
+                pagingView.isHidden = shouldHidePager
+                pagingBottomPin?.isActive = !shouldHidePager
+            }
         }
     }
     
@@ -276,7 +285,8 @@ open class Carousel: View {
         addSubview(pagingView)
         pagingView.centerXAnchor.constraint(equalTo: collectionView.centerXAnchor).isActive = true
         collectionView.bottomAnchor.constraint(equalTo: pagingView.centerYAnchor, constant: position).isActive = true
-        bottomAnchor.constraint(greaterThanOrEqualTo: pagingView.bottomAnchor).isActive = true
+        pagingBottomPin = bottomAnchor.constraint(greaterThanOrEqualTo: pagingView.bottomAnchor)
+        pagingBottomPin?.isActive = true
         bottomPin = bottomAnchor.constraint(equalTo: collectionView.bottomAnchor)
         bottomPin?.priority = .defaultLow
         bottomPin?.isActive = true