Refactor FXIOS-10541 [Homepage Rebuild] Add scrolling logic to the ne…

…w homepage (#23758)

Add scrolling logic to new homepage

firefox-ios/Client/Coordinators/Browser/BrowserCoordinator.swift

@@ -160,6 +160,7 @@ class BrowserCoordinator: BaseCoordinator,
             return
         }
         self.homepageViewController = homepageController
+        homepageController.scrollToTop()
     }
 
     func showPrivateHomepage(overlayManager: OverlayModeManager) {

firefox-ios/Client/Frontend/Home/Homepage Rebuild/HomepageViewController.swift

@@ -5,9 +5,11 @@
 import Foundation
 import Common
 import Redux
+import Shared
 
 final class HomepageViewController: UIViewController,
                                     UICollectionViewDelegate,
+                                    FeatureFlaggable,
                                     ContentContainable,
                                     Themeable,
                                     Notifiable,
@@ -46,6 +48,7 @@ final class HomepageViewController: UIViewController,
     private var overlayManager: OverlayModeManager
     private var logger: Logger
     private var homepageState: HomepageState
+    private var lastContentOffsetY: CGFloat = 0
 
     private var currentTheme: Theme {
         themeManager.getCurrentTheme(for: windowUUID)
@@ -123,7 +126,25 @@ final class HomepageViewController: UIViewController,
         wallpaperView.updateImageForOrientationChange()
     }
 
+    // called when the homepage is displayed to make sure it's scrolled to top
+    func scrollToTop(animated: Bool = false) {
+        collectionView?.setContentOffset(.zero, animated: animated)
+        if let collectionView = collectionView {
+            handleScroll(collectionView, isUserInteraction: false)
+        }
+    }
+
     func scrollViewDidScroll(_ scrollView: UIScrollView) {
+        handleScroll(scrollView, isUserInteraction: true)
+    }
+
+    func scrollViewWillBeginDragging(_ scrollView: UIScrollView) {
+        lastContentOffsetY = scrollView.contentOffset.y
+        handleToolbarStateOnScroll()
+    }
+
+    private func handleScroll(_ scrollView: UIScrollView, isUserInteraction: Bool) {
+        // We only handle status bar overlay alpha if there's a wallpaper applied on the homepage
         if homepageState.wallpaperState.wallpaperConfiguration.hasImage {
             let theme = themeManager.getCurrentTheme(for: windowUUID)
             statusBarScrollDelegate?.scrollViewDidScroll(
@@ -132,6 +153,37 @@ final class HomepageViewController: UIViewController,
                 theme: theme
             )
         }
+        // this action controls the address toolbar's border position, and to prevent spamming redux with actions for every
+        // change in content offset, we keep track of lastContentOffsetY to know if the border needs to be updated
+        if (lastContentOffsetY > 0 && scrollView.contentOffset.y <= 0) ||
+            (lastContentOffsetY <= 0 && scrollView.contentOffset.y > 0) {
+            lastContentOffsetY = scrollView.contentOffset.y
+            store.dispatch(
+                GeneralBrowserMiddlewareAction(
+                    scrollOffset: scrollView.contentOffset,
+                    windowUUID: windowUUID,
+                    actionType: GeneralBrowserMiddlewareActionType.websiteDidScroll))
+        }
+    }
+
+    private func handleToolbarStateOnScroll() {
+        // TODO: FXIOS-10877 This logic will be handled by toolbar state, the homepage will just dispatch the action
+        let toolbarState = store.state.screenState(ToolbarState.self, for: .toolbar, window: windowUUID)
+
+        // Only dispatch action when user is in edit mode to avoid having the toolbar re-displayed
+        if featureFlags.isFeatureEnabled(.toolbarRefactor, checking: .buildOnly),
+           let toolbarState,
+           toolbarState.addressToolbar.isEditing {
+            // When the user scrolls the homepage (not overlaid on a webpage when searching) we cancel edit mode
+            // On a website we just dismiss the keyboard
+            if toolbarState.addressToolbar.url == nil {
+                let action = ToolbarAction(windowUUID: windowUUID, actionType: ToolbarActionType.cancelEdit)
+                store.dispatch(action)
+            } else {
+                let action = ToolbarAction(windowUUID: windowUUID, actionType: ToolbarActionType.hideKeyboard)
+                store.dispatch(action)
+            }
+        }
     }
 
     // MARK: - Redux

firefox-ios/firefox-ios-tests/Tests/ClientTests/Frontend/Homepage Rebuild/HomepageViewControllerTests.swift

@@ -7,20 +7,23 @@ import Common
 
 @testable import Client
 
-final class HomepageViewControllerTests: XCTestCase {
+final class HomepageViewControllerTests: XCTestCase, StoreTestUtility {
     let windowUUID: WindowUUID = .XCTestDefaultUUID
     var mockNotificationCenter: MockNotificationCenter?
     var mockThemeManager: MockThemeManager?
+    var mockStore: MockStoreForMiddleware<AppState>!
 
     override func setUp() {
         super.setUp()
         DependencyHelperMock().bootstrapDependencies()
+        setupStore()
     }
 
     override func tearDown() {
         mockNotificationCenter = nil
         mockThemeManager = nil
         DependencyHelperMock().reset()
+        resetStore()
         super.tearDown()
     }
 
@@ -97,6 +100,50 @@ final class HomepageViewControllerTests: XCTestCase {
         XCTAssertEqual(mockStatusBarScrollDelegate.savedScrollView, scrollView)
     }
 
+    func test_scrollToTop_updatesStatusBarScrollDelegate_andSetsCollectionViewOffset() {
+        let mockStatusBarScrollDelegate = MockStatusBarScrollDelegate()
+        let homepageVC = createSubject(statusBarScrollDelegate: mockStatusBarScrollDelegate)
+       let wallpaperConfiguration = WallpaperConfiguration(hasImage: true)
+        let newState = HomepageState.reducer(
+            HomepageState(windowUUID: .XCTestDefaultUUID),
+            WallpaperAction(
+                wallpaperConfiguration: wallpaperConfiguration,
+                windowUUID: .XCTestDefaultUUID,
+                actionType: WallpaperMiddlewareActionType.wallpaperDidInitialize
+            )
+        )
+
+        guard let collectionView = homepageVC.view.subviews.first(where: {
+            $0 is UICollectionView
+        }) as? UICollectionView else {
+            XCTFail()
+            return
+        }
+
+        homepageVC.newState(state: newState)
+        homepageVC.scrollToTop()
+
+        XCTAssertEqual(collectionView.contentOffset, .zero)
+        XCTAssertEqual(mockStatusBarScrollDelegate.savedScrollView, collectionView)
+    }
+
+    func test_scrollViewDidScroll_TriggersGeneralBrowserMiddlewareAction() throws {
+        let mockStatusBarScrollDelegate = MockStatusBarScrollDelegate()
+        let homepageVC = createSubject(statusBarScrollDelegate: mockStatusBarScrollDelegate)
+        let scrollView = UIScrollView()
+        scrollView.contentOffset.y = 10
+
+        homepageVC.scrollViewDidScroll(scrollView)
+
+        let actionCalled = try XCTUnwrap(
+            mockStore.dispatchedActions.first(where: {
+                $0 is GeneralBrowserMiddlewareAction
+            }) as? GeneralBrowserMiddlewareAction
+        )
+        let actionType = try XCTUnwrap(actionCalled.actionType as? GeneralBrowserMiddlewareActionType)
+        XCTAssertEqual(actionType, GeneralBrowserMiddlewareActionType.websiteDidScroll)
+    }
+
     private func createSubject(statusBarScrollDelegate: StatusBarScrollDelegate? = nil) -> HomepageViewController {
         let notificationCenter = MockNotificationCenter()
         let themeManager = MockThemeManager()
@@ -113,4 +160,17 @@ final class HomepageViewControllerTests: XCTestCase {
         trackForMemoryLeaks(homepageViewController)
         return homepageViewController
     }
+
+    func setupAppState() -> Client.AppState {
+        return AppState()
+    }
+
+    func setupStore() {
+        mockStore = MockStoreForMiddleware(state: setupAppState())
+        StoreTestUtilityHelper.setupStore(with: mockStore)
+    }
+
+    func resetStore() {
+        StoreTestUtilityHelper.resetStore()
+    }
 }