Show lemniscate for queued goals

BeeSwift.xcodeproj/project.pbxproj

@@ -49,6 +49,8 @@
 		E41286F12A62E6840093D598 /* KeychainSwift in Frameworks */ = {isa = PBXBuildFile; productRef = E41286F02A62E6840093D598 /* KeychainSwift */; };
 		E41286F32A62E97B0093D598 /* KeychainSwift in Frameworks */ = {isa = PBXBuildFile; productRef = E41286F22A62E97B0093D598 /* KeychainSwift */; };
 		E41286F52A62E9840093D598 /* KeychainSwift in Frameworks */ = {isa = PBXBuildFile; productRef = E41286F42A62E9840093D598 /* KeychainSwift */; };
+		E412DADF2B869E1E0099E483 /* BeeLemniscateView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E412DADE2B869E1E0099E483 /* BeeLemniscateView.swift */; };
+		E412DAE12B86A8F70099E483 /* GoalImageView.swift in Sources */ = {isa = PBXBuildFile; fileRef = E412DAE02B86A8F70099E483 /* GoalImageView.swift */; };
 		E417572D2A6446FE0029CDDA /* CurrentUserManagerTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = E417572C2A6446FE0029CDDA /* CurrentUserManagerTests.swift */; };
 		E43833942AC1473E0098A38F /* InlineDatePicker.swift in Sources */ = {isa = PBXBuildFile; fileRef = E43833932AC1473E0098A38F /* InlineDatePicker.swift */; };
 		E43BEA842A036A9C00FC3A38 /* LogReader.swift in Sources */ = {isa = PBXBuildFile; fileRef = E43BEA832A036A9C00FC3A38 /* LogReader.swift */; };
@@ -313,6 +315,8 @@
 		A1F9D1E9211B9B7600E2BC93 /* EditDatapointViewController.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = EditDatapointViewController.swift; sourceTree = "<group>"; };
 		E4040D732A7B5F0E008E7D0E /* WorkoutMinutesHealthKitMetric.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = WorkoutMinutesHealthKitMetric.swift; sourceTree = "<group>"; };
 		E41286ED2A62DF330093D598 /* BeeminderModel.xcdatamodel */ = {isa = PBXFileReference; lastKnownFileType = wrapper.xcdatamodel; path = BeeminderModel.xcdatamodel; sourceTree = "<group>"; };
+		E412DADE2B869E1E0099E483 /* BeeLemniscateView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = BeeLemniscateView.swift; sourceTree = "<group>"; };
+		E412DAE02B86A8F70099E483 /* GoalImageView.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = GoalImageView.swift; sourceTree = "<group>"; };
 		E417572C2A6446FE0029CDDA /* CurrentUserManagerTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = CurrentUserManagerTests.swift; sourceTree = "<group>"; };
 		E42CB451291727B200A35AB9 /* HealthKitError.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = HealthKitError.swift; sourceTree = "<group>"; };
 		E43833932AC1473E0098A38F /* InlineDatePicker.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = InlineDatePicker.swift; sourceTree = "<group>"; };
@@ -640,6 +644,8 @@
 				E43D9AFA2929C37D00FC1578 /* DatapointValueAccessory.swift */,
 				E43833932AC1473E0098A38F /* InlineDatePicker.swift */,
 				E46DC80E2AA58DF20059FDFE /* PullToRefreshHint.swift */,
+				E412DADE2B869E1E0099E483 /* BeeLemniscateView.swift */,
+				E412DAE02B86A8F70099E483 /* GoalImageView.swift */,
 			);
 			path = Components;
 			sourceTree = "<group>";
@@ -1147,11 +1153,13 @@
 				E55760F526549D310076B95A /* AddDataIntentHandler.swift in Sources */,
 				E5C9EFE62612E02700DBBEAE /* AddDataIntents.intentdefinition in Sources */,
 				A10DC2DF207BFCBA00FB7B3A /* RemoveHKMetricViewController.swift in Sources */,
+				E412DAE12B86A8F70099E483 /* GoalImageView.swift in Sources */,
 				A1619EA41BEECC1500E14B3A /* EditDefaultNotificationsViewController.swift in Sources */,
 				A149B3701AEF528C00F19A09 /* SettingsViewController.swift in Sources */,
 				E46DC80F2AA58DF20059FDFE /* PullToRefreshHint.swift in Sources */,
 				A1E618E21E78158700D8ED93 /* HealthKitConfigViewController.swift in Sources */,
 				E4B0833B2934620500A71564 /* DatapointTableViewController.swift in Sources */,
+				E412DADF2B869E1E0099E483 /* BeeLemniscateView.swift in Sources */,
 				A11BC2D91FFAD5BC00E56064 /* TimerViewController.swift in Sources */,
 				A1EA154D1B01E6EC0052A6E6 /* DatapointTableViewCell.swift in Sources */,
 				A11A87C61FEBFF7200A43E47 /* ChooseGoalSortViewController.swift in Sources */,

BeeSwift/Components/BeeLemniscateView.swift

@@ -0,0 +1,83 @@
+import Foundation
+import SpriteKit
+
+/// An animated bee following a lemniscate (figure-eight) pattern.
+/// Used to indicate server-side asynchronous work is taking place.
+class BeeLemniscateView : UIView {
+    private let sceneContainer = SKView()
+    private let scene = SKScene()
+    private let beeSprite = SKSpriteNode(imageNamed: "Infinibee")
+
+    private let SpriteRelativeSize = 0.15
+    private let LemniscateAspectRatio = 1.25
+    private let LemniscateMaxHeight = 0.8
+    private let LemniscateMaxWidth = 0.6
+
+    init() {
+        super.init(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
+        setupView()
+    }
+
+    required init?(coder: NSCoder) {
+        super.init(coder: coder)
+        setupView()
+    }
+
+    private func setupView() {
+        self.addSubview(sceneContainer)
+        sceneContainer.snp.makeConstraints { (make) in
+            make.edges.equalToSuperview()
+        }
+        sceneContainer.allowsTransparency = true
+
+        scene.backgroundColor = .clear
+        scene.addChild(beeSprite)
+
+        sceneContainer.presentScene(scene)
+    }
+
+    override func layoutSubviews() {
+        super.layoutSubviews()
+
+        // Resize the scene to match the container layout
+        scene.size = sceneContainer.bounds.size
+
+        // Rescale the bee sprite
+        let desiredSpriteWidth = scene.size.width * SpriteRelativeSize
+        let scaleFactor = desiredSpriteWidth / beeSprite.size.width
+        beeSprite.setScale(scaleFactor)
+
+        // Calculate the bounding box for the lemniscate control points
+        let maximumHeightForHeight = scene.size.height * LemniscateMaxHeight
+        let maximumHeightForWidth = scene.size.width * LemniscateMaxWidth / LemniscateAspectRatio
+
+        let height = min(maximumHeightForWidth, maximumHeightForHeight)
+        let width = height * LemniscateAspectRatio
+
+        let lemniscateBounds = CGRect(
+            x: (scene.size.width - width) / 2, y: (scene.size.height - height) / 2,
+            width: width, height: height
+        )
+        let centerPoint = CGPoint(x: lemniscateBounds.midX, y: lemniscateBounds.midY)
+
+        // Create a path for the sprite to follow
+        let path = CGMutablePath()
+        path.move(to: centerPoint)
+        path.addCurve(
+            to: centerPoint,
+            control1: CGPoint(x: lemniscateBounds.maxX, y: lemniscateBounds.minY),
+            control2: CGPoint(x: lemniscateBounds.maxX, y: lemniscateBounds.maxY)
+        )
+        path.addCurve(
+            to: centerPoint,
+            control1: CGPoint(x: lemniscateBounds.minX, y: lemniscateBounds.minY),
+            control2: CGPoint(x: lemniscateBounds.minX, y: lemniscateBounds.maxY)
+        )
+
+        let followPath = SKAction.follow(path, asOffset: false, orientToPath: true, duration: 2.0)
+        let followPathForever = SKAction.repeatForever(followPath)
+
+        // Configure the sprite to follow the path
+        beeSprite.run(followPathForever)
+    }
+}

BeeSwift/Components/GoalImageView.swift

@@ -0,0 +1,145 @@
+import Foundation
+import OSLog
+
+import Alamofire
+import AlamofireImage
+
+import BeeKit
+
+/// Shows the current graph for a goal
+/// Handles placeholders for loading and queued states, and automatically updates when the goal changes
+class GoalImageView : UIView {
+    private static let downloader = ImageDownloader(imageCache: AutoPurgingImageCache())
+    private let logger = Logger(subsystem: "com.beeminder.com", category: "GoalImageView")
+
+    private let imageView = UIImageView()
+    private let beeLemniscateView = BeeLemniscateView()
+
+    private var currentlyShowingGraph = false
+    private var inProgressDownload: RequestReceipt? = nil
+    private var currentDownloadToken: UUID? = nil
+
+    public let isThumbnail: Bool
+
+    public var goal: Goal? {
+        didSet {
+            // If changed to a different goal, remove any current state
+            if goal !== oldValue {
+                clearGoalGraph()
+            }
+            refresh()
+        }
+    }
+
+    init(isThumbnail: Bool) {
+        self.isThumbnail = isThumbnail
+        super.init(frame: CGRect(x: 0, y: 0, width: 0, height: 0))
+        setupView()
+    }
+
+    required init?(coder: NSCoder) {
+        self.isThumbnail = false
+        super.init(coder: coder)
+        setupView()
+    }
+
+    private func setupView() {
+        self.addSubview(imageView)
+        imageView.snp.makeConstraints { (make) in
+            make.edges.equalToSuperview()
+        }
+        self.imageView.image = UIImage(named: "GraphPlaceholder")
+
+        self.addSubview(beeLemniscateView)
+        beeLemniscateView.snp.makeConstraints { (make) in
+            make.edges.equalToSuperview()
+        }
+        beeLemniscateView.isHidden = true
+
+        NotificationCenter.default.addObserver(
+            forName: NSNotification.Name(rawValue: GoalManager.goalsUpdatedNotificationName),
+            object: nil,
+            queue: OperationQueue.main
+        ) { [weak self] _ in
+            self?.refresh()
+        }
+
+        refresh()
+    }
+
+    private func clearGoalGraph() {
+        imageView.image = UIImage(named: "GraphPlaceholder")
+        currentlyShowingGraph = false
+        beeLemniscateView.isHidden = true
+    }
+
+    private func showGraphImage(image: UIImage) {
+        imageView.image = image
+        currentlyShowingGraph = true
+        beeLemniscateView.isHidden = !(goal?.queued ?? false)
+    }
+
+    private func refresh() {
+        // Invalidate the download token, meaning that any queued download callbacks
+        // will no-op. This avoids race conditions with downloads finishing out of order.
+        let newDownloadToken = UUID()
+        self.currentDownloadToken = newDownloadToken
+
+        if let downloadReceipt = inProgressDownload {
+            GoalImageView.downloader.cancelRequest(with: downloadReceipt)
+            inProgressDownload = nil
+        }
+
+        //  - Deadbeat: Placeholder, no animation
+        if ServiceLocator.currentUserManager.isDeadbeat() {
+            clearGoalGraph()
+            return
+        }
+
+        //  No Goal: Placeholder, no animation
+        guard let goal = self.goal else {
+            clearGoalGraph()
+            return
+        }
+
+        // When queued, we should show a loading indicator over any existing graph,
+        // but not over the placeholder image.
+        if goal.queued ?? false {
+            beeLemniscateView.isHidden = !currentlyShowingGraph
+        }
+
+        // Load the approppriate iamge for the goal
+        let urlString = if isThumbnail {
+            goal.cacheBustingThumbUrl
+        } else {
+            goal.cacheBustingGraphUrl
+        }
+        let request = URLRequest(url: URL(string: urlString)!)
+
+        // Explicitly check the cache to see if the image is already present, and if so set it directly
+        // This avoids flicker when showing images from the cache, which will otherwise briefly show
+        // the placeholder while waiting for the async download callback
+        if let image = GoalImageView.downloader.imageCache?.image(for: request, withIdentifier: nil) {
+            showGraphImage(image: image)
+            return
+        }
+
+        // Download the image and show it once downloaded
+        inProgressDownload = GoalImageView.downloader.download(request, completion: { response in
+            if newDownloadToken != self.currentDownloadToken {
+                // Another refresh has happend since we were enqueued. Skip performing any updates
+                return
+            }
+
+            switch(response.result) {
+            case .success(let image):
+                // Image downloaded. Show it, and have loading indicator match queued state
+                self.showGraphImage(image: image)
+                break;
+            case .failure(let error):
+                self.logger.error("Error downloading goal graph: \(error)")
+                self.clearGoalGraph()
+            }
+        })
+    }
+}

BeeSwift/GoalCollectionViewCell.swift

@@ -14,14 +14,13 @@ class GoalCollectionViewCell: UICollectionViewCell {
     let slugLabel :BSLabel = BSLabel()
     let titleLabel :BSLabel = BSLabel()
     let todaytaLabel :BSLabel = BSLabel()
-    let thumbnailImageView :UIImageView = UIImageView()
+    let thumbnailImageView = GoalImageView(isThumbnail: true)
     let safesumLabel :BSLabel = BSLabel()
     let margin = 8
 
     var goal: Goal? {
         didSet {
-            self.thumbnailImageView.image = nil
-            self.setThumbnailImage()
+            self.thumbnailImageView.goal = goal
             self.titleLabel.text = goal?.title
             self.slugLabel.text = goal?.slug
             self.titleLabel.isHidden = goal?.title == goal?.slug
@@ -87,27 +86,4 @@ class GoalCollectionViewCell: UICollectionViewCell {
     required init?(coder aDecoder: NSCoder) {
         super.init(coder: aDecoder)
     }
-
-    override func prepareForReuse() {
-        super.prepareForReuse()
-
-        self.slugLabel.text = nil
-        self.titleLabel.text = nil
-        self.thumbnailImageView.image = UIImage(named: "ThumbnailPlaceholder")
-        self.safesumLabel.text = nil
-        self.goal = nil
-    }
-
-    func deadbeatChanged() {
-        self.setThumbnailImage()
-    }
-
-    func setThumbnailImage() {
-        guard let _ = self.goal else { return }
-        if ServiceLocator.currentUserManager.isDeadbeat() {
-            self.thumbnailImageView.image = UIImage(named: "ThumbnailPlaceholder")
-        } else {
-            self.thumbnailImageView.af.setImage(withURL: URL(string: self.goal!.cacheBustingThumbUrl)!, placeholderImage: UIImage(named: "ThumbnailPlaceholder"), filter: nil, progress: nil, progressQueue: DispatchQueue.global(), imageTransition: .noTransition, runImageTransitionIfCached: false, completion: nil)
-        }
-    }
 }

BeeSwift/GoalViewController.swift

@@ -24,7 +24,7 @@ class GoalViewController: UIViewController,  UIScrollViewDelegate, DatapointTabl
 
     var goal : Goal!
 
-    fileprivate var goalImageView = UIImageView()
+    fileprivate var goalImageView = GoalImageView(isThumbnail: false)
     fileprivate var datapointTableController = DatapointTableViewController()
     fileprivate var dateTextField = UITextField()
     fileprivate var valueTextField = UITextField()
@@ -114,8 +114,7 @@ class GoalViewController: UIViewController,  UIScrollViewDelegate, DatapointTabl
             make.left.equalTo(self.goalImageScrollView)
             make.right.equalTo(self.goalImageScrollView)
         }
-        self.goalImageView.image = UIImage(named: "GraphPlaceholder")
-
+        self.goalImageView.goal = self.goal
 
         self.scrollView.addSubview(self.deltasLabel)
         self.deltasLabel.snp.makeConstraints { (make) in
@@ -323,9 +322,7 @@ class GoalViewController: UIViewController,  UIScrollViewDelegate, DatapointTabl
 
     override func observeValue(forKeyPath keyPath: String?, of object: Any?, change: [NSKeyValueChangeKey : Any]?, context: UnsafeMutableRawPointer?) {
         if (!ServiceLocator.currentUserManager.signedIn()) { return }
-        if keyPath == "graph_url" {
-            self.setGraphImage()
-        } else if keyPath == "delta_text" || keyPath == "safebump" || keyPath == "safesum" {
+        if keyPath == "delta_text" || keyPath == "safebump" || keyPath == "safesum" {
             self.refreshCountdown()
         }
     }
@@ -396,14 +393,6 @@ class GoalViewController: UIViewController,  UIScrollViewDelegate, DatapointTabl
         self.countdownLabel.text = self.goal.capitalSafesum()
     }
 
-    func setGraphImage() {
-        if ServiceLocator.currentUserManager.isDeadbeat() {
-            self.goalImageView.image = UIImage(named: "GraphPlaceholder")
-        } else {
-            self.goalImageView.af.setImage(withURL: URL(string: self.goal.cacheBustingGraphUrl)!, placeholderImage: UIImage(named: "GraphPlaceholder"), filter: nil, progress: nil, progressQueue: DispatchQueue.global(), imageTransition: .noTransition, runImageTransitionIfCached: false, completion: nil)
-        }
-    }
-
     @objc func goalImageTapped() {
         self.goalImageScrollView.setZoomScale(self.goalImageScrollView.zoomScale == 1.0 ? 2.0 : 1.0, animated: true)
     }
@@ -545,9 +534,6 @@ class GoalViewController: UIViewController,  UIScrollViewDelegate, DatapointTabl
 
         self.refreshCountdown()
         self.deltasLabel.attributedText = self.goal!.attributedDeltaText
-        if (!self.goal.queued!) {
-            self.setGraphImage()
-        }
     }
 
     func viewForZooming(in scrollView: UIScrollView) -> UIView? {

BeeSwift/Images.xcassets/infinibee.imageset/Contents.json

@@ -0,0 +1,21 @@
+{
+  "images" : [
+    {
+      "filename" : "infinibee.svg",
+      "idiom" : "universal",
+      "scale" : "1x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "2x"
+    },
+    {
+      "idiom" : "universal",
+      "scale" : "3x"
+    }
+  ],
+  "info" : {
+    "author" : "xcode",
+    "version" : 1
+  }
+}