Estimate status cell heights

Extensions/CollectionItem+Extensions.swift

@@ -25,4 +25,17 @@ extension CollectionItem {
             return ConversationListCell.self
         }
     }
+
+    func estimatedHeight(width: CGFloat, identification: Identification) -> CGFloat {
+        switch self {
+        case let .status(status, configuration):
+            return StatusView.estimatedHeight(
+                width: width,
+                identification: identification,
+                status: status,
+                configuration: configuration)
+        default:
+            return UITableView.automaticDimension
+        }
+    }
 }

Extensions/String+Extensions.swift

@@ -4,6 +4,15 @@ import Mastodon
 import UIKit
 
 extension String {
+    func height(width: CGFloat, font: UIFont) -> CGFloat {
+        (self as NSString).boundingRect(
+            with: CGSize(width: width, height: .greatestFiniteMagnitude),
+            options: .usesLineFragmentOrigin,
+            attributes: [.font: font],
+            context: nil)
+            .height
+    }
+
     func countEmphasizedAttributedString(count: Int, highlighted: Bool = false) -> NSAttributedString {
         let countRange = (self as NSString).range(of: String.localizedStringWithFormat("%ld", count))
 

View Controllers/TableViewController.swift

@@ -110,7 +110,9 @@ class TableViewController: UITableViewController {
     override func tableView(_ tableView: UITableView, estimatedHeightForRowAt indexPath: IndexPath) -> CGFloat {
         guard let item = dataSource.itemIdentifier(for: indexPath) else { return UITableView.automaticDimension }
 
-        return cellHeightCaches[tableView.frame.width]?[item] ?? UITableView.automaticDimension
+        return cellHeightCaches[tableView.frame.width]?[item]
+            ?? item.estimatedHeight(width: tableView.readableContentGuide.layoutFrame.width,
+                                    identification: identification)
     }
 
     override func tableView(_ tableView: UITableView, shouldHighlightRowAt indexPath: IndexPath) -> Bool {

Views/AttachmentsView.swift

@@ -1,6 +1,7 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
 import Combine
+import Mastodon
 import UIKit
 import ViewModels
 
@@ -80,6 +81,20 @@ final class AttachmentsView: UIView {
 }
 
 extension AttachmentsView {
+    static func estimatedHeight(width: CGFloat,
+                                identification: Identification,
+                                status: Status,
+                                configuration: CollectionItem.StatusConfiguration) -> CGFloat {
+        let height: CGFloat
+        if status.displayStatus.mediaAttachments.count == 1,
+           let aspectRatio = status.mediaAttachments.first?.aspectRatio {
+            height = width / max(CGFloat(aspectRatio), 16 / 9)
+        } else {
+            height = width / (16 / 9)
+        }
+
+        return height
+    }
     var shouldAutoplay: Bool {
         guard !isHidden, let viewModel = viewModel, viewModel.shouldShowAttachments else { return false }
 

Views/PollOptionButton.swift

@@ -41,6 +41,12 @@ final class PollOptionButton: UIButton {
     }
 }
 
+extension PollOptionButton {
+    static func estimatedHeight(width: CGFloat, title: String) -> CGFloat {
+        title.height(width: width, font: .preferredFont(forTextStyle: .callout))
+    }
+}
+
 private extension PollOptionButton {
     static let titleEdgeInsets = UIEdgeInsets(top: 0, left: .compactSpacing, bottom: 0, right: .compactSpacing)
 }

Views/PollResultView.swift

@@ -74,6 +74,14 @@ final class PollResultView: UIView {
     }
 }
 
+extension PollResultView {
+    static func estimatedHeight(width: CGFloat, title: String) -> CGFloat {
+        title.height(width: width, font: .preferredFont(forTextStyle: .callout))
+            + .compactSpacing
+            + 4 // progress view height
+    }
+}
+
 private extension PollResultView {
     private static var percentFormatter: NumberFormatter = {
         let percentageFormatter = NumberFormatter()

Views/PollView.swift

@@ -1,6 +1,7 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
 import Combine
+import Mastodon
 import UIKit
 import ViewModels
 
@@ -112,6 +113,34 @@ final class PollView: UIView {
 }
 
 extension PollView {
+    static func estimatedHeight(width: CGFloat,
+                                identification: Identification,
+                                status: Status,
+                                configuration: CollectionItem.StatusConfiguration) -> CGFloat {
+        if let poll = status.displayStatus.poll {
+            var height: CGFloat = 0
+            let open = !poll.expired && !poll.voted
+
+            for option in poll.options {
+                height += open ? PollOptionButton.estimatedHeight(width: width, title: option.title)
+                    : PollResultView.estimatedHeight(width: width, title: option.title)
+                height += .defaultSpacing
+            }
+
+            if open {
+                height += .minimumButtonDimension + .defaultSpacing
+            }
+
+            height += .minimumButtonDimension / 2
+
+            return height
+        } else {
+            return 0
+        }
+    }
+}
+
+private extension PollView {
     func initialSetup() {
         addSubview(stackView)
         stackView.translatesAutoresizingMaskIntoConstraints = false
@@ -146,11 +175,20 @@ extension PollView {
 
         bottomStackView.addArrangedSubview(UIView())
 
+        let voteButtonHeightConstraint = voteButton.heightAnchor.constraint(equalToConstant: .minimumButtonDimension)
+        let refreshButtonHeightConstraint = refreshButton.heightAnchor.constraint(
+            equalToConstant: .minimumButtonDimension / 2)
+
+        refreshButtonHeightConstraint.priority = .justBelowMax
+        refreshButtonHeightConstraint.priority = .justBelowMax
+
         NSLayoutConstraint.activate([
             stackView.leadingAnchor.constraint(equalTo: leadingAnchor),
             stackView.topAnchor.constraint(equalTo: topAnchor),
             stackView.trailingAnchor.constraint(equalTo: trailingAnchor),
-            stackView.bottomAnchor.constraint(equalTo: bottomAnchor)
+            stackView.bottomAnchor.constraint(equalTo: bottomAnchor),
+            voteButtonHeightConstraint,
+            refreshButtonHeightConstraint
         ])
     }
 }

Views/Status/CardView.swift

@@ -1,6 +1,7 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
 import Kingfisher
+import Mastodon
 import UIKit
 import ViewModels
 
@@ -44,6 +45,23 @@ final class CardView: UIView {
     }
 }
 
+extension CardView {
+    static func estimatedHeight(width: CGFloat,
+                                identification: Identification,
+                                status: Status,
+                                configuration: CollectionItem.StatusConfiguration) -> CGFloat {
+        if status.displayStatus.card != nil {
+            return round(UIFont.preferredFont(forTextStyle: .headline).lineHeight
+                            + UIFont.preferredFont(forTextStyle: .subheadline).lineHeight
+                            + UIFont.preferredFont(forTextStyle: .footnote).lineHeight
+                            + .defaultSpacing * 2
+                            + .compactSpacing * 2)
+        } else {
+            return 0
+        }
+    }
+}
+
 private extension CardView {
     // swiftlint:disable:next function_body_length
     func initialSetup() {

Views/Status/StatusBodyView.swift

@@ -1,5 +1,6 @@
 // Copyright © 2020 Metabolist. All rights reserved.
 
+import Mastodon
 import UIKit
 import ViewModels
 
@@ -49,7 +50,7 @@ final class StatusBodyView: UIView {
             attachmentsView.isHidden = viewModel.attachmentViewModels.isEmpty
             attachmentsView.viewModel = viewModel
 
-            pollView.isHidden = viewModel.pollOptions.isEmpty
+            pollView.isHidden = viewModel.pollOptions.isEmpty || !viewModel.shouldShowContent
             pollView.viewModel = viewModel
 
             cardView.viewModel = viewModel.cardViewModel
@@ -69,6 +70,64 @@ final class StatusBodyView: UIView {
     }
 }
 
+extension StatusBodyView {
+    static func estimatedHeight(width: CGFloat,
+                                identification: Identification,
+                                status: Status,
+                                configuration: CollectionItem.StatusConfiguration) -> CGFloat {
+        let contentFont = UIFont.preferredFont(forTextStyle: configuration.isContextParent ? .title3 : .callout)
+        var height: CGFloat = 0
+
+        var contentHeight = status.displayStatus.content.attributed.string.height(
+            width: width,
+            font: contentFont)
+
+        if status.displayStatus.card != nil {
+            contentHeight += .compactSpacing
+            contentHeight += CardView.estimatedHeight(
+                width: width,
+                identification: identification,
+                status: status,
+                configuration: configuration)
+        }
+
+        if status.displayStatus.poll != nil {
+            contentHeight += .defaultSpacing
+            contentHeight += PollView.estimatedHeight(
+                width: width,
+                identification: identification,
+                status: status,
+                configuration: configuration)
+        }
+
+        if status.displayStatus.spoilerText.isEmpty {
+            height += contentHeight
+        } else {
+            height += status.displayStatus.spoilerText.height(width: width, font: contentFont)
+            height += .compactSpacing
+            height += NSLocalizedString("status.show-more", comment: "").height(
+                width: width,
+                font: .preferredFont(forTextStyle: .headline))
+
+            if configuration.showContentToggled && !identification.identity.preferences.readingExpandSpoilers {
+                height += .compactSpacing
+                height += contentHeight
+            }
+        }
+
+        if !status.displayStatus.mediaAttachments.isEmpty {
+            height += .compactSpacing
+            height += AttachmentsView.estimatedHeight(
+                width: width,
+                identification: identification,
+                status: status,
+                configuration: configuration)
+        }
+
+        return height
+    }
+}
+
 extension StatusBodyView: UITextViewDelegate {
     func textView(
         _ textView: UITextView,

Views/Status/StatusView.swift

@@ -2,6 +2,7 @@
 
 // swiftlint:disable file_length
 import Kingfisher
+import Mastodon
 import UIKit
 import ViewModels
 
@@ -56,6 +57,36 @@ final class StatusView: UIView {
     }
 }
 
+extension StatusView {
+    static func estimatedHeight(width: CGFloat,
+                                identification: Identification,
+                                status: Status,
+                                configuration: CollectionItem.StatusConfiguration) -> CGFloat {
+        var height = CGFloat.defaultSpacing * 2
+        let bodyWidth = width - .defaultSpacing - .avatarDimension
+
+        if status.reblog != nil || configuration.isPinned {
+            height += UIFont.preferredFont(forTextStyle: .caption1).lineHeight + .compactSpacing
+        }
+
+        if configuration.isContextParent {
+            height += .avatarDimension + .minimumButtonDimension * 2.5 + .hairline * 2 + .compactSpacing * 4
+        } else {
+            height += UIFont.preferredFont(forTextStyle: .headline).lineHeight
+                + .compactSpacing + .minimumButtonDimension / 2
+        }
+
+        height += StatusBodyView.estimatedHeight(
+            width: bodyWidth,
+            identification: identification,
+            status: status,
+            configuration: configuration)
+            + .compactSpacing
+
+        return height
+    }
+}
+
 extension StatusView: UIContentView {
     var configuration: UIContentConfiguration {
         get { statusConfiguration }
@@ -142,6 +173,7 @@ private extension StatusView {
         mainStackView.addArrangedSubview(nameAccountContainerStackView)
 
         mainStackView.addArrangedSubview(bodyView)
+        bodyView.tag = 666
 
         contextParentTimeLabel.font = .preferredFont(forTextStyle: .footnote)
         contextParentTimeLabel.adjustsFontForContentSizeCategory = true
@@ -264,7 +296,10 @@ private extension StatusView {
             avatarButton.leadingAnchor.constraint(equalTo: avatarImageView.leadingAnchor),
             avatarButton.topAnchor.constraint(equalTo: avatarImageView.topAnchor),
             avatarButton.bottomAnchor.constraint(equalTo: avatarImageView.bottomAnchor),
-            avatarButton.trailingAnchor.constraint(equalTo: avatarImageView.trailingAnchor)
+            avatarButton.trailingAnchor.constraint(equalTo: avatarImageView.trailingAnchor),
+            contextParentTimeApplicationStackView.heightAnchor.constraint(
+                greaterThanOrEqualToConstant: .minimumButtonDimension / 2),
+            interactionsStackView.heightAnchor.constraint(greaterThanOrEqualToConstant: .minimumButtonDimension)
         ])
     }
 
@@ -374,7 +409,8 @@ private extension StatusView {
             if isContextParent {
                 button.heightAnchor.constraint(equalToConstant: .minimumButtonDimension).isActive = true
             } else {
-                button.heightAnchor.constraint(greaterThanOrEqualToConstant: 0).isActive = true
+                button.heightAnchor.constraint(
+                    greaterThanOrEqualToConstant: .minimumButtonDimension / 2).isActive = true
             }
         }