metatext/Views/UIKit/AttachmentsView.swift
2021-03-20 14:22:04 -07:00

226 lines
10 KiB
Swift

// Copyright © 2020 Metabolist. All rights reserved.
import Combine
import Mastodon
import UIKit
import ViewModels
final class AttachmentsView: UIView {
private let containerStackView = UIStackView()
private let leftStackView = UIStackView()
private let rightStackView = UIStackView()
private let curtain = UIVisualEffectView(effect: UIBlurEffect(style: .systemMaterial))
private let curtainButton = UIButton(type: .system)
private let hideButtonBackground = UIVisualEffectView(effect: UIBlurEffect(style: .systemMaterial))
private let hideButton = UIButton()
private var aspectRatioConstraint: NSLayoutConstraint?
private var cancellables = Set<AnyCancellable>()
var viewModel: AttachmentsRenderingViewModel? {
didSet {
for stackView in [leftStackView, rightStackView] {
for view in stackView.arrangedSubviews {
stackView.removeArrangedSubview(view)
view.removeFromSuperview()
}
}
guard let viewModel = viewModel else { return }
rightStackView.isHidden = viewModel.attachmentViewModels.count == 1
for (index, attachmentViewModel) in viewModel.attachmentViewModels.enumerated() {
let attachmentView = AttachmentView(viewModel: attachmentViewModel, parentViewModel: viewModel)
attachmentView.playing = viewModel.shouldShowAttachments && attachmentViewModel.shouldAutoplay
attachmentView.removeButton.isHidden = !viewModel.canRemoveAttachments
attachmentView.isAccessibilityElement = !viewModel.canRemoveAttachments
if viewModel.attachmentViewModels.count == 2 && index == 1
|| viewModel.attachmentViewModels.count == 3 && index != 0
|| viewModel.attachmentViewModels.count > 3 && index % 2 != 0 {
rightStackView.addArrangedSubview(attachmentView)
} else {
leftStackView.addArrangedSubview(attachmentView)
}
}
let newAspectRatio: CGFloat
if viewModel.attachmentViewModels.count == 1,
let aspectRatio = viewModel.attachmentViewModels.first?.attachment.aspectRatio {
newAspectRatio = max(CGFloat(aspectRatio), 16 / 9)
} else {
newAspectRatio = 16 / 9
}
aspectRatioConstraint?.isActive = false
aspectRatioConstraint = widthAnchor.constraint(equalTo: heightAnchor, multiplier: newAspectRatio)
aspectRatioConstraint?.priority = .justBelowMax
aspectRatioConstraint?.isActive = true
curtain.isHidden = viewModel.shouldShowAttachments
curtainButton.setTitle(
NSLocalizedString((viewModel.sensitive)
? "attachment.sensitive-content"
: "attachment.media-hidden",
comment: ""),
for: .normal)
hideButtonBackground.isHidden = !viewModel.shouldShowHideAttachmentsButton
if curtain.isHidden {
let type: Attachment.AttachmentType
if viewModel.attachmentViewModels
.allSatisfy({ $0.attachment.type == .image || $0.attachment.type == .gifv }) {
type = .image
} else if viewModel.attachmentViewModels.allSatisfy({ $0.attachment.type == .video }) {
type = .video
} else if viewModel.attachmentViewModels.allSatisfy({ $0.attachment.type == .audio }) {
type = .audio
} else {
type = .unknown
}
var accessibilityLabel = type.accessibilityNames(count: viewModel.attachmentViewModels.count)
for attachmentViewModel in viewModel.attachmentViewModels {
guard let description = attachmentViewModel.attachment.description,
!description.isEmpty
else { continue }
accessibilityLabel.appendWithSeparator(attachmentViewModel.attachment.type.accessibilityName)
accessibilityLabel.appendWithSeparator(description)
}
self.accessibilityLabel = accessibilityLabel
} else {
accessibilityLabel = curtainButton.title(for: .normal)
}
}
}
override init(frame: CGRect) {
super.init(frame: frame)
initialSetup()
}
@available(*, unavailable)
required init?(coder: NSCoder) {
fatalError("init(coder:) has not been implemented")
}
}
extension AttachmentsView {
static func estimatedHeight(width: CGFloat,
identityContext: IdentityContext,
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 }
return viewModel.attachmentViewModels.allSatisfy(\.shouldAutoplay)
}
var attachmentViewAccessibilityCustomActions: [UIAccessibilityCustomAction] {
attachmentViews.compactMap { attachmentView in
guard let accessibilityLabel = attachmentView.accessibilityLabel else { return nil }
return UIAccessibilityCustomAction(name: accessibilityLabel) { _ in
attachmentView.selectAttachment()
return true
}
}
}
}
private extension AttachmentsView {
// swiftlint:disable:next function_body_length
func initialSetup() {
backgroundColor = .clear
layoutMargins = .zero
clipsToBounds = true
layer.cornerRadius = .defaultCornerRadius
addSubview(containerStackView)
containerStackView.translatesAutoresizingMaskIntoConstraints = false
containerStackView.distribution = .fillEqually
containerStackView.spacing = .compactSpacing
leftStackView.distribution = .fillEqually
leftStackView.spacing = .compactSpacing
leftStackView.axis = .vertical
rightStackView.distribution = .fillEqually
rightStackView.spacing = .compactSpacing
rightStackView.axis = .vertical
containerStackView.addArrangedSubview(leftStackView)
containerStackView.addArrangedSubview(rightStackView)
let toggleShowAttachmentsAction = UIAction { [weak self] _ in
self?.viewModel?.toggleShowAttachments()
}
addSubview(hideButtonBackground)
hideButtonBackground.translatesAutoresizingMaskIntoConstraints = false
hideButtonBackground.clipsToBounds = true
hideButtonBackground.layer.cornerRadius = .defaultCornerRadius
hideButton.addAction(toggleShowAttachmentsAction, for: .touchUpInside)
hideButtonBackground.contentView.addSubview(hideButton)
hideButton.translatesAutoresizingMaskIntoConstraints = false
hideButton.setImage(
UIImage(systemName: "eye.slash", withConfiguration: UIImage.SymbolConfiguration(scale: .medium)),
for: .normal)
addSubview(curtain)
curtain.translatesAutoresizingMaskIntoConstraints = false
curtain.contentView.addSubview(curtainButton)
curtainButton.addAction(toggleShowAttachmentsAction, for: .touchUpInside)
curtainButton.translatesAutoresizingMaskIntoConstraints = false
curtainButton.titleLabel?.font = .preferredFont(forTextStyle: .headline)
curtainButton.titleLabel?.adjustsFontForContentSizeCategory = true
NSLayoutConstraint.activate([
containerStackView.leadingAnchor.constraint(equalTo: leadingAnchor),
containerStackView.trailingAnchor.constraint(equalTo: trailingAnchor),
containerStackView.topAnchor.constraint(equalTo: topAnchor),
containerStackView.bottomAnchor.constraint(equalTo: bottomAnchor),
hideButtonBackground.topAnchor.constraint(equalTo: topAnchor, constant: .defaultSpacing),
hideButtonBackground.leadingAnchor.constraint(equalTo: leadingAnchor, constant: .defaultSpacing),
hideButton.topAnchor.constraint(
equalTo: hideButtonBackground.contentView.topAnchor,
constant: .compactSpacing),
hideButton.leadingAnchor.constraint(
equalTo: hideButtonBackground.contentView.leadingAnchor,
constant: .compactSpacing),
hideButtonBackground.contentView.trailingAnchor.constraint(
equalTo: hideButton.trailingAnchor,
constant: .compactSpacing),
hideButtonBackground.contentView.bottomAnchor.constraint(
equalTo: hideButton.bottomAnchor,
constant: .compactSpacing),
curtain.topAnchor.constraint(equalTo: topAnchor),
curtain.leadingAnchor.constraint(equalTo: leadingAnchor),
curtain.trailingAnchor.constraint(equalTo: trailingAnchor),
curtain.bottomAnchor.constraint(equalTo: bottomAnchor),
curtainButton.topAnchor.constraint(equalTo: curtain.contentView.topAnchor),
curtainButton.leadingAnchor.constraint(equalTo: curtain.contentView.leadingAnchor),
curtainButton.trailingAnchor.constraint(equalTo: curtain.contentView.trailingAnchor),
curtainButton.bottomAnchor.constraint(equalTo: curtain.contentView.bottomAnchor)
])
}
var attachmentViews: [AttachmentView] {
(leftStackView.arrangedSubviews + rightStackView.arrangedSubviews)
.compactMap { $0 as? AttachmentView }
}
}