Tusker/Tusker/Views/ContentTextView.swift

341 lines
15 KiB
Swift

//
// ContentTextView.swift
// Tusker
//
// Created by Shadowfacts on 1/18/20.
// Copyright © 2020 Shadowfacts. All rights reserved.
//
import UIKit
import SwiftSoup
import Pachyderm
import SafariServices
import WebURL
import WebURLFoundationExtras
private let emojiRegex = try! NSRegularExpression(pattern: ":(\\w+):", options: [])
private let dataDetectorsScheme = "x-apple-data-detectors"
class ContentTextView: LinkTextView, BaseEmojiLabel {
weak var navigationDelegate: TuskerNavigationDelegate?
weak var overrideMastodonController: MastodonController?
var mastodonController: MastodonController? { overrideMastodonController ?? navigationDelegate?.apiController }
private var htmlConverter = HTMLConverter()
var defaultFont: UIFont {
_read { yield htmlConverter.font }
_modify { yield &htmlConverter.font }
}
var defaultColor: UIColor {
_read { yield htmlConverter.color }
_modify { yield &htmlConverter.color }
}
var paragraphStyle: NSParagraphStyle {
_read { yield htmlConverter.paragraphStyle }
_modify { yield &htmlConverter.paragraphStyle }
}
private(set) var hasEmojis = false
var emojiIdentifier: String?
var emojiRequests: [ImageCache.Request] = []
var emojiFont: UIFont { defaultFont }
var emojiTextColor: UIColor { defaultColor }
// The link range currently being previewed
private var currentPreviewedLinkRange: NSRange?
// The preview created in the previewForHighlighting method, so that we can use the same one in previewForDismissing.
private weak var currentTargetedPreview: UITargetedPreview?
override init(frame: CGRect, textContainer: NSTextContainer?) {
super.init(frame: frame, textContainer: textContainer)
commonInit()
}
required init?(coder: NSCoder) {
super.init(coder: coder)
commonInit()
}
private func commonInit() {
delegate = self
// Disable layer masking, otherwise the context menu opening animation
// may be clipped if it's at an edge of the text view
layer.masksToBounds = false
addInteraction(UIContextMenuInteraction(delegate: self))
textDragInteraction?.isEnabled = false
textContainerInset = .zero
textContainer.lineFragmentPadding = 0
// the text view's builtin link interaction code is tied to isSelectable, so we need to use our own tap recognizer
let recognizer = UITapGestureRecognizer(target: self, action: #selector(textTapped(_:)))
addGestureRecognizer(recognizer)
}
// MARK: - Emojis
func setEmojis(_ emojis: [Emoji], identifier: String?) {
replaceEmojis(in: attributedText!, emojis: emojis, identifier: identifier) { attributedString, didReplaceEmojis in
guard didReplaceEmojis else {
return
}
self.attributedText = attributedString
self.setNeedsLayout()
self.setNeedsDisplay()
}
}
// MARK: - HTML Parsing
func setTextFromHtml(_ html: String) {
self.attributedText = htmlConverter.convert(html)
}
// MARK: - Interaction
// only accept touches that are over a link
override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
if getLinkAtPoint(point) != nil || isSelectable {
return super.hitTest(point, with: event)
} else {
return nil
}
}
@objc func textTapped(_ recognizer: UITapGestureRecognizer) {
// if there currently is a selection, deselct it on single-tap
if selectedRange.length > 0 {
// location doesn't matter since we are non-editable and the cursor isn't visible
selectedRange = NSRange(location: 0, length: 0)
}
let location = recognizer.location(in: self)
if let (link, range) = getLinkAtPoint(location),
link.scheme != dataDetectorsScheme {
let text = (self.text as NSString).substring(with: range)
handleLinkTapped(url: link, text: text)
}
}
func getLinkAtPoint(_ point: CGPoint) -> (URL, NSRange)? {
let locationInTextContainer = CGPoint(x: point.x - textContainerInset.left, y: point.y - textContainerInset.top)
if #available(iOS 16.0, *),
let textLayoutManager {
guard let fragment = textLayoutManager.textLayoutFragment(for: locationInTextContainer) else {
return nil
}
let pointInLayoutFragment = CGPoint(x: locationInTextContainer.x - fragment.layoutFragmentFrame.minX, y: locationInTextContainer.y - fragment.layoutFragmentFrame.minY)
guard let lineFragment = fragment.textLineFragments.first(where: { lineFragment in
lineFragment.typographicBounds.contains(pointInLayoutFragment)
}) else {
return nil
}
let pointInLineFragment = CGPoint(x: pointInLayoutFragment.x - lineFragment.typographicBounds.minX, y: pointInLayoutFragment.y - lineFragment.typographicBounds.minY)
let charIndex = lineFragment.characterIndex(for: pointInLineFragment)
var range = NSRange()
// sometimes characterIndex(for:) returns NSNotFound even for points that are in the line fragment's typographic bounds (see #183), so we check just in case
guard charIndex != NSNotFound,
let link = lineFragment.attributedString.attribute(.link, at: charIndex, longestEffectiveRange: &range, in: lineFragment.attributedString.fullRange) as? URL else {
return nil
}
// lineFragment.attributedString is the NSTextLayoutFragment's string, and so range is in its index space
// but we need to return a range in our whole attributedString's space, so convert it
let textLayoutFragmentStart = textLayoutManager.offset(from: textLayoutManager.documentRange.location, to: fragment.rangeInElement.location)
let rangeInSelf = NSRange(location: range.location + textLayoutFragmentStart, length: range.length)
return (link, rangeInSelf)
} else {
var partialFraction: CGFloat = 0
let characterIndex = layoutManager.characterIndex(for: locationInTextContainer, in: textContainer, fractionOfDistanceBetweenInsertionPoints: &partialFraction)
guard characterIndex < textStorage.length && partialFraction < 1 else {
return nil
}
var range = NSRange()
guard let link = textStorage.attribute(.link, at: characterIndex, longestEffectiveRange: &range, in: textStorage.fullRange) as? URL else {
return nil
}
return (link, range)
}
}
func handleLinkTapped(url: URL, text: String) {
if let mention = getMention(for: url, text: text) {
navigationDelegate?.selected(mention: mention)
} else if let tag = getHashtag(for: url, text: text) {
navigationDelegate?.selected(tag: tag)
} else {
navigationDelegate?.selected(url: url)
}
}
// MARK: - Navigation
func getViewController(forLink url: URL, inRange range: NSRange) -> UIViewController? {
let text = (self.text as NSString).substring(with: range)
if let mention = getMention(for: url, text: text) {
return ProfileViewController(accountID: mention.id, mastodonController: mastodonController!)
} else if let tag = getHashtag(for: url, text: text) {
return HashtagTimelineViewController(for: tag, mastodonController: mastodonController!)
} else if url.scheme == "https" || url.scheme == "http" {
return SFSafariViewController(url: url)
} else {
return nil
}
}
open func getMention(for url: URL, text: String) -> Mention? {
return nil
}
open func getHashtag(for url: URL, text: String) -> Hashtag? {
if text.starts(with: "#") {
let tag = String(text.dropFirst())
return Hashtag(name: tag, url: url)
} else {
return nil
}
}
}
extension ContentTextView: UITextViewDelegate {
func textView(_ textView: UITextView, shouldInteractWith URL: URL, in characterRange: NSRange, interaction: UITextItemInteraction) -> Bool {
// the builtin data detectors use the x-apple-data-detectors scheme, and we allow the text view to handle those itself
if URL.scheme == dataDetectorsScheme {
return true
} else {
// otherwise, regular taps are handled by the gesture recognizer, but the accessibility interaction to select links with the rotor goes through here
// and this seems to be the only way of overriding what it does
handleLinkTapped(url: URL, text: (text as NSString).substring(with: characterRange))
return false
}
}
}
extension ContentTextView: MenuActionProvider {
var toastableViewController: ToastableViewController? {
// todo: pass this down through the text view
nil
}
}
extension ContentTextView: UIContextMenuInteractionDelegate {
func contextMenuInteraction(_ interaction: UIContextMenuInteraction, configurationForMenuAtLocation location: CGPoint) -> UIContextMenuConfiguration? {
if let (link, range) = getLinkAtPoint(location) {
// Store the previewed link range for use in the previewForHighlighting method
currentPreviewedLinkRange = range
let preview: UIContextMenuContentPreviewProvider = {
self.getViewController(forLink: link, inRange: range)
}
let actions: UIContextMenuActionProvider = { (_) in
let text = (self.text as NSString).substring(with: range)
let actions: [UIMenuElement]
if let mention = self.getMention(for: link, text: text) {
actions = self.actionsForProfile(accountID: mention.id, source: .view(self))
} else if let tag = self.getHashtag(for: link, text: text) {
actions = self.actionsForHashtag(tag, source: .view(self))
} else {
actions = self.actionsForURL(link, source: .view(self))
}
return UIMenu(title: "", image: nil, identifier: nil, options: [], children: actions)
}
return UIContextMenuConfiguration(identifier: nil, previewProvider: preview, actionProvider: actions)
} else {
currentPreviewedLinkRange = nil
return nil
}
}
func contextMenuInteraction(_ interaction: UIContextMenuInteraction, previewForHighlightingMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
// If there isn't a link range, use the default system-generated preview.
guard let range = currentPreviewedLinkRange else {
return nil
}
currentPreviewedLinkRange = nil
// Determine the line rects that the link takes up in the coordinate space of this view.
var rects = [CGRect]()
if #available(iOS 16.0, *),
let textLayoutManager,
let contentManager = textLayoutManager.textContentManager {
// convert from NSRange to NSTextRange
// i have no idea under what circumstances any of these calls could fail
guard let startLoc = contentManager.location(contentManager.documentRange.location, offsetBy: range.location),
let endLoc = contentManager.location(startLoc, offsetBy: range.length),
let textRange = NSTextRange(location: startLoc, end: endLoc) else {
return nil
}
// .standard because i have no idea what the difference is
textLayoutManager.enumerateTextSegments(in: textRange, type: .standard, options: .rangeNotRequired) { range, rect, float, textContainer in
rects.append(rect)
return true
}
} else {
layoutManager.enumerateEnclosingRects(forGlyphRange: range, withinSelectedGlyphRange: NSRange(location: NSNotFound, length: 0), in: textContainer) { (rect, stop) in
rects.append(rect)
}
}
// Try to create a snapshot view of this view to disply as the preview.
// If a snapshot view cannot be created, we bail and use the system-provided preview.
guard let snapshot = self.snapshotView(afterScreenUpdates: false) else {
return nil
}
// Mask the snapshot layer to only show the text of the link, and nothing else.
// By default, the system-applied mask is too wide and other content may seep in.
let path = UIBezierPath(wrappingAround: rects)
let maskLayer = CAShapeLayer()
maskLayer.path = path.cgPath
snapshot.layer.mask = maskLayer
// The preview parameters describe how the preview view is shown inside the preview.
let parameters = UIPreviewParameters(textLineRects: rects as [NSValue])
// Calculate the smallest rect enclosing all of the text line rects, in the coordinate space of this view.
var minX: CGFloat = .greatestFiniteMagnitude, maxX: CGFloat = -.greatestFiniteMagnitude, minY: CGFloat = .greatestFiniteMagnitude, maxY: CGFloat = -.greatestFiniteMagnitude
for rect in rects {
minX = min(rect.minX, minX)
maxX = max(rect.maxX, maxX)
minY = min(rect.minY, minY)
maxY = max(rect.maxY, maxY)
}
// The center point of the the minimum enclosing rect in our coordinate space is the point where the
// center of the preview should be, since that's also in this view's coordinate space.
let rectsCenter = CGPoint(x: (minX + maxX) / 2, y: (minY + maxY) / 2)
// The preview target describes how the preview is positioned.
let target = UIPreviewTarget(container: self, center: rectsCenter)
// Create a dummy containerview for the snapshot view, since using a view with a CALayer mask and UIPreviewParameters(textLineRects:)
// causes the mask to be ignored. See FB7832297
let snapshotContainer = UIView(frame: snapshot.bounds)
snapshotContainer.backgroundColor = .systemBackground
snapshotContainer.addSubview(snapshot)
let preview = UITargetedPreview(view: snapshotContainer, parameters: parameters, target: target)
currentTargetedPreview = preview
return preview
}
func contextMenuInteraction(_ interaction: UIContextMenuInteraction, previewForDismissingMenuWithConfiguration configuration: UIContextMenuConfiguration) -> UITargetedPreview? {
// Use the same preview for dismissing as was used for highlighting, so that the link animates back to the original position.
return currentTargetedPreview
}
func contextMenuInteraction(_ interaction: UIContextMenuInteraction, willPerformPreviewActionForMenuWith configuration: UIContextMenuConfiguration, animator: UIContextMenuInteractionCommitAnimating) {
if let viewController = animator.previewViewController {
animator.preferredCommitStyle = .pop
animator.addCompletion {
self.navigationDelegate?.show(viewController)
}
}
}
}