Add snapshot pill for incoming mentions

Riot/Modules/Pills/PillSnapshoter.swift

@@ -0,0 +1,87 @@
+// 
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+
+// TODO: replace this with directly creating NSAttributedString with both link and attachment (removes weird interaction between two objects here)
+@objcMembers class PillTextAttachment: NSTextAttachment {
+    convenience init(withSession session: MXSession, url: NSURL, andRoomMember roomMember: MXRoomMember) {
+        self.init()
+        
+        let image = PillSnapshoter.snapshot(withSession: session, andRoomMember: roomMember)
+        self.image = image
+        // FIXME: handle vertical offset better
+        self.bounds = CGRect(x: 0.0, y: -5.0, width: image.size.width * 0.3, height: image.size.height * 0.3)
+    }
+}
+
+@objcMembers class PillSnapshoter: NSObject {
+    static func mentionPill(withSession session: MXSession, url: NSURL, andRoomMember roomMember: MXRoomMember) -> NSAttributedString {
+        let attachment = PillTextAttachment(withSession: session, url: url, andRoomMember: roomMember)
+        let string = NSAttributedString(attachment: attachment)
+        let mutable = NSMutableAttributedString(attributedString: string)
+        mutable.addAttribute(.link, value: url, range: .init(location: 0, length: mutable.length))
+        return mutable
+    }
+    
+    static func snapshot(withSession session: MXSession, andRoomMember roomMember: MXRoomMember) -> UIImage {
+        let view = snapshotView(withSession: session, andRoomMember: roomMember)
+        let rect: CGRect = view.frame
+
+        UIGraphicsBeginImageContext(rect.size)
+        let context: CGContext = UIGraphicsGetCurrentContext()!
+        view.layer.render(in: context)
+        let img = UIGraphicsGetImageFromCurrentImageContext()
+        UIGraphicsEndImageContext()
+        
+        return img!
+    }
+    
+    // TODO: Improve how image scale is handled
+    // TODO: Implement a solution with image cache to increase performance
+    private static func snapshotView(withSession session: MXSession, andRoomMember roomMember: MXRoomMember) -> UIView {
+        let label = UILabel(frame: .zero)
+        label.text = roomMember.displayname
+        label.font = ThemeService.shared().theme.fonts.body.withSize(ThemeService.shared().theme.fonts.body.pointSize * 2.0)
+        label.textColor = ThemeService.shared().theme.textPrimaryColor
+        let labelSize = label.sizeThatFits(CGSize(width: CGFloat.greatestFiniteMagnitude,
+                                                  height: CGFloat.greatestFiniteMagnitude))
+        label.frame = CGRect(x: 52 + 16, y: 0, width: labelSize.width, height: 60)
+        
+        let view = UIView(frame: CGRect(x: 0, y: 0, width: labelSize.width + 16 + 52 + 16, height: 60))
+        
+        // FIXME: handle avatar not being in cache at snapshot time
+        let imageView = MXKImageView(frame: CGRect(x: 8, y: 4, width: 60, height: 60))
+        imageView.setImageURI(roomMember.avatarUrl,
+                              withType: nil,
+                              andImageOrientation: .up,
+                              toFitViewSize: imageView.frame.size,
+                              with: MXThumbnailingMethodCrop,
+                              previewImage: Asset.Images.userIcon.image,
+                              mediaManager: session.mediaManager)
+        imageView.clipsToBounds = true
+        imageView.frame = CGRect(x: 8, y: 4, width: 52, height: 52)
+        imageView.layer.cornerRadius = 26.0
+        view.addSubview(imageView)
+
+        view.addSubview(label)
+        
+        view.backgroundColor = ThemeService.shared().theme.secondaryCircleButtonBackgroundColor
+        view.layer.cornerRadius = 30
+        
+        return view
+    }
+}

Riot/Modules/Pills/StringPillsUtils.swift

@@ -0,0 +1,66 @@
+// 
+// Copyright 2022 New Vector Ltd
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+//
+
+import Foundation
+
+@objcMembers
+class StringPillsUtils: NSObject {
+    // MARK: - Private Constants
+    private enum Constants {
+        // TODO: replace this with a solution handling any kind of custom permalinks.
+        static let matrixToURL: String = "https://matrix.to/#/"
+    }
+    
+    // MARK: - Internal Methods
+    static func insertPills(in attributedString: NSAttributedString,
+                            withSession session: MXSession,
+                            andRoomState roomState: MXRoomState) -> NSAttributedString {
+        // TODO: Improve algorithm & cleanup this method
+        let newAttr = NSMutableAttributedString(attributedString: attributedString)
+        var lastIndex: Int = 0
+        
+        while lastIndex < newAttr.length {
+            var url: NSURL?
+            let linkRange = newAttr.rangeOfLink(at: UInt(lastIndex), url: &url)
+
+            guard let url = url,
+                  // FIXME: remove this check if only encrypted message replacer sets non-URL objects in NSLink attributes
+                  url.isKind(of: NSURL.self),
+                  let absoluteString = url.absoluteString,
+                  absoluteString.starts(with: Constants.matrixToURL)
+            else {
+                lastIndex += 1
+                continue
+            }
+            
+            let userId = String(absoluteString.dropFirst(Constants.matrixToURL.count))
+            
+            if linkRange.length > 0 {
+                guard let roomMember = roomState.members.member(withUserId: userId) else {
+                    lastIndex += linkRange.length
+                    continue
+                }
+                let attachmentString = PillSnapshoter.mentionPill(withSession: session, url: url, andRoomMember: roomMember)
+                newAttr.replaceCharacters(in: linkRange, with: attachmentString)
+                lastIndex += attachmentString.length
+            } else {
+                lastIndex += 1
+            }
+        }
+        
+        return newAttr
+    }
+}