fix mini call view (remote video view) rotation and dragging issue

Session/Calls/CallVC.swift

@@ -23,8 +23,10 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
     private lazy var localVideoView: LocalVideoView = {
         let result = LocalVideoView()
         result.isHidden = !call.isVideoEnabled
-        result.set(.width, to: 80)
-        result.set(.height, to: 173)
+        result.layer.cornerRadius = 10
+        result.layer.masksToBounds = true
+        result.set(.width, to: LocalVideoView.width)
+        result.set(.height, to: LocalVideoView.height)
         result.makeViewDraggable()
         return result
     }()
@@ -325,6 +327,7 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
         if (call.isVideoEnabled && shouldRestartCamera) { cameraManager.start() }
         shouldRestartCamera = true
         addLocalVideoView()
+        remoteVideoView.alpha = call.isRemoteVideoEnabled ? 1 : 0
     }
     
     override func viewWillDisappear(_ animated: Bool) {

Session/Calls/Views & Modals/CallVideoView.swift

@@ -67,6 +67,9 @@ class RemoteVideoView: RTCMTLVideoView {
 
 class LocalVideoView: RTCMTLVideoView {
     
+    static let width: CGFloat = 80
+    static let height: CGFloat = 173
+    
     override func renderFrame(_ frame: RTCVideoFrame?) {
         super.renderFrame(frame)
         DispatchMainThreadSafe {

Session/Calls/Views & Modals/MiniCallView.swift

@@ -1,12 +1,23 @@
 import UIKit
 import WebRTC
 
-final class MiniCallView: UIView {
+final class MiniCallView: UIView, RTCVideoViewDelegate {
     var callVC: CallVC
     
-    private lazy var remoteVideoView: RemoteVideoView = {
-        let result = RemoteVideoView()
-        result.alpha = 0
+    // MARK: UI
+    private static let defaultSize: CGFloat = 100
+    
+    private var width: NSLayoutConstraint?
+    private var height: NSLayoutConstraint?
+    private var left: NSLayoutConstraint?
+    private var right: NSLayoutConstraint?
+    private var top: NSLayoutConstraint?
+    private var bottom: NSLayoutConstraint?
+    
+    private lazy var remoteVideoView: RTCMTLVideoView = {
+        let result = RTCMTLVideoView()
+        result.delegate = self
+        result.alpha = self.callVC.call.isRemoteVideoEnabled ? 1 : 0
         result.videoContentMode = .scaleAspectFit
         result.backgroundColor = .black
         return result
@@ -22,6 +33,17 @@ final class MiniCallView: UIView {
         setUpViewHierarchy()
         setUpGestureRecognizers()
         MiniCallView.current = self
+        self.callVC.call.remoteVideoStateDidChange = { isEnabled in
+            DispatchQueue.main.async {
+                UIView.animate(withDuration: 0.25) {
+                    self.remoteVideoView.alpha = isEnabled ? 1 : 0
+                    if !isEnabled {
+                        self.width?.constant = MiniCallView.defaultSize
+                        self.height?.constant = MiniCallView.defaultSize
+                    }
+                }
+            }
+        }
     }
     
     override init(frame: CGRect) {
@@ -33,8 +55,8 @@ final class MiniCallView: UIView {
     }
     
     private func setUpViewHierarchy() {
-        self.set(.width, to: 100)
-        self.set(.height, to: 100)
+        self.width = self.set(.width, to: MiniCallView.defaultSize)
+        self.height = self.set(.height, to: MiniCallView.defaultSize)
         self.layer.cornerRadius = 10
         self.layer.masksToBounds = true
         // Background
@@ -80,9 +102,13 @@ final class MiniCallView: UIView {
         self.alpha = 0.0
         let window = CurrentAppContext().mainWindow!
         window.addSubview(self)
-        self.autoPinEdge(toSuperviewEdge: .right)
+        left = self.autoPinEdge(toSuperviewEdge: .left)
+        left?.isActive = false
+        right = self.autoPinEdge(toSuperviewEdge: .right)
         let topMargin = UIApplication.shared.keyWindow!.safeAreaInsets.top + Values.veryLargeSpacing
-        self.autoPinEdge(toSuperviewEdge: .top, withInset: topMargin)
+        top = self.autoPinEdge(toSuperviewEdge: .top, withInset: topMargin)
+        bottom = self.autoPinEdge(toSuperviewEdge: .bottom)
+        bottom?.isActive = false
         UIView.animate(withDuration: 0.5, delay: 0, options: [], animations: {
             self.alpha = 1.0
         }, completion: nil)
@@ -93,9 +119,42 @@ final class MiniCallView: UIView {
             self.alpha = 0.0
         }, completion: { _ in
             self.callVC.call.removeRemoteVideoRenderer(self.remoteVideoView)
+            self.callVC.setupStateChangeCallbacks()
             MiniCallView.current = nil
             self.removeFromSuperview()
         })
     }
+    
+    // MARK: RTCVideoViewDelegate
+    func videoView(_ videoView: RTCVideoRenderer, didChangeVideoSize size: CGSize) {
+        let newSize = CGSize(width: min(160.0, 160.0 * size.width / size.height), height: min(160.0, 160.0 * size.height / size.width))
+        persistCurrentPosition(newSize: newSize)
+        self.width?.constant = newSize.width
+        self.height?.constant = newSize.height
+    }
+    
+    func persistCurrentPosition(newSize: CGSize) {
+        let currentCenter = self.center
+        
+        if currentCenter.x < self.superview!.width() / 2 {
+            left?.isActive = true
+            right?.isActive = false
+        } else {
+            left?.isActive = false
+            right?.isActive = true
+        }
+        
+        let willTouchTop = currentCenter.y < newSize.height / 2
+        let willTouchBottom = currentCenter.y + newSize.height / 2 >= self.superview!.height()
+        if willTouchBottom {
+            top?.isActive = false
+            bottom?.isActive = true
+        } else {
+            let constant = willTouchTop ? 0 : currentCenter.y - newSize.height / 2
+            top?.constant = constant
+            top?.isActive = true
+            bottom?.isActive = false
+        }
+    }
 
 }

Session/Utilities/UIView+Draggable.swift

@@ -12,26 +12,25 @@ extension UIView {
         if let draggedView = gesture.view {
             draggedView.center = location
             if gesture.state == .ended {
-                let sideMargin = 40 + Values.verySmallSpacing
                 if draggedView.frame.midX >= self.superview!.layer.frame.width / 2 {
                     UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
-                        draggedView.center.x = self.superview!.layer.frame.width - sideMargin
+                        draggedView.center.x = self.superview!.layer.frame.width - draggedView.width() / 2
                     }, completion: nil)
                 }else{
                     UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
-                        draggedView.center.x = sideMargin
+                        draggedView.center.x = draggedView.width() / 2
                     }, completion: nil)
                 }
                 let topMargin = UIApplication.shared.keyWindow!.safeAreaInsets.top + Values.veryLargeSpacing
                 if draggedView.frame.minY <= topMargin {
                     UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
-                        draggedView.center.y = topMargin + draggedView.frame.size.height / 2
+                        draggedView.center.y = topMargin + draggedView.height() / 2
                     }, completion: nil)
                 }
                 let bottomMargin = UIApplication.shared.keyWindow!.safeAreaInsets.bottom
                 if draggedView.frame.maxY >= self.superview!.layer.frame.height {
                     UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
-                        draggedView.center.y = self.layer.frame.height - draggedView.frame.size.height / 2 - bottomMargin
+                        draggedView.center.y = self.layer.frame.height - draggedView.height() / 2 - bottomMargin
                     }, completion: nil)
                 }
             }