Introduce CallService

Riot/Managers/Call/Operations/CallBarPresentOperation.swift

@@ -0,0 +1,40 @@
+// 
+// Copyright 2020 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
+
+class CallBarPresentOperation: AsyncOperation {
+    
+    private var service: CallService
+    private var callVC: CallViewController
+    private var completion: (() -> Void)?
+    
+    init(service: CallService,
+         callVC: CallViewController,
+         completion: (() -> Void)? = nil) {
+        self.service = service
+        self.callVC = callVC
+        self.completion = completion
+    }
+    
+    override func main() {
+        service.delegate?.callService(service, presentCallBarFor: callVC, completion: {
+            self.finish()
+            self.completion?()
+        })
+    }
+    
+}