Create enum as per the spec and use default values when applicable

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/call/CallAnswerContent.kt

@@ -35,7 +35,7 @@ data class CallAnswerContent(
         /**
          * Required. The version of the VoIP specification this messages adheres to. This specification is version 0.
          */
-        @Json(name = "version") val version: Int
+        @Json(name = "version") val version: Int = 0
 ) {
 
     @JsonClass(generateAdapter = true)
@@ -43,7 +43,7 @@ data class CallAnswerContent(
             /**
              * Required. The type of session description. Must be 'answer'.
              */
-            @Json(name = "type") val type: String,
+            @Json(name = "type") val type: SdpType = SdpType.ANSWER,
             /**
              * Required. The SDP text of the session description.
              */

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/call/CallCandidatesContent.kt

@@ -36,7 +36,7 @@ data class CallCandidatesContent(
         /**
          * Required. The version of the VoIP specification this messages adheres to. This specification is version 0.
          */
-        @Json(name = "version") val version: Int
+        @Json(name = "version") val version: Int = 0
 ) {
 
     @JsonClass(generateAdapter = true)

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/call/CallHangupContent.kt

@@ -32,11 +32,19 @@ data class CallHangupContent(
         /**
          * Required. The version of the VoIP specification this message adheres to. This specification is version 0.
          */
-        @Json(name = "version") val version: Int,
+        @Json(name = "version") val version: Int = 0,
         /**
          * Optional error reason for the hangup. This should not be provided when the user naturally ends or rejects the call.
          * When there was an error in the call negotiation, this should be `ice_failed` for when ICE negotiation fails
          * or `invite_timeout` for when the other party did not answer in time. One of: ["ice_failed", "invite_timeout"]
          */
-        @Json(name = "reason") val reason: String?
-)
+        @Json(name = "reason") val reason: Reason? = null
+) {
+    enum class Reason {
+        @Json(name = "ice_failed")
+        ICE_FAILED,
+
+        @Json(name = "invite_timeout")
+        INVITE_TIMEOUT
+    }
+}

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/call/CallInviteContent.kt

@@ -31,24 +31,24 @@ data class CallInviteContent(
         /**
          * Required. The session description object
          */
-        @Json(name = "version") val version: Int?,
+        @Json(name = "offer") val offer: Offer?,
         /**
          * Required. The version of the VoIP specification this message adheres to. This specification is version 0.
          */
-        @Json(name = "lifetime") val lifetime: Int?,
+        @Json(name = "version") val version: Int? = 0,
         /**
          * Required. The time in milliseconds that the invite is valid for.
          * Once the invite age exceeds this value, clients should discard it.
          * They should also no longer show the call as awaiting an answer in the UI.
          */
-        @Json(name = "offer") val offer: Offer?
+        @Json(name = "lifetime") val lifetime: Int?
 ) {
     @JsonClass(generateAdapter = true)
     data class Offer(
             /**
              * Required. The type of session description. Must be 'offer'.
              */
-            @Json(name = "type") val type: String?,
+            @Json(name = "type") val type: SdpType? = SdpType.OFFER,
             /**
              * Required. The SDP text of the session description.
              */

matrix-sdk-android/src/main/java/im/vector/matrix/android/api/session/room/model/call/SdpType.kt

@@ -0,0 +1,27 @@
+/*
+ * Copyright (c) 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.
+ */
+
+package im.vector.matrix.android.api.session.room.model.call
+
+import com.squareup.moshi.Json
+
+enum class SdpType {
+    @Json(name = "offer")
+    OFFER,
+
+    @Json(name = "answer")
+    ANSWER
+}

matrix-sdk-android/src/main/java/im/vector/matrix/android/internal/session/call/DefaultCallService.kt

@@ -61,12 +61,8 @@ internal class DefaultCallService @Inject constructor(
     override fun sendOfferSdp(callId: String, roomId: String, sdp: SessionDescription, callback: MatrixCallback<String>) {
         val eventContent = CallInviteContent(
                 callId = callId,
-                version = 0,
                 lifetime = CALL_TIMEOUT_MS,
-                offer = CallInviteContent.Offer(
-                        type = sdp.type.canonicalForm(),
-                        sdp = sdp.description
-                )
+                offer = CallInviteContent.Offer(sdp = sdp.description)
         )
 
         createEventAndLocalEcho(type = EventType.CALL_INVITE, roomId = roomId, content = eventContent.toContent()).let { event ->
@@ -83,11 +79,7 @@ internal class DefaultCallService @Inject constructor(
     override fun sendAnswerSdp(callId: String, roomId: String, sdp: SessionDescription, callback: MatrixCallback<String>) {
         val eventContent = CallAnswerContent(
                 callId = callId,
-                version = 0,
-                answer = CallAnswerContent.Answer(
-                        type = sdp.type.canonicalForm(),
-                        sdp = sdp.description
-                )
+                answer = CallAnswerContent.Answer(sdp = sdp.description)
         )
 
         createEventAndLocalEcho(type = EventType.CALL_INVITE, roomId = roomId, content = eventContent.toContent()).let { event ->
@@ -104,7 +96,6 @@ internal class DefaultCallService @Inject constructor(
     override fun sendLocalIceCandidates(callId: String, roomId: String, candidates: List<IceCandidate>) {
         val eventContent = CallCandidatesContent(
                 callId = callId,
-                version = 0,
                 candidates = candidates.map {
                     CallCandidatesContent.Candidate(
                             sdpMid = it.sdpMid,
@@ -128,11 +119,7 @@ internal class DefaultCallService @Inject constructor(
     }
 
     override fun sendHangup(callId: String, roomId: String) {
-        val eventContent = CallHangupContent(
-                callId = callId,
-                version = 0,
-                reason = null
-        )
+        val eventContent = CallHangupContent(callId = callId)
         createEventAndLocalEcho(type = EventType.CALL_HANGUP, roomId = roomId, content = eventContent.toContent()).let { event ->
             roomEventSender.sendEvent(event)
         }
@@ -146,7 +133,7 @@ internal class DefaultCallService @Inject constructor(
         callListeners.remove(listener)
     }
 
-    fun onCallEvent(event: Event) {
+    internal fun onCallEvent(event: Event) {
         when (event.getClearType()) {
             EventType.CALL_ANSWER -> {
                 event.getClearContent().toModel<CallAnswerContent>()?.let {