Verification with QrCode: ensure there is a Camera to scan QrCodes.

vector/src/main/java/im/vector/riotx/core/hardware/HardwareInfo.kt

@@ -0,0 +1,46 @@
+/*
+ * 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.
+ */
+
+@file:Suppress("DEPRECATION")
+
+package im.vector.riotx.core.hardware
+
+import android.content.Context
+import android.hardware.Camera
+import android.hardware.camera2.CameraCharacteristics
+import android.hardware.camera2.CameraManager
+import android.os.Build
+import javax.inject.Inject
+
+class HardwareInfo @Inject constructor(
+        private val context: Context
+) {
+    /**
+     * Tell if the device has a back (or external) camera
+     */
+    fun hasBackCamera(): Boolean {
+        if (Build.VERSION.SDK_INT < Build.VERSION_CODES.LOLLIPOP) {
+            return Camera.getNumberOfCameras() > 0
+        }
+
+        val manager = context.getSystemService(Context.CAMERA_SERVICE) as CameraManager? ?: return Camera.getNumberOfCameras() > 0
+
+        return manager.cameraIdList.any {
+            val lensFacing = manager.getCameraCharacteristics(it).get(CameraCharacteristics.LENS_FACING)
+            lensFacing == CameraCharacteristics.LENS_FACING_BACK || lensFacing == CameraCharacteristics.LENS_FACING_EXTERNAL
+        }
+    }
+}

vector/src/main/java/im/vector/riotx/features/crypto/verification/Config.kt

@@ -1,29 +0,0 @@
-/*
- * 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.
- */
-
-package im.vector.riotx.features.crypto.verification
-
-import im.vector.matrix.android.api.session.crypto.verification.VerificationMethod
-
-val supportedVerificationMethods =
-        listOf(
-                // RiotX supports SAS verification
-                VerificationMethod.SAS,
-                // RiotX is able to show QR codes
-                VerificationMethod.QR_CODE_SHOW,
-                // RiotX is able to scan QR codes
-                VerificationMethod.QR_CODE_SCAN
-        )

vector/src/main/java/im/vector/riotx/features/crypto/verification/SupportedVerificationMethodsProvider.kt

@@ -0,0 +1,47 @@
+/*
+ * 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.
+ */
+
+package im.vector.riotx.features.crypto.verification
+
+import im.vector.matrix.android.api.session.crypto.verification.VerificationMethod
+import im.vector.riotx.core.hardware.HardwareInfo
+import timber.log.Timber
+import javax.inject.Inject
+
+class SupportedVerificationMethodsProvider @Inject constructor(
+        private val hardwareInfo: HardwareInfo
+) {
+    /**
+     * Provide the list of supported method by RiotX, with or without the QR_CODE_SCAN, depending if a back camera
+     * is available
+     */
+    fun provide(): List<VerificationMethod> {
+        return mutableListOf(
+                // RiotX supports SAS verification
+                VerificationMethod.SAS,
+                // RiotX is able to show QR codes
+                VerificationMethod.QR_CODE_SHOW)
+                .apply {
+                    if (hardwareInfo.hasBackCamera()) {
+                        // RiotX is able to scan QR codes, and a Camera is available
+                        add(VerificationMethod.QR_CODE_SCAN)
+                    } else {
+                        // This quite uncommon
+                        Timber.w("No back Camera detected")
+                    }
+                }
+    }
+}

vector/src/main/java/im/vector/riotx/features/crypto/verification/VerificationBottomSheetViewModel.kt

@@ -63,9 +63,11 @@ data class VerificationBottomSheetViewState(
         val isMe: Boolean = false
 ) : MvRxState
 
-class VerificationBottomSheetViewModel @AssistedInject constructor(@Assisted initialState: VerificationBottomSheetViewState,
-                                                                   @Assisted args: VerificationBottomSheet.VerificationArgs,
-                                                                   private val session: Session)
+class VerificationBottomSheetViewModel @AssistedInject constructor(
+        @Assisted initialState: VerificationBottomSheetViewState,
+        @Assisted args: VerificationBottomSheet.VerificationArgs,
+        private val session: Session,
+        private val supportedVerificationMethodsProvider: SupportedVerificationMethodsProvider)
     : VectorViewModel<VerificationBottomSheetViewState, VerificationAction, VerificationBottomSheetViewEvents>(initialState),
         VerificationService.Listener {
 
@@ -116,9 +118,11 @@ class VerificationBottomSheetViewModel @AssistedInject constructor(@Assisted ini
         if (autoReady) {
             // TODO, can I be here in DM mode? in this case should test if roomID is null?
             session.cryptoService().verificationService()
-                    .readyPendingVerification(supportedVerificationMethods,
+                    .readyPendingVerification(
+                            supportedVerificationMethodsProvider.provide(),
                             pr!!.otherUserId,
-                            pr.transactionId ?: "")
+                            pr.transactionId ?: ""
+                    )
         }
     }
 
@@ -173,7 +177,7 @@ class VerificationBottomSheetViewModel @AssistedInject constructor(@Assisted ini
                                                 session
                                                         .cryptoService()
                                                         .verificationService()
-                                                        .requestKeyVerificationInDMs(supportedVerificationMethods, otherUserId, data, pendingLocalId)
+                                                        .requestKeyVerificationInDMs(supportedVerificationMethodsProvider.provide(), otherUserId, data, pendingLocalId)
                                         )
                                 )
                             }
@@ -191,7 +195,7 @@ class VerificationBottomSheetViewModel @AssistedInject constructor(@Assisted ini
                                 pendingRequest = Success(session
                                         .cryptoService()
                                         .verificationService()
-                                        .requestKeyVerificationInDMs(supportedVerificationMethods, otherUserId, roomId)
+                                        .requestKeyVerificationInDMs(supportedVerificationMethodsProvider.provide(), otherUserId, roomId)
                                 )
                         )
                     }
@@ -362,9 +366,11 @@ class VerificationBottomSheetViewModel @AssistedInject constructor(@Assisted ini
                     // auto ready in this case, as we are waiting
                     // TODO, can I be here in DM mode? in this case should test if roomID is null?
                     session.cryptoService().verificationService()
-                            .readyPendingVerification(supportedVerificationMethods,
+                            .readyPendingVerification(
+                                    supportedVerificationMethodsProvider.provide(),
                                     pr.otherUserId,
-                                    pr.transactionId ?: "")
+                                    pr.transactionId ?: ""
+                            )
                 }
 
                 // Use this one!

vector/src/main/java/im/vector/riotx/features/home/room/detail/RoomDetailViewModel.kt

@@ -65,7 +65,7 @@ import im.vector.riotx.core.resources.UserPreferencesProvider
 import im.vector.riotx.core.utils.subscribeLogError
 import im.vector.riotx.features.command.CommandParser
 import im.vector.riotx.features.command.ParsedCommand
-import im.vector.riotx.features.crypto.verification.supportedVerificationMethods
+import im.vector.riotx.features.crypto.verification.SupportedVerificationMethodsProvider
 import im.vector.riotx.features.home.room.detail.composer.rainbow.RainbowGenerator
 import im.vector.riotx.features.home.room.detail.timeline.helper.TimelineDisplayableEvents
 import im.vector.riotx.features.home.room.typing.TypingHelper
@@ -81,13 +81,15 @@ import java.io.File
 import java.util.concurrent.TimeUnit
 import java.util.concurrent.atomic.AtomicBoolean
 
-class RoomDetailViewModel @AssistedInject constructor(@Assisted initialState: RoomDetailViewState,
-                                                      userPreferencesProvider: UserPreferencesProvider,
-                                                      private val vectorPreferences: VectorPreferences,
-                                                      private val stringProvider: StringProvider,
-                                                      private val typingHelper: TypingHelper,
-                                                      private val rainbowGenerator: RainbowGenerator,
-                                                      private val session: Session
+class RoomDetailViewModel @AssistedInject constructor(
+        @Assisted initialState: RoomDetailViewState,
+        userPreferencesProvider: UserPreferencesProvider,
+        private val vectorPreferences: VectorPreferences,
+        private val stringProvider: StringProvider,
+        private val typingHelper: TypingHelper,
+        private val rainbowGenerator: RainbowGenerator,
+        private val session: Session,
+        private val supportedVerificationMethodsProvider: SupportedVerificationMethodsProvider
 ) : VectorViewModel<RoomDetailViewState, RoomDetailAction, RoomDetailViewEvents>(initialState), Timeline.Listener {
 
     private val room = session.getRoom(initialState.roomId)!!
@@ -421,7 +423,7 @@ class RoomDetailViewModel @AssistedInject constructor(@Assisted initialState: Ro
                             session
                                     .cryptoService()
                                     .verificationService()
-                                    .requestKeyVerificationInDMs(supportedVerificationMethods, slashCommandResult.userId, room.roomId)
+                                    .requestKeyVerificationInDMs(supportedVerificationMethodsProvider.provide(), slashCommandResult.userId, room.roomId)
                             _viewEvents.post(RoomDetailViewEvents.SlashCommandHandled())
                             popDraft()
                         }
@@ -828,7 +830,7 @@ class RoomDetailViewModel @AssistedInject constructor(@Assisted initialState: Ro
     private fun handleAcceptVerification(action: RoomDetailAction.AcceptVerificationRequest) {
         Timber.v("## SAS handleAcceptVerification ${action.otherUserId},  roomId:${room.roomId}, txId:${action.transactionId}")
         if (session.cryptoService().verificationService().readyPendingVerificationInDMs(
-                        supportedVerificationMethods,
+                        supportedVerificationMethodsProvider.provide(),
                         action.otherUserId,
                         room.roomId,
                         action.transactionId)) {

vector/src/main/java/im/vector/riotx/features/navigation/DefaultNavigator.kt

@@ -24,7 +24,6 @@ import androidx.core.app.ActivityOptionsCompat
 import androidx.core.app.TaskStackBuilder
 import androidx.core.view.ViewCompat
 import im.vector.matrix.android.api.session.crypto.verification.IncomingSasVerificationTransaction
-import im.vector.matrix.android.api.session.crypto.verification.VerificationMethod
 import im.vector.matrix.android.api.session.room.model.roomdirectory.PublicRoom
 import im.vector.matrix.android.api.util.MatrixItem
 import im.vector.riotx.R
@@ -35,6 +34,7 @@ import im.vector.riotx.core.utils.toast
 import im.vector.riotx.features.createdirect.CreateDirectRoomActivity
 import im.vector.riotx.features.crypto.keysbackup.settings.KeysBackupManageActivity
 import im.vector.riotx.features.crypto.keysbackup.setup.KeysBackupSetupActivity
+import im.vector.riotx.features.crypto.verification.SupportedVerificationMethodsProvider
 import im.vector.riotx.features.crypto.verification.VerificationBottomSheet
 import im.vector.riotx.features.debug.DebugMenuActivity
 import im.vector.riotx.features.home.room.detail.RoomDetailActivity
@@ -56,7 +56,8 @@ import javax.inject.Singleton
 @Singleton
 class DefaultNavigator @Inject constructor(
         private val sessionHolder: ActiveSessionHolder,
-        private val vectorPreferences: VectorPreferences
+        private val vectorPreferences: VectorPreferences,
+        private val supportedVerificationMethodsProvider: SupportedVerificationMethodsProvider
 ) : Navigator {
 
     override fun openRoom(context: Context, roomId: String, eventId: String?, buildTask: Boolean) {
@@ -85,9 +86,10 @@ class DefaultNavigator @Inject constructor(
     override fun requestSessionVerification(context: Context) {
         val session = sessionHolder.getSafeActiveSession() ?: return
         val pr = session.cryptoService().verificationService().requestKeyVerification(
-                listOf(VerificationMethod.SAS, VerificationMethod.QR_CODE_SCAN, VerificationMethod.QR_CODE_SHOW),
+                supportedVerificationMethodsProvider.provide(),
                 session.myUserId,
-                session.cryptoService().getUserDevices(session.myUserId).map { it.deviceId })
+                session.cryptoService().getUserDevices(session.myUserId).map { it.deviceId }
+        )
         if (context is VectorBaseActivity) {
             VerificationBottomSheet.withArgs(
                     roomId = null,

vector/src/main/java/im/vector/riotx/features/settings/devices/DevicesViewModel.kt

@@ -40,7 +40,7 @@ import im.vector.matrix.android.internal.crypto.model.rest.DeviceInfo
 import im.vector.matrix.android.internal.crypto.model.rest.DevicesListResponse
 import im.vector.matrix.rx.rx
 import im.vector.riotx.core.platform.VectorViewModel
-import im.vector.riotx.features.crypto.verification.supportedVerificationMethods
+import im.vector.riotx.features.crypto.verification.SupportedVerificationMethodsProvider
 
 data class DevicesViewState(
         val myDeviceId: String = "",
@@ -50,8 +50,10 @@ data class DevicesViewState(
         val request: Async<Unit> = Uninitialized
 ) : MvRxState
 
-class DevicesViewModel @AssistedInject constructor(@Assisted initialState: DevicesViewState,
-                                                   private val session: Session)
+class DevicesViewModel @AssistedInject constructor(
+        @Assisted initialState: DevicesViewState,
+        private val session: Session,
+        private val supportedVerificationMethodsProvider: SupportedVerificationMethodsProvider)
     : VectorViewModel<DevicesViewState, DevicesAction, DevicesViewEvents>(initialState), VerificationService.Listener {
 
     @AssistedInject.Factory
@@ -172,7 +174,9 @@ class DevicesViewModel @AssistedInject constructor(@Assisted initialState: Devic
     }
 
     private fun handleVerify(action: DevicesAction.VerifyMyDevice) {
-        val txID = session.cryptoService().verificationService().requestKeyVerification(supportedVerificationMethods, session.myUserId, listOf(action.deviceId))
+        val txID = session.cryptoService()
+                .verificationService()
+                .requestKeyVerification(supportedVerificationMethodsProvider.provide(), session.myUserId, listOf(action.deviceId))
         _viewEvents.post(DevicesViewEvents.ShowVerifyDevice(
                 session.myUserId,
                 txID.transactionId