Add OIDC support

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/AuthenticationException.kt

@@ -22,4 +22,5 @@ sealed class AuthenticationException(message: String) : Exception(message) {
     class SlidingSyncNotAvailable(message: String) : AuthenticationException(message)
     class SessionMissing(message: String) : AuthenticationException(message)
     class Generic(message: String) : AuthenticationException(message)
+    class OidcError(type: String, message: String) : AuthenticationException(message)
 }

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/MatrixAuthenticationService.kt

@@ -28,4 +28,23 @@ interface MatrixAuthenticationService {
     fun getHomeserverDetails(): StateFlow<MatrixHomeServerDetails?>
     suspend fun setHomeserver(homeserver: String): Result<Unit>
     suspend fun login(username: String, password: String): Result<SessionId>
+
+    /*
+     * OIDC part.
+     */
+
+    /**
+     * Get the Oidc url to display to the user.
+     */
+    suspend fun getOidcUrl(): Result<OidcDetails>
+
+    /**
+     * Cancel Oidc login sequence.
+     */
+    suspend fun cancelOidcLogin(): Result<Unit>
+
+    /**
+     * Attempt to login using the [callbackUrl] provided by the Oidc page.
+     */
+    suspend fun loginWithOidc(callbackUrl: String): Result<SessionId>
 }

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/MatrixHomeServerDetails.kt

@@ -23,5 +23,5 @@ import kotlinx.parcelize.Parcelize
 data class MatrixHomeServerDetails(
     val url: String,
     val supportsPasswordLogin: Boolean,
-    val authenticationIssuer: String?
+    val supportsOidc: Boolean,
 ): Parcelable

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/OidcConfig.kt

@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2023 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 io.element.android.libraries.matrix.api.auth
+
+object OidcConfig {
+    const val redirectUri = "io.element:/callback"
+}

libraries/matrix/api/src/main/kotlin/io/element/android/libraries/matrix/api/auth/OidcDetails.kt

@@ -0,0 +1,25 @@
+/*
+ * Copyright (c) 2023 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 io.element.android.libraries.matrix.api.auth
+
+import android.os.Parcelable
+import kotlinx.parcelize.Parcelize
+
+@Parcelize
+data class OidcDetails(
+    val url: String,
+) : Parcelable