Use the SDK Client to check whether a homeserver is compatible (#5664)

* Use the SDK `Client` to check whether a HS is compatible

* Remove usage of unused `WellKnown`, keep `ElementWellKnown`

* Make `HomeServerLoginCompatibilityChecker.check` return `true/false` values to distinguish non-valid homeservers from a failed check

* Use `inMemoryStore` and `serverNameOrHomeserverUrl`

* Do some cleanup of `isValid` and `isWellknownValid`

* Make the debounce for starting the search a bit higher, as checking for the homeservers seems more resource-intensive now

libraries/matrix/impl/src/main/kotlin/io/element/android/libraries/matrix/impl/auth/RustHomeServerLoginCompatibilityChecker.kt

@@ -0,0 +1,36 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.impl.auth
+
+import dev.zacsweers.metro.AppScope
+import dev.zacsweers.metro.ContributesBinding
+import dev.zacsweers.metro.Inject
+import io.element.android.libraries.core.extensions.runCatchingExceptions
+import io.element.android.libraries.matrix.api.auth.HomeServerLoginCompatibilityChecker
+import io.element.android.libraries.matrix.impl.ClientBuilderProvider
+import timber.log.Timber
+
+@ContributesBinding(AppScope::class)
+@Inject
+class RustHomeServerLoginCompatibilityChecker(
+    private val clientBuilderProvider: ClientBuilderProvider,
+) : HomeServerLoginCompatibilityChecker {
+    override suspend fun check(url: String): Result<Boolean> = runCatchingExceptions {
+        clientBuilderProvider.provide()
+            .inMemoryStore()
+            .serverNameOrHomeserverUrl(url)
+            .build()
+            .use {
+                it.homeserverLoginDetails()
+            }
+            .use {
+                Timber.d("Homeserver $url | OIDC: ${it.supportsOidcLogin()} | Password: ${it.supportsPasswordLogin()} | SSO: ${it.supportsSsoLogin()}")
+                it.supportsOidcLogin() || it.supportsPasswordLogin()
+            }
+    }
+}

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/auth/RustHomeserverLoginCompatibilityCheckerTest.kt

@@ -0,0 +1,54 @@
+/*
+ * Copyright 2025 New Vector Ltd.
+ *
+ * SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+ * Please see LICENSE files in the repository root for full details.
+ */
+
+package io.element.android.libraries.matrix.impl.auth
+
+import com.google.common.truth.Truth.assertThat
+import io.element.android.libraries.matrix.impl.FakeClientBuilderProvider
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiClient
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiClientBuilder
+import io.element.android.libraries.matrix.impl.fixtures.fakes.FakeFfiHomeserverLoginDetails
+import kotlinx.coroutines.test.runTest
+import org.junit.Ignore
+import org.junit.Test
+
+@Ignore("JNA direct mapping has broken unit tests with FFI fakes")
+class RustHomeserverLoginCompatibilityCheckerTest {
+    @Test
+    fun `check - is valid if it supports OIDC login`() = runTest {
+        val sut = createChecker { FakeFfiHomeserverLoginDetails(supportsOidcLogin = true) }
+        assertThat(sut.check("https://matrix.host.org").getOrNull()).isTrue()
+    }
+
+    @Test
+    fun `check - is valid if it supports password login`() = runTest {
+        val sut = createChecker { FakeFfiHomeserverLoginDetails(supportsPasswordLogin = true) }
+        assertThat(sut.check("https://matrix.host.org").getOrNull()).isTrue()
+    }
+
+    @Test
+    fun `check - is not valid if it only supports SSO login`() = runTest {
+        val sut = createChecker { FakeFfiHomeserverLoginDetails(supportsSsoLogin = true) }
+        assertThat(sut.check("https://matrix.host.org").getOrNull()).isFalse()
+    }
+
+    @Test
+    fun `check - is not valid if fetching the data fails`() = runTest {
+        val sut = createChecker { error("Unexpected error!") }
+        assertThat(sut.check("https://matrix.host.org").isFailure).isTrue()
+    }
+
+    private fun createChecker(
+        result: () -> FakeFfiHomeserverLoginDetails,
+    ) = RustHomeServerLoginCompatibilityChecker(
+        clientBuilderProvider = FakeClientBuilderProvider {
+            FakeFfiClientBuilder {
+                FakeFfiClient(homeserverLoginDetailsResult = result)
+            }
+        }
+    )
+}

libraries/matrix/impl/src/test/kotlin/io/element/android/libraries/matrix/impl/fixtures/fakes/FakeFfiHomeserverLoginDetails.kt

@@ -12,10 +12,12 @@ import org.matrix.rustcomponents.sdk.NoHandle
 
 class FakeFfiHomeserverLoginDetails(
     private val url: String = "https://example.org",
-    private val supportsPasswordLogin: Boolean = true,
-    private val supportsOidcLogin: Boolean = false
+    private val supportsPasswordLogin: Boolean = false,
+    private val supportsOidcLogin: Boolean = false,
+    private val supportsSsoLogin: Boolean = false,
 ) : HomeserverLoginDetails(NoHandle) {
     override fun url(): String = url
     override fun supportsOidcLogin(): Boolean = supportsOidcLogin
     override fun supportsPasswordLogin(): Boolean = supportsPasswordLogin
+    override fun supportsSsoLogin(): Boolean = supportsSsoLogin
 }