select a server on tap and refuse to delete the active one

app/src/main/kotlin/com/subtracks/data/db/SourcesDao.kt

@@ -20,9 +20,6 @@ interface SourcesDao {
     @Query("SELECT * FROM sources WHERE id = :id")
     suspend fun sourceOnce(id: Long): Source?
 
-    @Query("SELECT COUNT(*) FROM sources")
-    suspend fun sourceCount(): Int
-
     @Query("SELECT id FROM sources WHERE isActive = 1 LIMIT 1")
     fun activeSourceId(): Flow<Long?>
 
@@ -32,9 +29,6 @@ interface SourcesDao {
     @Query("SELECT id FROM sources WHERE isActive = 1 LIMIT 1")
     suspend fun activeSourceIdOnce(): Long?
 
-    @Query("SELECT id FROM sources ORDER BY createdAt LIMIT 1")
-    suspend fun firstSourceId(): Long?
-
     @Insert
     suspend fun insertSource(source: Source): Long
 

app/src/main/kotlin/com/subtracks/data/repo/SourceRepository.kt

@@ -175,13 +175,8 @@ class SourceRepository(
     }
 
     suspend fun deleteSource(id: Long): Boolean {
-        val dao = db.sourcesDao()
-        if (dao.sourceCount() <= 1) return false
-        val wasActive = dao.activeSourceIdOnce() == id
-        dao.deleteSource(id)
-        if (wasActive) {
-            dao.firstSourceId()?.let { dao.setActiveSource(it) }
-        }
+        if (db.sourcesDao().activeSourceIdOnce() == id) return false
+        db.sourcesDao().deleteSource(id)
         return true
     }
 

app/src/main/kotlin/com/subtracks/ui/settings/AddSourceScreen.kt

@@ -173,7 +173,7 @@ fun AddSourceScreen(
             )
             if (state.isEditing && !state.canDelete) {
                 Text(
-                    "This is the only server. Add another before you can remove this one.",
+                    "This is the active server. Switch to another server before deleting it.",
                     style = MaterialTheme.typography.bodySmall,
                     color = MaterialTheme.colorScheme.onSurfaceVariant,
                 )

app/src/main/kotlin/com/subtracks/ui/settings/AddSourceViewModel.kt

@@ -59,7 +59,8 @@ class AddSourceViewModel(
         }
         viewModelScope.launch {
             sourceRepository.sources().collect { sources ->
-                _state.update { it.copy(canDelete = sources.size > 1) }
+                val active = sources.any { it.id == sourceId && it.isActive }
+                _state.update { it.copy(canDelete = !active) }
             }
         }
     }
@@ -145,7 +146,7 @@ class AddSourceViewModel(
         viewModelScope.launch {
             if (!sourceRepository.deleteSource(id)) {
                 _state.update {
-                    it.copy(busy = false, message = "At least one server is required", isError = true)
+                    it.copy(busy = false, message = "The active server can't be deleted; switch to another server first", isError = true)
                 }
                 return@launch
             }

app/src/main/kotlin/com/subtracks/ui/settings/SettingsScreen.kt

@@ -19,8 +19,8 @@ import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.automirrored.rounded.ArrowBack
-import androidx.compose.material.icons.automirrored.rounded.KeyboardArrowRight
 import androidx.compose.material.icons.rounded.Add
+import androidx.compose.material.icons.rounded.Edit
 import androidx.compose.material3.AlertDialog
 import androidx.compose.material3.Button
 import androidx.compose.material3.ExperimentalMaterial3Api
@@ -140,9 +140,11 @@ fun SettingsScreen(
                         )
                     },
                     trailingContent = {
-                        Icon(Icons.AutoMirrored.Rounded.KeyboardArrowRight, contentDescription = null)
+                        IconButton(onClick = { onEditServer(source.id) }) {
+                            Icon(Icons.Rounded.Edit, contentDescription = "Edit ${source.name}")
+                        }
                     },
-                    modifier = Modifier.clickable(onClickLabel = "Edit ${source.name}") { onEditServer(source.id) },
+                    modifier = Modifier.clickable(onClickLabel = "Use ${source.name}") { onSelectSource(source.id) },
                     colors = ListItemDefaults.colors(containerColor = Color.Transparent),
                 )
             }

app/src/test/kotlin/com/subtracks/data/repo/SourceRepositoryTest.kt

@@ -105,19 +105,21 @@ class SourceRepositoryTest {
         }
 
     @Test
-    fun theLastSourceCannotBeDeleted() =
+    fun theActiveSourceCannotBeDeleted() =
         runTest {
-            repository.addSource("only", "http://a.example", "u", "p", true)
-            val id = repository.activeSourceId().first()!!
-
-            assertFalse("the last source must survive deletion", repository.deleteSource(id))
-            assertEquals(1, repository.sources().first().size)
-
+            repository.addSource("first", "http://a.example", "u", "p", true)
+            val firstId = repository.activeSourceId().first()!!
             repository.addSource("second", "http://b.example", "u", "p", true)
+            val secondId = repository.activeSourceId().first()!!
 
-            assertTrue(repository.deleteSource(id))
-            assertEquals(listOf("second"), repository.sources().first().map { it.name })
-            assertEquals("second", repository.activeConfig().first()?.name)
+            assertFalse("the active source must survive deletion", repository.deleteSource(secondId))
+            assertEquals(2, repository.sources().first().size)
+
+            repository.selectSource(firstId)
+
+            assertTrue(repository.deleteSource(secondId))
+            assertEquals(listOf("first"), repository.sources().first().map { it.name })
+            assertEquals("first", repository.activeConfig().first()?.name)
         }
 
     @Test