2 files changed, 77 insertions, 0 deletions

diff --git a/app/src/main/java/org/terst/listen/ui/SubscriptionScreen.kt b/app/src/main/java/org/terst/listen/ui/SubscriptionScreen.kt
index f15debd..70f48e5 100644
--- a/app/src/main/java/org/terst/listen/ui/SubscriptionScreen.kt
+++ b/app/src/main/java/org/terst/listen/ui/SubscriptionScreen.kt
@@ -31,6 +31,9 @@ import androidx.compose.material3.TopAppBar
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.LaunchedEffect
 import androidx.compose.runtime.collectAsState
+import androidx.compose.material.icons.filled.Delete
+import androidx.compose.material3.AlertDialog
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.getValue
 import androidx.compose.runtime.mutableStateOf
 import androidx.compose.runtime.remember
@@ -53,6 +56,7 @@ fun SubscriptionScreen(
     onBack: () -> Unit,
 ) {
     val episodes by vm.episodesOf(subscriptionId).collectAsState(initial = emptyList())
+    var confirming by remember { mutableStateOf(false) }
     val subscription = vm.subscriptions.collectAsState().value.firstOrNull { it.id == subscriptionId }
 
     Scaffold(
@@ -64,9 +68,27 @@ fun SubscriptionScreen(
                         Icon(Icons.AutoMirrored.Filled.ArrowBack, contentDescription = "Back")
                     }
                 },
+                actions = {
+                    IconButton(onClick = { confirming = true }) {
+                        Icon(Icons.Default.Delete, contentDescription = "Unsubscribe")
+                    }
+                },
             )
         },
     ) { padding ->
+        // Confirmed, because unsubscribing cascades: the episodes go, and with them every
+        // playback position and played mark for that show. None of it is recoverable.
+        UnsubscribeDialog(
+            visible = confirming,
+            showTitle = subscription?.title,
+            onDismiss = { confirming = false },
+            onConfirm = {
+                confirming = false
+                vm.unsubscribe(subscriptionId)
+                onBack()
+            },
+        )
+
         LazyColumn(Modifier.padding(padding).fillMaxSize()) {
             items(episodes, key = { it.id }) { episode ->
                 EpisodeRow(
@@ -87,3 +109,26 @@ fun SubscriptionScreen(
     }
 }
 
+/** Confirmed, because unsubscribing cascades: episodes, downloads and every playback position
+ *  for that show go with it, and none of it is recoverable. */
+@Composable
+private fun UnsubscribeDialog(
+    visible: Boolean,
+    showTitle: String?,
+    onDismiss: () -> Unit,
+    onConfirm: () -> Unit,
+) {
+    if (!visible) return
+    AlertDialog(
+        onDismissRequest = onDismiss,
+        title = { Text("Unsubscribe?") },
+        text = {
+            Text(
+                "Removes ${showTitle ?: "this podcast"} along with its episodes, downloads and " +
+                    "playback positions."
+            )
+        },
+        confirmButton = { TextButton(onClick = onConfirm) { Text("Unsubscribe") } },
+        dismissButton = { TextButton(onClick = onDismiss) { Text("Cancel") } },
+    )
+}
diff --git a/app/src/test/java/org/terst/listen/ReachabilityTest.kt b/app/src/test/java/org/terst/listen/ReachabilityTest.kt
index ccd603a..6a33380 100644
--- a/app/src/test/java/org/terst/listen/ReachabilityTest.kt
+++ b/app/src/test/java/org/terst/listen/ReachabilityTest.kt
@@ -106,6 +106,38 @@ class ReachabilityTest {
             dead.isEmpty())
     }
 
+    /**
+     * View models are the third place this has hidden. A function here with no screen calling
+     * it is not merely unused -- it is a feature the user cannot reach, which is how "you
+     * cannot unsubscribe from a podcast" survived a whole phase.
+     */
+    @Test
+    fun `every view model function is reachable from a screen`() {
+        val uiDir = File(mainDir, "ui")
+        val viewModels = uiDir.listFiles { f: File -> f.name.endsWith("ViewModel.kt") }?.toList()
+        assertTrue("expected view models under ${uiDir.path}", !viewModels.isNullOrEmpty())
+
+        val screens = uiDir.walkTopDown()
+            .filter { it.extension == "kt" && !it.name.endsWith("ViewModel.kt") }
+            .joinToString("\n") { it.readText() }
+
+        val dead = viewModels!!.flatMap { file ->
+            Regex("""^    fun (\w+)""", RegexOption.MULTILINE).findAll(file.readText())
+                .map { it.groupValues[1] }
+                .filterNot { it in allowedViewModelFunctions }
+                // A screen may call it directly or pass it as a reference (vm::refreshAll).
+                .filterNot { screens.contains("$it(") || screens.contains("::$it") }
+                .toList()
+        }
+
+        assertTrue(
+            "No screen reaches: ${dead.sorted()}. These are features the user cannot get to.",
+            dead.isEmpty(),
+        )
+    }
+
+    private val allowedViewModelFunctions = emptySet<String>()
+
     @Test
     fun `every helper object function has a caller`() {
         val sources = mainDir.walkTopDown().filter { it.extension == "kt" }.toList()