feat(session): explain paused sessions and offer stop

app/src/main/java/com/droiddeck/launcher/SessionActivity.kt

@@ -355,9 +355,12 @@ class SessionActivity : ComponentActivity(), SurfaceHolder.Callback {
                         onComponentsRefresh = { refreshDrawerComponents() },
                         onComponentSwap = { pid, comp, value -> swapDrawerComponent(pid, comp, value) },
                     ))
-                    if (SessionState.suspended) SessionPausedOverlay {
-                        SessionService.resume(this@SessionActivity)
-                    }
+                    if (SessionState.suspended) SessionPausedOverlay(
+                        title = pausedTitle(),
+                        onResume = { SessionService.resume(this@SessionActivity) },
+                        // As the drawer's Stop does; stopping resumes the paused processes first.
+                        onStop = { SessionService.stop(this@SessionActivity); finish() },
+                    )
                 }
             }
         }
@@ -475,6 +478,12 @@ class SessionActivity : ComponentActivity(), SurfaceHolder.Callback {
         if (SessionState.running) SessionState.mode
         else intent.getStringExtra(SessionService.EXTRA_MODE) ?: SessionService.MODE_STEAM
 
+    private fun pausedTitle(): String = when (SessionState.mode) {
+        SessionService.MODE_DESKTOP -> "The desktop is paused"
+        SessionService.MODE_RUN -> (com.droiddeck.launcher.frontend.Library.nameForProgram(SessionState.program) ?: "The program") + " is paused"
+        else -> "Steam is paused"
+    }
+
     private fun loadingTitle(): String = when (loadingMode()) {
         SessionService.MODE_DESKTOP ->
             if (!SessionState.running && intent.getStringExtra(SessionService.EXTRA_STEAM_UI) != null) "Starting Steam on the desktop"

app/src/main/java/com/droiddeck/launcher/ui/FrontEndScreen.kt

@@ -1733,6 +1733,7 @@ internal fun PrimaryButton(
     enabled: Boolean = true,
     main: Boolean = false,
     compact: Boolean = false,
+    modifier: Modifier = Modifier,
     onClick: () -> Unit,
 ) {
     val colors = MaterialTheme.colorScheme
@@ -1751,7 +1752,7 @@ internal fun PrimaryButton(
     val lift by animateFloatAsState(if (hot) 14f else 6f, Motion.tw(300), label = "btnLift")
     Row(
         verticalAlignment = Alignment.CenterVertically, horizontalArrangement = Arrangement.spacedBy(8.dp),
-        modifier = track
+        modifier = modifier.then(track)
             .then(if (frontFocus != null) Modifier.focusRequester(frontFocus.primary).onFocusChanged { if (it.isFocused) frontFocus.last = FrontFocus.PRIMARY } else Modifier)
             .graphicsLayer { scaleX = scale; scaleY = scale; shadowElevation = if (enabled) lift.dp.toPx() else 0f; shape = Shape12; clip = false; ambientShadowColor = pal.signal; spotShadowColor = pal.signal }
             .clip(Shape12)
@@ -1768,7 +1769,7 @@ internal fun PrimaryButton(
 }
 
 @Composable
-internal fun SecondaryButton(text: String, enabled: Boolean = true, compact: Boolean = false, onClick: () -> Unit) {
+internal fun SecondaryButton(text: String, enabled: Boolean = true, compact: Boolean = false, modifier: Modifier = Modifier, onClick: () -> Unit) {
     val colors = MaterialTheme.colorScheme
     val src = remember { MutableInteractionSource() }
     val hot = rememberHot(src) && enabled
@@ -1778,7 +1779,7 @@ internal fun SecondaryButton(text: String, enabled: Boolean = true, compact: Boo
     val edge by animateColorAsState(if (hot) pal.signal else pal.line2, Motion.tw(250), label = "secEdge")
     val fill by animateColorAsState(if (hot) pal.signal.copy(alpha = 0.14f) else Color.White.copy(alpha = 0.03f), Motion.tw(250), label = "secFill")
     Box(
-        modifier = Modifier.paneItem("btn:$text").downToFirstTile().graphicsLayer { scaleX = scale; scaleY = scale }.clip(Shape12).background(fill).border(1.dp, edge, Shape12)
+        modifier = modifier.paneItem("btn:$text").downToFirstTile().graphicsLayer { scaleX = scale; scaleY = scale }.clip(Shape12).background(fill).border(1.dp, edge, Shape12)
             .alpha(if (enabled) 1f else 0.5f)
             .hoverable(src).clickable(interactionSource = src, indication = LocalIndication.current, enabled = enabled, onClick = onClick)
             .controllerConfirm(enabled = enabled, onClick = onClick)

app/src/main/java/com/droiddeck/launcher/ui/SessionOverlay.kt

@@ -5,6 +5,7 @@ import androidx.compose.animation.core.tween
 import androidx.compose.foundation.layout.offset
 import androidx.compose.material.icons.Icons
 import androidx.compose.foundation.layout.heightIn
+import androidx.compose.material.icons.filled.Pause
 import androidx.compose.material.icons.outlined.Menu
 import androidx.compose.material.icons.outlined.MoreHoriz
 import androidx.compose.material.icons.outlined.PowerSettingsNew
@@ -291,10 +292,17 @@ private fun StageRow(label: String, state: StageMark, detail: String, percent: I
     }
 }
 
+/**
+ * A session paused in the background (the Manual background behaviour): what is paused, that it
+ * picks up where it left off, and the two ways on - Resume first, for the pad.
+ */
 @Composable
-fun SessionPausedOverlay(onResume: () -> Unit) {
+fun SessionPausedOverlay(title: String = "Steam is paused", onResume: () -> Unit, onStop: (() -> Unit)? = null) {
+    val colors = MaterialTheme.colorScheme
+    val pal = LocalPalette.current
     val interactionSource = remember { MutableInteractionSource() }
     val resumeFocus = remember { FocusRequester() }
+    var confirmStop by remember { mutableStateOf(false) }
     LaunchedEffect(Unit) {
         androidx.compose.runtime.withFrameNanos { }
         runCatching { resumeFocus.requestFocus() }
@@ -302,22 +310,55 @@ fun SessionPausedOverlay(onResume: () -> Unit) {
     Box(
         modifier = Modifier
             .fillMaxSize()
-            .background(Color(0xF20B0D10))
+            .background(pal.background.copy(alpha = 0.94f))
             .clickable(interactionSource = interactionSource, indication = null) {},
         contentAlignment = Alignment.Center,
     ) {
         Column(
             horizontalAlignment = Alignment.CenterHorizontally,
-            modifier = Modifier.padding(32.dp),
+            verticalArrangement = Arrangement.spacedBy(10.dp),
+            modifier = Modifier.widthIn(max = 440.dp).padding(32.dp),
         ) {
-            OutlinedButton(
-                onClick = onResume,
-                modifier = Modifier.focusRequester(resumeFocus).controllerConfirm(onClick = onResume),
-            ) {
-                Text("Resume session")
+            Box(contentAlignment = Alignment.Center, modifier = Modifier.padding(bottom = 6.dp).size(64.dp).border(2.dp, pal.line2, CircleShape)) {
+                Icon(Icons.Filled.Pause, contentDescription = null, tint = colors.onBackground, modifier = Modifier.size(30.dp))
+            }
+            Text(title, fontSize = 28.sp, fontWeight = FontWeight.Bold, color = colors.onBackground, textAlign = TextAlign.Center)
+            Text(
+                "It stopped while DroidDeck was in the background and picks up where it left off.",
+                fontSize = 15.sp, lineHeight = 21.sp, color = colors.onSurfaceVariant, textAlign = TextAlign.Center,
+            )
+            Row(horizontalArrangement = Arrangement.spacedBy(10.dp), modifier = Modifier.padding(top = 14.dp)) {
+                PrimaryButton("Resume", modifier = Modifier.focusRequester(resumeFocus).controllerConfirm(onClick = onResume), onClick = onResume)
+                if (onStop != null) SecondaryButton("Stop session") { confirmStop = true }
             }
         }
     }
+    if (confirmStop && onStop != null) {
+        val cancelFocus = remember { FocusRequester() }
+        val cancel = { confirmStop = false }
+        val stop = { confirmStop = false; onStop() }
+        LaunchedEffect(Unit) {
+            androidx.compose.runtime.withFrameNanos { }
+            runCatching { cancelFocus.requestFocus() }
+        }
+        // Opens on Cancel, as the menu's does: a stray A press never ends the session.
+        AlertDialog(
+            onDismissRequest = cancel,
+            modifier = Modifier.controllerBack(onBack = cancel),
+            title = { Text("Stop session?") },
+            text = { Text("Everything running in this session closes.") },
+            confirmButton = {
+                TextButton(
+                    onClick = stop,
+                    modifier = Modifier.controllerConfirm(onClick = stop),
+                    colors = ButtonDefaults.textButtonColors(contentColor = colors.error),
+                ) { Text("Stop") }
+            },
+            dismissButton = {
+                TextButton(onClick = cancel, modifier = Modifier.focusRequester(cancelFocus).controllerConfirm(onClick = cancel)) { Text("Cancel") }
+            },
+        )
+    }
 }
 
 /** Everything the drawer shows and does. */