feat(agent): a setup step that prepares fast Lab builds for the installed version, kept alive while it runs

app/src/main/java/com/droiddeck/launcher/agent/AgentHost.kt

@@ -378,7 +378,7 @@ object AgentHost {
         now = SystemClock.elapsedRealtime()
         appContext?.let { app ->
             lab = LabProgress.read(LinuxRuntime.rootDir(app))
-            if (state == State.WORKING) AgentHostService.update(app)
+            AgentHostService.update(app)
         }
         main.postDelayed(::tick, if (state == State.WORKING || lab != null) TICK_MS else IDLE_TICK_MS)
     }

app/src/main/java/com/droiddeck/launcher/agent/AgentHostService.kt

@@ -18,6 +18,7 @@ class AgentHostService : Service() {
 
     override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
         if (intent?.action == ACTION_STOP) {
+            if (AgentHost.lab?.running == true) AgentHost.cancelLabBuild(this)
             AgentHost.stop(this)
             return START_NOT_STICKY
         }
@@ -30,19 +31,35 @@ class AgentHostService : Service() {
         private const val NOTIFICATION_ID = 4107
         private const val ACTION_STOP = "com.droiddeck.launcher.agent.STOP"
         private var lastText: String? = null
+        @Volatile private var started = false
+        /** Setup steps that keep the app alive while they run, besides the agent's turn. */
+        private var setupSteps = 0
 
         fun start(context: Context) {
             lastText = null
+            started = true
             runCatching { context.startForegroundService(Intent(context, AgentHostService::class.java)) }
         }
 
         fun stop(context: Context) {
+            if (setupSteps > 0) return
+            started = false
             context.stopService(Intent(context, AgentHostService::class.java))
         }
 
+        fun setupStarted(context: Context) {
+            setupSteps++
+            start(context)
+        }
+
+        fun setupEnded(context: Context) {
+            setupSteps = (setupSteps - 1).coerceAtLeast(0)
+            if (AgentHost.state != AgentHost.State.WORKING) stop(context)
+        }
+
         /** Refreshes the notification with the current step; unchanged text is not re-posted. */
         fun update(context: Context) {
-            if (AgentHost.state != AgentHost.State.WORKING) return
+            if (!started) return
             val text = describe(context)
             if (text == lastText) return
             lastText = text
@@ -52,6 +69,7 @@ class AgentHostService : Service() {
         private fun describe(context: Context): String {
             val lab = AgentHost.lab?.takeIf { it.running }
             if (lab != null) return context.getString(R.string.agent_lab_progress, lab.permille / 10, minutes(lab.etaSeconds.toLong()))
+            if (AgentHost.state != AgentHost.State.WORKING) return context.getString(R.string.agent_setting_up)
             val tool = AgentHost.running()
             val elapsed = minutes((SystemClock.elapsedRealtime() - AgentHost.turnStarted) / 1000)
             return if (tool != null) "${tool.tool} · ${tool.detail}".take(120) + " · $elapsed" else context.getString(R.string.agent_thinking_for, elapsed)

app/src/main/java/com/droiddeck/launcher/agent/AgentSetup.kt

@@ -17,7 +17,7 @@ import java.util.concurrent.TimeUnit
  * and to make Lab builds on the device.
  */
 object AgentSetup {
-    enum class Step(val required: Boolean) { CONNECTION(true), INSTALL(true), SIGN_IN(true), GITHUB(false), BUILD_TOOLS(false) }
+    enum class Step(val required: Boolean) { CONNECTION(true), INSTALL(true), SIGN_IN(true), GITHUB(false), BUILD_TOOLS(false), PREPARE(false) }
     enum class Status { UNKNOWN, DONE, TODO, WORKING, FAILED }
 
     val status = mutableStateMapOf<Step, Status>()
@@ -48,8 +48,8 @@ object AgentSetup {
         for (step in Step.entries) if (status[step] != Status.WORKING) {
             when (step) {
                 Step.INSTALL -> set(step, if (AgentHost.guestFileExists(app, harness.binary)) Status.DONE else Status.TODO)
-                Step.BUILD_TOOLS -> set(step, if (AgentHost.guestFileExists(app, "/root/aapt2/aapt2") &&
-                    AgentHost.guestFileExists(app, "$CHECKOUT/.git")) Status.DONE else Status.TODO)
+                Step.BUILD_TOOLS -> set(step, if (buildToolsInstalled(app)) Status.DONE else Status.TODO)
+                Step.PREPARE -> set(step, if (prepared(app)) Status.DONE else Status.TODO)
                 Step.CONNECTION -> probes += step to listOf("sh", "-c",
                     "for i in 1 2 3; do adb connect \"\$ADB_SERIAL\" >/dev/null 2>&1; " +
                         "adb -s \"\$ADB_SERIAL\" get-state 2>&1 | tee /dev/stderr | grep -q device && exit 0; sleep 1; done; exit 1")
@@ -74,9 +74,11 @@ object AgentSetup {
             Step.GITHUB -> listOf("dd-gh-login")
             Step.BUILD_TOOLS -> listOf("sh", "-c", "set -e; [ -d $CHECKOUT/.git ] || git clone --filter=blob:none $REPO $CHECKOUT; " +
                 "cd $CHECKOUT; [ -x tools/agent/setup ] || { echo 'This DroidDeck version has no tools/agent/setup yet'; exit 1; }; tools/agent/setup")
+            Step.PREPARE -> listOf("sh", "-c", "cd $CHECKOUT && dd-lab-build --prepare")
         }
         set(step, Status.WORKING)
         detail.remove(step)
+        AgentHostService.setupStarted(app)
         Thread({
             val result = runCatching {
                 if (step == Step.INSTALL) installHelpers(app)
@@ -89,6 +91,7 @@ object AgentSetup {
                 child.waitFor()
             }
             main.post {
+                AgentHostService.setupEnded(app)
                 if (result.getOrNull() == 0) {
                     detail.remove(step)
                     status[step] = Status.UNKNOWN
@@ -101,6 +104,14 @@ object AgentSetup {
         }, "agent-setup-${step.name.lowercase()}").start()
     }
 
+    fun buildToolsInstalled(app: Context) = AgentHost.guestFileExists(app, "/root/aapt2/aapt2") && AgentHost.guestFileExists(app, "$CHECKOUT/.git")
+
+    /** dd-lab-build compiled this install's commit, so a Lab build compiles only what changed. */
+    private fun prepared(app: Context) = runCatching {
+        File(LinuxRuntime.rootDir(app), "root/.cache/dd-lab-build-base").readText().trim()
+            .startsWith(com.droiddeck.launcher.lab.LabOverlay.apkCommit.take(7))
+    }.getOrDefault(false)
+
     /** Drops what the checks found, which belonged to the previous harness. */
     fun forget() {
         status.clear()

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

@@ -65,7 +65,10 @@ internal fun AgentSetupView(modifier: Modifier, onDone: () -> Unit = {}) {
             steps.forEachIndexed { index, step ->
                 val status = AgentSetup.status[step] ?: Status.UNKNOWN
                 val (title, hint) = labels(step, AgentHost.harness.name)
-                val detail = AgentSetup.detail[step] ?: hint
+                val lab = AgentHost.lab?.takeIf { it.prepare && it.running }
+                val detail = if (step == Step.PREPARE && lab != null)
+                    stringResource(R.string.agent_prepare_progress, lab.permille / 10, clock(lab.etaSeconds.toLong().coerceAtLeast(0)))
+                else AgentSetup.detail[step] ?: hint
                 CheckRow(
                     when (status) {
                         Status.DONE -> CheckState.OK
@@ -74,7 +77,8 @@ internal fun AgentSetupView(modifier: Modifier, onDone: () -> Unit = {}) {
                     },
                     title, detail, divider = index < steps.lastIndex,
                 ) {
-                    val blocked = step == Step.SIGN_IN && AgentSetup.status[Step.INSTALL] != Status.DONE
+                    val blocked = (step == Step.SIGN_IN && AgentSetup.status[Step.INSTALL] != Status.DONE) ||
+                        (step == Step.PREPARE && AgentSetup.status[Step.BUILD_TOOLS] != Status.DONE)
                     if ((status == Status.TODO || status == Status.FAILED) && !blocked) {
                         val label = stringResource(if (status == Status.FAILED) R.string.agent_setup_retry else action(step))
                         val run = { if (step == Step.CONNECTION) pair(context) else AgentSetup.run(context, step) }
@@ -151,6 +155,7 @@ private fun labels(step: Step, harness: String): Pair<String, String> = when (st
     Step.SIGN_IN -> stringResource(R.string.agent_step_sign_in, harness) to stringResource(R.string.agent_step_sign_in_hint)
     Step.GITHUB -> stringResource(R.string.agent_step_github) to stringResource(R.string.agent_step_github_hint)
     Step.BUILD_TOOLS -> stringResource(R.string.agent_step_build) to stringResource(R.string.agent_step_build_hint)
+    Step.PREPARE -> stringResource(R.string.agent_step_prepare) to stringResource(R.string.agent_step_prepare_hint)
 }
 
 private fun action(step: Step): Int = when (step) {
@@ -158,6 +163,7 @@ private fun action(step: Step): Int = when (step) {
     Step.INSTALL -> R.string.agent_action_install
     Step.SIGN_IN, Step.GITHUB -> R.string.agent_action_sign_in
     Step.BUILD_TOOLS -> R.string.agent_action_install
+    Step.PREPARE -> R.string.agent_action_prepare
 }
 
 /** The pairing DroidDeck already uses for the phantom process fix; the agent reuses its key. */

app/src/main/res/values/strings.xml

@@ -1164,6 +1164,7 @@
     <string name="agent_failed">Failed: %1$s</string>
     <string name="agent_exited">%1$s ended (exit %2$d)</string>
     <string name="agent_stopped">Stopped</string>
+    <string name="agent_setting_up">Setting up the agent</string>
     <string name="agent_rebuild_lab">Rebuild my Lab build %1$s for the installed version of DroidDeck and restart on it.</string>
     <string name="agent_tokens">%1$s in · %2$s out</string>
     <string name="agent_thinking">Thinking</string>
@@ -1220,6 +1221,10 @@
     <string name="agent_step_github_hint">Optional, to open pull requests</string>
     <string name="agent_step_build">Build tools</string>
     <string name="agent_step_build_hint">Optional, for Lab builds on this device · about 5 GB</string>
+    <string name="agent_step_prepare">Fast Lab builds</string>
+    <string name="agent_step_prepare_hint">Compiles this version ahead, so Lab builds take minutes · about 20 minutes once</string>
+    <string name="agent_prepare_progress">Compiling · %1$d%% · about %2$s left</string>
+    <string name="agent_action_prepare">Prepare</string>
     <string name="agent_action_pair">Pair</string>
     <string name="agent_action_install">Install</string>
     <string name="agent_action_sign_in">Sign in</string>