feat(kiosk): ask if scale is present; check+update gateway in wizard

Wizard step 3 — 'Do you have a Bluetooth smart scale?':
- New question card with two buttons shown first:
    ✅ Yes → reveal gateway status card + bottom nav buttons
    ➡️ No  → save KEY_HAS_SCALE=false, skip to web view
- KEY_HAS_SCALE pref controls whether the gateway is auto-launched
  both after wizard completion and on every subsequent app start
- checkGatewayStatus(): uses string resources (multilingual)
- checkGatewayUpdate(): fetches GitHub release, compares version;
  if gateway needs an update shows '📥 Update Scale Gateway' button
  that triggers triggerApkDownload() (full PackageInstaller flow)
- onResume step-3 re-check only fires when status card is visible
  (i.e. user already answered 'Yes') — handles return from install

Multi-language: strings.xml added for EN (default), IT, DE
strings: wizard_step3_question/yes/no, wizard_gateway_installed/
  not_installed/checking/up_to_date/update_available/update_detail,
  btn_back/launch/launch_no_scale/download_gateway/update_gateway

evershelf-kiosk/app/src/main/kotlin/it/dadaloop/evershelf/kiosk/KioskActivity.kt

@@ -77,6 +77,8 @@ class KioskActivity : AppCompatActivity() {
     private lateinit var scaleStatusIcon: TextView
     private lateinit var scaleStatusText: TextView
     private lateinit var scaleStatusDetail: TextView
+    private lateinit var scaleQuestionLayout: LinearLayout
+    private lateinit var step3BottomButtons: LinearLayout
     // Update banner (native, shown at the top over the WebView)
     private lateinit var updateBanner: LinearLayout
     private lateinit var tvUpdateMessage: TextView
@@ -106,6 +108,7 @@ class KioskActivity : AppCompatActivity() {
         private const val PREFS_NAME = "evershelf_kiosk"
         private const val KEY_URL = "evershelf_url"
         private const val KEY_SETUP_COMPLETE = "setup_complete"
+        private const val KEY_HAS_SCALE = "has_scale"
         private const val GATEWAY_PACKAGE = "it.dadaloop.evershelf.scalegate"
         private const val GATEWAY_DOWNLOAD_URL = "https://github.com/dadaloop82/EverShelf/releases/latest/download/evershelf-scale-gateway.apk"
         private const val KIOSK_DOWNLOAD_URL = "https://github.com/dadaloop82/EverShelf/releases/latest/download/evershelf-kiosk.apk"
@@ -166,6 +169,8 @@ class KioskActivity : AppCompatActivity() {
         scaleStatusIcon = findViewById(R.id.scaleStatusIcon)
         scaleStatusText = findViewById(R.id.scaleStatusText)
         scaleStatusDetail = findViewById(R.id.scaleStatusDetail)
+        scaleQuestionLayout = findViewById(R.id.scaleQuestionLayout)
+        step3BottomButtons = findViewById(R.id.step3BottomButtons)
 
         // Update banner
         updateBanner    = findViewById(R.id.updateBanner)
@@ -204,10 +209,21 @@ class KioskActivity : AppCompatActivity() {
             goToStep(2)
         }
         findViewById<MaterialButton>(R.id.btnFinish).setOnClickListener {
+            prefs.edit().putBoolean(KEY_HAS_SCALE, true).apply()
             launchGatewayInBackground()
             finishWizard()
         }
-        findViewById<MaterialButton>(R.id.btnSkipScale).setOnClickListener {
+        // "Yes" → reveal gateway status and proceed flow
+        findViewById<MaterialButton>(R.id.btnScaleYes).setOnClickListener {
+            scaleQuestionLayout.visibility = View.GONE
+            val statusCard = findViewById<LinearLayout>(R.id.scaleStatusCard)
+            statusCard.visibility = View.VISIBLE
+            step3BottomButtons.visibility = View.VISIBLE
+            checkGatewayStatus()
+        }
+        // "No" → save pref and skip to web view
+        findViewById<MaterialButton>(R.id.btnScaleNo).setOnClickListener {
+            prefs.edit().putBoolean(KEY_HAS_SCALE, false).apply()
             finishWizard()
         }
 
@@ -320,7 +336,12 @@ class KioskActivity : AppCompatActivity() {
         updateStepIndicator()
 
         if (step == 3) {
-            checkGatewayStatus()
+            // Reset to question state every time step 3 is entered
+            scaleQuestionLayout.visibility = View.VISIBLE
+            val statusCard = findViewById<LinearLayout>(R.id.scaleStatusCard)
+            statusCard.visibility = View.GONE
+            step3BottomButtons.visibility = View.GONE
+            findViewById<MaterialButton>(R.id.btnSkipScale).visibility = View.GONE
         }
     }
 
@@ -376,6 +397,7 @@ class KioskActivity : AppCompatActivity() {
     }
 
     private fun launchGatewayInBackground() {
+        if (!prefs.getBoolean(KEY_HAS_SCALE, false)) return
         if (!isGatewayInstalled()) return
         val launchIntent = packageManager.getLaunchIntentForPackage(GATEWAY_PACKAGE) ?: return
         launchIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
@@ -389,32 +411,93 @@ class KioskActivity : AppCompatActivity() {
 
     private fun checkGatewayStatus() {
         if (isGatewayInstalled()) {
-            scaleStatusIcon.text = "✅"
+            scaleStatusIcon.text = "\u2705"
-            scaleStatusText.text = "Scale Gateway is installed"
+            scaleStatusText.text = getString(R.string.wizard_gateway_installed)
-            scaleStatusDetail.text = "It will be launched in the background when you proceed"
+            scaleStatusDetail.text = getString(R.string.wizard_gateway_checking)
-            scaleStatusDetail.setTextColor(0xFF34d399.toInt())
+            scaleStatusDetail.setTextColor(0xFF94a3b8.toInt())
             findViewById<MaterialButton>(R.id.btnSkipScale).visibility = View.GONE
-            findViewById<MaterialButton>(R.id.btnFinish).text = "🚀  Launch EverShelf"
+            findViewById<MaterialButton>(R.id.btnFinish).text = getString(R.string.btn_launch)
+            // Check async if a newer version is available
+            checkGatewayUpdate()
         } else {
-            scaleStatusIcon.text = "📥"
+            scaleStatusIcon.text = "\uD83D\uDCE5"
-            scaleStatusText.text = "Scale Gateway not installed"
+            scaleStatusText.text = getString(R.string.wizard_gateway_not_installed)
-            scaleStatusDetail.text = "Install the Scale Gateway app to use a Bluetooth scale"
+            scaleStatusDetail.text = getString(R.string.wizard_gateway_not_installed_detail)
             scaleStatusDetail.setTextColor(0xFFfbbf24.toInt())
-
+            findViewById<MaterialButton>(R.id.btnFinish).text = getString(R.string.btn_launch_no_scale)
-            findViewById<MaterialButton>(R.id.btnFinish).text = "🚀  Launch without scale"
-
             findViewById<MaterialButton>(R.id.btnSkipScale).apply {
-                text = "📥  Download Scale Gateway"
+                text = getString(R.string.btn_download_gateway)
-                setTextColor(0xFF7c3aed.toInt())
+                setTextColor(0xFFa78bfa.toInt())
                 visibility = View.VISIBLE
-                setOnClickListener {
+                setOnClickListener { triggerApkDownload(GATEWAY_DOWNLOAD_URL) }
-                    val intent = Intent(Intent.ACTION_VIEW, Uri.parse(GATEWAY_DOWNLOAD_URL))
-                    startActivity(intent)
-                }
             }
         }
     }
 
+    /** Fetches the latest GitHub release and, if the gateway has an available update,
+     *  shows the update button in the wizard status card. */
+    private fun checkGatewayUpdate() {
+        val currentVersion = try {
+            packageManager.getPackageInfo(GATEWAY_PACKAGE, 0).versionName ?: return
+        } catch (_: Exception) { return }
+
+        Thread {
+            try {
+                val conn = URL(GITHUB_RELEASES_API).openConnection() as java.net.HttpURLConnection
+                conn.setRequestProperty("Accept", "application/vnd.github+json")
+                conn.connectTimeout = 5000
+                conn.readTimeout = 5000
+                val json = JSONObject(conn.inputStream.bufferedReader().readText())
+                conn.disconnect()
+
+                val latestTag = json.optString("tag_name", "")
+                if (latestTag.isEmpty()) { showGatewayUpToDate(); return@Thread }
+
+                val isSemver = latestTag.trimStart('v').matches(Regex("\\d+\\.\\d+.*"))
+                val norm = { v: String -> v.trimStart('v') }
+                val needsUpdate = !isSemver || norm(latestTag) != norm(currentVersion)
+
+                if (!needsUpdate) { showGatewayUpToDate(); return@Thread }
+
+                // Locate the gateway APK among release assets
+                var apkUrl = GATEWAY_DOWNLOAD_URL
+                val assets = json.optJSONArray("assets")
+                if (assets != null) {
+                    for (i in 0 until assets.length()) {
+                        val a = assets.getJSONObject(i)
+                        val name = a.optString("name", "").lowercase()
+                        val url  = a.optString("browser_download_url", "")
+                        if ((name.contains("gateway") || name.contains("scale")) && url.isNotEmpty()) {
+                            apkUrl = url; break
+                        }
+                    }
+                }
+                val finalUrl = apkUrl
+                runOnUiThread {
+                    scaleStatusIcon.text = "\uD83D\uDD04"
+                    scaleStatusText.text = getString(R.string.wizard_gateway_update_available)
+                    scaleStatusDetail.text = getString(R.string.wizard_gateway_update_detail)
+                    scaleStatusDetail.setTextColor(0xFFfbbf24.toInt())
+                    pendingInstallPkg = GATEWAY_PACKAGE
+                    pendingApkDownloadUrl = finalUrl
+                    findViewById<MaterialButton>(R.id.btnSkipScale).apply {
+                        text = getString(R.string.btn_update_gateway)
+                        setTextColor(0xFFfbbf24.toInt())
+                        visibility = View.VISIBLE
+                        setOnClickListener { triggerApkDownload(finalUrl) }
+                    }
+                }
+            } catch (_: Exception) {
+                showGatewayUpToDate()
+            }
+        }.start()
+    }
+
+    private fun showGatewayUpToDate() = runOnUiThread {
+        scaleStatusDetail.text = getString(R.string.wizard_gateway_installed_detail)
+        scaleStatusDetail.setTextColor(0xFF34d399.toInt())
+    }
+
     // ── Connection Test ───────────────────────────────────────────────────
 
     private fun testConnection() {
@@ -996,7 +1079,9 @@ class KioskActivity : AppCompatActivity() {
             showWizard()
         }
         if (currentStep == 3 && wizardContainer.visibility == View.VISIBLE) {
-            checkGatewayStatus()
+            val statusCard = findViewById<LinearLayout>(R.id.scaleStatusCard)
+            // Only re-check if the user has already answered "Yes" (status card visible)
+            if (statusCard.visibility == View.VISIBLE) checkGatewayStatus()
         }
     }
 

evershelf-kiosk/app/src/main/res/layout/activity_kiosk.xml

@@ -302,7 +302,7 @@
                 <TextView
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
-                    android:text="Smart Scale (Optional)"
+                    android:text="@string/wizard_step3_title"
                     android:textColor="#f1f5f9"
                     android:textSize="24sp"
                     android:textStyle="bold"
@@ -311,14 +311,56 @@
                 <TextView
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
-                    android:text="To use a Bluetooth kitchen scale, you need the EverShelf Scale Gateway app installed separately."
+                    android:text="@string/wizard_step3_description"
                     android:textColor="#94a3b8"
                     android:textSize="15sp"
                     android:gravity="center"
                     android:lineSpacingExtra="4dp"
                     android:layout_marginBottom="24dp" />
 
-                <!-- Scale status card -->
+                <!-- Scale question card — shown first, hidden after answer -->
+                <LinearLayout
+                    android:id="@+id/scaleQuestionLayout"
+                    android:layout_width="match_parent"
+                    android:layout_height="wrap_content"
+                    android:orientation="vertical"
+                    android:background="@drawable/card_background"
+                    android:padding="20dp"
+                    android:layout_marginBottom="16dp">
+
+                    <TextView
+                        android:layout_width="match_parent"
+                        android:layout_height="wrap_content"
+                        android:text="@string/wizard_step3_question"
+                        android:textColor="#f1f5f9"
+                        android:textSize="17sp"
+                        android:textStyle="bold"
+                        android:gravity="center"
+                        android:layout_marginBottom="20dp" />
+
+                    <com.google.android.material.button.MaterialButton
+                        android:id="@+id/btnScaleYes"
+                        android:layout_width="match_parent"
+                        android:layout_height="52dp"
+                        android:text="@string/wizard_step3_yes"
+                        android:textSize="15sp"
+                        android:textAllCaps="false"
+                        android:backgroundTint="#059669"
+                        android:layout_marginBottom="10dp" />
+
+                    <com.google.android.material.button.MaterialButton
+                        android:id="@+id/btnScaleNo"
+                        android:layout_width="match_parent"
+                        android:layout_height="52dp"
+                        android:text="@string/wizard_step3_no"
+                        android:textSize="15sp"
+                        android:textAllCaps="false"
+                        style="@style/Widget.MaterialComponents.Button.OutlinedButton"
+                        android:strokeColor="#334155"
+                        android:textColor="#94a3b8" />
+                </LinearLayout>
+
+                <!-- Scale status card — shown after user answers "Yes" -->
                 <LinearLayout
                     android:id="@+id/scaleStatusCard"
                     android:layout_width="match_parent"
@@ -326,7 +368,8 @@
                     android:orientation="vertical"
                     android:background="@drawable/card_background"
                     android:padding="20dp"
-                    android:layout_marginBottom="16dp">
+                    android:layout_marginBottom="16dp"
+                    android:visibility="gone">
 
                     <TextView
                         android:id="@+id/scaleStatusIcon"
@@ -357,19 +400,22 @@
                         android:gravity="center" />
                 </LinearLayout>
 
+                <!-- Bottom nav (Back / Launch) — hidden until user answers the question -->
                 <LinearLayout
+                    android:id="@+id/step3BottomButtons"
                     android:layout_width="match_parent"
                     android:layout_height="wrap_content"
                     android:orientation="horizontal"
                     android:gravity="center"
-                    android:layout_marginTop="16dp">
+                    android:layout_marginTop="16dp"
+                    android:visibility="gone">
 
                     <com.google.android.material.button.MaterialButton
                         android:id="@+id/btnStep3Back"
                         android:layout_width="0dp"
                         android:layout_height="48dp"
                         android:layout_weight="1"
-                        android:text="Back"
+                        android:text="@string/btn_back"
                         android:textSize="15sp"
                         android:textAllCaps="false"
                         style="@style/Widget.MaterialComponents.Button.OutlinedButton"
@@ -382,22 +428,24 @@
                         android:layout_width="0dp"
                         android:layout_height="56dp"
                         android:layout_weight="2"
-                        android:text="🚀  Launch EverShelf"
+                        android:text="@string/btn_launch"
                         android:textSize="16sp"
                         android:textAllCaps="false"
                         android:backgroundTint="#059669" />
                 </LinearLayout>
 
+                <!-- Install/Update gateway button — shown by checkGatewayStatus() as needed -->
                 <com.google.android.material.button.MaterialButton
                     android:id="@+id/btnSkipScale"
                     android:layout_width="wrap_content"
-                    android:layout_height="36dp"
+                    android:layout_height="wrap_content"
-                    android:text="Skip — I don't have a scale"
+                    android:textSize="14sp"
-                    android:textSize="13sp"
                     android:textAllCaps="false"
-                    style="@style/Widget.MaterialComponents.Button.TextButton"
+                    style="@style/Widget.MaterialComponents.Button.OutlinedButton"
-                    android:textColor="#64748b"
+                    android:strokeColor="#7c3aed"
-                    android:layout_marginTop="12dp" />
+                    android:textColor="#a78bfa"
+                    android:layout_marginTop="12dp"
+                    android:visibility="gone" />
             </LinearLayout>
 
         </LinearLayout>

evershelf-kiosk/app/src/main/res/values-de/strings.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">EverShelf Kiosk</string>
+
+    <!-- Wizard Schritt 3: Smart-Waage -->
+    <string name="wizard_step3_title">Smart-Waage (Optional)</string>
+    <string name="wizard_step3_description">Um eine Bluetooth-Küchenwaage zu verwenden, musst du die EverShelf Scale Gateway App separat installieren.</string>
+    <string name="wizard_step3_question">Hast du eine Bluetooth-Küchenwaage?</string>
+    <string name="wizard_step3_yes">✅  Ja, ich habe eine Waage</string>
+    <string name="wizard_step3_no">➡️  Nein, überspringen</string>
+
+    <!-- Gateway-Statusmeldungen -->
+    <string name="wizard_gateway_installed">Scale Gateway installiert ✅</string>
+    <string name="wizard_gateway_installed_detail">Wird beim Fortfahren im Hintergrund gestartet.</string>
+    <string name="wizard_gateway_not_installed">Scale Gateway nicht installiert</string>
+    <string name="wizard_gateway_not_installed_detail">Installiere die Scale Gateway App, um eine Bluetooth-Waage zu nutzen.</string>
+    <string name="wizard_gateway_checking">Prüfe auf Updates…</string>
+    <string name="wizard_gateway_up_to_date">Scale Gateway ist aktuell.</string>
+    <string name="wizard_gateway_update_available">Update für Scale Gateway verfügbar</string>
+    <string name="wizard_gateway_update_detail">Tippe auf den Button, um jetzt zu aktualisieren.</string>
+
+    <!-- Schaltflächen -->
+    <string name="btn_back">Zurück</string>
+    <string name="btn_launch">🚀  EverShelf starten</string>
+    <string name="btn_launch_no_scale">🚀  Ohne Waage starten</string>
+    <string name="btn_download_gateway">📥  Scale Gateway installieren</string>
+    <string name="btn_update_gateway">📥  Scale Gateway aktualisieren</string>
+</resources>

evershelf-kiosk/app/src/main/res/values-it/strings.xml

@@ -0,0 +1,28 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name">EverShelf Kiosk</string>
+
+    <!-- Wizard Step 3: Bilancia smart -->
+    <string name="wizard_step3_title">Bilancia Smart (Opzionale)</string>
+    <string name="wizard_step3_description">Per usare una bilancia da cucina Bluetooth, devi installare l\'app EverShelf Scale Gateway separatamente.</string>
+    <string name="wizard_step3_question">Hai una bilancia smart Bluetooth?</string>
+    <string name="wizard_step3_yes">✅  Sì, ho una bilancia</string>
+    <string name="wizard_step3_no">➡️  No, salta questo passaggio</string>
+
+    <!-- Messaggi stato gateway -->
+    <string name="wizard_gateway_installed">Scale Gateway installato ✅</string>
+    <string name="wizard_gateway_installed_detail">Verrà avviato in background quando procedi.</string>
+    <string name="wizard_gateway_not_installed">Scale Gateway non installato</string>
+    <string name="wizard_gateway_not_installed_detail">Installa l\'app Scale Gateway per usare una bilancia Bluetooth.</string>
+    <string name="wizard_gateway_checking">Controllo aggiornamenti…</string>
+    <string name="wizard_gateway_up_to_date">Scale Gateway è aggiornato.</string>
+    <string name="wizard_gateway_update_available">Aggiornamento disponibile per Scale Gateway</string>
+    <string name="wizard_gateway_update_detail">Tocca il pulsante qui sotto per aggiornarlo ora.</string>
+
+    <!-- Pulsanti -->
+    <string name="btn_back">Indietro</string>
+    <string name="btn_launch">🚀  Avvia EverShelf</string>
+    <string name="btn_launch_no_scale">🚀  Avvia senza bilancia</string>
+    <string name="btn_download_gateway">📥  Installa Scale Gateway</string>
+    <string name="btn_update_gateway">📥  Aggiorna Scale Gateway</string>
+</resources>

evershelf-kiosk/app/src/main/res/values/strings.xml

@@ -1,3 +1,27 @@
 <resources>
     <string name="app_name">EverShelf Kiosk</string>
+
+    <!-- Wizard Step 3: Smart scale -->
+    <string name="wizard_step3_title">Smart Scale (Optional)</string>
+    <string name="wizard_step3_description">To use a Bluetooth kitchen scale, you need the EverShelf Scale Gateway app installed separately.</string>
+    <string name="wizard_step3_question">Do you have a Bluetooth smart scale?</string>
+    <string name="wizard_step3_yes">✅  Yes, I have a scale</string>
+    <string name="wizard_step3_no">➡️  No, skip this step</string>
+
+    <!-- Gateway status messages -->
+    <string name="wizard_gateway_installed">Scale Gateway installed ✅</string>
+    <string name="wizard_gateway_installed_detail">Will be launched in the background when you proceed.</string>
+    <string name="wizard_gateway_not_installed">Scale Gateway not installed</string>
+    <string name="wizard_gateway_not_installed_detail">Install the Scale Gateway app to use a Bluetooth scale.</string>
+    <string name="wizard_gateway_checking">Checking for updates…</string>
+    <string name="wizard_gateway_up_to_date">Scale Gateway is up to date.</string>
+    <string name="wizard_gateway_update_available">Update available for Scale Gateway</string>
+    <string name="wizard_gateway_update_detail">Tap the button below to update it now.</string>
+
+    <!-- Buttons -->
+    <string name="btn_back">Back</string>
+    <string name="btn_launch">🚀  Launch EverShelf</string>
+    <string name="btn_launch_no_scale">🚀  Launch without scale</string>
+    <string name="btn_download_gateway">📥  Install Scale Gateway</string>
+    <string name="btn_update_gateway">📥  Update Scale Gateway</string>
 </resources>