ModemConfig: Add a simple notification showing to-be-flashed firmware

In order to help our efforts finalizing the initial release, provide a
little bit of info to the user about the detected config and the
firmware path belonging to the installation.

TODO: This can be improved in various ways:
- Clear sony.modemswitcher.modem_name_*, and wait for it to change.
  This variable contains the path so that we do not need to read it from
  a file, including the default path (when the config is not found).
- Extend the notification (or start a Dialog/Activity onclick) to
  display more diagnostic info.

Signed-off-by: Marijn Suijten <marijns95@gmail.com>

ModemConfig/AndroidManifest.xml

@@ -7,6 +7,7 @@
 
     <application
         android:directBootAware="true"
+        android:label="@string/app_name"
         android:persistent="true">
         <receiver
             android:name=".BootReceiver"

ModemConfig/res/drawable/ic_sim_card.xml

@@ -0,0 +1,24 @@
+<?xml version="1.0" encoding="UTF-8"?><!--
+  ~ Copyright (C) 2020 The Android Open Source Project
+  ~
+  ~ Licensed under the Apache License, Version 2.0 (the "License");
+  ~ you may not use this file except in compliance with the License.
+  ~ You may obtain a copy of the License at
+  ~
+  ~      http://www.apache.org/licenses/LICENSE-2.0
+  ~
+  ~ Unless required by applicable law or agreed to in writing, software
+  ~ distributed under the License is distributed on an "AS IS" BASIS,
+  ~ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  ~ See the License for the specific language governing permissions and
+  ~ limitations under the License
+  -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="24dp"
+    android:height="24dp"
+    android:viewportHeight="24"
+    android:viewportWidth="24">
+    <path
+        android:fillColor="#757575"
+        android:pathData="M19.99 4c0-1.1-.89-2-1.99-2h-8L4 8v12c0 1.1.9 2 2 2h12.01c1.1 0 1.99-.9 1.99-2l-.01-16zM9 19H7v-2h2v2zm8 0h-2v-2h2v2zm-8-4H7v-4h2v4zm4 4h-2v-4h2v4zm0-6h-2v-2h2v2zm4 2h-2v-4h2v4z" />
+</vector>

ModemConfig/res/values-de/strings.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="notification_channel_configuration_info">Konfigurationsinfo</string>
+
+    <string name="notification_title_modem_configuration">Modem-Konfiguration</string>
+    <string name="notification_text_modem_configuration_resolved_modem_config">Benutze Modem-Konfiguration: %1$s\nFirmware-Datei: %2$s</string>
+    <string name="notification_text_modem_configuration_no_match">Keine passende Modem-Konfiguration gefunden</string>
+</resources>

ModemConfig/res/values-fr/strings.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="notification_channel_configuration_info">Informations de configuration</string>
+
+    <string name="notification_title_modem_configuration">Configuration du modem</string>
+    <string name="notification_text_modem_configuration_resolved_modem_config">Configuration du modem utilisée : %1$s\nFirmware utilisé: %2$s</string>
+    <string name="notification_text_modem_configuration_no_match">Aucune configuration de modem trouvée </string>
+</resources>

ModemConfig/res/values-it/strings.xml

@@ -0,0 +1,8 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="notification_channel_configuration_info">Informazioni configurazione</string>
+
+    <string name="notification_title_modem_configuration">Configurazione Modem</string>
+    <string name="notification_text_modem_configuration_resolved_modem_config">Uso configurazione modem %1$s\nFile firmware: %2%$s</string>
+    <string name="notification_text_modem_configuration_no_match">Nessuna configurazione modem trovata</string>
+</resources>

ModemConfig/res/values/strings.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <string name="app_name" translatable="false">ModemConfig</string>
+
+    <string name="modem_config_path" translatable="false">/oem/modem-config</string>
+    <string name="modem_config_name" translatable="false">modem.conf</string>
+
+    <string name="notification_channel_configuration_info">Configuration info</string>
+
+    <string name="notification_title_modem_configuration">Modem configuration</string>
+    <string name="notification_text_modem_configuration_resolved_modem_config">Using modem configuration: %1$s\nFirmware file: %2$s</string>
+    <string name="notification_text_modem_configuration_no_match">Found no modem configuration</string>
+</resources>

ModemConfig/src/com/sony/opentelephony/modemconfig/ModemConfigService.kt

@@ -16,6 +16,9 @@
 
 package com.sony.opentelephony.modemconfig
 
+import android.app.Notification
+import android.app.NotificationChannel
+import android.app.NotificationManager
 import android.app.Service
 import android.content.Context
 import android.content.Intent
@@ -27,9 +30,14 @@ import android.telephony.TelephonyManager
 import android.text.TextUtils
 import android.util.Log
 import org.xmlpull.v1.XmlPullParser
+import java.nio.file.Files
+import java.nio.file.Paths
 
 private const val TAG = "ModemConfigReceiver"
 private const val VERBOSE = false
+private const val NOTIFICATION_CHANNEL_ID = "Configuration"
+private const val NOTIFICATION_ID = 1
+
 private val newlineMatch = Regex("[\n\r]")
 
 class ModemConfigService : Service() {
@@ -49,6 +57,11 @@ class ModemConfigService : Service() {
     // TODO: Do a lateinit here?
     private /*lateinit*/ var providers: List<ProviderFilter>? = null
 
+    private val notificationManager: NotificationManager by lazy {
+        getSystemService(NotificationManager::class.java)
+        ?: throw Exception("Expected NotificationManager, got null")
+    }
+
     private fun getProviders(context: Context): List<ProviderFilter> {
         if (providers != null)
             return providers!!
@@ -155,6 +168,21 @@ context.resources.getXml(R.xml.service_provider_sim_configs).use {
         }
     }
 
+    private fun findFirmwarePath(configId: String): String {
+        val conf = Paths.get(resources.getString(R.string.modem_config_path), configId,
+                             resources.getString(R.string.modem_config_name))
+        return try {
+            if (Files.isRegularFile(conf)) {
+                Files.readAllLines(conf).first()
+            } else {
+                // TODO: Can/should we read default from modem-switcher prop?
+                "default"
+            }
+        } catch (e: Exception) {
+            "failed to derive"
+        }
+    }
+
     private fun handleSubscription(sub: SubscriptionInfo) {
         if (VERBOSE) Log.v(TAG, "Checking sub $sub")
 
@@ -162,11 +190,28 @@ context.resources.getXml(R.xml.service_provider_sim_configs).use {
         val tm = globalTm!!.createForSubscriptionId(sub.subscriptionId)
         val name = findConfigurationName(this, tm)
 
-        if (name != null) {
+        val notificationText = if (name != null) {
             val prop = "persist.vendor.somc.cust.modem${sub.simSlotIndex}"
             if (VERBOSE) Log.v(TAG, "Setting $prop to $name")
             SystemProperties.set(prop, name)
+
+            resources.getString(
+                    R.string.notification_text_modem_configuration_resolved_modem_config,
+                    name,
+                    findFirmwarePath(name))
+        } else {
+            resources.getString(R.string.notification_text_modem_configuration_no_match)
         }
+
+        val notification = Notification.Builder(this, NOTIFICATION_CHANNEL_ID).run {
+            setSmallIcon(R.drawable.ic_sim_card)
+            setContentTitle(resources.getString(R.string.notification_title_modem_configuration))
+            setContentText(notificationText.substringBefore('\n'))
+            style = Notification.BigTextStyle().bigText(notificationText)
+            build()
+        }
+
+        notificationManager.notify(NOTIFICATION_ID, notification)
     }
 
     override fun onCreate() {
@@ -174,6 +219,12 @@ context.resources.getXml(R.xml.service_provider_sim_configs).use {
         val sm = getSystemService(SubscriptionManager::class.java)
                  ?: throw Exception("Expected SubscriptionManager, got null")
 
+        val channel = NotificationChannel(
+                NOTIFICATION_CHANNEL_ID,
+                resources.getString(R.string.notification_channel_configuration_info),
+                NotificationManager.IMPORTANCE_LOW)
+        notificationManager.createNotificationChannel(channel)
+
         // Our callback is invoked once on .add too; no need to run the contents manually at startup
         sm.addOnSubscriptionsChangedListener(
                 object : SubscriptionManager.OnSubscriptionsChangedListener() {