allow sending broadcasts and cope with missing mesh services

app/src/main/aidl/com/geeksville/mesh/IMeshService.aidl

@@ -28,6 +28,8 @@ interface IMeshService {
     Send an opaque packet to a specified node name
 
     typ is defined in mesh.proto Data.Type.  For now juse use 0 to mean opaque bytes.
+
+    destId can be null to indicate "broadcast message"
     */
     void sendData(String destId, in byte[] payload, int typ);
 

app/src/main/java/com/geeksville/mesh/MainActivity.kt

@@ -80,6 +80,9 @@ eventually:
   make a custom theme: https://github.com/material-components/material-components-android/tree/master/material-theme-builder
 */
 
+val utf8 = Charset.forName("UTF-8")
+
+
 class MainActivity : AppCompatActivity(), Logging,
     ActivityCompat.OnRequestPermissionsResultCallback {
 
@@ -90,8 +93,6 @@ class MainActivity : AppCompatActivity(), Logging,
     }
 
 
-    private val utf8 = Charset.forName("UTF-8")
-
     private val bluetoothAdapter: BluetoothAdapter? by lazy(LazyThreadSafetyMode.NONE) {
         val bluetoothManager = getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
         bluetoothManager.adapter
@@ -154,12 +155,12 @@ class MainActivity : AppCompatActivity(), Logging,
     private fun setOwner() {
         // Note: we are careful to not set a new unique ID
         val name = UIState.ownerName.value
-        meshService!!.setOwner(null, name, getInitials(name))
+        UIState.meshService!!.setOwner(null, name, getInitials(name))
     }
 
     private fun sendTestPackets() {
         exceptionReporter {
-            val m = meshService!!
+            val m = UIState.meshService!!
 
             // Do some test operations
             val testPayload = "hello world".toByteArray()
@@ -270,7 +271,7 @@ class MainActivity : AppCompatActivity(), Logging,
 
     /// Read the config bytes from the radio so we can show them in our GUI, the radio's copy is ground truth
     private fun readRadioConfig() {
-        val bytes = meshService!!.radioConfig
+        val bytes = UIState.meshService!!.radioConfig
 
         val config = MeshProtos.RadioConfig.parseFrom(bytes)
         UIState.radioConfig.value = config
@@ -340,14 +341,13 @@ class MainActivity : AppCompatActivity(), Logging,
         }
     }
 
-    private var meshService: IMeshService? = null
     private var isBound = false
 
     private var serviceConnection = object : ServiceConnection {
         override fun onServiceConnected(name: ComponentName, service: IBinder) =
             exceptionReporter {
                 val m = IMeshService.Stub.asInterface(service)
-                meshService = m
+                UIState.meshService = m
 
                 // We don't start listening for packets until after we are connected to the service
                 registerMeshReceiver()
@@ -367,14 +367,14 @@ class MainActivity : AppCompatActivity(), Logging,
         override fun onServiceDisconnected(name: ComponentName) {
             warn("The mesh service has disconnected")
             unregisterMeshReceiver()
-            meshService = null
+            UIState.meshService = null
         }
     }
 
     private fun bindMeshService() {
         debug("Binding to mesh service!")
         // we bind using the well known name, to make sure 3rd party apps could also
-        logAssert(meshService == null)
+        logAssert(UIState.meshService == null)
 
         val intent = MeshService.startService(this)
         if (intent != null) {
@@ -391,7 +391,7 @@ class MainActivity : AppCompatActivity(), Logging,
         debug("Unbinding from mesh service!")
         if (isBound)
             unbindService(serviceConnection)
-        meshService = null
+        UIState.meshService = null
     }
 
     override fun onPause() {

app/src/main/java/com/geeksville/mesh/NodeInfo.kt

@@ -89,21 +89,22 @@ data class NodeInfo(
     }
 
     /// @return distance in meters to some other node (or null if unknown)
-    fun distance(o: NodeInfo?): Double? {
+    fun distance(o: NodeInfo?): Int? {
         val p = position
         val op = o?.position
         return if (p != null && op != null)
-            p.distance(op)
+            p.distance(op).toInt()
         else
             null
     }
 
     /// @return a nice human readable string for the distance, or null for unknown
     fun distanceStr(o: NodeInfo?) = distance(o)?.let { dist ->
-        if (dist < 1000)
-            "%.0f m".format(dist)
-        else
-            "%.1f km".format(dist / 1000)
+        when {
+            dist == 0 -> null // same point
+            dist < 1000 -> "%.0f m".format(dist)
+            else -> "%.1f km".format(dist / 1000.0)
+        }
     }
 
     override fun writeToParcel(parcel: Parcel, flags: Int) {

app/src/main/java/com/geeksville/mesh/model/MessagesState.kt

@@ -6,8 +6,15 @@ import java.util.*
 
 /**
  * the model object for a text message
+ *
+ * if errorMessage is set then we had a problem sending this message
  */
-data class TextMessage(val from: String, val text: String, val date: Date = Date())
+data class TextMessage(
+    val from: String,
+    val text: String,
+    val date: Date = Date(),
+    val errorMessage: String? = null
+)
 
 
 object MessagesState : Logging {

app/src/main/java/com/geeksville/mesh/model/UIState.kt

@@ -2,6 +2,7 @@ package com.geeksville.mesh.model
 
 import android.util.Base64
 import androidx.compose.mutableStateOf
+import com.geeksville.mesh.IMeshService
 import com.geeksville.mesh.MeshProtos
 
 /// FIXME - figure out how to merge this staate with the AppStatus Model
@@ -10,6 +11,7 @@ object UIState {
     /// Kinda ugly - created in the activity but used from Compose - figure out if there is a cleaner way GIXME
     // lateinit var googleSignInClient: GoogleSignInClient
 
+    var meshService: IMeshService? = null
 
     /// Are we connected to our radio device
     val isConnected = mutableStateOf(false)

app/src/main/java/com/geeksville/mesh/service/MeshService.kt

@@ -418,12 +418,21 @@ class MeshService : Service(), Logging {
         to = idNum
     }
 
-    /// Generate a new mesh packet builder with our node as the sender, and the specified recipient
-    private fun newMeshPacketTo(id: String) = newMeshPacketTo(toNodeNum(id))
+    /**
+     * Generate a new mesh packet builder with our node as the sender, and the specified recipient
+     *
+     * If id is null we assume a broadcast message
+     */
+    private fun newMeshPacketTo(id: String?) =
+        newMeshPacketTo(if (id != null) toNodeNum(id) else NODENUM_BROADCAST)
 
-    // Helper to make it easy to build a subpacket in the proper protobufs
+    /**
+     * Helper to make it easy to build a subpacket in the proper protobufs
+     *
+     * If destId is null we assume a broadcast message
+     */
     private fun buildMeshPacket(
-        destId: String,
+        destId: String?,
         initFn: MeshProtos.SubPacket.Builder.() -> Unit
     ): MeshPacket = newMeshPacketTo(destId).apply {
         payload = MeshProtos.SubPacket.newBuilder().also {
@@ -687,9 +696,9 @@ class MeshService : Service(), Logging {
                 connectedRadio.writeOwner(user.toByteArray())
             }
 
-        override fun sendData(destId: String, payloadIn: ByteArray, typ: Int) =
+        override fun sendData(destId: String?, payloadIn: ByteArray, typ: Int) =
             toRemoteExceptions {
-                info("sendData $destId <- ${payloadIn.size} bytes")
+                info("sendData dest=$destId <- ${payloadIn.size} bytes")
 
                 // encapsulate our payload in the proper protobufs and fire it off
                 val packet = buildMeshPacket(destId) {

app/src/main/java/com/geeksville/mesh/ui/Messages.kt

@@ -20,10 +20,13 @@ import androidx.ui.material.surface.Surface
 import androidx.ui.text.TextStyle
 import androidx.ui.tooling.preview.Preview
 import androidx.ui.unit.dp
+import com.geeksville.mesh.MeshProtos
 import com.geeksville.mesh.model.MessagesState
 import com.geeksville.mesh.model.MessagesState.messages
 import com.geeksville.mesh.model.NodeDB
 import com.geeksville.mesh.model.TextMessage
+import com.geeksville.mesh.model.UIState
+import com.geeksville.mesh.utf8
 import java.text.SimpleDateFormat
 
 
@@ -58,11 +61,11 @@ fun MessageCard(msg: TextMessage, modifier: Modifier = Modifier.None) {
                         style = MaterialTheme.typography().caption
                     )
                 }
-
             }
-            Text(
-                text = msg.text
-            )
+            if (msg.errorMessage != null)
+                Text(text = msg.errorMessage, style = TextStyle(color = palette.error))
+            else
+                Text(text = msg.text)
         }
     }
 }
@@ -109,10 +112,25 @@ fun MessagesContent() {
                 imeAction = ImeAction.Send,
                 onImeActionPerformed = {
                     MessagesState.info("did IME action")
+
+                    val str = message.value
+
+                    var error: String? = null
+                    val service = UIState.meshService
+                    if (service != null)
+                        service.sendData(
+                            null,
+                            str.toByteArray(utf8),
+                            MeshProtos.Data.Type.CLEAR_TEXT_VALUE
+                        )
+                    else
+                        error = "Error: No Mesh service"
+
                     MessagesState.addMessage(
                         TextMessage(
-                            "fixme",
-                            message.value
+                            NodeDB.myId.value,
+                            str,
+                            errorMessage = error
                         )
                     )
                 },

app/src/main/java/com/geeksville/mesh/ui/UserIcon.kt

@@ -5,8 +5,10 @@ import androidx.ui.core.Modifier
 import androidx.ui.core.Text
 import androidx.ui.layout.Column
 import androidx.ui.layout.LayoutGravity
+import androidx.ui.layout.LayoutWidth
 import androidx.ui.material.MaterialTheme
 import androidx.ui.tooling.preview.Preview
+import androidx.ui.unit.dp
 import com.geeksville.mesh.NodeInfo
 import com.geeksville.mesh.R
 import com.geeksville.mesh.model.NodeDB
@@ -14,10 +16,12 @@ import com.geeksville.mesh.model.NodeDB
 /**
  * Show the user icon for a particular user with distance from the operator and a small pointer
  * indicating their direction
+ *
+ * This component is fixed width to simplify layouts.
  */
 @Composable
 fun UserIcon(user: NodeInfo? = null, modifier: Modifier = Modifier.None) {
-    Column(modifier = modifier) {
+    Column(modifier = modifier + LayoutWidth(60.dp)) {
         VectorImage(
             id = R.drawable.ic_twotone_person_24,
             tint = palette.onSecondary,