Added custom frequency offset setting to network reporting

core/data/src/main/java/com/rtbishop/look4sat/core/data/framework/NetworkReporter.kt

@@ -17,8 +17,10 @@
  */
 package com.rtbishop.look4sat.core.data.framework
 
+import com.rtbishop.look4sat.core.domain.model.Constants
 import com.rtbishop.look4sat.core.domain.repository.IReporter
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.channels.Channel
 import kotlinx.coroutines.launch
 import kotlinx.coroutines.sync.Mutex
 import kotlinx.coroutines.sync.withLock
@@ -31,18 +33,30 @@ class NetworkReporter(
     private val rotatorServer: String,
     private val rotatorPort: Int,
     private val frequencyServer: String,
-    private val frequencyPort: Int
+    private val frequencyPort: Int,
+    private val frequencyOffsetHz: Long = 0L
 ) : IReporter {
 
     private val writeMutex = Mutex()
+    private val connectionMutex = Mutex()
+    private val frequencyCommands = Channel<String>(Channel.CONFLATED)
 
     private var rotatorSocket: SocketChannel? = null
     private var rotatorConnected = false
-    private var rotatorConnecting = false
 
     private var frequencySocket: SocketChannel? = null
     private var frequencyConnected = false
-    private var frequencyConnecting = false
+
+    init {
+        // Keep only the latest frequency command to avoid stale backlog and effective lag.
+        reporterScope.launch {
+            for (command in frequencyCommands) {
+                ensureFrequencyConnected()
+                if (!frequencyConnected) continue
+                write(frequencySocket, command) { resetFrequencyConnection() }
+            }
+        }
+    }
 
     override fun reportRotation(format: String, azimuth: Double, elevation: Double) {
         reporterScope.launch {
@@ -58,46 +72,43 @@ class NetworkReporter(
     }
 
     override fun reportFrequency(format: String, frequency: Long) {
-        reporterScope.launch {
-            ensureFrequencyConnected()
-            if (!frequencyConnected) return@launch
+        val clampedOffset = frequencyOffsetHz.coerceIn(
+            Constants.FREQ_OFFSET_MIN_HZ,
+            Constants.FREQ_OFFSET_MAX_HZ
+        )
+        val correctedFreq = frequency.coerceAtLeast(0L).safeAdd(clampedOffset).coerceAtLeast(0L)
         val command = format
-                .replace($$"$FREQ", frequency.toString())
+            .replace($$"$FREQ", correctedFreq.toString())
             .unescapeControlChars()
-            write(frequencySocket, command) { frequencyConnected = false }
-        }
+        frequencyCommands.trySend(command)
     }
 
-    private fun ensureRotatorConnected() {
-        if (rotatorConnected || rotatorConnecting || rotatorServer.isBlank()) return
-        reporterScope.launch {
+    private suspend fun ensureRotatorConnected() {
+        connectionMutex.withLock {
+            if (rotatorConnected || rotatorServer.isBlank()) return
             try {
-                rotatorConnecting = true
+                resetRotatorConnection()
                 rotatorSocket = SocketChannel.open(InetSocketAddress(rotatorServer, rotatorPort))
                 rotatorConnected = true
                 println("NetworkReporter: Rotator connected to $rotatorServer:$rotatorPort")
             } catch (e: Exception) {
                 println("NetworkReporter rotator connect error: ${e.message}")
-                rotatorConnected = false
-            } finally {
-                rotatorConnecting = false
+                resetRotatorConnection()
             }
         }
     }
 
-    private fun ensureFrequencyConnected() {
-        if (frequencyConnected || frequencyConnecting || frequencyServer.isBlank()) return
-        reporterScope.launch {
+    private suspend fun ensureFrequencyConnected() {
+        connectionMutex.withLock {
+            if (frequencyConnected || frequencyServer.isBlank()) return
             try {
-                frequencyConnecting = true
+                resetFrequencyConnection()
                 frequencySocket = SocketChannel.open(InetSocketAddress(frequencyServer, frequencyPort))
                 frequencyConnected = true
                 println("NetworkReporter: Frequency connected to $frequencyServer:$frequencyPort")
             } catch (e: Exception) {
                 println("NetworkReporter frequency connect error: ${e.message}")
-                frequencyConnected = false
-            } finally {
-                frequencyConnecting = false
+                resetFrequencyConnection()
             }
         }
     }
@@ -106,14 +117,42 @@ class NetworkReporter(
         try {
             writeMutex.withLock {
                 val buffer = ByteBuffer.wrap("$command\n".toByteArray())
+                while (buffer.hasRemaining()) {
                     socket?.write(buffer)
                 }
+            }
         } catch (e: Exception) {
             println("NetworkReporter write error: ${e.message}")
             onError()
         }
     }
 
+    private fun resetRotatorConnection() {
+        rotatorConnected = false
+        closeQuietly(rotatorSocket)
+        rotatorSocket = null
+    }
+
+    private fun resetFrequencyConnection() {
+        frequencyConnected = false
+        closeQuietly(frequencySocket)
+        frequencySocket = null
+    }
+
+    private fun closeQuietly(socket: SocketChannel?) {
+        try {
+            socket?.close()
+        } catch (_: Exception) {}
+    }
+
+    private fun Long.safeAdd(delta: Long): Long {
+        return when {
+            delta > 0 && this > Long.MAX_VALUE - delta -> Long.MAX_VALUE
+            delta < 0 && this < Long.MIN_VALUE - delta -> Long.MIN_VALUE
+            else -> this + delta
+        }
+    }
+
     private fun String.unescapeControlChars(): String =
         replace("\\r", "\r").replace("\\n", "\n").replace("\\t", "\t")
 }

core/data/src/main/java/com/rtbishop/look4sat/core/data/injection/MainContainer.kt

@@ -106,7 +106,8 @@ class MainContainer(private val context: Context) : IMainContainer {
             rc.rotatorAddress,
             rc.rotatorPort.toIntOrNull() ?: 0,
             rc.frequencyAddress,
-            rc.frequencyPort.toIntOrNull() ?: 0
+            rc.frequencyPort.toIntOrNull() ?: 0,
+            rc.frequencyOffsetHz
         )
     }
 

core/data/src/main/java/com/rtbishop/look4sat/core/data/repository/SettingsRepo.kt

@@ -29,6 +29,7 @@ import com.rtbishop.look4sat.core.domain.model.OtherSettings
 import com.rtbishop.look4sat.core.domain.model.PassesSettings
 import com.rtbishop.look4sat.core.domain.model.RCSettings
 import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.Constants
 import com.rtbishop.look4sat.core.domain.predict.GeoPos
 import com.rtbishop.look4sat.core.domain.repository.ISettingsRepo
 import com.rtbishop.look4sat.core.domain.source.Sources
@@ -69,6 +70,7 @@ class SettingsRepo(
     private val keyFrequencyAddress = "frequencyAddress"
     private val keyFrequencyPort = "frequencyPort"
     private val keyFrequencyFormat = "frequencyFormat"
+    private val keyFrequencyOffsetHz = "frequencyOffsetHz"
     private val keySelectedIds = "selectedIds"
     private val keySelectedSatModes = "selectedSatModes"
     private val keyStateOfAutoUpdate = "stateOfAutoUpdate"
@@ -277,6 +279,10 @@ class SettingsRepo(
     override val rcSettings: StateFlow<RCSettings> = _rcSettings
 
     override fun updateRCSettings(settings: RCSettings) {
+        val clampedFreqOffsetHz = settings.frequencyOffsetHz.coerceIn(
+            Constants.FREQ_OFFSET_MIN_HZ,
+            Constants.FREQ_OFFSET_MAX_HZ
+        )
         preferences.edit {
             putBoolean(keyRotatorState, settings.rotatorState)
             putString(keyRotatorAddress, settings.rotatorAddress)
@@ -286,6 +292,7 @@ class SettingsRepo(
             putString(keyFrequencyAddress, settings.frequencyAddress)
             putString(keyFrequencyPort, settings.frequencyPort)
             putString(keyFrequencyFormat, settings.frequencyFormat)
+            putLong(keyFrequencyOffsetHz, clampedFreqOffsetHz)
             putBoolean(keyBluetoothRotatorState, settings.bluetoothRotatorState)
             putString(keyBluetoothRotatorFormat, settings.bluetoothRotatorFormat)
             putString(keyBluetoothRotatorName, settings.bluetoothRotatorName)
@@ -294,7 +301,7 @@ class SettingsRepo(
             putString(keyBluetoothFrequencyFormat, settings.bluetoothFrequencyFormat)
             putString(keyBluetoothFrequencyAddress, settings.bluetoothFrequencyAddress)
         }
-        _rcSettings.value = settings
+        _rcSettings.value = settings.copy(frequencyOffsetHz = clampedFreqOffsetHz)
     }
 
     private fun getRCSettings(): RCSettings = RCSettings(
@@ -306,6 +313,8 @@ class SettingsRepo(
         frequencyAddress = preferences.getString(keyFrequencyAddress, null) ?: "127.0.0.1",
         frequencyPort = preferences.getString(keyFrequencyPort, null) ?: "4532",
         frequencyFormat = preferences.getString(keyFrequencyFormat, null) ?: $$"F $FREQ",
+        frequencyOffsetHz = preferences.getLong(keyFrequencyOffsetHz, 0L)
+            .coerceIn(Constants.FREQ_OFFSET_MIN_HZ, Constants.FREQ_OFFSET_MAX_HZ),
         bluetoothRotatorState = preferences.getBoolean(keyBluetoothRotatorState, false),
         bluetoothRotatorFormat = preferences.getString(keyBluetoothRotatorFormat, null) ?: $$"P $AZ $EL",
         bluetoothRotatorName = preferences.getString(keyBluetoothRotatorName, null) ?: "Default",
@@ -425,7 +434,7 @@ class SettingsRepo(
         val json = preferences.getString(keySatelliteOffsets, "{}") ?: "{}"
         return try {
             JSONObject(json).optString(catnum.toString(), "")
-        } catch (e: Exception) {
+        } catch (_: Exception) {
             ""
         }
     }
@@ -436,7 +445,7 @@ class SettingsRepo(
             val obj = JSONObject(json)
             if (offset.isEmpty()) obj.remove(catnum.toString()) else obj.put(catnum.toString(), offset)
             obj.toString()
-        } catch (e: Exception) {
+        } catch (_: Exception) {
             """{"$catnum": "$offset"}"""
         }
         preferences.edit { putString(keySatelliteOffsets, updated) }

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/DatabaseRepoTest.kt

@@ -120,6 +120,10 @@ private class FakeRemoteSource : IRemoteSource {
     override suspend fun getFileStream(uri: String): InputStream? = fileStreams[uri]?.invoke()
 
     override suspend fun getNetworkStream(url: String): InputStream? = networkStreams[url]?.invoke()
+
+    override suspend fun getAmSatCatalog(): String? = null
+
+    override suspend fun getAmSatReports(hours: Int, limit: Int): String? = null
 }
 
 private class FakeLocalSource : ILocalSource {
@@ -172,7 +176,7 @@ private class FakeSettingsRepo(dataSources: DataSourcesSettings = defaultDataSou
     override val databaseState: MutableStateFlow<DatabaseState> = MutableStateFlow(DatabaseState(0, 0, 0L))
 
     override val rcSettings: StateFlow<RCSettings> = MutableStateFlow(
-        RCSettings(false, "", "", "", false, "", "", "", false, "", "", "", false, "", "")
+        RCSettings(false, "", "", "", false, "", "", "", 0L, false, "", "", "", false, "", "")
     )
 
     override val otherSettings: StateFlow<OtherSettings> = MutableStateFlow(

core/data/src/test/java/com/rtbishop/look4sat/core/data/repository/SelectionRepoTest.kt

@@ -127,7 +127,7 @@ class SelectionRepoTest {
         override val databaseState: MutableStateFlow<DatabaseState> = MutableStateFlow(DatabaseState(0, 0, 0L))
 
         override val rcSettings: StateFlow<RCSettings> = MutableStateFlow(
-            RCSettings(false, "", "", "", false, "", "", "", false, "", "", "", false, "", "")
+            RCSettings(false, "", "", "", false, "", "", "", 0L, false, "", "", "", false, "", "")
         )
 
         override val otherSettings: StateFlow<OtherSettings> = MutableStateFlow(

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/Constants.kt

@@ -0,0 +1,23 @@
+/*
+ * Look4Sat. Amateur radio satellite tracker and pass predictor.
+ * Copyright (C) 2019-2026 Arty Bishop and contributors.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.rtbishop.look4sat.core.domain.model
+
+object Constants {
+    const val FREQ_OFFSET_MIN_HZ = -50_000L
+    const val FREQ_OFFSET_MAX_HZ = 50_000L
+}

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/model/Settings.kt

@@ -41,6 +41,7 @@ data class RCSettings(
     val frequencyAddress: String,
     val frequencyPort: String,
     val frequencyFormat: String,
+    val frequencyOffsetHz: Long = 0L,
     val bluetoothRotatorState: Boolean,
     val bluetoothRotatorFormat: String,
     val bluetoothRotatorName: String,

core/domain/src/main/java/com/rtbishop/look4sat/core/domain/utility/Extensions.kt

@@ -41,6 +41,21 @@ fun Double.round(decimals: Int): Double {
     return kotlin.math.round(this * multiplier) / multiplier
 }
 
+fun String.aprsPasscode(): Int {
+    val callsign = this.trim().uppercase().substringBefore('-') // commonly strip SSID
+    var hash = 0x73E2
+    var i = 0
+    while (i < callsign.length) {
+        hash = hash xor (callsign[i].code shl 8)
+        i++
+        if (i < callsign.length) {
+            hash = hash xor callsign[i].code
+            i++
+        }
+    }
+    return hash and 0x7FFF
+}
+
 //fun String.getHash(type: String = "SHA-256"): String {
 //    val hexChars = "0123456789ABCDEF"
 //    val bytes = MessageDigest.getInstance(type).digest(this.toByteArray())

core/domain/src/test/java/com/rtbishop/look4sat/core/domain/DataParserTest.kt

@@ -18,6 +18,7 @@
 package com.rtbishop.look4sat.core.domain
 
 import com.rtbishop.look4sat.core.domain.utility.DataParser
+import com.rtbishop.look4sat.core.domain.utility.aprsPasscode
 import kotlinx.coroutines.ExperimentalCoroutinesApi
 import kotlinx.coroutines.test.StandardTestDispatcher
 import kotlinx.coroutines.test.runTest
@@ -239,4 +240,10 @@ class DataParserTest {
         // Matches the CSV test data epoch: 2021-11-16 → day 320
         assert(dataParser.getDayOfYear(2021, 11, 16) == 320)
     }
+
+    @Test
+    fun `check APRS passcode calculation`() {
+        assert("M7LNB".aprsPasscode() == 12443)
+        assert("N0CALL".aprsPasscode() == 13023)
+    }
 }

core/presentation/src/main/res/values/strings.xml

@@ -196,6 +196,8 @@
     <string name="prefs_net_frequency_switch">Enable frequency output</string>
     <string name="prefs_net_frequency_address_hint">IP:Port</string>
     <string name="prefs_net_frequency_format_hint">Format</string>
+    <string name="prefs_net_frequency_offset_hint" translatable="false">Frequency offset (Hz)</string>
+    <string name="prefs_net_frequency_offset_help" translatable="false">Range: -50000 to 50000 Hz. Positive values increase reported frequency; negative values decrease it.</string>
 
     <string name="prefs_bt_title">Bluetooth output</string>
     <string name="prefs_bt_rotator_switch">Enable rotation output</string>

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/SettingsDialog.kt

@@ -39,6 +39,7 @@ import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedTextField
 import androidx.compose.material3.Switch
 import androidx.compose.material3.Text
+import androidx.compose.material3.TextButton
 import androidx.compose.runtime.Composable
 import androidx.compose.runtime.mutableIntStateOf
 import androidx.compose.runtime.mutableLongStateOf
@@ -58,6 +59,7 @@ import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import com.rtbishop.look4sat.core.domain.model.RCSettings
 import com.rtbishop.look4sat.core.domain.model.RadioControlSettings
+import com.rtbishop.look4sat.core.domain.model.Constants
 import com.rtbishop.look4sat.core.presentation.CardButton
 import com.rtbishop.look4sat.core.presentation.IconCard
 import com.rtbishop.look4sat.core.presentation.LocalSpacing
@@ -295,6 +297,7 @@ fun PreviewNetworkOutputDialog() {
                 frequencyAddress = "127.0.0.1",
                 frequencyPort = "4532",
                 frequencyFormat = $$"F $FREQ",
+                frequencyOffsetHz = 0L,
                 bluetoothRotatorState = false,
                 bluetoothRotatorFormat = $$"P $AZ $EL",
                 bluetoothRotatorName = "Default",
@@ -304,7 +307,7 @@ fun PreviewNetworkOutputDialog() {
                 bluetoothFrequencyFormat = $$"F $FREQ"
             ),
             onDismiss = {},
-            onSave = { _, _, _, _, _, _, _, _ -> }
+            onSave = { _, _, _, _, _, _, _, _, _ -> }
         )
     }
 }
@@ -315,7 +318,7 @@ fun NetworkOutputDialog(
     onDismiss: () -> Unit,
     onSave: (
         Boolean, String, String, String,
-        Boolean, String, String, String
+        Boolean, String, String, String, Long
     ) -> Unit
 ) {
     val padding = LocalSpacing.current.large
@@ -329,12 +332,15 @@ fun NetworkOutputDialog(
         mutableStateOf("${initialSettings.frequencyAddress}:${initialSettings.frequencyPort}")
     }
     val frequencyFormat = rememberSaveable { mutableStateOf(initialSettings.frequencyFormat) }
+    val frequencyOffsetHz = rememberSaveable { mutableStateOf(initialSettings.frequencyOffsetHz.toString()) }
     val onAccept = {
         val (rotIp, rotPort) = splitAddress(rotatorAddress.value)
         val (freqIp, freqPort) = splitAddress(frequencyAddress.value)
+        val offsetHz = (frequencyOffsetHz.value.trim().toLongOrNull() ?: 0L)
+            .coerceIn(Constants.FREQ_OFFSET_MIN_HZ, Constants.FREQ_OFFSET_MAX_HZ)
         onSave(
             rotatorState.value, rotIp, rotPort, rotatorFormat.value,
-            frequencyState.value, freqIp, freqPort, frequencyFormat.value
+            frequencyState.value, freqIp, freqPort, frequencyFormat.value, offsetHz
         )
         onDismiss()
     }
@@ -367,6 +373,27 @@ fun NetworkOutputDialog(
                 onFormatChange = { frequencyFormat.value = it },
                 formatLabel = stringResource(R.string.prefs_net_frequency_format_hint)
             )
+            Spacer(modifier = Modifier.height(6.dp))
+            OutlinedTextField(
+                value = frequencyOffsetHz.value,
+                onValueChange = { frequencyOffsetHz.value = it },
+                singleLine = true,
+                label = { Text(stringResource(R.string.prefs_net_frequency_offset_hint)) },
+                supportingText = { Text(stringResource(R.string.prefs_net_frequency_offset_help)) },
+                trailingIcon = {
+                    IconButton(
+                        onClick = { frequencyOffsetHz.value = "0" },
+                        enabled = frequencyState.value && frequencyOffsetHz.value != "0"
+                    ) {
+                        Icon(
+                            painter = painterResource(R.drawable.ic_close),
+                            contentDescription = null
+                        )
+                    }
+                },
+                modifier = Modifier.fillMaxWidth(),
+                enabled = frequencyState.value
+            )
             Spacer(modifier = Modifier.height(12.dp))
         }
     }
@@ -395,6 +422,7 @@ fun PreviewBluetoothOutputDialog() {
                 frequencyAddress = "127.0.0.1",
                 frequencyPort = "4532",
                 frequencyFormat = $$"F $FREQ",
+                frequencyOffsetHz = 0L,
                 bluetoothRotatorState = false,
                 bluetoothRotatorFormat = $$"P $AZ $EL",
                 bluetoothRotatorName = "Default",

feature/settings/src/main/java/com/rtbishop/look4sat/feature/settings/SettingsScreen.kt

@@ -134,14 +134,15 @@ private fun SettingsScreen(uiState: SettingsState, onAction: (SettingsAction) ->
         NetworkOutputDialog(
             initialSettings = uiState.rcSettings,
             onDismiss = { dialogs.network = false },
-            onSave = { rotState, rotAddr, rotPort, rotFmt, freqState, freqAddr, freqPort, freqFmt ->
+            onSave = { rotState, rotAddr, rotPort, rotFmt, freqState, freqAddr, freqPort, freqFmt, freqOffsetHz ->
                 onAction(
                     SettingsAction.UpdateRC(
                         uiState.rcSettings.copy(
                             rotatorState = rotState, rotatorAddress = rotAddr,
                             rotatorPort = rotPort, rotatorFormat = rotFmt,
                             frequencyState = freqState, frequencyAddress = freqAddr,
-                            frequencyPort = freqPort, frequencyFormat = freqFmt
+                            frequencyPort = freqPort, frequencyFormat = freqFmt,
+                            frequencyOffsetHz = freqOffsetHz
                         )
                     )
                 )