Removed all java dependencies from domain.predict package

app/src/main/java/com/rtbishop/look4sat/presentation/mapScreen/MapViewModel.kt

@@ -116,7 +116,7 @@ class MapViewModel @Inject constructor(
         val currentTrack = mutableListOf<GeoPos>()
         val endDate = Date(date.time + (satellite.orbitalPeriod * 2.4 * 60000L).toLong())
         var oldLongitude = 0.0
-        predictor.getSatTrack(satellite, pos, date, endDate).forEach { satPos ->
+        predictor.getSatTrack(satellite, pos, date.time, endDate.time).forEach { satPos ->
             val osmLat = clipLat(Math.toDegrees(satPos.latitude))
             val osmLon = clipLon(Math.toDegrees(satPos.longitude))
             val currentPosition = GeoPos(osmLat, osmLon)
@@ -143,7 +143,7 @@ class MapViewModel @Inject constructor(
     private suspend fun getPositions(satellites: List<Satellite>, pos: GeoPos, date: Date) {
         val positions = mutableMapOf<Satellite, GeoPos>()
         satellites.forEach { satellite ->
-            val satPos = predictor.getSatPos(satellite, pos, date)
+            val satPos = predictor.getSatPos(satellite, pos, date.time)
             val osmLat = clipLat(Math.toDegrees(satPos.latitude))
             val osmLon = clipLon(Math.toDegrees(satPos.longitude))
             positions[satellite] = GeoPos(osmLat, osmLon)
@@ -152,7 +152,7 @@ class MapViewModel @Inject constructor(
     }
 
     private suspend fun getSatFootprint(satellite: Satellite, pos: GeoPos, date: Date) {
-        val satPos = predictor.getSatPos(satellite, pos, date)
+        val satPos = predictor.getSatPos(satellite, pos, date.time)
         val satFootprint = satPos.getRangeCircle().map { rangePos ->
             val osmLat = clipLat(rangePos.latitude)
             val osmLon = clipLon(rangePos.longitude)
@@ -162,7 +162,7 @@ class MapViewModel @Inject constructor(
     }
 
     private suspend fun getSatData(satellite: Satellite, pos: GeoPos, date: Date) {
-        val satPos = predictor.getSatPos(satellite, pos, date)
+        val satPos = predictor.getSatPos(satellite, pos, date.time)
         val osmLat = clipLat(Math.toDegrees(satPos.latitude))
         val osmLon = clipLon(Math.toDegrees(satPos.longitude))
         val osmPos = GeoPos(osmLat, osmLon)

app/src/main/java/com/rtbishop/look4sat/presentation/passesScreen/PassesViewModel.kt

@@ -49,12 +49,12 @@ class PassesViewModel @Inject constructor(
         if (preferences.isSetupDone()) {
             viewModelScope.launch {
                 _passes.postValue(DataState.Loading)
-                val dateNow = Date()
+                val timeNow = System.currentTimeMillis()
                 val satellites = dataRepository.getSelectedSatellites()
                 val stationPos = preferences.loadStationPosition()
                 val hoursAhead = preferences.getHoursAhead()
                 val minElev = preferences.getMinElevation()
-                predictor.triggerCalculation(satellites, stationPos, dateNow, hoursAhead, minElev)
+                predictor.triggerCalculation(satellites, stationPos, timeNow, hoursAhead, minElev)
             }
         } else {
             _isFirstLaunchDone.value = false
@@ -77,7 +77,7 @@ class PassesViewModel @Inject constructor(
             val minElev = preferences.getMinElevation()
             dataRepository.updateDataFromWeb()
             dataRepository.updateSelection(isSelected = true)
-            predictor.forceCalculation(satellites, stationPos, Date(), hoursAhead, minElev)
+            predictor.forceCalculation(satellites, stationPos, Date().time, hoursAhead, minElev)
             preferences.setSetupDone()
             _isFirstLaunchDone.value = true
         }
@@ -87,12 +87,12 @@ class PassesViewModel @Inject constructor(
         viewModelScope.launch {
             _passes.postValue(DataState.Loading)
             passesProcessing?.cancelAndJoin()
-            val dateNow = Date()
+            val timeNow = System.currentTimeMillis()
             val satellites = dataRepository.getSelectedSatellites()
             val stationPos = preferences.loadStationPosition()
             val hoursAhead = preferences.getHoursAhead()
             val minElev = preferences.getMinElevation()
-            predictor.forceCalculation(satellites, stationPos, dateNow, hoursAhead, minElev)
+            predictor.forceCalculation(satellites, stationPos, timeNow, hoursAhead, minElev)
         }
     }
 

app/src/main/java/com/rtbishop/look4sat/presentation/radarScreen/RadarViewModel.kt

@@ -79,12 +79,12 @@ class RadarViewModel @Inject constructor(
         viewModelScope.launch {
             var satTrack: List<SatPos> = emptyList()
             if (!satPass.isDeepSpace) {
-                val startDate = Date(satPass.aosTime)
+                val startDate = satPass.aosTime
-                val endDate = Date(satPass.losTime)
+                val endDate = satPass.losTime
                 satTrack = predictor.getSatTrack(satPass.satellite, stationPos, startDate, endDate)
             }
             while (isActive) {
-                val satPos = predictor.getSatPos(satPass.satellite, stationPos, Date())
+                val satPos = predictor.getSatPos(satPass.satellite, stationPos, Date().time)
                 if (preferences.isRotatorEnabled()) {
                     val server = preferences.getRotatorServer().first
                     val port = preferences.getRotatorServer().second
@@ -102,7 +102,7 @@ class RadarViewModel @Inject constructor(
         viewModelScope.launch {
             val transmitters = dataRepository.getTransmitters(satPass.catNum)
             while (isActive) {
-                val satPos = predictor.getSatPos(satPass.satellite, stationPos, Date())
+                val satPos = predictor.getSatPos(satPass.satellite, stationPos, Date().time)
                 val copiedList = transmitters.map { it.copy() }
                 copiedList.forEach { transmitter ->
                     transmitter.downlink?.let {

core/src/main/java/com/rtbishop/look4sat/domain/predict/Predictor.kt

@@ -21,7 +21,6 @@ import kotlinx.coroutines.CoroutineDispatcher
 import kotlinx.coroutines.flow.MutableSharedFlow
 import kotlinx.coroutines.flow.SharedFlow
 import kotlinx.coroutines.withContext
-import java.util.*
 
 class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
 
@@ -29,26 +28,26 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
     private var selectedSatIds = emptyList<Int>()
     val passes: SharedFlow<List<SatPass>> = _passes
 
-    suspend fun getSatPos(sat: Satellite, pos: GeoPos, date: Date): SatPos =
+    suspend fun getSatPos(sat: Satellite, pos: GeoPos, time: Long): SatPos {
-        withContext(predictorDispatcher) {
+        return withContext(predictorDispatcher) { sat.getPosition(pos, time) }
-            return@withContext sat.getPosition(pos, date.time)
+    }
-        }
 
-    suspend fun getSatTrack(sat: Satellite, pos: GeoPos, start: Date, end: Date): List<SatPos> =
+    suspend fun getSatTrack(sat: Satellite, pos: GeoPos, start: Long, end: Long): List<SatPos> {
-        withContext(predictorDispatcher) {
+        return withContext(predictorDispatcher) {
             val positions = mutableListOf<SatPos>()
-            var currentTime = start.time
+            var currentTime = start
-            while (currentTime < end.time) {
+            while (currentTime < end) {
                 positions.add(sat.getPosition(pos, currentTime))
                 currentTime += 15000
             }
-            return@withContext positions
+            positions
         }
+    }
 
     suspend fun triggerCalculation(
         satellites: List<Satellite>,
         pos: GeoPos,
-        date: Date = Date(),
+        time: Long,
         hoursAhead: Int = 8,
         minElevation: Double = 16.0
     ) {
@@ -57,7 +56,7 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
         } else {
             val newCatNums = satellites.map { it.params.catnum }
             if (selectedSatIds != newCatNums) {
-                forceCalculation(satellites, pos, date, hoursAhead, minElevation)
+                forceCalculation(satellites, pos, time, hoursAhead, minElevation)
             }
         }
     }
@@ -65,7 +64,7 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
     suspend fun forceCalculation(
         satellites: List<Satellite>,
         pos: GeoPos,
-        date: Date = Date(),
+        time: Long,
         hoursAhead: Int = 8,
         minElevation: Double = 16.0
     ) {
@@ -76,31 +75,31 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
                 val allPasses = mutableListOf<SatPass>()
                 selectedSatIds = satellites.map { it.params.catnum }
                 satellites.forEach { satellite ->
-                    allPasses.addAll(satellite.getPasses(pos, date, hoursAhead))
+                    allPasses.addAll(satellite.getPasses(pos, time, hoursAhead))
                 }
-                _passes.emit(allPasses.filter(date, hoursAhead, minElevation))
+                _passes.emit(allPasses.filter(time, hoursAhead, minElevation))
             }
         }
     }
 
-    private fun Satellite.getPasses(pos: GeoPos, date: Date, hours: Int): List<SatPass> {
+    private fun Satellite.getPasses(pos: GeoPos, time: Long, hours: Int): List<SatPass> {
         val passes = mutableListOf<SatPass>()
-        val endDate = Date(date.time + hours * 60L * 60L * 1000L)
+        val endDate = time + hours * 60L * 60L * 1000L
         val quarterOrbitMin = (this.orbitalPeriod / 4.0).toInt()
-        var startDate = date
+        var startDate = time
         var shouldRewind = true
-        var lastAosDate: Date
+        var lastAosDate: Long
         var count = 0
         if (this.willBeSeen(pos)) {
             if (this.params.isDeepspace) {
-                passes.add(getGeoPass(this, pos, date))
+                passes.add(getGeoPass(this, pos, time))
             } else {
                 do {
                     if (count > 0) shouldRewind = false
                     val pass = getLeoPass(this, pos, startDate, shouldRewind)
-                    lastAosDate = Date(pass.aosTime)
+                    lastAosDate = pass.aosTime
                     passes.add(pass)
-                    startDate = Date(pass.losTime + (quarterOrbitMin * 3) * 60L * 1000L)
+                    startDate = pass.losTime + (quarterOrbitMin * 3) * 60L * 1000L
                     count++
                 } while (lastAosDate < endDate)
             }
@@ -108,53 +107,50 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
         return passes
     }
 
-    private fun List<SatPass>.filter(date: Date, hoursAhead: Int, minElev: Double): List<SatPass> {
+    private fun List<SatPass>.filter(time: Long, hoursAhead: Int, minElev: Double): List<SatPass> {
-        val timeFuture = date.time + (hoursAhead * 60L * 60L * 1000L)
+        val timeFuture = time + (hoursAhead * 60L * 60L * 1000L)
-        return this.filter { it.losTime > date.time }
+        return this.filter { it.losTime > time }
             .filter { it.aosTime < timeFuture }
             .filter { it.maxElevation > minElev }
             .sortedBy { it.aosTime }
     }
 
-    private fun getGeoPass(sat: Satellite, pos: GeoPos, date: Date): SatPass {
+    private fun getGeoPass(sat: Satellite, pos: GeoPos, time: Long): SatPass {
-        val satPos = sat.getPosition(pos, date.time)
+        val satPos = sat.getPosition(pos, time)
-        val aos = Date(date.time - 24 * 60L * 60L * 1000L).time
+        val aos = time - 24 * 60L * 60L * 1000L
-        val los = Date(date.time + 24 * 60L * 60L * 1000L).time
+        val los = time + 24 * 60L * 60L * 1000L
-        val tca = Date((aos + los) / 2).time
+        val tca = (aos + los) / 2
         val az = Math.toDegrees(satPos.azimuth)
         val elev = Math.toDegrees(satPos.elevation)
         val alt = satPos.altitude
         return SatPass(aos, az, los, az, tca, az, alt, elev, sat)
     }
 
-    private fun getLeoPass(sat: Satellite, pos: GeoPos, date: Date, rewind: Boolean): SatPass {
+    private fun getLeoPass(sat: Satellite, pos: GeoPos, time: Long, rewind: Boolean): SatPass {
         val quarterOrbitMin = (sat.orbitalPeriod / 4.0).toInt()
-        val calendar = Calendar.getInstance(TimeZone.getTimeZone("UTC")).apply {
+        var calendarTimeMillis = time
-            clear()
-            timeInMillis = date.time
-        }
         var elevation: Double
         var maxElevation = 0.0
         var alt = 0.0
         var tcaAz = 0.0
         // rewind 1/4 of an orbit
-        if (rewind) calendar.add(Calendar.MINUTE, -quarterOrbitMin)
+        if (rewind) calendarTimeMillis += -quarterOrbitMin * 60L * 1000L
 
-        var satPos = sat.getPosition(pos, calendar.time.time)
+        var satPos = sat.getPosition(pos, calendarTimeMillis)
         if (satPos.elevation > 0.0) {
             // move forward in 30 second intervals until the sat goes below the horizon
             do {
-                calendar.add(Calendar.SECOND, 30)
+                calendarTimeMillis += 30 * 1000L
-                satPos = sat.getPosition(pos, calendar.time.time)
+                satPos = sat.getPosition(pos, calendarTimeMillis)
             } while (satPos.elevation > 0.0)
             // move forward 3/4 of an orbit
-            calendar.add(Calendar.MINUTE, quarterOrbitMin * 3)
+            calendarTimeMillis += quarterOrbitMin * 3 * 60L * 1000L
         }
 
         // find the next time sat comes above the horizon
         do {
-            calendar.add(Calendar.SECOND, 60)
+            calendarTimeMillis += 60L * 1000L
-            satPos = sat.getPosition(pos, calendar.time.time)
+            satPos = sat.getPosition(pos, calendarTimeMillis)
             elevation = satPos.elevation
             if (elevation > maxElevation) {
                 maxElevation = elevation
@@ -164,10 +160,10 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
         } while (satPos.elevation < 0.0)
 
         // refine to 3 seconds
-        calendar.add(Calendar.SECOND, -60)
+        calendarTimeMillis += -60L * 1000L
         do {
-            calendar.add(Calendar.SECOND, 3)
+            calendarTimeMillis += 3L * 1000L
-            satPos = sat.getPosition(pos, calendar.time.time)
+            satPos = sat.getPosition(pos, calendarTimeMillis)
             elevation = satPos.elevation
             if (elevation > maxElevation) {
                 maxElevation = elevation
@@ -181,8 +177,8 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
 
         // find when sat goes below
         do {
-            calendar.add(Calendar.SECOND, 30)
+            calendarTimeMillis += 30L * 1000L
-            satPos = sat.getPosition(pos, calendar.time.time)
+            satPos = sat.getPosition(pos, calendarTimeMillis)
             elevation = satPos.elevation
             if (elevation > maxElevation) {
                 maxElevation = elevation
@@ -192,10 +188,10 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
         } while (satPos.elevation > 0.0)
 
         // refine to 3 seconds
-        calendar.add(Calendar.SECOND, -30)
+        calendarTimeMillis += -30L * 1000L
         do {
-            calendar.add(Calendar.SECOND, 3)
+            calendarTimeMillis += 3L * 1000L
-            satPos = sat.getPosition(pos, calendar.time.time)
+            satPos = sat.getPosition(pos, calendarTimeMillis)
             elevation = satPos.elevation
             if (elevation > maxElevation) {
                 maxElevation = elevation
@@ -206,7 +202,7 @@ class Predictor(private val predictorDispatcher: CoroutineDispatcher) {
 
         val los = satPos.time
         val losAz = Math.toDegrees(satPos.azimuth)
-        val tca = Date((aos + los) / 2).time
+        val tca = (aos + los) / 2
         val elev = Math.toDegrees(maxElevation)
         return SatPass(aos, aosAz, los, losAz, tca, tcaAz, alt, elev, sat)
     }

core/src/main/java/com/rtbishop/look4sat/domain/predict/Satellite.kt

@@ -17,8 +17,6 @@
  */
 package com.rtbishop.look4sat.domain.predict
 
-import java.util.*
-import java.util.concurrent.atomic.AtomicReference
 import kotlin.math.*
 
 abstract class Satellite(val params: TLE) {
@@ -30,6 +28,7 @@ abstract class Satellite(val params: TLE) {
     private val epsilon = 1.0E-12
     private val position = Vector4()
     private val velocity = Vector4()
+    private var gsPosTheta = 0.0
     private var perigee = 0.0
     val orbitalPeriod = 24 * 60 / params.meanmo
     val earthRadius = 6378.137
@@ -74,10 +73,7 @@ abstract class Satellite(val params: TLE) {
 
     // Read the system clock and return the number of days since 31Dec79 00:00:00 UTC (daynum 0)
     private fun calcCurrentDaynum(now: Long): Double {
-        val sgp4Epoch = Calendar.getInstance(TimeZone.getTimeZone("UTC:UTC"))
+        val then = 315446400000 // time in millis on 31Dec79 00:00:00 UTC (daynum 0)
-        sgp4Epoch.clear()
-        sgp4Epoch[1979, 11, 31, 0, 0] = 0
-        val then = sgp4Epoch.timeInMillis
         val millis = now - then
         return millis / 1000.0 / 60.0 / 60.0 / 24.0
     }
@@ -124,8 +120,7 @@ abstract class Satellite(val params: TLE) {
         val obsVel = Vector4()
         val range = Vector4()
         val rgvel = Vector4()
-        val gsPosTheta = AtomicReference<Double>()
+        calculateUserPosVel(julianUTC, gsPos, obsPos, obsVel)
-        calculateUserPosVel(julianUTC, gsPos, gsPosTheta, obsPos, obsVel)
         range.setXYZ(
             positionVector.x - obsPos.x,
             positionVector.y - obsPos.y,
@@ -141,8 +136,8 @@ abstract class Satellite(val params: TLE) {
         magnitude(range)
         val sinLat = sin(deg2Rad * gsPos.latitude)
         val cosLat = cos(deg2Rad * gsPos.latitude)
-        val sinTheta = sin(gsPosTheta.get())
+        val sinTheta = sin(gsPosTheta)
-        val cosTheta = cos(gsPosTheta.get())
+        val cosTheta = cos(gsPosTheta)
         val topS = sinLat * cosTheta * range.x + sinLat * sinTheta * range.y - cosLat * range.z
         val topE = -sinTheta * range.x + cosTheta * range.y
         val topZ = cosLat * cosTheta * range.x + cosLat * sinTheta * range.y + sinLat * range.z
@@ -159,18 +154,17 @@ abstract class Satellite(val params: TLE) {
     private fun calculateUserPosVel(
         time: Double,
         gsPos: GeoPos,
-        gsPosTheta: AtomicReference<Double>,
         obsPos: Vector4,
         obsVel: Vector4
     ) {
         val mFactor = 7.292115E-5
-        gsPosTheta.set(mod2PI(thetaGJD(time) + deg2Rad * gsPos.longitude))
+        gsPosTheta = mod2PI(thetaGJD(time) + deg2Rad * gsPos.longitude)
         val c =
             invert(sqrt(1.0 + flatFactor * (flatFactor - 2) * sqr(sin(deg2Rad * gsPos.latitude))))
         val sq = sqr(1.0 - flatFactor) * c
         val achcp = (earthRadius * c) * cos(deg2Rad * gsPos.latitude)
         obsPos.setXYZ(
-            achcp * cos(gsPosTheta.get()), achcp * sin(gsPosTheta.get()),
+            achcp * cos(gsPosTheta), achcp * sin(gsPosTheta),
             (earthRadius * sq) * sin(deg2Rad * gsPos.latitude)
         )
         obsVel.setXYZ(-mFactor * obsPos.y, mFactor * obsPos.x, 0.0)