Convert Arduino speedometer serial output to the Garmin TCX file for Strava

ArduinoSerialToGarminTcx.kt

data class RecordPoint(
        val speedMph: Int,
        val distanceIncrementMm: Int,
        val localTime: Date,
)

@Test
fun arduinoToTcx() {
    //----- CHANGE ME-------
    val startDay = "2021-03-10"
    //----------------------

    Locale.setDefault(Locale.ENGLISH)

    val dateFormat = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'")

    val inputFilePath = "C:\\Users\\spirit111\\Desktop\\input.txt"
    val outputFilePath = "C:\\Users\\spirit111\\Desktop\\output.tcx"

    val points = File(inputFilePath)
            .bufferedReader(Charsets.UTF_8)
            .readLines()
            .mapNotNull { line ->
                val split = line.split(';', ' ')
                        .takeIf { it.size == 3 }
                        ?: return@mapNotNull null

                RecordPoint(
                        localTime = dateFormat.parse(startDay + "T${split[0]}Z"),
                        speedMph = split.getOrNull(1)
                                ?.toIntOrNull()
                                ?: return@mapNotNull null,
                        distanceIncrementMm = split.getOrNull(2)
                                ?.toIntOrNull()
                                ?: return@mapNotNull null,
                )
            }

    File(outputFilePath).outputStream().bufferedWriter(Charsets.UTF_8).use {  writer ->
        writer.write("""
            <?xml version="1.0" encoding="UTF-8" standalone="no" ?>
            <TrainingCenterDatabase xmlns="http://www.garmin.com/xmlschemas/TrainingCenterDatabase/v2" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation
            ="http://www.garmin.com/xmlschemas/ActivityExtension/v2 http://www.garmin.com/xmlschemas/ActivityExtensionv2.xsd http://www.garmin.com/xmlschemas/TrainingCenterDat
            abase/v2 http://www.garmin.com/xmlschemas/TrainingCenterDatabasev2.xsd">

        """.trimIndent())

        val startTime = points.first().localTime

        writer.write(
                """
                    |   <Activities>
                    |       <Activity Sport="Biking">
                    |           <Id>42</Id>
                    |           <Lap StartTime="${dateFormat.format(startTime)}">
                    |
                """.trimMargin()
        )

        val totalTimeSeconds = (points.last().localTime.time - points.first().localTime.time) / 1000
        val totalDistanceMeters = points.sumBy { it.distanceIncrementMm } / 1000

        writer.write("""
            |               <TotalTimeSeconds>$totalTimeSeconds</TotalTimeSeconds>
            |               <DistanceMeters>$totalDistanceMeters</DistanceMeters>
            |               <TriggerMethod>Manual</TriggerMethod>
            |
        """.trimMargin())

        writer.write("""
            |                <Track>
            |
        """.trimMargin())

        var distanceMeters = 0.0

        points.forEach { point ->
            distanceMeters += point.distanceIncrementMm.toDouble() / 1000

            writer.write("""
                |                   <Trackpoint>
                |                       <Time>${dateFormat.format(point.localTime)}</Time>
                |                       <DistanceMeters>${"%.2f".format(distanceMeters)}</DistanceMeters>
                |                   </Trackpoint>
                |                   <Extensions>
                |                       <TPX xmlns="https://www8.garmin.com/xmlschemas/ActivityExtensionv2.xsd">
                |                           <Speed>${"%.2f".format(point.speedMph.toDouble() / 3600)}</Speed>
                |                       </TPX>
                |                   </Extensions>
                |
            """.trimMargin())
        }

        writer.write("""
            |                </Track>
            |            </Lap>
            |        </Activity>
            |    </Activities>
            |</TrainingCenterDatabase>
        """.trimMargin())
    }
}