如何在 Android 上取得準確且不被用戶竄改的時間

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import android.os.Build
import android.os.SystemClock

import java.time.ZoneId
import java.time.ZonedDateTime
import java.time.format.DateTimeFormatter


fun getGpsApiDateTime(): String {
    return if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.Q) {
        try {
            val zoneClock =
                SystemClock.currentGnssTimeClock().withZone(ZoneId.of("Asia/Taipei"))
            ZonedDateTime.now(zoneClock).format(dateTimeFormatter)
        } catch (e: Exception) {
            "GNSS NOT AVAILABLE"
        }
    } else {
        "SYSTEM NOT AVAILABLE"
    }
}

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class RealTimeApp : Application() {

    override fun onCreate() {
        super.onCreate()

        // ...
        initTrueTime()
    }

    private fun initTrueTime() {
        val trueTime: TrueTimeImpl by inject()
        trueTime.sync()
    }
}

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import com.instacart.truetime.time.TrueTime

import java.time.Instant
import java.time.ZoneId
import java.time.ZonedDateTime
import java.time.format.DateTimeFormatter


fun getNtpDateTime(): String {
    return ZonedDateTime.ofInstant(
        trueTime.now().toInstant(),
        zoneId
    ).format(dateTimeFormatter)
}

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locationManager.requestLocationUpdates(
    provider,
    minTimeMs = 500L,
    minDistanceM = 0f,
    locationListener,
)

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$GNRMC,040404.00,A,2410.982071,N,12037.531786,E,0.0,,030824,3.0,W,A,V*6C

$GPRMC,220516,A,5133.82,N,00042.24,W,173.8,231.8,130694,004.2,W*70
        1    2    3    4    5     6    7    8      9     10  11 12


1   220516     Time Stamp (hhmmss.ss)
2   A          validity - A-ok, V-invalid
3   5133.82    current Latitude
4   N          North/South
5   00042.24   current Longitude
6   W          East/West
7   173.8      Speed in knots
8   231.8      True course
9   130694     Date Stamp (ddmmyy)
10  004.2      Variation
11  W          East/West
12  *70        checksum

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locationManager.addNmeaListener(object : OnNmeaMessageListener {
    override fun onNmeaMessage(message: String?, timestamp: Long) {
        if (message == null) return
        
        if (message.contains("RMC")) {
            Log.d(TAG, "onNmeaMessage: $message")
            val rmcTimeInMillis = parseRmcEpochMillis(message)
            if (rmcTimeInMillis == -1L) {
                Log.d(TAG,"No RMC Data Found")
            } else {
                Log.d(TAG,formatDateTime(rmcTimeInMillis))
            }
        }
    }
    
}, null)

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private fun parseRmcEpochMillis(message: String): Long {
    val splits = message.split(",")
    if (splits.size < 12) return -1
    
    val time = splits[1]
    val isDataValid =  splits[2] == "A"
    val date = splits[9]
    
    Log.d(TAG, "onNmeaMessage: IsDataValid = $isDataValid / $date /$time")
    
    if (!isDataValid) return -1
    
    return try {
        val dateTime = LocalDateTime.parse(
            "$date-${time.substring(0, 6)}",
            DateTimeFormatter.ofPattern("ddMMyy-HHmmss")
        )
        val instant = dateTime.toInstant(ZoneOffset.UTC)
        val epochSecond = instant.atZone(ZoneId.of("Asia/Taipei")).toEpochSecond()
        Log.d(TAG, "parseRmcEpochSecond: $epochSecond")
        epochSecond * 1000L
    } catch (e: Exception) {
        Log.e(TAG, "parseRmcTime: ", e)
        -1
    }
}

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long gpsTime = location.getTime();

// Adding 1024 weeks to fix Week Number Rollover issue for old GPS chips
// 619315200000L = 1024 * 7 * 24 * 60 * 60 * 1000   ->  means 1024 weeks
// Note: This fix works for next 20 years since provided timestamp below
// See: https://stackoverflow.com/questions/56147606/
// See: https://www.cisa.gov/gps-week-number-roll-over
if ((gpsTime > 0) && (gpsTime < 1673000000000L))
  gpsTime += 619315200000L;

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/**
 *  Created by DanielHuang on 2024/8/2
 */
object GpsTimeTool {

    private const val LAST_RESET_TIME_2019_4_6_IN_MILLI = 1554508800000L
    private const val WEEKS_1024_IN_MILLISECONDS = 619315200000L

    /**
     *  部分裝置的 GPS 晶片有 Week Number Rollover 的問題
     *
     *  GPS系統的週數迴圈問題是由於它使用十位元參數來計算週數。
     *  這意味著從第零週開始計算，當達到第1,024週時會重置。
     *  第一次計算（或稱為「GPS紀元」）始於1980年1月6日，
     *  第一次重置發生在1999年8月21日。
     *  這意味著下一次重置將在 2019 的4月6日。
     *
     *  解法:
     *  // Adding 1024 weeks to fix Week Number Rollover issue for old GPS chips
     *  // 619315200000L = 1024 * 7 * 24 * 60 * 60 * 1000   ->  means 1024 weeks
     *  // Note: This fix works for next 20 years since provided timestamp below
     *  See: https://stackoverflow.com/questions/56147606/
     *  See: https://www.theverge.com/2019/3/8/18255847/gps-week-rollover-issue-2019-garmin-tomtom-devices-affected
     *
     *  @param time
     *  @return
     */
    fun fixTimeForRolloverIssue(time: Long): Long {
        return if ((time > 0) && (time < LAST_RESET_TIME_2019_4_6_IN_MILLI)) {
            time + WEEKS_1024_IN_MILLISECONDS
        } else {
            time
        }
    }
}