বাংলাদেশে ৩৯৯ টাকায় আনলিমিটেড ইন্টারনেট eSIM App ও বিজনেস আর্কিটেকচার

// 1. Get EuiccManager instance
val euiccManager = context.getSystemService(Context.EUICC_SERVICE) as EuiccManager

if (!euiccManager.isEnabled) {
    Toast.makeText(context, "Device does not support eSIM", Toast.LENGTH_LONG).show()
    return
}

// 2. Prepare Activation Code received from Thoughts Backend API
// Format: LPA:1$smdp.provider.com$MATCHING_CODE
val activationCode = "LPA:1$smdp.thoughts-telecom.com$" + order.matchingId
val subscription = DownloadableSubscription.forActivationCode(activationCode)

// 3. Register PendingIntent callback for asynchronous download
val intent = Intent(context, EsimDownloadReceiver::class.java).apply {
    action = "com.thoughtsit.esim.DOWNLOAD_COMPLETE"
    putExtra("ORDER_ID", order.id)
}
val callbackIntent = PendingIntent.getBroadcast(
    context,
    0,
    intent,
    PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_MUTABLE
)

// 4. Trigger seamless download and switch profile automatically
euiccManager.downloadSubscription(subscription, true /* switchImmediately */, callbackIntent)

// Connect to SIM slot using Open Mobile API (OMAPI) on ANY Android phone
val seService = SEService(context, object : SEService.OnConnectedListener {
    override fun onConnected() {
        // 1. Locate the physical SIM slot with Thoughts Smart eUICC Card
        val readers = seService.readers
        val simReader = readers.firstOrNull { it.name.startsWith("SIM") }
        
        val session = simReader?.openSession()
        // 2. Open logical channel to GSMA ISD-R applet (AID: A0000005591010FFFFFFFF8900000100)
        val isdAid = byteArrayOf(0xA0.toByte(), 0x00, 0x00, 0x05, 0x59, 0x10, 0x10, 
                                 0xFF.toByte(), 0xFF.toByte(), 0xFF.toByte(), 0xFF.toByte(), 0x89.toByte(), 0x00, 0x00, 0x01, 0x00)
        val channel = session?.openLogicalChannel(isdAid)
        
        // 3. Send APDU command to download & authenticate eSIM profile from SM-DP+
        val installApdu = buildGsmaInstallApdu(matchingId, smdpAddress)
        val responseApdu = channel?.transmit(installApdu)
        
        // 4. eSIM profile is successfully written to the smart nano SIM card!
    }
})