session-android/src/org/thoughtcrime/securesms/loki/Utilities.kt

package org.thoughtcrime.securesms.loki

import android.content.Context
import android.os.Handler
import android.os.Looper
import nl.komponents.kovenant.Promise
import nl.komponents.kovenant.deferred
import org.thoughtcrime.securesms.ApplicationContext
import org.thoughtcrime.securesms.database.DatabaseFactory
import org.thoughtcrime.securesms.logging.Log
import org.whispersystems.libsignal.util.guava.Optional
import org.whispersystems.signalservice.api.crypto.UnidentifiedAccessPair
import org.whispersystems.signalservice.api.messages.SignalServiceDataMessage
import org.whispersystems.signalservice.api.push.SignalServiceAddress
import org.whispersystems.signalservice.loki.api.LokiPairingAuthorisation

fun sendAuthorisationMessage(context: Context, contactHexEncodedPublicKey: String, authorisation: LokiPairingAuthorisation): Promise<Unit, Exception> {
  val messageSender = ApplicationContext.getInstance(context).communicationModule.provideSignalMessageSender()
  val address = SignalServiceAddress(contactHexEncodedPublicKey)
  val message = SignalServiceDataMessage.newBuilder().withBody("").withPairingAuthorisation(authorisation)

  // A REQUEST should always act as a friend request. A GRANT should always be replying back as a normal message.
  if (authorisation.type == LokiPairingAuthorisation.Type.REQUEST) {
    val preKeyBundle = DatabaseFactory.getLokiPreKeyBundleDatabase(context).generatePreKeyBundle(address.number)
    message.asFriendRequest(true).withPreKeyBundle(preKeyBundle)
  }

  return try {
    Log.d("Loki", "Sending authorisation message to $contactHexEncodedPublicKey")
    val result = messageSender.sendMessage(0, address, Optional.absent<UnidentifiedAccessPair>(), message.build())
    if (result.success == null) {
      val exception = when {
        result.isNetworkFailure -> "Failed to send authorisation message because of a Network Error"
        else -> "Failed to send authorisation message"
      }

      throw Exception(exception)
    }
    Promise.ofSuccess(Unit)
  } catch (e: Exception) {
    Log.d("Loki", "Failed to send authorisation message to: $contactHexEncodedPublicKey.")
    Promise.ofFail(e)
  }
}