/*
 * Copyright © 2014-2021 The Android Password Store Authors. All Rights Reserved.
 * SPDX-License-Identifier: Apache-2.0
 */
@file:JvmName("OpenPgpDecryptionResult")

package org.openintents.openpgp

import android.os.Parcel
import android.os.Parcelable
import android.os.Parcelable.Creator

public class OpenPgpDecryptionResult() : Parcelable {

  private var result = 0
  private var sessionKey: ByteArray? = null
  private var decryptedSessionKey: ByteArray? = null

  private constructor(result: Int) : this() {
    this.result = result
    sessionKey = null
    decryptedSessionKey = null
  }

  private constructor(
    result: Int,
    sessionKey: ByteArray?,
    decryptedSessionKey: ByteArray?
  ) : this() {
    this.result = result
    if (sessionKey == null != (decryptedSessionKey == null)) {
      throw AssertionError("sessionkey must be null iff decryptedSessionKey is null")
    }
    this.sessionKey = sessionKey
    this.decryptedSessionKey = decryptedSessionKey
  }

  public fun getResult(): Int {
    return result
  }

  public fun hasDecryptedSessionKey(): Boolean {
    return sessionKey != null
  }

  public fun getSessionKey(): ByteArray? {
    return if (sessionKey == null) {
      null
    } else sessionKey!!.copyOf(sessionKey!!.size)
  }

  public fun getDecryptedSessionKey(): ByteArray? {
    return if (sessionKey == null || decryptedSessionKey == null) {
      null
    } else decryptedSessionKey!!.copyOf(decryptedSessionKey!!.size)
  }

  override fun describeContents(): Int {
    return 0
  }

  override fun writeToParcel(dest: Parcel, flags: Int) {
    /**
     * NOTE: When adding fields in the process of updating this API, make sure to bump
     * [.PARCELABLE_VERSION].
     */
    dest.writeInt(PARCELABLE_VERSION)
    // Inject a placeholder that will store the parcel size from this point on
    // (not including the size itself).
    val sizePosition = dest.dataPosition()
    dest.writeInt(0)
    val startPosition = dest.dataPosition()
    // version 1
    dest.writeInt(result)
    // version 2
    dest.writeByteArray(sessionKey)
    dest.writeByteArray(decryptedSessionKey)
    // Go back and write the size
    val parcelableSize = dest.dataPosition() - startPosition
    dest.setDataPosition(sizePosition)
    dest.writeInt(parcelableSize)
    dest.setDataPosition(startPosition + parcelableSize)
  }

  override fun toString(): String {
    return "\nresult: $result"
  }

  public companion object CREATOR : Creator<OpenPgpDecryptionResult> {

    /**
     * Since there might be a case where new versions of the client using the library getting old
     * versions of the protocol (and thus old versions of this class), we need a versioning system
     * for the parcels sent between the clients and the providers.
     */
    private const val PARCELABLE_VERSION = 2

    // content not encrypted
    public const val RESULT_NOT_ENCRYPTED: Int = -1

    // insecure!
    public const val RESULT_INSECURE: Int = 0

    // encrypted
    public const val RESULT_ENCRYPTED: Int = 1

    override fun createFromParcel(source: Parcel): OpenPgpDecryptionResult? {
      val version = source.readInt() // parcelableVersion
      val parcelableSize = source.readInt()
      val startPosition = source.dataPosition()
      val result = source.readInt()
      val sessionKey = if (version > 1) source.createByteArray() else null
      val decryptedSessionKey = if (version > 1) source.createByteArray() else null
      val vr = OpenPgpDecryptionResult(result, sessionKey, decryptedSessionKey)
      // skip over all fields added in future versions of this parcel
      source.setDataPosition(startPosition + parcelableSize)
      return vr
    }

    override fun newArray(size: Int): Array<OpenPgpDecryptionResult?> {
      return arrayOfNulls(size)
    }
  }
}