/*
    * Copyright 2023 The Netty Project
    *
    * The Netty Project licenses this file to you under the Apache License,
    * version 2.0 (the "License"); you may not use this file except in compliance
    * with the License. You may obtain a copy of the License at:
    *
    *   https://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
   * License for the specific language governing permissions and limitations
   * under the License.
   */
  package io.netty.handler.codec.quic;
  
  import io.netty.util.internal.PlatformDependent;
  import org.jetbrains.annotations.Nullable;
  
  final class BoringSSLSessionTicketCallback {
  
      // As we dont assume to have a lot of keys configured we will just use an array for now as a data store.
      private volatile byte[][] sessionKeys;
  
      // Accessed via JNI.
      byte @Nullable [] findSessionTicket(byte @Nullable [] keyname) {
          byte[][] keys = this.sessionKeys;
          if (keys == null || keys.length == 0) {
              return null;
          }
          if (keyname == null) {
              return keys[0];
          }
  
          for (int i = 0; i < keys.length; i++) {
              byte[] key = keys[i];
              if (PlatformDependent.equals(keyname, 0, key, 1, keyname.length)) {
                  return key;
              }
          }
          return null;
      }
  
      void setSessionTicketKeys(SslSessionTicketKey @Nullable [] keys) {
          if (keys != null && keys.length != 0) {
              byte[][] sessionKeys = new byte[keys.length][];
              for (int i = 0; i < keys.length; ++i) {
                  SslSessionTicketKey key = keys[i];
                  byte[] binaryKey = new byte[49];
                  // We mark the first key as preferred by using 1 as byte marker
                  binaryKey[0] = i == 0 ? (byte) 1 : (byte) 0;
                  int dstCurPos = 1;
                  System.arraycopy(key.name, 0, binaryKey, dstCurPos, 16);
                  dstCurPos += 16;
                  System.arraycopy(key.hmacKey, 0, binaryKey, dstCurPos, 16);
                  dstCurPos += 16;
                  System.arraycopy(key.aesKey, 0, binaryKey, dstCurPos, 16);
                  sessionKeys[i] = binaryKey;
              }
              this.sessionKeys = sessionKeys;
          } else {
              sessionKeys = null;
          }
      }
  }