/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF 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
 *
 *     http://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 org.apache.phoenix.transaction;

import java.io.IOException;
import org.apache.phoenix.coprocessorclient.MetaDataProtocol;

public class TransactionFactory {

  public enum Provider {
    // The provider formerly known as TEPHRA, deliberately renamed to warn downstreams
    // that Tephra support no longer exists, while preserving the ordinal for backwards
    // compatible use in system schema.
    NOTAVAILABLE((byte) 1, NotAvailableTransactionProvider.getInstance()),
    // The OMID provider.
    OMID((byte) 2, OmidTransactionProvider.getInstance());

    private final byte code;
    private final PhoenixTransactionProvider provider;

    Provider(byte code, PhoenixTransactionProvider provider) {
      this.code = code;
      this.provider = provider;
    }

    public static Provider[] available() {
      return new Provider[] { OMID };
    }

    public byte getCode() {
      return this.code;
    }

    public static Provider fromCode(int code) {
      if (code < 1 || code > Provider.values().length) {
        throw new IllegalArgumentException("Invalid TransactionFactory.Provider " + code);
      }
      return Provider.values()[code - 1];
    }

    public static Provider getDefault() {
      return OMID;
    }

    public PhoenixTransactionProvider getTransactionProvider() {
      return provider;
    }
  }

  public static PhoenixTransactionProvider getTransactionProvider(Provider provider) {
    return provider.getTransactionProvider();
  }

  public static PhoenixTransactionProvider getTransactionProvider(byte[] txState,
    int clientVersion) {
    if (txState == null || txState.length == 0) {
      return null;
    }
    Provider provider = (clientVersion < MetaDataProtocol.MIN_SYSTEM_TABLE_TIMESTAMP_4_14_0)
      ? Provider.NOTAVAILABLE
      : Provider.fromCode(txState[txState.length - 1]);
    return provider.getTransactionProvider();
  }

  public static PhoenixTransactionContext getTransactionContext(byte[] txState, int clientVersion)
    throws IOException {
    PhoenixTransactionProvider provider = getTransactionProvider(txState, clientVersion);
    if (provider == null) {
      return null;
    }
    return provider.getTransactionContext(txState);
  }
}
