/*
    * Copyright 2018 SPF4J.
    *
    * Licensed 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.spf4j.test.log;
  
  import com.google.common.annotations.VisibleForTesting;
  import com.google.common.collect.Interner;
  import com.google.common.collect.Interners;
  import java.util.List;
  import java.util.Objects;
  import javax.annotation.Nullable;
  import javax.annotation.ParametersAreNonnullByDefault;
  
  /**
   * @author Zoltan Farkas
   */
  @ParametersAreNonnullByDefault
  final class CompositeLogHandler implements LogConsumer {
  
    private static final Interner<CompositeLogHandler> INTERNER =
            Interners.newBuilder().concurrencyLevel(8).weak().build();
  
    private int hash = 0;
  
    @VisibleForTesting
    final List<LogHandler> logHandlers;
  
    private CompositeLogHandler(final List<LogHandler> logHandlers) {
      this.logHandlers = logHandlers;
    }
  
    @Nullable
    static LogConsumer from(final List<LogHandler> logHandlers) {
      if (logHandlers.isEmpty()) {
        return null;
      } else {
        return INTERNER.intern(new CompositeLogHandler(logHandlers));
      }
    }
  
    @Override
    public void accept(final TestLogRecord record) {
      TestLogRecord logRecord = record;
      for (LogHandler handler : logHandlers) {
        logRecord = handler.handle(logRecord);
        if (logRecord == null) {
          break;
        }
      }
    }
  
    @Override
    public int hashCode() {
      if (hash == 0) {
        hash = Objects.hashCode(this.logHandlers);
        return hash;
      } else {
        return hash;
      }
    }
  
    @Override
    public boolean equals(final Object obj) {
      if (this == obj) {
        return true;
      }
      if (obj == null) {
        return false;
      }
      if (getClass() != obj.getClass()) {
        return false;
      }
      final CompositeLogHandler other = (CompositeLogHandler) obj;
      return Objects.equals(this.logHandlers, other.logHandlers);
    }
  
    @Override
    public String toString() {
      return "CompositeLogHandler{" + "logHandlers=" + logHandlers + '}';
    }
  
  }