/*
    * ====================================================================
    * 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.
   * ====================================================================
   *
   * This software consists of voluntary contributions made by many
   * individuals on behalf of the Apache Software Foundation.  For more
   * information on the Apache Software Foundation, please see
   * <http://www.apache.org/>.
   *
   */
  package org.apache.hc.core5.http.nio.support;
  
  import org.apache.hc.core5.function.Decorator;
  import org.apache.hc.core5.function.Supplier;
  import org.apache.hc.core5.http.HttpException;
  import org.apache.hc.core5.http.HttpRequest;
  import org.apache.hc.core5.http.HttpRequestMapper;
  import org.apache.hc.core5.http.HttpStatus;
  import org.apache.hc.core5.http.MisdirectedRequestException;
  import org.apache.hc.core5.http.nio.AsyncServerExchangeHandler;
  import org.apache.hc.core5.http.nio.HandlerFactory;
  import org.apache.hc.core5.http.protocol.HttpContext;
  import org.apache.hc.core5.util.Args;
  
  /**
   * Factory for {@link AsyncServerExchangeHandler} instances that make use
   * of {@link HttpRequestMapper} to dispatch
   * the request to a particular {@link AsyncServerExchangeHandler} for processing.
   *
   * @since 5.0
   */
  public final class DefaultAsyncResponseExchangeHandlerFactory implements HandlerFactory<AsyncServerExchangeHandler> {
  
      private final HttpRequestMapper<Supplier<AsyncServerExchangeHandler>> mapper;
      private final Decorator<AsyncServerExchangeHandler> decorator;
  
      public DefaultAsyncResponseExchangeHandlerFactory(
              final HttpRequestMapper<Supplier<AsyncServerExchangeHandler>> mapper,
              final Decorator<AsyncServerExchangeHandler> decorator) {
          this.mapper = Args.notNull(mapper, "Request handler mapper");
          this.decorator = decorator;
      }
  
      public DefaultAsyncResponseExchangeHandlerFactory(final HttpRequestMapper<Supplier<AsyncServerExchangeHandler>> mapper) {
          this(mapper, null);
      }
  
      private AsyncServerExchangeHandler createHandler(final HttpRequest request,
                      final HttpContext context) throws HttpException {
          try {
              final Supplier<AsyncServerExchangeHandler> supplier = mapper.resolve(request, context);
              return supplier != null
                              ? supplier.get()
                              : new ImmediateResponseExchangeHandler(HttpStatus.SC_NOT_FOUND, "Resource not found");
          } catch (final MisdirectedRequestException ex) {
              return new ImmediateResponseExchangeHandler(HttpStatus.SC_MISDIRECTED_REQUEST,
                              "Not authoritative");
          }
      }
  
      @Override
      public AsyncServerExchangeHandler create(final HttpRequest request, final HttpContext context) throws HttpException {
          final AsyncServerExchangeHandler handler = createHandler(request, context);
          if (handler != null) {
              return decorator != null ? decorator.decorate(handler) : handler;
          }
          return null;
      }
  
  }