/*
    * Copyright 2012-2017 CodeLibs Project and the Others.
    *
    * 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.codelibs.fess.helper;
  
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.InputStream;
  
  import javax.annotation.PostConstruct;
  
  import org.codelibs.core.lang.StringUtil;
  import org.codelibs.fess.Constants;
  import org.codelibs.fess.util.ComponentUtil;
  import org.lastaflute.web.response.StreamResponse;
  import org.lastaflute.web.util.LaServletContextUtil;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  /**
   * Helper class for Open Search Description Document.
   *
   * @author shinsuke
   *
   */
  public class OpenSearchHelper {
      private static final Logger logger = LoggerFactory.getLogger(OpenSearchHelper.class);
  
      public String osddPath;
  
      public String encoding = Constants.UTF_8;
  
      public String contentType = "text/xml"; // "application/opensearchdescription+xml";
  
      private File osddFile;
  
      @PostConstruct
      public void init() {
          if (StringUtil.isNotBlank(osddPath)) {
              final String path = LaServletContextUtil.getServletContext().getRealPath(osddPath);
              osddFile = new File(path);
              if (!osddFile.isFile()) {
                  osddFile = null;
                  logger.warn(path + " was not found.");
              }
          } else {
              logger.info("OSDD file is not found.");
          }
      }
  
      public boolean hasOpenSearchFile() {
          return osddFile != null;
      }
  
      public StreamResponse asStream() {
          if (osddFile == null) {
              throw ComponentUtil.getResponseManager().new404("Unsupported OpenSearch response.");
          }
  
          return new StreamResponse(osddFile.getName()).contentType(contentType + "; charset=" + encoding).stream(out -> {
              try (InputStream ins = new FileInputStream(osddFile)) {
                  out.write(ins);
              }
          });
      }
  }