/*
    * 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.myfaces.tobago.example.demo.bestpractice;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.myfaces.tobago.example.demo.DemoException;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import javax.enterprise.context.RequestScoped;
  import javax.faces.context.FacesContext;
  import javax.inject.Named;
  import javax.servlet.http.HttpServletResponse;
  import java.io.IOException;
  import java.io.InputStream;
  import java.lang.invoke.MethodHandles;
  
  @RequestScoped
  @Named
  public class BestPracticeController {
  
    private static final Logger LOG = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());
  
    private String status;
  
    public String throwException() {
      throw new DemoException("This exception is forced by the user.");
    }
  
    public String viewPdfInBrowser() {
      return viewFile(false, true);
    }
  
    public String viewPdfOutsideOfBrowser() {
      return viewFile(true, true);
    }
  
    public String viewFile(final boolean outside, final boolean pdf) {
  
      final FacesContext facesContext = FacesContext.getCurrentInstance();
  
      try (final InputStream inputStream = getInputStream(pdf, facesContext)) {
        final HttpServletResponse response = (HttpServletResponse) facesContext.getExternalContext().getResponse();
        response.setContentType(pdf ? "application/pdf" : "text/plain");
        if (outside) {
          response.setHeader("Content-Disposition", "attachment; filename=x-sample." + (pdf ? "pdf" : "txt"));
        }
        IOUtils.copy(inputStream, response.getOutputStream());
      } catch (final IOException e) {
        LOG.warn("Cannot deliver " + (pdf ? "pdf" : "txt"), e);
        return "error"; // response via faces
      }
      facesContext.responseComplete();
      return null;
    }
  
    private InputStream getInputStream(boolean pdf, FacesContext facesContext) {
      final String path = "content/30-concept/24-non-faces-response/x-sample." + (pdf ? "pdf" : "txt");
      InputStream inputStream = facesContext.getExternalContext().getResourceAsStream(path);
      if (inputStream == null) {
        inputStream = facesContext.getExternalContext().getResourceAsStream("/" + path);
      }
      return inputStream;
    }
  
    public String getStatus() {
      return status;
    }
  
    public void setStatus(final String status) {
      this.status = status;
    }
  }