/*
    * Licensed to The Apereo Foundation under one or more contributor license
    * agreements. See the NOTICE file distributed with this work for additional
    * information regarding copyright ownership.
    *
    *
    * The Apereo Foundation licenses this file to you under the Educational
    * Community 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://opensource.org/licenses/ecl2.txt
   *
   * 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.opencastproject.editor.remote;
  
  import org.opencastproject.editor.api.EditingData;
  import org.opencastproject.editor.api.EditorService;
  import org.opencastproject.editor.api.EditorServiceException;
  import org.opencastproject.editor.api.ErrorStatus;
  import org.opencastproject.editor.api.LockData;
  import org.opencastproject.security.api.TrustedHttpClient;
  import org.opencastproject.serviceregistry.api.RemoteBase;
  import org.opencastproject.serviceregistry.api.ServiceRegistry;
  
  import org.apache.http.HttpEntity;
  import org.apache.http.HttpResponse;
  import org.apache.http.HttpStatus;
  import org.apache.http.client.entity.UrlEncodedFormEntity;
  import org.apache.http.client.methods.HttpDelete;
  import org.apache.http.client.methods.HttpGet;
  import org.apache.http.client.methods.HttpPost;
  import org.apache.http.entity.StringEntity;
  import org.apache.http.message.BasicNameValuePair;
  import org.apache.http.util.EntityUtils;
  import org.osgi.service.component.annotations.Component;
  import org.osgi.service.component.annotations.Reference;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.nio.charset.StandardCharsets;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.List;
  import java.util.Map;
  
  @Component(
      property = {
          "service.description=Editor Service Remote Proxy"
      },
      immediate = true,
      service = EditorService.class
  )
  public class EditorServiceRemoteImpl extends RemoteBase implements EditorService {
    private static final Logger logger = LoggerFactory.getLogger(EditorServiceRemoteImpl.class);
    public static final String EDIT_SUFFIX = "/edit.json";
    public static final String LOCK_SUFFIX = "/lock";
    public static final String METADATA_SUFFIX = "/metadata.json";
  
    /**
     * Creates a remote implementation for the given type of service.
     */
    public EditorServiceRemoteImpl() {
      super(EditorService.JOB_TYPE);
    }
  
    @Override
    public EditingData getEditData(String mediaPackageId)
            throws EditorServiceException {
      return EditingData.parse(doGetForMediaPackage(mediaPackageId, EDIT_SUFFIX));
    }
  
    @Override
    public void setEditData(String mediaPackageId, EditingData editingData) throws EditorServiceException {
      doPostForMediaPackage(mediaPackageId, EDIT_SUFFIX, editingData.toString());
    }
  
    @Override
    public String getMetadata(String mediaPackageId) throws EditorServiceException {
      return doGetForMediaPackage(mediaPackageId, METADATA_SUFFIX);
    }
  
    @Override
    public void lockMediaPackage(String mediaPackageId, LockData lockData) throws EditorServiceException {
      Map<String, String> params = new HashMap<>();
      params.put("uuid", lockData.getUUID());
      params.put("user", lockData.getUser());
      doPostFormForMediaPackage(mediaPackageId, LOCK_SUFFIX, params);
    }
  
    @Override
   public void unlockMediaPackage(String mediaPackageId, LockData lockData) throws EditorServiceException {
     doDeleteForMediaPackage(mediaPackageId, LOCK_SUFFIX + "/" + lockData.getUUID());
   }
 
   protected String doDeleteForMediaPackage(String mediaPackageId, final String urlSuffix)
           throws EditorServiceException {
     logger.debug("Editor Remote Lock POST Request for mediaPackage : '{}'", mediaPackageId);
     HttpDelete delete = new HttpDelete(mediaPackageId + urlSuffix);
     HttpResponse response = null;
     try {
       response = getResponse(delete, HttpStatus.SC_OK, HttpStatus.SC_NOT_FOUND, HttpStatus.SC_CONFLICT);
       if (response == null || response.getStatusLine() == null) {
         throw new EditorServiceException("Editor Remote call failed to respond", ErrorStatus.UNKNOWN);
       }
       if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
         evaluateResponseCode(response);
       }
       return null;
     } catch (Exception e) {
       throw new EditorServiceException("Editor Remote call failed", ErrorStatus.UNKNOWN, e);
     } finally {
       closeConnection(response);
     }
   }
 
   protected String doGetForMediaPackage(final String mediaPackageId, final String urlSuffix)
           throws EditorServiceException {
     logger.debug("Editor Remote GET Request for mediaPackage: '{}' to url: '{}'", mediaPackageId, urlSuffix);
     HttpGet get = new HttpGet(mediaPackageId + urlSuffix);
     HttpResponse response = null;
     try {
       response = getResponse(get, HttpStatus.SC_OK, HttpStatus.SC_NOT_FOUND, HttpStatus.SC_CONFLICT,
         HttpStatus.SC_BAD_REQUEST);
       if (response == null || response.getStatusLine() == null) {
         throw new EditorServiceException("HTTP Request failed", ErrorStatus.UNKNOWN);
       }
       if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
         evaluateResponseCode(response);
         return null;
       } else {
         HttpEntity httpEntity = response.getEntity();
         if (httpEntity != null) {
           return EntityUtils.toString(httpEntity);
         } else {
           throw new EditorServiceException("Editor Remote call failed", ErrorStatus.UNKNOWN);
         }
       }
     } catch (IOException e) {
       throw new EditorServiceException("Editor Remote call failed", ErrorStatus.UNKNOWN, e);
     } finally {
       closeConnection(response);
     }
   }
 
   protected void doPostForMediaPackage(final String mediaPackageId, final String urlSuffix, final String data)
           throws EditorServiceException {
     logger.debug("Editor Remote POST Request for mediaPackage : '{}' to url: '{}'", mediaPackageId, urlSuffix);
     HttpPost post = new HttpPost(mediaPackageId + urlSuffix);
     HttpResponse response = null;
     try {
       StringEntity editJson = new StringEntity(data, StandardCharsets.UTF_8);
       post.setEntity(editJson);
       post.setHeader("Content-type", "application/json");
       response = getResponse(post, HttpStatus.SC_OK, HttpStatus.SC_NOT_FOUND, HttpStatus.SC_BAD_REQUEST,
               HttpStatus.SC_CONFLICT);
       if (response == null || response.getStatusLine() == null) {
         throw new EditorServiceException("No response for setEditData", ErrorStatus.UNKNOWN);
       }
       if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
         evaluateResponseCode(response);
       }
     } finally {
       closeConnection(response);
     }
   }
 
   protected void doPostFormForMediaPackage(final String mediaPackageId, final String urlSuffix,
           final Map<String, String> params)
           throws EditorServiceException {
     logger.debug("Editor Remote POST Request for mediaPackage : '{}' to url: '{}'", mediaPackageId, urlSuffix);
     HttpPost post = new HttpPost(mediaPackageId + urlSuffix);
     HttpResponse response = null;
     try {
       List<BasicNameValuePair> formParams = new ArrayList<>();
       for (String field : params.keySet()) {
         formParams.add(new BasicNameValuePair(field, params.get(field)));
       }
       post.setEntity(new UrlEncodedFormEntity(formParams, "UTF-8"));
       response = getResponse(post, HttpStatus.SC_OK, HttpStatus.SC_NOT_FOUND, HttpStatus.SC_BAD_REQUEST,
               HttpStatus.SC_CONFLICT);
       if (response == null || response.getStatusLine() == null) {
         throw new EditorServiceException("No response for setEditData", ErrorStatus.UNKNOWN);
       }
       if (response.getStatusLine().getStatusCode() != HttpStatus.SC_OK) {
         evaluateResponseCode(response);
       }
     } catch (UnsupportedEncodingException e) {
       throw new EditorServiceException(e.getMessage(), ErrorStatus.UNKNOWN);
     } finally {
       closeConnection(response);
     }
   }
 
   protected void evaluateResponseCode(HttpResponse response) throws EditorServiceException {
     switch (response.getStatusLine().getStatusCode()) {
       case HttpStatus.SC_NOT_FOUND:
         throw new EditorServiceException("MediaPackage not found", ErrorStatus.MEDIAPACKAGE_NOT_FOUND);
       case HttpStatus.SC_CONFLICT:
         throw new EditorServiceException(response.getEntity().toString(), ErrorStatus.MEDIAPACKAGE_LOCKED);
       case HttpStatus.SC_BAD_REQUEST:
         throw new EditorServiceException("Request invalid", ErrorStatus.UNKNOWN);
       default:
         throw new EditorServiceException("Editor Remote call failed", ErrorStatus.UNKNOWN);
     }
   }
 
   @Reference
   public void setTrustedHttpClient(TrustedHttpClient client) {
     this.client = client;
   }
 
   @Reference
   public void setRemoteServiceManager(ServiceRegistry remoteServiceManager) {
     this.remoteServiceManager = remoteServiceManager;
   }
 }