/*
    * Copyright (c) 2016 ingenieux Labs
    *
    * 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 br.com.ingenieux.mojo.beanstalk.config;
  
  import com.amazonaws.services.elasticbeanstalk.model.ApplicationDescription;
  import com.amazonaws.services.elasticbeanstalk.model.ConfigurationOptionSetting;
  import com.amazonaws.services.elasticbeanstalk.model.ConfigurationSettingsDescription;
  import com.amazonaws.services.elasticbeanstalk.model.DescribeApplicationsRequest;
  import com.amazonaws.services.elasticbeanstalk.model.DescribeApplicationsResult;
  import com.amazonaws.services.elasticbeanstalk.model.DescribeConfigurationSettingsRequest;
  import com.amazonaws.services.elasticbeanstalk.model.DescribeConfigurationSettingsResult;
  
  import org.apache.commons.io.IOUtils;
  import org.apache.commons.lang.StringUtils;
  import org.apache.maven.plugin.MojoFailureException;
  import org.apache.maven.plugins.annotations.Mojo;
  import org.apache.maven.plugins.annotations.Parameter;
  
  import java.io.File;
  import java.io.FileWriter;
  import java.io.IOException;
  import java.io.StringReader;
  import java.util.ArrayList;
  import java.util.List;
  
  import br.com.ingenieux.mojo.beanstalk.AbstractBeanstalkMojo;
  
  /**
   * Describes Available Configuration Templates
   *
   * @author Aldrin Leal
   * @since 0.2.5
   */
  @Mojo(name = "describe-configuration-templates")
  public class DescribeConfigurationTemplatesMojo extends AbstractBeanstalkMojo {
  
    private static final String ENDL = System.getProperty("line.separator");
  
    /**
     * Beanstalk Application Name
     */
    @Parameter(property = "beanstalk.applicationName", defaultValue = "${project.artifactId}", required = true)
    protected String applicationName;
  
    /**
     * Configuration Template Name (Optional)
     */
    @Parameter(property = "beanstalk.configurationTemplate")
    String configurationTemplate;
  
    /**
     * Output file (Optional)
     */
    @Parameter(property = "beanstalk.outputFile")
    File outputFile;
  
    @Override
    protected Object executeInternal() throws Exception {
      DescribeApplicationsRequest req = new DescribeApplicationsRequest().withApplicationNames(applicationName);
      boolean bConfigurationTemplateDefined = StringUtils.isNotBlank(configurationTemplate);
  
      DescribeApplicationsResult apps = getService().describeApplications(req);
  
      List<ApplicationDescription> applications = apps.getApplications();
  
      if (applications.isEmpty()) {
        String errorMessage = "Application ('" + applicationName + "') not found!";
  
        getLog().warn(errorMessage);
  
        throw new MojoFailureException(errorMessage);
      }
  
      ApplicationDescription desc = applications.get(0);
  
      List<String> configTemplates = desc.getConfigurationTemplates();
  
      if (bConfigurationTemplateDefined) {
        describeConfigurationTemplate(configurationTemplate);
      } else {
        for (String availConfigTemplate : configTemplates) {
          describeConfigurationTemplate(availConfigTemplate);
        }
      }
  
     return null;
   }
 
   void describeConfigurationTemplate(String configTemplateName) throws Exception {
     DescribeConfigurationSettingsRequest req =
         new DescribeConfigurationSettingsRequest().withApplicationName(applicationName).withTemplateName(configTemplateName);
 
     DescribeConfigurationSettingsResult configSettings = getService().describeConfigurationSettings(req);
 
     List<String> buf = new ArrayList<String>();
 
     buf.add("<optionSettings>");
 
     for (ConfigurationSettingsDescription configSetting : configSettings.getConfigurationSettings()) {
       for (ConfigurationOptionSetting setting : configSetting.getOptionSettings()) {
         if (harmfulOptionSettingP(null, setting)) {
           continue;
         }
         buf.add("  <optionSetting>");
         buf.add(String.format("    <%s>%s</%1$s>", "namespace", setting.getNamespace()));
         buf.add(String.format("    <%s>%s</%1$s>", "optionName", setting.getOptionName()));
         buf.add(String.format("    <%s>%s</%1$s>", "value", setting.getValue()));
         buf.add("  </optionSetting>");
       }
     }
 
     buf.add("</optionSettings>");
 
     if (null != outputFile) {
       getLog().info("Dumping results to file: " + outputFile.getName());
 
       String bufChars = StringUtils.join(buf.iterator(), ENDL);
       FileWriter writer = null;
 
       try {
         writer = new FileWriter(outputFile);
 
         IOUtils.copy(new StringReader(bufChars), writer);
       } catch (IOException e) {
         throw new RuntimeException("Failure when writing to file: " + outputFile.getName(), e);
       } finally {
         IOUtils.closeQuietly(writer);
       }
     } else {
       getLog().info("Dumping results to stdout");
 
       for (String e : buf) {
         getLog().info(e);
       }
     }
   }
 }