package org.xmlsh.aws;

import java.io.IOException;
import java.util.Collection;
import java.util.List;
import javax.xml.stream.XMLStreamException;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.xmlsh.aws.util.AWSEC2Command;
import org.xmlsh.core.CoreException;
import org.xmlsh.core.Options;
import org.xmlsh.core.SafeXMLStreamWriter;
import org.xmlsh.core.UnexpectedException;
import org.xmlsh.core.XValue;
import org.xmlsh.core.io.OutputPort;
import org.xmlsh.util.Util;
import com.amazonaws.AmazonServiceException;
import com.amazonaws.services.ec2.model.DescribeInstancesRequest;
import com.amazonaws.services.ec2.model.Filter;
import com.amazonaws.services.ec2.model.Reservation;
import net.sf.saxon.s9api.SaxonApiException;

public class ec2DescribeInstances extends AWSEC2Command {

  private static Logger mLogger = LogManager.getLogger();

  /**
   * @param args
   * @throws IOException
   */
  @Override
  public int run(List<XValue> args) throws Exception {

    Options opts = getOptions();
    parseOptions(opts, args);

    args = opts.getRemainingArgs();
    parseCommonOptions(opts);

    setSerializeOpts(this.getSerializeOpts(opts));

    try {
      getEC2Client(opts);
    } catch (UnexpectedException e) {
      usage(e.getLocalizedMessage());
      return 1;

    }

    Collection<Filter> filters = opts.hasOpt("filter")
        ? parseFilters(Util.toStringList(opts.getOptValues("filter"))) : null;

    int ret = describe(args, filters);

    return ret;

  }

  private int describe(List<XValue> args, Collection<Filter> filters)
      throws IOException, XMLStreamException, SaxonApiException, CoreException,
      InterruptedException {

    OutputPort stdout = this.getStdout();
    mWriter = new SafeXMLStreamWriter(
        stdout.asXMLStreamWriter(getSerializeOpts()));

    startDocument();
    startElement(this.getName());

    DescribeInstancesRequest request = new DescribeInstancesRequest();
    if(args != null && args.size() > 0) {

      request.setInstanceIds(Util.toStringList(args));

    }
    if(filters != null)
      request.setFilters(filters);

    traceCall("describeInstances");

    List<Reservation> result = null;

    int retry = rateRetry;
    int delay = retryDelay;
    do {
      try {
        result = getAWSClient().describeInstances(request).getReservations();
        break;
      } catch (AmazonServiceException e) {
        mShell.printErr("AmazonServiceException", e);
        if(retry > 0
            && Util.isEqual("RequestLimitExceeded", e.getErrorCode())) {
          mShell.printErr("AWS RequestLimitExceeded - sleeping " + delay);
          Thread.sleep(delay);
          retry--;
          delay *= 2;

        }
        else
          throw e;

      }
    } while(retry > 0);

    for(Reservation res : result) {
      writeReservation(res);

    }

    endElement();
    endDocument();
    closeWriter();

    stdout.writeSequenceTerminator(getSerializeOpts());

    return 0;

  }

  @Override
  public void usage() {
    super.usage("Usage: ec2-describe-instances [options] [instance-id]");
  }

}