package jalview.ws;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;

/**
 * Helpful procedures for working with services via HTTPClient
 * @author jimp
 *
 */
public class HttpClientUtils
{
  /**
   * do a minimal HTTP post with URL-Encoded parameters passed in the Query
   * string
   * 
   * @param postUrl
   * @param vals
   * @return Reader containing content, if any, or null if no entity returned.
   * @throws IOException
   * @throws ClientProtocolException
   * @throws Exception
   */
  public static BufferedReader doHttpUrlPost(String postUrl,
          List<NameValuePair> vals) throws ClientProtocolException,
          IOException
  {
    HttpClient httpclient = new DefaultHttpClient();
    HttpPost httppost = new HttpPost(postUrl);
    UrlEncodedFormEntity ue = new UrlEncodedFormEntity(vals, "UTF-8");
    httppost.setEntity(ue);
    HttpResponse response = httpclient.execute(httppost);
    HttpEntity resEntity = response.getEntity();

    if (resEntity != null)
    {
      BufferedReader r = new BufferedReader(new InputStreamReader(
              resEntity.getContent()));
      return r;
    }
    else
    {
      return null;
    }
  }

}