package ecologylab.bigsemantics.httpclient;

import org.apache.http.client.params.ClientPNames;
import org.apache.http.client.protocol.RequestAcceptEncoding;
import org.apache.http.client.protocol.ResponseContentEncoding;
import org.apache.http.impl.client.AbstractHttpClient;
import org.apache.http.impl.conn.PoolingClientConnectionManager;
import org.apache.http.params.CoreProtocolPNames;

/**
 * A factory for HttpClient objects.
 * 
 * @author quyin
 */
public class HttpClientFactory
{

  private PoolingClientConnectionManager connectionManager;

  public HttpClientFactory()
  {
    this(20, 200);
  }

  public HttpClientFactory(int maxPerRoute, int maxTotal)
  {
    connectionManager = new PoolingClientConnectionManager();
    connectionManager.setDefaultMaxPerRoute(maxPerRoute);
    connectionManager.setMaxTotal(maxTotal);
  }

  public AbstractHttpClient create()
  {
    return create("");
  }

  public synchronized AbstractHttpClient create(String userAgent)
  {
    if (userAgent == null)
    {
      userAgent = "";
    }
    // From Apache HttpClient doc: "HttpClient is fully thread-safe when used
    // with a thread-safe connection manager." The
    // PoolingClientConnectionManager we are using is such as thread-safe one.
    AbstractHttpClient client = new RedirectHttpClient(connectionManager);
    prepareHttpClient(client);
    if (userAgent.length() > 0)
    {
      client.getParams().setParameter(CoreProtocolPNames.USER_AGENT, userAgent);
    }
    return client;
  }

  private void prepareHttpClient(AbstractHttpClient client)
  {
    client.getParams().setParameter(ClientPNames.HANDLE_REDIRECTS, true);
    client.addRequestInterceptor(new RequestAcceptEncoding());
    client.addResponseInterceptor(new ResponseContentEncoding());
    client.setRedirectStrategy(new BasicRedirectStrategy());
  }

}