/**
    * Copyright 2007 Björn Voß
    *
    * 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 net.sf.oxclient.communication;
  
  import java.io.IOException;
  import java.io.UnsupportedEncodingException;
  import java.net.URLDecoder;
  import java.util.HashMap;
  import java.util.Map;
  
  import net.sf.oval.constraint.AssertFieldConstraints;
  import net.sf.oval.constraint.NotEmpty;
  import net.sf.oval.constraint.NotNull;
  import net.sf.oval.guard.Guarded;
  import net.sf.oxclient.IUser;
  
  import org.apache.commons.httpclient.Cookie;
  import org.apache.commons.httpclient.HttpClient;
  import org.apache.commons.httpclient.HttpException;
  import org.apache.commons.httpclient.HttpMethod;
  import org.apache.commons.httpclient.HttpState;
  import org.apache.commons.httpclient.URI;
  import org.apache.commons.httpclient.URIException;
  import org.apache.commons.httpclient.methods.GetMethod;
  
  @Guarded
  public class HttpCommunicationClient implements ICommunicationClient {
  
  	private final HttpClient httpClient;
  	private String oxSessionid = null;
  
  	@NotNull
  	@NotEmpty
  	private String base = "/ajax/";
  
  	@NotNull
  	@NotEmpty
  	private String urlDecoding = "UTF-8";
  
  	@NotNull
  	@NotEmpty
  	private String cookiePrefix = "open-xchange-session-";
  
  	public HttpCommunicationClient(@NotNull final HttpClient httpClient) {
  		this.httpClient = httpClient;
  	}
  
  	public void setBase(@AssertFieldConstraints final String base) {
  		this.base = base;
  	}
  
  	public void setUrlDecoding(@AssertFieldConstraints final String urlDecoding) {
  		this.urlDecoding = urlDecoding;
  	}
  
  	public void setCookiePrefix(@AssertFieldConstraints final String cookiePrefix) {
  		this.cookiePrefix = cookiePrefix;
  	}
  
  	public String getOxSessionid() {
  		return this.oxSessionid;
  	}
  
  
  	public void setOxSessionid(final String sessionid) {
  		this.oxSessionid = sessionid;
  	}
  
  
  	public HttpClient getHttpClient() {
  		return this.httpClient;
  	}
  
  
  	public String getBase() {
  		return this.base;
  	}
  
  
  	public String getUrlDecoding() {
  		return this.urlDecoding;
  	}
  
  
  	public String getCookiePrefix() {
  		return this.cookiePrefix;
 	}
 
 
 	public String generateURI(
 			final Map<String, String> params,
 			final String modul) {
 		final StringBuffer sb = new StringBuffer();
 		sb.append(this.base);
 		sb.append(modul);
 		sb.append("?");
 		for (final Map.Entry<String, String> entry : params.entrySet()) {
 			sb.append(entry.getKey());
 			sb.append("=");
 			try {
 				sb.append(URLDecoder.decode(entry.getValue(), this.urlDecoding));
 			} catch (final UnsupportedEncodingException e) {
 				throw new CommunicationException(e.getMessage(), e);
 			}
 			sb.append("&");
 		}
 		sb.append("session=");
 		sb.append(this.oxSessionid);
 		return sb.toString();
 	}
 
 	public String execute(final HttpMethod method) {
 		try {
 			this.httpClient.executeMethod(method);
 			final String response = method.getResponseBodyAsString();
 			System.out.println(response);
 			return response;
 		} catch (final HttpException e) {
 			throw new CommunicationException(e.getMessage(), e);
 		} catch (final IOException e) {
 			throw new CommunicationException(e.getMessage(), e);
 		} finally {
 			method.releaseConnection();
 		}
 	}
 
 
 
 	public String findSessionId() {
 		for (final Cookie cookie : this.httpClient.getState()
 				.getCookies()) {
 			final String name = cookie.getName();
 			if (name.startsWith(this.cookiePrefix)) {
 				return name.substring(this.cookiePrefix.length(), name.length());
 			}
 		}
 		return null;
 	}
 
 	public String login(final IUser user) {
 		final Map<String, String> params = new HashMap<String, String>(2);
 		params.put("action", "login");
 		params.put("name", user.getLogin());
 		params.put("password", user.getPassword());
 		final String uri = generateURI(
 				params,
 				"login");
 		execute(new GetMethod(uri));
 		this.oxSessionid = findSessionId();
 		return this.oxSessionid;
 	}
 
 	public String query(final Map<String, String> params, final String modul) {
 		final String uri = generateURI(
 				params,
 				modul);
 		System.out.println(uri);
 		final GetMethod getMethod = new GetMethod(uri);
 		return execute(getMethod);
 	}
 
 
 	/* (non-Javadoc)
 	 * @see net.sf.oxclient.communication.ICommunicationClient#getOXSessionCookie()
 	 */
 	public Cookie getSessionCookie() {
 		final HttpState state = this.httpClient.getState();
 		if (state != null ) {
 			for (final Cookie cookie : state.getCookies()) {
 				if (cookie.getName().startsWith(this.cookiePrefix)) {
 					return cookie;
 				}
 			}
 		}
 		return null;
 	}
 
 	/* (non-Javadoc)
 	 * @see net.sf.oxclient.communication.ICommunicationClient#getServer()
 	 */
 	public String getServerURL() {
 		return this.httpClient.getHostConfiguration().getHostURL();
 	}
 
 	/* (non-Javadoc)
 	 * @see net.sf.oxclient.communication.ICommunicationClient#setServer(java.lang.String)
 	 */
 	public void setServerURL(final String url) {
 		try {
 			this.httpClient.getHostConfiguration().setHost(new URI(url, false));
 		} catch (final URIException e) {
 			throw new IllegalArgumentException("can't parse '"+url+"' into uri", e);
 		}
 	}
 
 
 
 }