<!--

BigBlueButton - http://www.bigbluebutton.org

Copyright (c) 2008-2009 by respective authors (see below). All rights reserved.

BigBlueButton is free software; you can redistribute it and/or modify it under the 
terms of the GNU Lesser General Public License as published by the Free Software 
Foundation; either version 3 of the License, or (at your option) any later 
version. 

BigBlueButton is distributed in the hope that it will be useful, but WITHOUT ANY 
WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A 
PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along 
with BigBlueButton; if not, If not, see <http://www.gnu.org/licenses/>.

Author: Fred Dixon <ffdixon@bigbluebutton.org>

-->

<%@ page
    import="java.util.*,java.io.*,java.net.*,javax.crypto.*,javax.xml.parsers.*,org.w3c.dom.Document,org.xml.sax.*"
    errorPage="error.jsp" %>

<%@ page import="org.apache.commons.codec.digest.*"%>
<%@ include file="../demo/bbb_api_conf.jsp"%>

<%!
// 
// Create a meeting and return a URL to join it as moderator
//
public String getJoinURL(String username, String meetingID) {
        String base_url_create = BigBlueButtonURL + "api/create?";
        String base_url_join = BigBlueButtonURL + "api/join?";
        
        String welcome_param = "";
        String checksum = "";
        Integer voiceBridge = new Integer(99999);
                        
        String create_parameters = "name=" + urlEncode(meetingID) + "&meetingID=" + urlEncode(meetingID)
                                    + welcome_param + "&attendeePW=ap&moderatorPW=mp&voiceBridge="+voiceBridge;
            
        Document doc = null;

        try {
            // Attempt to create a meeting using meetingID
            String xml = getURL(base_url_create + create_parameters + "&checksum=" + checksum("create" + create_parameters + salt) );
            doc = parseXml(xml);        
        } catch (Exception e) {
            e.printStackTrace();
        }

        if (doc.getElementsByTagName("returncode").item(0).getTextContent()
                .trim().equals("SUCCESS")) {
            String join_parameters = "meetingID=" + urlEncode(meetingID) + "&fullName=" + urlEncode(username)
                + "&password=mp";
    
            return base_url_join + join_parameters + "&checksum=" + checksum("join" + join_parameters + salt);

        }
        return doc.getElementsByTagName("messageKey").item(0).getTextContent().trim() 
        + ": " + doc.getElementsByTagName("message").item(0).getTextContent().trim();
    }


//
// getJoinURLViewer() -- Get the URL to join a meeting as viewer
//
public String getJoinURLViewer(String username, String meetingID) {

    String base_url_join = BigBlueButtonURL + "api/join?";

    String join_parameters = "meetingID=" + urlEncode(meetingID) + "&fullName=" + urlEncode(username)
            + "&password=ap";
    
    return base_url_join + join_parameters + "&checksum=" + checksum("join" + join_parameters + salt);
}

    //
    // checksum() -- create a hash based on the shared salt (located in bbb_api_conf.jsp)
    //
    public static String checksum(String s) {
        String checksum = "";
        try {
            checksum = org.apache.commons.codec.digest.DigestUtils.shaHex(s);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return checksum;
    }

    //
    // getURL() -- fetch a URL and return its contents as a String
    //
    public static String getURL(String url) {
        StringBuffer response = null;

        try {
            URL u = new URL(url);
            HttpURLConnection httpConnection = (HttpURLConnection) u
                    .openConnection();

            httpConnection.setUseCaches(false);
            httpConnection.setDoOutput(true);
            httpConnection.setRequestMethod("GET");

            httpConnection.connect();
            int responseCode = httpConnection.getResponseCode();
            if (responseCode == HttpURLConnection.HTTP_OK) {
                InputStream input = httpConnection.getInputStream();

                // Read server's response.
                response = new StringBuffer();
                Reader reader = new InputStreamReader(input, "UTF-8");
                reader = new BufferedReader(reader);
                char[] buffer = new char[1024];
                for (int n = 0; n >= 0;) {
                    n = reader.read(buffer, 0, buffer.length);
                    if (n > 0)
                        response.append(buffer, 0, n);
                }

                input.close();
                httpConnection.disconnect();
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

        if (response != null) {
            return response.toString();
        } else {
            return "";
        }
    }
    
    //
    // getURLisMeetingRunning() -- return a URL that the client can use to poll for whether the given meeting is running
    //
    public String getURLisMeetingRunning(String meetingID) {
        String base_main = "meetingID=" + urlEncode(meetingID);
        String base_url = BigBlueButtonURL + "api/isMeetingRunning?";
        String checksum ="";
        
        try {
            checksum = DigestUtils.shaHex("isMeetingRunning" + base_main + salt);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        return base_url + base_main + "&checksum=" + checksum;
    }

    //
    // isMeetingRunning() -- check the BigBlueButton server to see if the meeting is running (i.e. there is someone in the meeting)
    //
    public String isMeetingRunning(String meetingID) {
        String base_main = "meetingID=" + urlEncode(meetingID);
        String base_url = BigBlueButtonURL + "api/isMeetingRunning?";
        String checksum ="";
        
        try {
            checksum = DigestUtils.shaHex("isMeetingRunning" + base_main + salt);
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        
        String xml = getURL(base_url + base_main + "&checksum=" + checksum);

        Document doc = null;
        try {
            doc = parseXml(xml);
        } catch (Exception e) {
            e.printStackTrace();
        }

        if (doc.getElementsByTagName("returncode").item(0).getTextContent()
                .trim().equals("SUCCESS")) {
            return doc.getElementsByTagName("running").item(0).getTextContent().trim();
        }
        
        return  "false";
        
    }
    
    //
    // parseXml() -- return a DOM of the XML
    //
    public static Document parseXml(String xml)
            throws ParserConfigurationException, IOException, SAXException {
        DocumentBuilderFactory docFactory = DocumentBuilderFactory
                .newInstance();
        DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
        Document doc = docBuilder.parse(new InputSource(new StringReader(xml)));
        return doc;
    }
    
    //
    // urlEncode() -- URL encode the string
    //
    public static String urlEncode(String s) {  
        try {
            return URLEncoder.encode(s, "UTF-8");
        } catch (Exception e) {
            e.printStackTrace();
        }
        return "";
    }
%>