/*
 * Jitsi, the OpenSource Java VoIP and Instant Messaging client.
 *
 * Copyright @ 2015 Atlassian Pty Ltd
 *
 * 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.java.sip.communicator.impl.gui.main.call;

import java.awt.*;
import java.beans.*;
import java.net.*;
import java.util.*;
import java.util.List;

import javax.swing.*;
import javax.swing.text.*;

import net.java.sip.communicator.impl.gui.*;
import net.java.sip.communicator.plugin.desktoputil.*;
import net.java.sip.communicator.service.protocol.*;
import net.java.sip.communicator.service.protocol.media.*;
import net.java.sip.communicator.util.*;

import org.ice4j.ice.*;
import org.jitsi.service.neomedia.*;
import org.jitsi.service.neomedia.stats.*;
import org.jitsi.service.resources.*;
import org.jitsi.util.*;

import com.explodingpixels.macwidgets.*;
import java.security.cert.*;
import javax.swing.event.*;

/**
 * The frame displaying the statistical information for a telephony conference.
 *
 * @author Vincent Lucas
 * @author Yana Stamcheva
 */
public class CallInfoFrame
    implements CallTitleListener,
               PropertyChangeListener,
               HyperlinkListener
{
    /**
     * The telephony conference to compute and display the statistics of.
     */
    private CallConference callConference;

    /**
     * The call info window.
     */
    private final JDialog callInfoWindow;

    /**
     * The information text pane.
     */
    private final JEditorPane infoTextPane;

    /**
     * The font color.
     */
    private String fontColor;

    /**
     * The resource management service.
     */
    private final ResourceManagementService resources
        = GuiActivator.getResources();

    /**
     * Indicates if the info window has any text to display.
     */
    private boolean hasCallInfo;

    /**
     * Dummy URL to indicate that the certificate should be displayed.
     */
    private final String CERTIFICATE_URL = "jitsi://viewCertificate";

    /**
     * Creates a new frame containing the statistical information for a specific
     * telephony conference.
     *
     * @param callConference the telephony conference to compute and display the
     * statistics of
     */
    public CallInfoFrame(CallConference callConference)
    {
        this.callConference = callConference;

        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setOpaque(false);
        scrollPane.getViewport().setOpaque(false);

        infoTextPane = createGeneralInfoPane();
        Caret caret = infoTextPane.getCaret();
        if (caret instanceof DefaultCaret)
        {
            ((DefaultCaret) caret).setUpdatePolicy(DefaultCaret.NEVER_UPDATE);
        }
        scrollPane.getViewport().add(infoTextPane);

        callInfoWindow
            = createCallInfoWindow(
                GuiActivator.getResources().getI18NString(
                    "service.gui.callinfo.TECHNICAL_CALL_INFO"));

        callInfoWindow.getContentPane().add(scrollPane);

        hasCallInfo = this.constructCallInfo();
    }

    /**
     * Creates different types of windows depending on the operating system.
     *
     * @param title the title of the created window
     */
    private JDialog createCallInfoWindow( String title)
    {
        JDialog callInfoWindow = null;

        if (OSUtils.IS_MAC)
        {
            HudWindow window = new HudWindow();

            JDialog dialog = window.getJDialog();
            dialog.setTitle(title);

            callInfoWindow = window.getJDialog();
            callInfoWindow.setResizable(true);

            fontColor = "FFFFFF";
        }
        else
        {
            SIPCommDialog dialog = new SIPCommDialog(false);

            callInfoWindow = dialog;
            callInfoWindow.setTitle(title);

            fontColor = "000000";
        }

        return callInfoWindow;
    }

    /**
     * Create call info text pane.
     *
     * @return the created call info text pane
     */
    private JEditorPane createGeneralInfoPane()
    {
        JEditorPane infoTextPane = new JEditorPane();

        /*
         * Make JEditorPane respect our default font because we will be using it
         * to just display text.
         */
        infoTextPane.putClientProperty(
                JEditorPane.HONOR_DISPLAY_PROPERTIES,
                true);

        infoTextPane.setOpaque(false);
        infoTextPane.setEditable(false);
        infoTextPane.setContentType("text/html");
        infoTextPane.addHyperlinkListener(this);

        return infoTextPane;
    }

    /**
     * Returns an HTML string corresponding to the given labelText and infoText,
     * that could be easily added to the information text pane.
     *
     * @param labelText the label text that would be shown in bold
     * @param infoText the info text that would be shown in plain text
     * @return the newly constructed HTML string
     */
    private String getLineString(String labelText, String infoText)
    {
        return "<b>" + labelText + "</b> : " + infoText + "<br/>";
    }

    /**
     * Constructs the call info text.
     * @return true if call info could be found, false otherwise
     */
    private boolean constructCallInfo()
    {
        StringBuffer stringBuffer = new StringBuffer();

        stringBuffer.append(
            "<html><body><p align=\"left\">"
                + "<font color=\"" + fontColor + "\" size=\"3\">");

        stringBuffer.append(getLineString(resources.getI18NString(
            "service.gui.callinfo.CALL_INFORMATION"), ""));

        List<Call> calls = callConference.getCalls();
        /*
         * TODO A telephony conference may consist of a single Call with
         * multiple CallPeers but it may as well consist of multiple Calls.
         */
        if (calls.size() <= 0)
        {
            return false;
        }
        else
        {
            Call aCall = calls.get(0);

            stringBuffer.append(
                    getLineString(
                            resources.getI18NString(
                                    "service.gui.callinfo.CALL_IDENTITY"),
                                    aCall.getProtocolProvider().getAccountID()
                                            .getDisplayName()));

            int callPeerCount = callConference.getCallPeerCount();
            if (callPeerCount > 1)
            {
                stringBuffer.append(
                        getLineString(resources.getI18NString(
                                "service.gui.callinfo.PEER_COUNT"),
                                String.valueOf(callPeerCount)));
            }

            boolean isConfFocus = callConference.isConferenceFocus();

            if (isConfFocus)
            {
                stringBuffer.append(getLineString(
                        resources.getI18NString(
                                "service.gui.callinfo.IS_CONFERENCE_FOCUS"),
                        String.valueOf(isConfFocus)));
            }

            TransportProtocol preferredTransport
                = aCall.getProtocolProvider().getTransportProtocol();

            if (preferredTransport != TransportProtocol.UNKNOWN)
                stringBuffer.append(getLineString(
                    resources.getI18NString("service.gui.callinfo.CALL_TRANSPORT"),
                    preferredTransport.toString()));

            final OperationSetTLS opSetTls = aCall.getProtocolProvider()
                    .getOperationSet(OperationSetTLS.class);
            if (opSetTls != null)
            {
                stringBuffer.append(getLineString(
                        resources.getI18NString(
                        "service.gui.callinfo.TLS_PROTOCOL"),
                        opSetTls.getProtocol()));
                stringBuffer.append(getLineString(
                        resources.getI18NString(
                        "service.gui.callinfo.TLS_CIPHER_SUITE"),
                        opSetTls.getCipherSuite()));

                stringBuffer.append("<b><a href=\"")
                    .append(CERTIFICATE_URL)
                    .append("\">")
                    .append(resources.getI18NString(
                            "service.gui.callinfo.VIEW_CERTIFICATE"))
                    .append("</a></b><br/>");
            }

            constructCallPeersInfo(stringBuffer);

            stringBuffer.append("</font></p></body></html>");

            infoTextPane.setText(stringBuffer.toString());
            infoTextPane.revalidate();
            infoTextPane.repaint();

            return true;
        }
    }

    /**
     * Constructs call peers' info.
     *
     * @param stringBuffer the <tt>StringBuffer</tt>, where call peer info will
     * be added
     */
    private void constructCallPeersInfo(StringBuffer stringBuffer)
    {
        for (CallPeer callPeer : callConference.getCallPeers())
        {
            if(callPeer instanceof MediaAwareCallPeer)
            {
                ((MediaAwareCallPeer<?,?,?>) callPeer)
                    .getMediaHandler()
                        .addPropertyChangeListener(this);
            }
            stringBuffer.append("<br/>");
            constructPeerInfo(callPeer, stringBuffer);
        }
    }

    /**
     * Constructs peer info.
     *
     * @param callPeer the <tt>CallPeer</tt>, for which we'll construct the info
     * @param stringBuffer the <tt>StringBuffer</tt>, where call peer info will
     * be added
     */
    private void constructPeerInfo(CallPeer callPeer, StringBuffer stringBuffer)
    {
        stringBuffer.append(getLineString(callPeer.getAddress(), ""));

        if(callPeer.getCallDurationStartTime() !=
                CallPeer.CALL_DURATION_START_TIME_UNKNOWN)
        {
            Date startTime = new Date(callPeer.getCallDurationStartTime());
            stringBuffer.append(getLineString(
                resources.getI18NString("service.gui.callinfo.CALL_DURATION"),
                GuiUtils.formatTime(startTime.getTime(),
                                    System.currentTimeMillis())));
        }

        if(callPeer instanceof MediaAwareCallPeer)
        {
            CallPeerMediaHandler<?> callPeerMediaHandler
                = ((MediaAwareCallPeer<?,?,?>) callPeer).getMediaHandler();

            if(callPeerMediaHandler != null)
            {
                MediaStream mediaStream =
                    callPeerMediaHandler.getStream(MediaType.AUDIO);

                if (mediaStream != null && mediaStream.isStarted())
                {
                    stringBuffer.append("<br/>");
                    stringBuffer.append(getLineString(resources.getI18NString(
                        "service.gui.callinfo.AUDIO_INFO"), ""));

                    this.appendStreamEncryptionMethod(
                            stringBuffer,
                            callPeerMediaHandler,
                            mediaStream,
                            MediaType.AUDIO);

                    constructAudioVideoInfo(
                            callPeerMediaHandler,
                            mediaStream,
                            stringBuffer,
                            MediaType.AUDIO);
                }

                mediaStream = callPeerMediaHandler.getStream(MediaType.VIDEO);

                if (mediaStream != null && mediaStream.isStarted())
                {
                    stringBuffer.append("<br/>");
                    stringBuffer.append(getLineString(resources.getI18NString(
                        "service.gui.callinfo.VIDEO_INFO"), ""));

                    this.appendStreamEncryptionMethod(
                            stringBuffer,
                            callPeerMediaHandler,
                            mediaStream,
                            MediaType.VIDEO);

                    constructAudioVideoInfo(
                            callPeerMediaHandler,
                            mediaStream,
                            stringBuffer,
                            MediaType.VIDEO);
                }

                stringBuffer.append("<br/>");
                // ICE state
                String iceState = callPeerMediaHandler.getICEState();
                if(iceState != null && !iceState.equals("Terminated"))
                {
                    stringBuffer.append(getLineString(
                        resources.getI18NString(
                            "service.gui.callinfo.ICE_STATE"),
                        resources.getI18NString(
                            "service.gui.callinfo.ICE_STATE."
                                + iceState.toUpperCase())));
                }

                stringBuffer.append("<br/>");
                // Total harvesting time.
                long harvestingTime
                    = callPeerMediaHandler.getTotalHarvestingTime();
                if(harvestingTime != 0)
                {
                    stringBuffer.append(getLineString(resources.getI18NString(
                                    "service.gui.callinfo.TOTAL_HARVESTING_TIME"
                                    ),
                                harvestingTime
                                + " "
                                + resources.getI18NString(
                                    "service.gui.callinfo.HARVESTING_MS_FOR")
                                + " "
                                + callPeerMediaHandler.getNbHarvesting()
                                + " "
                                + resources.getI18NString(
                                    "service.gui.callinfo.HARVESTS")));
                }

                // Current harvester time if ICE agent is harvesting.
                String[] harvesterNames =
                {
                    "GoogleTurnCandidateHarvester",
                    "GoogleTurnSSLCandidateHarvester",
                    "HostCandidateHarvester",
                    "JingleNodesHarvester",
                    "StunCandidateHarvester",
                    "TurnCandidateHarvester",
                    "UPNPHarvester"
                };
                for(int i = 0; i < harvesterNames.length; ++i)
                {
                    harvestingTime = callPeerMediaHandler.getHarvestingTime(
                            harvesterNames[i]);
                    if(harvestingTime != 0)
                    {
                        stringBuffer.append(getLineString(
                                    resources.getI18NString(
                                        "service.gui.callinfo.HARVESTING_TIME")
                                    + " " + harvesterNames[i],
                                    harvestingTime
                                    + " "
                                    + resources.getI18NString(
                                        "service.gui.callinfo.HARVESTING_MS_FOR"
                                        )
                                    + " "
                                    + callPeerMediaHandler.getNbHarvesting(
                                        harvesterNames[i])
                                    + " "
                                    + resources.getI18NString(
                                        "service.gui.callinfo.HARVESTS")));
                    }
                }
            }
        }
    }

    /**
     * Constructs audio video peer info.
     *
     * @param callPeerMediaHandler The <tt>CallPeerMadiaHandler</tt> containing
     * the AUDIO/VIDEO stream.
     * @param mediaStream the <tt>MediaStream</tt> that gives us access to
     * audio video info
     * @param stringBuffer the <tt>StringBuffer</tt>, where call peer info will
     * be added
     * @param mediaType The media type used to determine which stream of the
     * media handler must returns it encryption method.
     */
    private void constructAudioVideoInfo(
            CallPeerMediaHandler<?> callPeerMediaHandler,
            MediaStream mediaStream,
            StringBuffer stringBuffer,
            MediaType mediaType)
    {
        MediaStreamStats2 mediaStreamStats
            = mediaStream.getMediaStreamStats();

        if(mediaStreamStats == null)
            return;

        mediaStreamStats.updateStats();

        if(mediaType == MediaType.VIDEO)
        {
            Dimension downloadVideoSize =
                mediaStreamStats.getDownloadVideoSize();
            Dimension uploadVideoSize = mediaStreamStats.getUploadVideoSize();
            // Checks that at least one video stream is active.
            if(downloadVideoSize != null || uploadVideoSize != null)
            {
                stringBuffer.append(
                        getLineString(resources.getI18NString(
                                "service.gui.callinfo.VIDEO_SIZE"),
                            "&darr; "
                            + this.videoSizeToString(downloadVideoSize)
                            + " &uarr; "
                            + this.videoSizeToString(uploadVideoSize)));
            }
            // Otherwise, quit the stats for this video stream.
            else
            {
                return;
            }
        }

        stringBuffer.append(
            getLineString(
                resources.getI18NString("service.gui.callinfo.CODEC"),
                mediaStreamStats.getEncoding()
                + " / " + mediaStreamStats.getEncodingClockRate() + " Hz"));

        boolean displayedIpPort = false;

        // ICE candidate type
        String iceCandidateExtendedType =
            callPeerMediaHandler.getICECandidateExtendedType(
                    mediaType.toString());
        if(iceCandidateExtendedType != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_CANDIDATE_EXTENDED_TYPE"),
                        iceCandidateExtendedType));
            displayedIpPort = true;
        }

        // Local host address
        InetSocketAddress iceLocalHostAddress =
            callPeerMediaHandler.getICELocalHostAddress(mediaType.toString());
        if(iceLocalHostAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_LOCAL_HOST_ADDRESS"),
                    iceLocalHostAddress.getAddress().getHostAddress()
                        + "/" + iceLocalHostAddress.getPort()));
            displayedIpPort = true;
        }

        // Local reflexive address
        InetSocketAddress iceLocalReflexiveAddress =
            callPeerMediaHandler.getICELocalReflexiveAddress(
                    mediaType.toString());
        if(iceLocalReflexiveAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_LOCAL_REFLEXIVE_ADDRESS"),
                    iceLocalReflexiveAddress.getAddress()
                        .getHostAddress()
                        + "/" + iceLocalReflexiveAddress.getPort()));
            displayedIpPort = true;
        }

        // Local relayed address
        InetSocketAddress iceLocalRelayedAddress =
            callPeerMediaHandler.getICELocalRelayedAddress(
                    mediaType.toString());
        if(iceLocalRelayedAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_LOCAL_RELAYED_ADDRESS"),
                    iceLocalRelayedAddress.getAddress()
                        .getHostAddress()
                        + "/" + iceLocalRelayedAddress.getPort()));
            displayedIpPort = true;
        }

        // Remote relayed address
        InetSocketAddress iceRemoteRelayedAddress =
            callPeerMediaHandler.getICERemoteRelayedAddress(
                    mediaType.toString());
        if(iceRemoteRelayedAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_REMOTE_RELAYED_ADDRESS"),
                    iceRemoteRelayedAddress.getAddress()
                        .getHostAddress()
                        + "/" + iceRemoteRelayedAddress.getPort()));
            displayedIpPort = true;
        }

        // Remote reflexive address
        InetSocketAddress iceRemoteReflexiveAddress =
            callPeerMediaHandler.getICERemoteReflexiveAddress(
                    mediaType.toString());
        if(iceRemoteReflexiveAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_REMOTE_REFLEXIVE_ADDRESS"),
                    iceRemoteReflexiveAddress.getAddress()
                        .getHostAddress()
                        + "/" + iceRemoteReflexiveAddress.getPort()));
            displayedIpPort = true;
        }

        // Remote host address
        InetSocketAddress iceRemoteHostAddress =
            callPeerMediaHandler.getICERemoteHostAddress(mediaType.toString());
        if(iceRemoteHostAddress != null)
        {
            stringBuffer.append(getLineString(resources.getI18NString(
                    "service.gui.callinfo.ICE_REMOTE_HOST_ADDRESS"),
                    iceRemoteHostAddress.getAddress().getHostAddress()
                        + "/" + iceRemoteHostAddress.getPort()));
            displayedIpPort = true;
        }

        // If the stream does not use ICE, then show the transport IP/port.
        if(!displayedIpPort)
        {
            stringBuffer.append(
                getLineString(
                    resources.getI18NString("service.gui.callinfo.LOCAL_IP"),
                    mediaStreamStats.getLocalIPAddress()
                    + " / "
                    + String.valueOf(mediaStreamStats.getLocalPort())));

            stringBuffer.append(
                getLineString(
                    resources.getI18NString("service.gui.callinfo.REMOTE_IP"),
                    mediaStreamStats.getRemoteIPAddress()
                    + " / "
                    + String.valueOf(mediaStreamStats.getRemotePort())));
        }


        stringBuffer.append(
            getLineString(
                resources.getI18NString(
                    "service.gui.callinfo.BANDWITH"),
                    "&darr; "
                    + (int) mediaStreamStats.getReceiveStats().getBitrate()/1024
                        + " Kbps "
                    + " &uarr; "
                    + (int) mediaStreamStats.getSendStats().getBitrate()/1024
                        + " Kbps"));

        stringBuffer.append(
            getLineString(
                resources.getI18NString("service.gui.callinfo.LOSS_RATE"),
                    "&darr;"
                    + (int) (mediaStreamStats.getReceiveStats().getLossRate() * 100)
                    + "% &uarr; "
                    + (int) (mediaStreamStats.getSendStats().getLossRate() * 100)
                    + "%"));
        stringBuffer.append(
            getLineString(
                 resources.getI18NString(
                     "service.gui.callinfo.DECODED_WITH_FEC"),
                 String.valueOf(mediaStreamStats.getNbFec())));
        stringBuffer.append(getLineString(
                 resources.getI18NString(
                         "service.gui.callinfo.DISCARDED_PERCENT"),
                 String.valueOf((int)mediaStreamStats.getPercentDiscarded()
                         + "%")));
        stringBuffer.append(getLineString(
            resources.getI18NString("service.gui.callinfo.DISCARDED_TOTAL"),
            String.valueOf(mediaStreamStats.getNbDiscarded())
                + " (" + mediaStreamStats.getNbDiscardedLate() + " late, "
                + mediaStreamStats.getNbDiscardedFull() + " full, "
                + mediaStreamStats.getNbDiscardedShrink() + " shrink, "
                + mediaStreamStats.getNbDiscardedReset() + " reset)"));

        stringBuffer.append(getLineString(
                resources.getI18NString(
                    "service.gui.callinfo.ADAPTIVE_JITTER_BUFFER"),
                    mediaStreamStats.isAdaptiveBufferEnabled()
                            ? "enabled" : "disabled"));
        stringBuffer.append(getLineString(
                resources.getI18NString(
                        "service.gui.callinfo.JITTER_BUFFER_DELAY"),
                "~" + mediaStreamStats.getJitterBufferDelayMs()
                + "ms; currently in queue: "
                + mediaStreamStats.getPacketQueueCountPackets() + "/"
                + mediaStreamStats.getPacketQueueSize() + " packets"));

        long sendRttMs = mediaStreamStats.getSendStats().getRtt();
        long recvRttMs = mediaStreamStats.getReceiveStats().getRtt();
        if(recvRttMs != -1 || sendRttMs != -1)
        {
            stringBuffer.append(
                getLineString(resources.getI18NString(
                        "service.gui.callinfo.RTT"),
                    (recvRttMs != -1 ? "&darr; " + recvRttMs + " ms" : "") +
                    (sendRttMs != -1 ? "&uarr; " + sendRttMs + " ms" : "")));
        }

        stringBuffer.append(
            getLineString(resources.getI18NString(
                    "service.gui.callinfo.JITTER"),
                "&darr; " + (int) mediaStreamStats.getReceiveStats().getJitter()
                + " ms &uarr; "
                + (int) mediaStreamStats.getSendStats().getJitter() + " ms"));
    }

    /**
     * Called when the title of the given CallPanel changes.
     *
     * @param callContainer the <tt>CallContainer</tt>, which title has changed
     */
    public void callTitleChanged(CallPanel callContainer)
    {
        String selectedText = infoTextPane.getSelectedText();

        // If there's a selection do not update call info, otherwise the user
        // would not be able to copy the selected text.
        if (selectedText != null && selectedText.length() > 0)
            return;

        hasCallInfo = this.constructCallInfo();
    }

    /**
     * Shows/hides the corresponding window.
     *
     * @param isVisible <tt>true</tt> to show the window, <tt>false</tt> to
     * hide it
     */
    public void setVisible(boolean isVisible)
    {
        if (isVisible)
        {
            callInfoWindow.pack();
            callInfoWindow.setPreferredSize(new Dimension(300, 450));
            callInfoWindow.setSize(300, 450);
            callInfoWindow.setLocationRelativeTo(null);
        }

        callInfoWindow.setVisible(isVisible);
    }

    /**
     * Indicates if the corresponding window is visible.
     *
     * @return <tt>true</tt> if the window is visible, <tt>false</tt> -
     * otherwise
     */
    public boolean isVisible()
    {
        return callInfoWindow.isVisible();
    }

    /**
     * Indicates if the call info window has any text to display
     *
     * @return <tt>true</tt> if the window contains call info,
     * <tt>false</tt> otherwise
     */
    public boolean hasCallInfo()
    {
        return hasCallInfo;
    }

    /**
     * Disposes the corresponding window.
     */
    public void dispose()
    {
        callInfoWindow.dispose();
    }

    /**
     * Appends to the string buffer the stream encryption method (null, MIKEY,
     * SDES, ZRTP) used for a given media stream (type AUDIO or VIDEO).
     *
     * @param stringBuffer The string buffer containing the call information
     * statistics.
     * @param callPeerMediaHandler The media handler containing the different
     * media streams.
     * @param mediaStream the <tt>MediaStream</tt> that gives us access to
     * audio/video info.
     * @param mediaType The media type used to determine which stream of the
     * media handler must returns it encryption method.
     */
    private void appendStreamEncryptionMethod(
            StringBuffer stringBuffer,
            CallPeerMediaHandler<?> callPeerMediaHandler,
            MediaStream mediaStream,
            MediaType mediaType)
    {
        String transportProtocolString = "";
        StreamConnector.Protocol transportProtocol =
            mediaStream.getTransportProtocol();
        if(transportProtocol != null)
        {
            transportProtocolString = transportProtocol.toString();
        }

        String rtpType;
        SrtpControl srtpControl
            = callPeerMediaHandler.getEncryptionMethod(mediaType);
        // If the stream is secured.
        if(srtpControl != null)
        {
            String info;
            if (srtpControl instanceof ZrtpControl)
            {
                info = "ZRTP " + ((ZrtpControl)srtpControl).getCipherString();
            }
            else
            {
                info = srtpControl.getSrtpControlType().toString();
            }

            rtpType = resources.getI18NString(
                "service.gui.callinfo.MEDIA_STREAM_SRTP")
                + " ("
                + resources.getI18NString(
                    "service.gui.callinfo.KEY_EXCHANGE_PROTOCOL")
                + ": "
                + info
                + ")";
        }
        // If the stream is not secured.
        else
        {
            rtpType = resources.getI18NString(
                            "service.gui.callinfo.MEDIA_STREAM_RTP");
        }
        // Appends the encryption status String.
        stringBuffer.append(getLineString(
                    resources.getI18NString(
                        "service.gui.callinfo.MEDIA_STREAM_TRANSPORT_PROTOCOL"),
                    transportProtocolString + " / " + rtpType));

    }

    /**
     * Listen for ice property change to trigger call info update.
     * @param evt the event for state change.
     */
    public void propertyChange(PropertyChangeEvent evt)
    {
        if(evt.getPropertyName().equals(Agent.PROPERTY_ICE_PROCESSING_STATE))
        {
            callTitleChanged(null);
        }
    }

    /**
     * Converts a video size Dimension into its String representation.
     *
     * @param videoSize The video size Dimension, containing the width and the
     * hieght of the video.
     *
     * @return The String representation of the video width and height, or a
     * String with "Not Available (N.A.)" if the videoSize is null.
     */
    private String videoSizeToString(Dimension videoSize)
    {
        if(videoSize == null)
        {
            return resources.getI18NString("service.gui.callinfo.NA");
        }
        return ((int) videoSize.getWidth()) + " x " + ((int) videoSize.getHeight());
    }

    /**
     * Invoked when user clicks a link in the editor pane.
     * @param e the event
     */
    public void hyperlinkUpdate(HyperlinkEvent e)
    {
        // Handle "View certificate" link
        if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED
                        && CERTIFICATE_URL.equals(e.getDescription()))
        {
            List<Call> calls = callConference.getCalls();
            if (!calls.isEmpty())
            {
                Call aCall = calls.get(0);
                Certificate[] chain = aCall.getProtocolProvider()
                        .getOperationSet(OperationSetTLS.class)
                        .getServerCertificates();

                ViewCertificateFrame certFrame =
                        new ViewCertificateFrame(chain, null,
                            resources.getI18NString(
                            "service.gui.callinfo.TLS_CERTIFICATE_CONTENT"));
                certFrame.setVisible(true);
            }
        }
    }
}