Application: gvSIG desktop

package org.gvsig.remoteClient.wms;

import java.io.ByteArrayInputStream;

import java.io.DataInputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.StringReader;

import java.net.MalformedURLException;

import java.net.URL;

import java.net.URLConnection;

import java.nio.ByteBuffer;

import java.nio.channels.FileChannel;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.TreeMap;

import java.util.Vector;

import org.gvsig.remoteClient.exceptions.ServerErrorException;

import org.gvsig.remoteClient.exceptions.WMSException;

import org.gvsig.remoteClient.taskplanning.retrieving.RequestManager;

import org.gvsig.remoteClient.taskplanning.retrieving.RetrieveEvent;

import org.gvsig.remoteClient.taskplanning.retrieving.RetrieveListener;

import org.gvsig.remoteClient.taskplanning.retrieving.URLRequest;

import org.gvsig.remoteClient.taskplanning.retrieving.URLRetrieveTask;

import org.gvsig.remoteClient.utils.CapabilitiesTags;

import org.gvsig.remoteClient.utils.ExceptionTags;

import org.gvsig.remoteClient.utils.Utilities;

import org.kxml2.io.KXmlParser;

import org.xmlpull.v1.XmlPullParserException;

import com.iver.andami.PluginServices;

/**

 * <p> Abstract class that represents handlers to comunicate via WMS protocol.

 * </p>

 * 

 */

public abstract class WMSProtocolHandler {

        /**

         * Encoding used to parse different xml documents.

         */

        protected String encoding = "UTF-8";

        /**

         * procotol handler name

         */

    protected String name;

    /**

     * protocol handler version

     */

    protected String version;

    /**

     * host of the WMS to connect

     */

    protected String host;

    /**

     * port number of the comunication channel of the WMS to connect

     */

    protected String port;    

    /**

     * WMS metadata

     */

    protected ServiceInformation serviceInfo;

    public TreeMap layers;

    public WMSLayer rootLayer;

    public Vector srs;

        private URLRequest capabilitiesRequest, mapRequest, featureInfo;

    /**

     * The listener that a driver must implement to receive the events.

     */

    private WMSEventListener theListener;

    /**

     * Listener for the asynchronous getCapabilities requests

     */

    private RetrieveListener getCapabilitiesListener = new RetrieveListener() {

                public void transferEventReceived(RetrieveEvent event) {

                        int type = event.getType();

                        if (type == RetrieveEvent.REQUEST_FINISHED) {

                                System.out.println("parsing "+capabilitiesRequest.getFileName());

                                parse(new File(capabilitiesRequest.getFileName()));

                        }

                        if (theListener!=null) {

                                theListener.newEvent(WMSEventListener.CAPABILITIES, event);

                        }

                }

    } ,

    /**

     * Listener for the asynchronous getMap requests

     */

    getMapListener = new RetrieveListener() {

                public void transferEventReceived(RetrieveEvent event) {

                        int type = event.getType();

                }

    } ,

    getFeatureInfoListener = new RetrieveListener() {

                public void transferEventReceived(RetrieveEvent event) {

                        int type = event.getType();

                }};

    /**

     * parses the data retrieved by the WMS in XML format. 

     * It will be mostly the WMS Capabilities, but the implementation

     * will be placed in the handler implementing certain version of the protocol.

     * 

     */

    public abstract void parse(File f) ;

    public String getName() {        

            return name;

    } 

    public String getVersion() {        

            return version;

    }    

    public ServiceInformation getServiceInformation() {        

        return serviceInfo;

    }  

    public String getHost ()

    {

            return host;

    }

    public void setHost(String _host)

    {

            host = _host;

    }

    public String getPort()

    {

            return port;

    }

    public void setPort(String _port)

    {

            port = _port;

    }

    /**

         * <p>Builds a GetCapabilities request that is sent to the WMS

         * the response will be parsed to extract the data needed by the

         * WMS client</p>

         * @param override, if true the previous downloaded data will be overridden

         */

    public void getCapabilities(WMSStatus status, boolean override)

    {                

                try

                {

                        //request = new URL(buildCapabilitiesRequest(status));

                        capabilitiesRequest = buildCapabilitiesRequest(status);

                        capabilitiesRequest.setFileName("wmsCapabilities");

                        if (override)

                                RequestManager.getInstance().removeURLRequest(capabilitiesRequest);

                        capabilitiesRequest = RequestManager.getInstance().addURLRequest(capabilitiesRequest, getCapabilitiesListener);

            } catch(Exception e)

                {

                        //TODO

                        e.printStackTrace();

                }

    }

    /**

     * <p>It will send a GetFeatureInfo request to the WMS

     * Parsing the response and redirecting the info to the WMS client</p>

     */

    public String getFeatureInfo(WMSStatus status, int x, int y, int featureCount)

    {

            URL request = null;

            StringBuffer output = new StringBuffer();

            String outputFormat = new String();

            String ServiceException = "ServiceExceptionReport";                        

            StringBuffer sb = new StringBuffer();

            sb.append("<?xml version=\"1.0\" encoding=\"ISO-8859-1\"?>");

                try

                {

                        //TODO:

                        //pass this buildXXXRequest to the WMSProtocolHandlerXXX: The request can depend on the WMS version.

                        request = new URL(buildGetFeatureInfoRequest(status, x, y));

                        //TODO:

                        //see which output format is being requested.                                         

                }

                catch(Exception e)

                {

                        e.printStackTrace();

                        return "";

                }

            try

            {                                

                    System.out.println(request.toString());          

                    byte[] buffer = new byte[1024*256];                    

                    DataInputStream is = new DataInputStream(request.openStream());                    

                    outputFormat = request.openConnection().getContentType();

                    for (int i = is.read(buffer); i>0; i = is.read(buffer))

                    {

                            String str = new String(buffer,0,i);

                            output.append(str);                    

                    }

                    is.close();

                    if ( (outputFormat == null) || (outputFormat.indexOf("xml") != -1)

                                    ||output.toString().toLowerCase().startsWith("<?xml")

                                    ||(outputFormat.indexOf("gml") != -1))

                    {

                            int tag;

                            KXmlParser kxmlParser = null;

                            kxmlParser = new KXmlParser();            

                            kxmlParser.setInput(new StringReader(output.toString()));

                            tag = kxmlParser.nextTag();           

                            if (kxmlParser.getName().compareTo(ServiceException)==0)

                                {

                                    sb.append("<INFO>").append(parseException( output.toString().getBytes())).append("</INFO>");

                                    return sb.toString();                                                                        

                                }

                                else if (kxmlParser.getName().compareToIgnoreCase("ERROR")==0)

                                {

                                        return output.toString();

                                }

                                else                

                                {

                                        return output.toString();                

                                }

                    }

                    else

                    {

                            sb.append("<INFO>").append(PluginServices.getText(this, "info_format_not_supported")).append("</INFO>");

                            return sb.toString();

                    }

                }

            catch(XmlPullParserException parserEx)

            {

                    if (output.toString().toLowerCase().indexOf("xml") != -1)

                    {

                            return output.toString().trim();

                    }

                    else

                    {

                               sb.append("<INFO>").append(PluginServices.getText(this, "info_format_not_supported")).append("</INFO>");

                        return sb.toString();

                    }

            }

            catch(Exception e)

            {

                    e.printStackTrace();

                    sb.append("<INFO>").append(PluginServices.getText(this, "info_format_not_supported")).append("</INFO>");

                    return sb.toString();

            }

    }

    public File getMap(WMSStatus status) throws ServerErrorException, WMSException

    {        

            URL request = null;

                try

                {

                        //TODO:

                        //pass this buildXXXRequest to the WMSProtocolHandlerXXX: The request can depend on the WMS version.

                        request = new URL(buildMapRequest(status));

            File f = com.iver.andami.Utilities.downloadFile(request, "wmsGetMap");                                        

            if (Utilities.isTextFile(f)) {

                            FileInputStream fis = new FileInputStream(f);

                            FileChannel fc = fis.getChannel();

                            byte[] data = new byte[(int)fc.size()];   // fc.size returns the size of the file which backs the channel

                            ByteBuffer bb = ByteBuffer.wrap(data);

                            fc.read(bb);

                            WMSException wmsEx = null;

                    String exceptionMessage = parseException(data);

                if (exceptionMessage==null)

                {

                         String error = new String(data);

                        int pos = error.indexOf("<?xml");

                        if (pos!= -1)

                        {

                                String xml = error.substring(pos,error.length());

                                exceptionMessage = parseException(xml.getBytes());

                        }               

                    if (exceptionMessage == null)

                            exceptionMessage = new String(data);

                }

                     wmsEx = new WMSException(exceptionMessage);

                    wmsEx.setWMSMessage(new String(data));

                    // Since it is an error file, It must be deleted from the cache

                    com.iver.andami.Utilities.removeURL(request);

                throw wmsEx;

            }

                        return f;                    

                }

                catch(IOException e)

                {

                        e.printStackTrace();

            throw new ServerErrorException();

                }

    } 

    /* (non-Javadoc)

     * @see org.gvsig.remoteClient.wms.WMSProtocolHandler#parseException(byte[])

     */

    protected String parseException(byte[] data) {

        ArrayList errors = new ArrayList();

        KXmlParser kxmlParser = new KXmlParser();

        try

        {

            kxmlParser.setInput(new ByteArrayInputStream(data), encoding);        

            kxmlParser.nextTag();

            int tag;

            if ( kxmlParser.getEventType() != KXmlParser.END_DOCUMENT ) 

            { 

                kxmlParser.require(KXmlParser.START_TAG, null, ExceptionTags.EXCEPTION_ROOT);             

                tag = kxmlParser.nextTag();

                 while(tag != KXmlParser.END_DOCUMENT)

                 {

                     switch(tag)

                     {

                        case KXmlParser.START_TAG:

                            if (kxmlParser.getName().compareTo(ExceptionTags.SERVICE_EXCEPTION)==0){

                                String errorCode = kxmlParser.getAttributeValue("", ExceptionTags.CODE);

                                errorCode = (errorCode != null) ? "["+errorCode+"] " : "";

                                String errorMessage = kxmlParser.nextText();

                                errors.add(errorCode+errorMessage);

                            }

                            break;

                        case KXmlParser.END_TAG:                            

                            break;

                     }

                     tag = kxmlParser.nextTag();

                 }

                 //kxmlParser.require(KXmlParser.END_DOCUMENT, null, null);

            }

        }

        catch(XmlPullParserException parser_ex){ 

            parser_ex.printStackTrace();

        }

        catch (IOException ioe) {           

            ioe.printStackTrace();            

        }

        String message = errors.size()>0? "" : null;

        for (int i = 0; i < errors.size(); i++) {

            message += (String) errors.get(i)+"\n";

        }

        return message;

    }

    /**

     * Builds the GetCapabilitiesRequest according to the OGC WMS Specifications

     * without a VERSION, to get the highest version than a WMS supports.

     */

    public static String buildCapabilitiesSuitableVersionRequest(String _host, String _version)

    {

                String req = new String();                

        String symbol = getSymbol(_host);

        req = req + _host + symbol + "REQUEST=GetCapabilities&SERVICE=WMS&";                

        if((_version != null) && (_version.length()>0 ))

        {

                req += ("&VERSION=" + _version);

        }

                req += ("&EXCEPTIONS=XML");

                return req;           

    }

    /**

     * Builds the GetCapabilitiesRequest according to the OGC WMS Specifications

     * @param WMSStatus

     * @throws MalformedURLException 

     */

    private URLRequest buildCapabilitiesRequest(WMSStatus status) throws MalformedURLException

    {

                URLRequest req = new URLRequest();

                String symbol = null;

                StringBuffer u = new StringBuffer();

                String onlineResource;

                if (status == null || status.getOnlineResource() == null)

                        onlineResource = getHost();

                else 

                        onlineResource = status.getOnlineResource();

                u.append(onlineResource).

                  append(getSymbol(onlineResource)).

                  append("REQUEST=GetCapabilities&SERVICE=WMS&").

                  append("VERSION=").append(getVersion()).append("&EXCEPTIONS=XML");

                URL url = new URL(u.toString());

                req.setHost(url.getHost());

                req.setRequestType(URLRequest.GET);

                req.setProtocol(URLRequest.HTTP);

                req.setFile(url.getFile());

                int myPort = url.getPort();

                if (myPort != -1 && myPort != 80 )

                        req.setPort(myPort);

                return req;

    }

    /**

     * Builds the GetFeatureInfoRequest according to the OGC WMS Specifications

     */

    private String buildGetFeatureInfoRequest(WMSStatus status, int x, int y)

    {

                StringBuffer req = new StringBuffer();

                String symbol = null;

                String onlineResource;

                if (status.getOnlineResource() == null)

                        onlineResource = getHost();

                else 

                        onlineResource = status.getOnlineResource();

                symbol = getSymbol(onlineResource);

                req.append(onlineResource).append(symbol).append("REQUEST=GetFeatureInfo&SERVICE=WMS&");

                req.append("QUERY_LAYERS=").append(Utilities.Vector2CS(status.getLayerNames())); 

                req.append("&VERSION=").append(getVersion()).append("&INFO_FORMAT=application/vnd.ogc.gml&");

                req.append(getPartialQuery(status)).append("&x="+x + "&y="+y);

       if (status.getExceptionFormat() != null) {

            req.append("&EXCEPTIONS=" + status.getExceptionFormat());

        } else {

            req.append("&EXCEPTIONS=XML");

        }

                return req.toString().replaceAll(" ", "%20");

    }    

    /**

     * Builds the GetMapRequest according to the OGC WMS Specifications

     */

    private String buildMapRequest(WMSStatus status)

    { 

                StringBuffer req = new StringBuffer();

                String symbol = null;

                String onlineResource = null;

                if (status.getOnlineResource() == null)

                        onlineResource = getHost();

                else 

                        onlineResource = status.getOnlineResource();

                symbol = getSymbol(onlineResource);

                req.append(onlineResource + symbol + "REQUEST=GetMap&SERVICE=WMS&VERSION=").append(getVersion()).append("&");

                req.append(getPartialQuery(status));

        if (status.getExceptionFormat() != null) {

            req.append("&EXCEPTIONS=" + status.getExceptionFormat());

        } else {

            req.append("&EXCEPTIONS=XML");

        }

                return req.toString().replaceAll(" ", "%20");

    }

    /**

     * Just for not repeat code. Gets the correct separator according to the server URL

     * @param h

     * @return

     */

    private static String getSymbol(String h) {

        String symbol;

        if (h.indexOf("?")==-1) 

            symbol = "?";

        else if (h.indexOf("?")!=h.length()-1)

            symbol = "&";

        else

            symbol = "";

        return symbol;

    }

    /**

     * Gets the part of the OGC request that share GetMap and GetFeatureInfo

     * @return String request

     */

    public String getPartialQuery(WMSStatus status)

    {            

        StringBuffer req = new StringBuffer();

        req.append("LAYERS=" + Utilities.Vector2CS(status.getLayerNames()))

           .append("&SRS=" + status.getSrs())

           .append("&BBOX=" + status.getExtent().getMinX()+ "," )

           .append(status.getExtent().getMinY()+ ",")

           .append(status.getExtent().getMaxX()+ ",")

           .append(status.getExtent().getMaxY())

           .append("&WIDTH=" + status.getWidth())

           .append("&HEIGHT=" + status.getHeight())

           .append("&FORMAT=" + status.getFormat())

           .append("&STYLES=");

        Vector v = status.getStyles();

        if (v!=null && v.size()>0)

                req.append(Utilities.Vector2CS(v)); 

        v = status.getDimensions();

        if (v!=null && v.size()>0)

            req.append("&" + Utilities.Vector2URLParamString(v));

        if (status.getTransparency()) {

            req.append("&TRANSPARENT=TRUE");

        }

        return req.toString();

    }

    public void close() {        

        // your code here

    } 

    /**

     * Inner class that represents the description of the WMS metadata.

     * The first part of the capabilities will return the service information

     * from the WMS, this class will hold this information. 

     * 

     */

    public class ServiceInformation {

        public String online_resource = null;

        /*public String map_online_resource = null;

        public String feature_online_resource = null;*/

        public String version;

        public String name;

        public String scope;

        public String title;

        public String abstr;

        public String keywords;

        public String fees;

        public String operationsInfo;

        public String personname;

        public String organization;

        public String function;

        public String addresstype;

        public String address;

        public String place;

        public String province;

        public String postcode;

        public String country;

        public String phone;

        public String fax;

        public String email;

        public Vector formats;

        public HashMap operations; // operations that WMS supports

        public ServiceInformation()

        {          

            version = new String();

            name = new String();

            scope = new String();

            title = new String();

            abstr = new String();

            keywords = new String();

            fees = new String();

            operationsInfo = new String();

            personname = new String();

            organization = new String();

            function = new String();

            addresstype = new String();

            address = new String();

            place = new String();

            province = new String();

            postcode = new String();

            country = new String();

            phone = new String();

            fax = new String();

            email = new String();

            formats = new Vector();               

            operations = new HashMap();            

        }

        public boolean isQueryable()

        {

                if (operations.keySet().contains( CapabilitiesTags.GETFEATUREINFO ))

                        return true;

                else

                        return false;

        }

     }

        public void setListener(WMSEventListener listener) {

                if (listener!=null)

                        this.theListener = listener;

        }

        public void cancel(int opCode) {

                URLRequest myUrlReq;

                RetrieveListener myListener;

                switch (opCode) {

                case WMSClient.GET_CAPABILITIES:

                        myUrlReq = capabilitiesRequest;

                        myListener = getCapabilitiesListener;

                        break;

                case WMSClient.GET_MAP:

                        myUrlReq = mapRequest;

                        myListener = getMapListener;

                        break;

                case WMSClient.GET_FEATURE_INFO:

                        myUrlReq = featureInfo;

                        myListener = getFeatureInfoListener;

                        break;

                default:

                        System.err.println("[RemoteClients:WMSProtocolHandler] cancelling an unknown operation");

                        return;

                }

                myUrlReq.removeRetrieveListener(myListener);

        }   

 }