content: /**
   * ﻿Copyright (C) 2007 - 2019 52°North Initiative for Geospatial Open Source
   * Software GmbH
   *
   * This program is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 as published
   * by the Free Software Foundation.
   *
   * If the program is linked with libraries which are licensed under one of
   * the following licenses, the combination of the program with the linked
   * library is not considered a "derivative work" of the program:
   *
   *       • Apache License, version 2.0
   *       • Apache Software License, version 1.0
   *       • GNU Lesser General Public License, version 3
   *       • Mozilla Public License, versions 1.0, 1.1 and 2.0
   *       • Common Development and Distribution License (CDDL), version 1.0
   *
   * Therefore the distribution of the program linked with libraries licensed
   * under the aforementioned licenses, is permitted by the copyright holders
   * if the distribution is compliant with both the GNU General Public
   * License version 2 and the aforementioned licenses.
   *
   * As an exception to the terms of the GPL, you may copy, modify,
   * propagate, and distribute a work formed by combining 52°North WPS
   * GeoTools Modules with the Eclipse Libraries, or a work derivative of
   * such a combination, even if such copying, modification, propagation, or
   * distribution would otherwise violate the terms of the GPL. Nothing in
   * this exception exempts you from complying with the GPL in all respects
   * for all of the code used other than the Eclipse Libraries. You may
   * include this exception and its grant of permissions when you distribute
   * 52°North WPS GeoTools Modules. Inclusion of this notice with such a
   * distribution constitutes a grant of such permissions. If you do not wish
   * to grant these permissions, remove this paragraph from your
   * distribution. "52°North WPS GeoTools Modules" means the 52°North WPS
   * modules using GeoTools functionality - software licensed under version 2
   * or any later version of the GPL, or a work based on such software and
   * licensed under the GPL. "Eclipse Libraries" means Eclipse Modeling
   * Framework Project and XML Schema Definition software distributed by the
   * Eclipse Foundation and licensed under the Eclipse Public License Version
   * 1.0 ("EPL"), or a work based on such software and licensed under the EPL.
   *
   * This program 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 General
   * Public License for more details.
   */
  package org.n52.wps.io.datahandler.generator;
  
  import java.io.ByteArrayInputStream;
  import java.io.IOException;
  import java.io.InputStream;
  
  import javax.xml.parsers.DocumentBuilderFactory;
  import javax.xml.parsers.ParserConfigurationException;
  import javax.xml.transform.TransformerException;
  
  import org.apache.commons.httpclient.HttpException;
  import org.geotools.data.simple.SimpleFeatureCollection;
  import org.n52.wps.PropertyDocument.Property;
  import org.n52.wps.commons.WPSConfig;
  import org.n52.wps.commons.XMLUtil;
  import org.n52.wps.io.data.IData;
  import org.n52.wps.io.data.binding.complex.GTVectorDataBinding;
  import org.n52.wps.io.datahandler.generator.mapserver.MSMapfileBinding;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  
  /**
   * Generator for saving results of a WPS Process in an UMNMapserver. Right now
   * this generator only supports publishing results over an Mapserver-WMS. As
   * input this generator right now only supports GTVectorDataBinding. As template
   * for this class served the GeoserverWMSGenerator.
   * 
   * @author Jacob Mendt
   * 
   * @TODO Support more inputs (shapefile, raster)
   * @TODO Generator for WCS and WFS
   */
  public class MapserverWMSGenerator extends AbstractGenerator {
  
  	private String mapfile;
  	private String workspace;
  	private String shapefileRepository;
  	private String wmsUrl;
  	
  	private static Logger LOGGER = LoggerFactory.getLogger(MapserverWMSGenerator.class);
  
  	/**
  	 * Initialize a new MapserverWMSGenerator object. Parse the parameter
  	 * Mapserver_workspace, Mapserver_mapfile, Mapserver_dataRepository and
  	 * Mapserver_wmsUrl from the config.xml of the WPS.
  	 */
  	public MapserverWMSGenerator() {
  
  		super();
  
  		this.supportedIDataTypes.add(GTVectorDataBinding.class);
  
  		Property[] properties = WPSConfig.getInstance()
  				.getPropertiesForGeneratorClass(this.getClass().getName());
  
  		for (Property property : properties) {
  			if (property.getName().equalsIgnoreCase("Mapserver_workspace")) {
  				workspace = property.getStringValue();
  			}
  			if (property.getName().equalsIgnoreCase("Mapserver_mapfile")) {
  				mapfile = property.getStringValue();
  			}
  			if (property.getName().equalsIgnoreCase("Mapserver_dataRepository")) {
  				shapefileRepository = property.getStringValue();
  			}
  			if (property.getName().equalsIgnoreCase("Mapserver_wmsUrl")) {
  				wmsUrl = property.getStringValue();
  			}
  		}
  		for (String supportedFormat : supportedFormats) {
  			if (supportedFormat.equals("text/xml")) {
  				supportedFormats.remove(supportedFormat);
  			}
  		}
  	}
  
  	@Override
  	public InputStream generateStream(IData data, String mimeType, String schema)
  			throws IOException {
  
  		InputStream stream = null;	
  		try {
  			Document doc = storeLayer(data);			
  			String xmlString = XMLUtil.nodeToString(doc);			
  			stream = new ByteArrayInputStream(xmlString.getBytes("UTF-8"));			
  	    } catch(TransformerException ex){
  	    	LOGGER.error("Error generating MapServer WMS output. Reason: " + ex);
  	    	throw new RuntimeException("Error generating MapServer WMS output. Reason: " + ex);
  	    } catch (IOException e) {
  	    	LOGGER.error("Error generating MapServer WMS output. Reason: " + e);
  	    	throw new RuntimeException("Error generating MapServer WMS output. Reason: " + e);
  		} catch (ParserConfigurationException e) {
  	    	LOGGER.error("Error generating MapServer WMS output. Reason: " + e);
  			throw new RuntimeException("Error generating MapServer WMS output. Reason: " + e);
  		}	
  		return stream;
  	}
  
  	/**
  	 * Stores the input data as an layer in the mapserver and creates an
  	 * response document.
  	 * 
  	 * @param coll
  	 *            IData has to be instanceof GTVectorDataBinding
  	 * 
  	 * @return Document XML response document.
  	 * 
  	 * @throws HttpException
  	 * @throws IOException
  	 * @throws ParserConfigurationException
  	 */
  	private Document storeLayer(IData coll) throws HttpException, IOException,
  			ParserConfigurationException {
  
  		// tests if the mapscript.jar was loaded correctly
  		try {
  			//MapserverProperties.getInstance().testMapscriptLibrary();
  			LOGGER.info("Mapscript is running correctly");
  		} catch (Exception e){
  			e.printStackTrace();
  			LOGGER.warn("Mapscript isn't running correctly");
  			return null;
  		} 
  		
  		// adds the IData to the mapserver.
  		String wmsLayerName = "";
  		if (coll instanceof GTVectorDataBinding) {
  			GTVectorDataBinding gtData = (GTVectorDataBinding) coll;
  			SimpleFeatureCollection ftColl = (SimpleFeatureCollection) gtData.getPayload();
  			wmsLayerName = MSMapfileBinding.getInstance().addFeatureCollectionToMapfile(ftColl, workspace,
  					mapfile, shapefileRepository);
  			LOGGER.info("Layer was added to the mapfile");
  			System.gc();
  		}
  
  		// creates the response document
  		String capabilitiesLink = wmsUrl + "?Service=WMS&Request=GetCapabilities";
  		Document doc = createXML(wmsLayerName, capabilitiesLink);
  		LOGGER.info("Capabilities document was generated.");
  		
  		return doc;
  
  	}
  
  	/**
  	 * Creates an response xml, which contains the layer name, the resource link
  	 * and a getCapabilities request for the publishing service.
  	 * 
  	 * @param layerName
  	 *            Name of the layer which was added to the mapserver.
  	 * @param resourceLink
  	 *            Link to the resource (layer) which was added to the mapserver.
  	 * @param getCapabilitiesLink
  	 *            GetCapabilties request to the publishing service.
  	 * 
  	 * @return Document XML response document.
  	 * 
  	 * @throws ParserConfigurationException
  	 */
  	private Document createXML(String layerName, String getCapabilitiesLink)
  			throws ParserConfigurationException {
  		DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
  		Document doc = factory.newDocumentBuilder().newDocument();
  
  		Element root = doc.createElement("OWSResponse");
  		root.setAttribute("type", "WMS");
  
  		Element resourceIDElement = doc.createElement("ResourceID");
  		resourceIDElement.appendChild(doc.createTextNode(layerName));
  		root.appendChild(resourceIDElement);
  
  		Element getCapabilitiesLinkElement = doc
  				.createElement("GetCapabilitiesLink");
  		getCapabilitiesLinkElement.appendChild(doc
  				.createTextNode(getCapabilitiesLink));
  		root.appendChild(getCapabilitiesLinkElement);
  		/*
  		 * Element directResourceLinkElement =
  		 * doc.createElement("DirectResourceLink");
  		 * directResourceLinkElement.appendChild
  		 * (doc.createTextNode(getMapRequest));
  		 * root.appendChild(directResourceLinkElement);
  		 */
  		doc.appendChild(root);
  
  		return doc;
  	}
  
  }
  