//-------------------------------------------------------------------------
   // FILE: XmlToNativeDomImpl.java
   // PACKAGE: org.astrogrid.ace.utils
   //
   // DATE       AUTHOR    NOTES
   // ----       ------    -----
   // 14/10/02   KEA       Initial prototype
   // 04/12/02   KEA       Revised to deal with new Ace Schema (v.1_0).
   //                      NB this is an interim release.
  // 13/12/02   KEA       Added support for new "Wavelength" XML tag
  //-------------------------------------------------------------------------
  
  
  package org.astrogrid.ace.utils;
  
  import org.w3c.dom.Document;
  import org.w3c.dom.Element;
  import org.w3c.dom.NodeList;
  import org.w3c.dom.Node;
  
  import org.apache.xerces.parsers.DOMParser;
  import org.xml.sax.InputSource;
  
  import java.util.Map;
  import java.util.Iterator;
  import java.util.TreeMap;
  import java.util.Vector;
  
  import java.io.Reader;
  import java.io.Writer;
  
  
  /***
   * <p>DOM-parser based implementation of file format converter for 
   * conversions from Ace XML format to SExtractor native parameter 
   * files.
   *
   * <p>This version uses the Xerces DOM parser;  an alternative 
   * would be to try IBM's xml4j (a progenitor of Xerces but
   * undergoing separate development).
   *
   * <p> In this interim version, the following output catalog vector
   * parameters <strong>are</strong> supported:
   * <ul>
   * <li> MAG_APER(n) </li>
   * <li> MAGERR_APER(n) </li>
   * <li> FLUX_APER(n) </li>
   * <li> FLUXERR_APER(n) </li>
   * </ul>
   *
   * but the following output catalog vector parameters are
   * <strong>not</strong> supported:
   *
   * <ul>
   * <li> VECTOR_SOMFIT(n) </li>
   * <li> VECTOR_ASSOC(n) </li>
   * <li> FLUX_GROWTH(n) </li>
   * <li> VIGNET(m,n) </li>
   * <li> VIGNET_SHIFT(m,n) </li>
   * </ul>
   *
   *
   * <p>See Translator.java for a usage example, and Tester.java 
   * for a run-time test harness.
   * 
   * <p>TO DO:  <ul>
   * <li>Handle <strong>all</strong>SExtractor vector catalog parameters, 
   *  not just a subset.</li>
   * <li>Nicer exception-throwing and handling?</li>
   * </ul>
   *
   *
   * @see org.astrogrid.ace.utils.XmlToNativeIfc
   * @see org.astrogrid.ace.utils.Translator 
   * @see org.astrogrid.ace.utils.Tester 
   * 
   * @author Kona Andrews,
   * <a href="mailto:kea@ast.cam.ac.uk">kea@ast.cam.ac.uk</a>
   * @version 1.0
  */
  public class XmlToNativeDomImpl implements XmlToNativeIfc
  {
  	// Utility variable for calculating vector values for certain
  	// output parameters.
  	//
  	private int numPhotApertures = -1;
  
  	/***
  	 * Dummy constructor - does nothing.
  	 */
  	 public XmlToNativeDomImpl()
  	 {
  	 }
  
  	/***
  	 * Parses ACE XML input into a DOM tree.
  	 * 
  	 * @param xmlIn  A (pre-initialised) reader for the input XML
  	 *
 	 * @return  A Document containing the DOM tree for the input XML.
 	 */
 	 protected Document getDOMTree(Reader inputXML) throws Exception
 	 {
 		DOMParser parser = new DOMParser();
 		try 
 		{
 			parser.setFeature("http://xml.org/sax/features/namespaces", false);
 			parser.setFeature(
 				"http://apache.org/xml/features/dom/include-ignorable-whitespace",
 				false);
 		}
 		catch (Exception e) 
 		{
 			throw new Exception(
 			"\nThis parser cannot process a requested feature: \n"
 			+ e.getMessage());
 		}
 		parser.parse(new InputSource(inputXML));
 		return parser.getDocument();
 	 }
 	
 	/***
 	 * Converts Ace XML input to SExtractor output (configuration
 	 * file *.sex and catalog parameter file *.param).
 	 * 
 	 * Parses the Ace XML input into a DOM Tree, then traverses this
 	 * tree to produce the configuration and catalog parameter files.
 	 * 
 	 * @param xmlIn  A (pre-initialised) reader for the input XML
 	 *
 	 * @param configOutWriter  A (pre-initialised) writer for the output 
 	 *     SExtractor *.sex * file.
 	 *
 	 * @param catalogOutWriter  A (pre-initialised) writer for the output 
 	 *     SExtractor *.param file.
 	 */
 	public void makeNative(Reader xmlIn, Writer configOutWriter, 
 										Writer catalogOutWriter) throws Exception
 	{
 		Document document = getDOMTree(xmlIn);
 		Map configMap = new TreeMap();
 		numPhotApertures = -1;
 
 		configOutWriter.write(
 			"# Generated by org.astrogrid.ace.utils - DOM implementation\n");
 		catalogOutWriter.write(
 			"# Generated by org.astrogrid.ace.utils - DOM implementation\n"
 			+ "#!WARNING! - "
 			+ "This interim release does not support any vector parameters\n"	
 			+ "#   except MAG_APER, MAG_APERERR, FLUX_APER AND FLUX_APERERR."
 			);
 
 		// Get all children of the root element (AceInputDoc) for processing
 		//
 		NodeList nodeList = (document.getDocumentElement()).getChildNodes();
 		for (int i = 0; i < nodeList.getLength(); i++) 
 		{
 			if (nodeList.item(i).getNodeType() == Node.ELEMENT_NODE) 
 			{
 				Element paramNode = (Element)(nodeList.item(i));
 				
             String tagName = paramNode.getTagName();
 
             // Check if we have a catalog parameter
 				//
             if ( tagName.equals("OUTPUT_COLUMNS") )
 				{
 					doCatalogParameter(paramNode, document.getDocumentElement(),
 							catalogOutWriter);
 				}
 				// Check if we have an ignorable command-line parameter 
 				//
             else if ( !(tagName.equals("ImageToCatalog")) && 
 	                   !(tagName.equals("ImageToMeasure")) &&
 							 !(tagName.equals("Wavelength")) )
 				{
 					// Not command-line param, so have a config parameter
 					// See if this is a multi-argument parameter
 					//
 					NodeList args = 
 						paramNode.getElementsByTagName("arg");
 
 					if (args.getLength() == 0) 
 					{
 						throw new Exception("Error - missing <arg> for parameter "
 								+ paramNode.getTagName());
 					}
 					
 					String tagString = 
 						args.item(0).getFirstChild().getNodeValue();
 
 					for (int j = 1; j < args.getLength(); j++) 
 					{
 						tagString = 
 							tagString + ", " + 
 							args.item(j).getFirstChild().getNodeValue();
 					}
 					configMap.put(paramNode.getTagName(),tagString);
 				}
 			}
 		}
 		// Now convert config parameters to native format 
 		//   (catalog parameters all dealt with already).
 
 		// First of all, get length of longest keyword (for pretty-printing)
 		//
 		int maxLen = 0;
 		Iterator iterator;
 		for (iterator = configMap.entrySet().iterator(); iterator.hasNext(); ) 
 		{
 			Map.Entry me = (Map.Entry)iterator.next();
 			int len = ((String)me.getKey()).length();
 			if (maxLen < len) 
 			{
 				maxLen = len;
 			}
       }
 
 		// Now write all keywords/values to output in native format
 		//
 		for (iterator = configMap.entrySet().iterator(); iterator.hasNext(); ) 
 		{
 			Map.Entry me = (Map.Entry)iterator.next();
 			String tagname = (String)me.getKey();
 			String value = (String)me.getValue();
 
 			int numSpaces = maxLen - tagname.length();
 
 			// Write tag name and pretty-printing spaces
 			configOutWriter.write(tagname + "   ");
 			//System.out.print(tagname + "   ");
 			
 			for (int j = 0; j < numSpaces; j++) 
 			{
 				configOutWriter.write(" ");
 				//System.out.print(" ");
 			}
 
 			// Booleans are a special case (native format uses Y/N)
 			String paramVal = value.trim();
 			if (paramVal.equalsIgnoreCase("true")) 
 			{
 				configOutWriter.write("Y" + "\n");
 				//System.out.print("Y" + "\n");
 			}
 			else if (paramVal.equalsIgnoreCase("false")) 
 			{
 				configOutWriter.write("N" + "\n");
 				//System.out.print("N" + "\n");
 			}
 			else 
 			{
 				// All else than boolean parameters
 				configOutWriter.write(value + "\n");
 				//System.out.print(value + "\n");
 			}
 		}
 	}
 
 
 	protected void doCatalogParameter(Element paramNode, Element rootNode,
 											 Writer catalogOutWriter) throws Exception
 
 	/***
 	 * Traverses a DOM ELement node containing an Ace XML catalog 
 	 * parameter and writes the equivalent native catalog parameter 
 	 * to the * SExtractor catalog parameter file (*.param).
 	 *
 	 * @param element  The DOM element containing the Ace catalog parameter.
 	 *
 	 * @param element  The DOM element that is the root of the input
 	 * document.
 	 *
 	 * @param catalogOutWriter  A (pre-initialised) writer for the output 
 	 *     SExtractor *.param file.
 	 *
 	 * @throws Exception if inconsistencies between configuration and
 	 * catalog parameters are encountered.
 	 */
 	{	
 		String tagName = paramNode.getTagName();
 		NodeList args = paramNode.getElementsByTagName("arg");
 		for (int i = 0; i < args.getLength(); i++) 
 		{
 			String tagname = args.item(i).getFirstChild().getNodeValue();
 
 			// Check for currently unsupported keyword names (vector keywords)
 			// 
 			if ( (tagname.equals("FLUX_APER")) ||
 				  (tagname.equals("FLUXERR_APER")) ||
 				  (tagname.equals("MAG_APER")) ||
 				  (tagname.equals("MAGERR_APER")) )
 			{
 				// Currently-supported vector parameters
 				// Vector value of these is no. of elements in PHOT_APERTURES
 				//
 				if (numPhotApertures == -1) // Not set yet
 				{
 					NodeList photAps =
 						rootNode.getElementsByTagName("PHOT_APERTURES");
 					if (photAps.getLength() != 1)
 					{
 						throw new Exception("Error - unexpected number (" 
 							+ Integer.toString(photAps.getLength()) 
 							+ ") of PHOT_APERTURE tags (expected exactly 1, "
 							+ "since output tag " + tagname + " is present.");
 					}
 					else 
 					{
 						NodeList photArgs = 
 							((Element)photAps.item(0)).getElementsByTagName("arg");
 						numPhotApertures = photArgs.getLength();
 					}
 				}
 				catalogOutWriter.write(tagname + "(" + 
 						Integer.toString(numPhotApertures) + ")\n");
 
 			}
 
 			else if ( (tagname.equals("VECTOR_SOMFIT")) ||
 				  (tagname.equals("VECTOR_ASSOC")) ||
 				  (tagname.equals("FLUX_GROWTH")) ||
 				  (tagname.equals("VIGNET")) ||
 				  (tagname.equals("VIGNET_SHIFT")) ) 
 
 			{
 				// Not currently supported vector parameters
 				//
 				catalogOutWriter.write("#!WARNING! Vector parameter \"" + tagname 
 					+ "\" is not supported in this release!\n");
 			}
 			else 
 			{
 				catalogOutWriter.write(tagname + "\n");
 			}
 		}
 	}
 }
 //-------------------------------------------------------------------------