//License: GPL. Copyright 2007 by Immanuel Scholz and others
package org.openstreetmap.josm.io;

import static org.openstreetmap.josm.tools.I18n.tr;

import java.io.IOException;
import java.io.StringReader;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParserFactory;

import org.openstreetmap.josm.data.osm.Node;
import org.openstreetmap.josm.data.osm.OsmPrimitive;
import org.openstreetmap.josm.data.osm.Relation;
import org.openstreetmap.josm.data.osm.Way;
import org.openstreetmap.josm.data.osm.visitor.AbstractVisitor;
import org.openstreetmap.josm.gui.PleaseWaitDialog;
import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;

/**
 */
public class DiffResultReader extends AbstractVisitor {

    /**
     * mapping from old id to new id/version
     */
    private Map<String, Long[]> versions = new HashMap<String, Long[]>();
    private Collection<OsmPrimitive> processed;
    private Map<OsmPrimitive,Long> newIdMap;

    /**
     * List of protocol versions that will be accepted on reading
     */

    private class Parser extends DefaultHandler {

        @Override public void startElement(String namespaceURI, String localName, String qName, Attributes atts) throws SAXException {
            try {
                if (qName.equals("osm")) {
                } else if (qName.equals("node") || qName.equals("way") || qName.equals("relation")) {
                    String key = qName + ":" + atts.getValue("old_id");
                    String newid = atts.getValue("new_id");
                    String newver = atts.getValue("new_version");
                    Long[] value = new Long[] { newid == null ? null : new Long(newid), newver == null ? null : new Long(newver) };
                    versions.put(key, value);
                }
            } catch (NumberFormatException x) {
                x.printStackTrace(); // SAXException does not chain correctly
                throw new SAXException(x.getMessage(), x);
            } catch (NullPointerException x) {
                x.printStackTrace(); // SAXException does not chain correctly
                throw new SAXException(tr("NullPointerException, possibly some missing tags."), x);
            }
        }
    }

    /**
     * Parse the given input source and return the dataset.
     */
    public static void parseDiffResult(String source, Collection<OsmPrimitive> osm, Collection<OsmPrimitive> processed, Map<OsmPrimitive,Long> newIdMap, PleaseWaitDialog pleaseWaitDlg)
    throws SAXException, IOException {

       DiffResultReader drr = new DiffResultReader();
       drr.processed = processed;
       drr.newIdMap = newIdMap;
       InputSource inputSource = new InputSource(new StringReader(source));
       try {
           SAXParserFactory.newInstance().newSAXParser().parse(inputSource, drr.new Parser());
       } catch (ParserConfigurationException e1) {
           e1.printStackTrace(); // broken SAXException chaining
           throw new SAXException(e1);
       }

       if (pleaseWaitDlg != null) {
           pleaseWaitDlg.progress.setValue(0);
           pleaseWaitDlg.currentAction.setText(tr("Preparing data..."));
       }

       for (OsmPrimitive p : osm) {
           //System.out.println("old: "+ p);
           p.visit(drr);
           //System.out.println("new: "+ p);
           //System.out.println("");
       }
    }

    public void visit(Node n) {
        String key = "node:" + (newIdMap.containsKey(n) ? newIdMap.get(n) : n.id);
        System.out.println("key: "+key);
        Long[] nv = versions.get(key);
        if (nv != null) {
            processed.add(n);
            if (!n.deleted) {
                n.id = nv[0]; n.version = nv[1].intValue();
            }
        }
    }
    public void visit(Way w) {
        String key = "way:" + (newIdMap.containsKey(w) ? newIdMap.get(w) : w.id);
        Long[] nv = versions.get(key);
        if (nv != null) {
            processed.add(w);
            if (!w.deleted) {
                w.id = nv[0]; w.version = nv[1].intValue();
            }
        }
    }
    public void visit(Relation r) {
        String key = "relation:" + (newIdMap.containsKey(r) ? newIdMap.get(r) : r.id);
        Long[] nv = versions.get(key);
        if (nv != null) {
            processed.add(r);
            if (!r.deleted) {
                r.id = nv[0]; r.version = nv[1].intValue();
            }
        }
    }
}