// 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.InputStream;

import org.openstreetmap.josm.Main;
import org.openstreetmap.josm.data.osm.DataSet;
import org.openstreetmap.josm.data.gpx.GpxData;
import org.xml.sax.SAXException;


public class BoundingBoxDownloader extends OsmServerReader {

	/**
	 * The boundings of the desired map data.
	 */
	private final double lat1;
	private final double lon1;
	private final double lat2;
	private final double lon2;

	public BoundingBoxDownloader(double lat1, double lon1, double lat2, double lon2) {
		this.lat1 = lat1;
		this.lon1 = lon1;
		this.lat2 = lat2;
		this.lon2 = lon2;
		// store the bounding box in the preferences so it can be
		// re-used across invocations of josm
		Main.pref.put("osm-download.bounds", lat1+";"+lon1+";"+lat2+";"+lon2);
	}

	/**
	 * Retrieve raw gps waypoints from the server API.
	 * @return A list of all primitives retrieved. Currently, the list of lists
	 *      contain only one list, since the server cannot distinguish between
	 *      ways.
	 */
	public GpxData parseRawGps() throws IOException, SAXException {
		Main.pleaseWaitDlg.progress.setValue(0);
		Main.pleaseWaitDlg.currentAction.setText(tr("Contacting OSM Server..."));
		try {
			String url = "trackpoints?bbox="+lon1+","+lat1+","+lon2+","+lat2+"&page=";

			boolean done = false;
			GpxData result = null;
			for (int i = 0;!done;++i) {
				Main.pleaseWaitDlg.currentAction.setText(tr("Downloading points {0} to {1}...", i * 5000, ((i + 1) * 5000)));
				InputStream in = getInputStream(url+i, Main.pleaseWaitDlg);
				if (in == null)
					break;
				GpxData currentGpx = new GpxReader(in, null).data;
				if (result == null) {
					result = currentGpx;
				} else if (currentGpx.hasTrackPoints()) {
					result.mergeFrom(currentGpx);
				} else{
					done = true;
				}
				in.close();
				activeConnection = null;
			}
			result.fromServer = true;
			return result;
		} catch (IllegalArgumentException e) {
			// caused by HttpUrlConnection in case of illegal stuff in the response
			if (cancel)
				return null;
			throw new SAXException("Illegal characters within the HTTP-header response", e);
		} catch (IOException e) {
			if (cancel)
				return null;
			throw e;
		} catch (SAXException e) {
			throw e;
		} catch (Exception e) {
			if (cancel)
				return null;
			if (e instanceof RuntimeException)
				throw (RuntimeException)e;
			throw new RuntimeException(e);
		}
	}

	/**
	 * Read the data from the osm server address.
	 * @return A data set containing all data retrieved from that url
	 */
	public DataSet parseOsm() throws SAXException, IOException {
		try {
			Main.pleaseWaitDlg.progress.setValue(0);
			Main.pleaseWaitDlg.currentAction.setText(tr("Contacting OSM Server..."));
			final InputStream in = getInputStream("map?bbox="+lon1+","+lat1+","+lon2+","+lat2, Main.pleaseWaitDlg);
			if (in == null)
				return null;
			Main.pleaseWaitDlg.currentAction.setText(tr("Downloading OSM data..."));
			final DataSet data = OsmReader.parseDataSet(in, null, Main.pleaseWaitDlg);
			in.close();
			activeConnection = null;
			return data;
		} catch (IOException e) {
			if (cancel)
				return null;
			throw e;
		} catch (SAXException e) {
			throw e;
		} catch (Exception e) {
			if (cancel)
				return null;
			if (e instanceof RuntimeException)
				throw (RuntimeException)e;
			throw new RuntimeException(e);
		}
	}
}