extract nearby station scanning to hafas superclass

git-svn-id: https://public-transport-enabler.googlecode.com/svn/trunk@221 0924bc21-9374-b0fa-ee44-9ff1593b38f0

src/de/schildbach/pte/AbstractHafasProvider.java

@@ -0,0 +1,72 @@
+/*
+ * Copyright 2010 the original author or authors.
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package de.schildbach.pte;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * @author Andreas Schildbach
+ */
+public abstract class AbstractHafasProvider implements NetworkProvider
+{
+	private final static Pattern P_NEARBY_COARSE = Pattern.compile("<tr class=\"(zebra[^\"]*)\">(.*?)</tr>", Pattern.DOTALL);
+	private final static Pattern P_NEARBY_FINE = Pattern.compile(".*?&REQMapRoute0\\.Location0\\.X=(-?\\d+)&REQMapRoute0\\.Location0\\.Y=(-?\\d+)"
+			+ "&.*?[\\?&]input=(\\d+)&[^\"]*\">([^<]*)<.*?", Pattern.DOTALL);
+
+	protected abstract String nearbyStationUri(String stationId);
+
+	public List<Station> nearbyStations(final String stationId, final int lat, final int lon, final int maxDistance, final int maxStations)
+			throws IOException
+	{
+		if (stationId == null)
+			throw new IllegalArgumentException("stationId must be given");
+
+		final List<Station> stations = new ArrayList<Station>();
+
+		final String uri = nearbyStationUri(stationId);
+		final CharSequence page = ParserUtils.scrape(uri);
+
+		final Matcher mCoarse = P_NEARBY_COARSE.matcher(page);
+		while (mCoarse.find())
+		{
+			final Matcher mFine = P_NEARBY_FINE.matcher(mCoarse.group(2));
+			if (mFine.matches())
+			{
+				final int parsedLon = Integer.parseInt(mFine.group(1));
+				final int parsedLat = Integer.parseInt(mFine.group(2));
+				final int parsedId = Integer.parseInt(mFine.group(3));
+				final String parsedName = ParserUtils.resolveEntities(mFine.group(4));
+
+				stations.add(new Station(parsedId, parsedName, parsedLat, parsedLon, 0, null, null));
+			}
+			else
+			{
+				throw new IllegalArgumentException("cannot parse '" + mCoarse.group(2) + "' on " + uri);
+			}
+		}
+
+		if (maxStations == 0 || maxStations >= stations.size())
+			return stations;
+		else
+			return stations.subList(0, maxStations);
+	}
+}