--- android/TrainInfoService/src/dk/thoerup/traininfoservice/StationDAO.java	2010/06/11 17:17:06	838
+++ android/TrainInfoService/src/dk/thoerup/traininfoservice/StationDAO.java	2010/06/15 05:33:14	848
@@ -9,6 +9,8 @@
 import java.util.List;
 
 public class StationDAO {
+	final static int LOCATION_LIMIT = 5;
+	
 	private StationBean convertSingleRow(ResultSet res) throws SQLException {
 		StationBean station = new StationBean();
 
@@ -101,21 +103,25 @@
 		return result;
 	}
 
-	//the "hack" with max 1.5 degrees latitude and 2.5 degrees longitude is only valid since we only service danish trains
-	// in denmark 1.5dg latitude ~ 165km, 2.5dg longitude ~ 155km
+	//the "hack" with max 1.0 degrees latitude and 2.0 degrees longitude is only valid since we only service danish trains
+	// in denmark 1.0dg latitude ~ 110km, 2.0dg longitude ~ 120km
 
 	// the ultra fast method  (and only slightly inaccurate as long as we only cover a limited geographically area)
 	// is using an aproximation of the length of 1 latitude degree and 1 longitude degree and just use pythagoras to 
 	// calculate the distance:
 	//     sqrt( power(abs(latitude-?)*111320, 2) + power(abs(longitude-?)*63000,2) )::int as calcdist 
 
-	public List<StationBean> getByLocation(double latitude, double longitude) throws SQLException {
-		String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address," + 
-		"       earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " + 
-		"FROM trainstations " +
-		"WHERE enabled = true AND abs(latitude-?)<1.5 AND abs(longitude-?)<2.5 " +
-		"ORDER BY calcdist ASC " + 
-		"LIMIT 4 ";
+	public List<StationBean> getByLocationWorker(double latitude, double longitude, boolean geolimit) throws SQLException {
+		
+		String limitExpression = geolimit == true ? "AND abs(latitude-?)<1.0 AND abs(longitude-?)<2.0 " : "";
+		
+		String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, " + 
+			"earth_distance( earth_coord, ll_to_earth(?,?))::int AS calcdist " + 
+			"FROM trainstations " +
+			"WHERE enabled = true " + limitExpression +
+			"ORDER BY calcdist ASC " + 
+			"LIMIT " + LOCATION_LIMIT;
+		
 		List<StationBean> result;
 		Connection conn = null;
 		PreparedStatement stmt = null;
@@ -125,8 +131,10 @@
 			stmt = conn.prepareStatement(SQL);
 			stmt.setDouble(1, latitude);
 			stmt.setDouble(2, longitude);
-			stmt.setDouble(3, latitude);
-			stmt.setDouble(4, longitude);			
+			if (geolimit == true) {
+				stmt.setDouble(3, latitude);
+				stmt.setDouble(4, longitude);
+			}
 			res = stmt.executeQuery();
 			result = convertResultset(res);
 
@@ -140,6 +148,18 @@
 		}
 		return result;
 	}
+	
+	public List<StationBean> getByLocation(double latitude, double longitude) throws SQLException {
+		List<StationBean> result = getByLocationWorker(latitude, longitude, true);
+		
+		if (result.size() < LOCATION_LIMIT) { //failover
+			result = getByLocationWorker(latitude, longitude, false);
+		}
+		
+		return result;
+	}
+	
+	
 
 	public List<StationBean> getByList(String list) throws SQLException {
 		String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog,stationcode_metro, address,0.0 " + 
@@ -192,7 +212,7 @@
 		return station;
 	}
 
-	public int getBySpecificName(String name) throws SQLException {
+	public int getIdByName(String name) throws SQLException {
 		String SQL = "SELECT id,name,latitude,longitude,stationcode_fjrn,stationcode_stog, stationcode_metro, address, 0.0 " + 
 		"FROM trainstations " + 
 		"WHERE name = ?  AND enabled = true " +