/*
* Copyright (c) 2016 Metron, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of Metron, Inc. nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL METRON, INC. BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package com.metsci.glimpse.charts.shoreline.ndgc;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.logging.Logger;
import com.metsci.glimpse.charts.shoreline.LandBox;
import com.metsci.glimpse.charts.shoreline.LandSegment;
import com.metsci.glimpse.charts.shoreline.LandSegmentFactory;
import com.metsci.glimpse.charts.shoreline.LandShape;
import com.metsci.glimpse.charts.shoreline.LandShapeCapable;
import com.metsci.glimpse.charts.shoreline.LandVertex;
import com.metsci.glimpse.util.StringUtils;
public class NgdcFile2 implements LandShapeCapable
{
private static final Logger _logger = Logger.getLogger( NgdcFile2.class.getName( ) );
private static final String _headerLinePrefix = "# HEADER: ";
private static final String _northLatKey = "northLat";
private static final String _southLatKey = "southLat";
private static final String _eastLonKey = "eastLon";
private static final String _westLonKey = "westLon";
private static final String _latOffsetKey = "latOffset";
private static final String _lonOffsetKey = "lonOffset";
private static final String _isSwCornerLandKey = "isSwCornerLand";
private final LandShape _shape;
public NgdcFile2( InputStream in ) throws IOException
{
List<String> fileContent = readFile( in );
List<List<LandVertex>> segments = readSegments( fileContent );
LandBox newLandBox = newLandBox( fileContent, segments );
if ( segments == null || newLandBox == null )
{
_shape = null;
return;
}
List<List<LandVertex>> segments2 = new ArrayList<List<LandVertex>>( segments.size( ) );
for ( List<LandVertex> segment : segments )
if ( !segment.isEmpty( ) ) segments2.add( new ArrayList<LandVertex>( segment ) );
joinConnectedSegments( segments2, true );
List<LandSegment> segments3 = Collections.unmodifiableList( toLandSegments( segments2, newLandBox ) );
_shape = new LandShape( segments3, newLandBox );
}
private static List<String> readFile( InputStream in ) throws IOException
{
List<String> fileContent = new ArrayList<String>( );
String line = null;
BufferedReader reader = new BufferedReader( new InputStreamReader( in ) );
while ( ( line = reader.readLine( ) ) != null )
{
fileContent.add( line );
}
return fileContent;
}
private static List<List<LandVertex>> readSegments( List<String> fileContent )
{
double latOffset = 0.0;
double lonOffset = 0.0;
Map<String, String> headerMap = readHeader( fileContent );
if ( headerMap.containsKey( _latOffsetKey ) ) try
{
latOffset = Double.parseDouble( headerMap.get( _latOffsetKey ) );
}
catch ( NumberFormatException e )
{
}
if ( headerMap.containsKey( _lonOffsetKey ) ) try
{
lonOffset = Double.parseDouble( headerMap.get( _lonOffsetKey ) );
}
catch ( NumberFormatException e )
{
}
long lineNumber = 0;
try
{
List<List<LandVertex>> segments = new ArrayList<List<LandVertex>>( );
List<LandVertex> segment = null;
for ( String line : fileContent )
{
lineNumber++;
if ( line == null ) break;
if ( line.startsWith( _headerLinePrefix ) ) continue;
double lat;
double lon;
if ( line.matches( "^[\\s]*[nN]a[nN][\\s]+[nN]a[nN][\\s]*$|^# -b$" ) )
{
lat = Double.NaN;
lon = Double.NaN;
}
else
{
String[] tokens = StringUtils.split( line.trim( ), '\t' );
if ( tokens.length != 2 ) throw new IOException( String.format( "Line %d: %s", lineNumber, line ) );
lat = Double.parseDouble( tokens[1] ) + latOffset;
lon = Double.parseDouble( tokens[0] ) + lonOffset;
}
if ( Double.isNaN( lat ) || Double.isNaN( lon ) )
{
segment = new ArrayList<LandVertex>( );
segments.add( segment );
}
else
{
segment.add( new LandVertex( lat, lon ) );
}
}
return segments;
}
catch ( Exception e )
{
_logger.warning( "Error reading land file (line " + lineNumber + "): " + e );
return null;
}
}
private static LandBox newLandBox( List<String> fileContent, List<List<LandVertex>> segments )
{
if ( segments == null ) return null;
// First set fallback values in case header values are missing
double northLat = Double.NEGATIVE_INFINITY;
double southLat = Double.POSITIVE_INFINITY;
double eastLon = Double.NEGATIVE_INFINITY;
double westLon = Double.POSITIVE_INFINITY;
for ( List<LandVertex> vertices : segments )
{
for ( LandVertex vertex : vertices )
{
northLat = Math.max( northLat, vertex.lat );
southLat = Math.min( southLat, vertex.lat );
eastLon = Math.max( eastLon, vertex.lon );
westLon = Math.min( westLon, vertex.lon );
}
}
boolean isSwCornerLand = false;
// Now override with header values
Map<String, String> headerMap = readHeader( fileContent );
if ( headerMap.containsKey( _northLatKey ) ) try
{
northLat = Double.parseDouble( headerMap.get( _northLatKey ) );
}
catch ( NumberFormatException e )
{
}
if ( headerMap.containsKey( _southLatKey ) ) try
{
southLat = Double.parseDouble( headerMap.get( _southLatKey ) );
}
catch ( NumberFormatException e )
{
}
if ( headerMap.containsKey( _eastLonKey ) ) try
{
eastLon = Double.parseDouble( headerMap.get( _eastLonKey ) );
}
catch ( NumberFormatException e )
{
}
if ( headerMap.containsKey( _westLonKey ) ) try
{
westLon = Double.parseDouble( headerMap.get( _westLonKey ) );
}
catch ( NumberFormatException e )
{
}
if ( headerMap.containsKey( _isSwCornerLandKey ) ) isSwCornerLand = Boolean.parseBoolean( headerMap.get( _isSwCornerLandKey ) );
return new LandBox( northLat, southLat, eastLon, westLon, isSwCornerLand );
}
private static Map<String, String> readHeader( List<String> fileContent )
{
long lineNumber = 0;
try
{
Map<String, String> headerMap = new HashMap<String, String>( );
for ( String line : fileContent )
{
lineNumber++;
if ( line == null || !line.startsWith( _headerLinePrefix ) ) break;
String[] tokens = StringUtils.split( line.substring( _headerLinePrefix.length( ) ), ' ' );
if ( tokens.length != 2 ) throw new IOException( String.format( "Line %d: %s", lineNumber, line ) );
headerMap.put( tokens[0], tokens[1] );
}
return headerMap;
}
catch ( Exception e )
{
_logger.warning( "Error reading land file (line " + lineNumber + "): " + e );
return null;
}
}
/**
* Reduces segment list to the smallest number of segments by joining connected
* segments. Empty segments are removed.
*
* Iff segment reversal is allowed, segments are joined even if they are connected
* head-to-head or tail-to-tail. In such a case, we first reverse the vertices of
* one of the segments so that they are joined head-to-tail, then append as usual.
*
* Allowing segment reversal sacrifices any hope of use a segment's winding direction
* to infer which side its interior is on, but helps with data in which winding
* direction is meaningless to begin with.
*/
private static void joinConnectedSegments( List<List<LandVertex>> segments, boolean allowSegmentReversal )
{
int joinlessLoopsRemaining = segments.size( );
while ( joinlessLoopsRemaining > 0 )
{
List<LandVertex> base = segments.remove( 0 );
if ( base.isEmpty( ) )
{
joinlessLoopsRemaining--;
continue;
}
boolean anyJoins = false;
for ( Iterator<List<LandVertex>> i = segments.iterator( ); i.hasNext( ); )
{
List<LandVertex> extension = i.next( );
if ( extension.get( 0 ).equals( base.get( base.size( ) - 1 ) ) )
{
base.addAll( extension );
i.remove( );
anyJoins = true;
}
else if ( allowSegmentReversal && extension.get( extension.size( ) - 1 ).equals( base.get( base.size( ) - 1 ) ) )
{
Collections.reverse( extension );
base.addAll( extension );
i.remove( );
anyJoins = true;
}
else if ( allowSegmentReversal && extension.get( 0 ).equals( base.get( 0 ) ) )
{
Collections.reverse( base );
base.addAll( extension );
i.remove( );
anyJoins = true;
}
}
segments.add( base );
joinlessLoopsRemaining = ( anyJoins ? segments.size( ) : joinlessLoopsRemaining - 1 );
}
}
private static List<LandSegment> toLandSegments( List<List<LandVertex>> segments, LandBox box )
{
LandSegmentFactory segmentFactory = new LandSegmentFactory( box );
List<LandSegment> segments2 = new ArrayList<LandSegment>( );
for ( List<LandVertex> vertices : segments )
segments2.add( segmentFactory.newLandSegment( vertices ) );
return segments2;
}
public LandShape toShape( )
{
return _shape;
}
}