package cytoscape.util;

import java.net.URL;
import java.net.URLConnection;

import cytoscape.data.ImportHandler;
import cytoscape.data.readers.GraphReader;
import cytoscape.data.readers.NNFReader;
import cytoscape.logger.CyLogger;

/**
 * File filter for Nested Network Format (NNF).
 * 
 * @author kono, ruschein
 * @since Cytoscape 2.7.0
 */
public class NNFFileFilter extends CyFileFilter {
	/**
	 * NNF Files are Graphs.
	 */
	private static String fileNature = ImportHandler.GRAPH_NATURE;

	
	/**
	 * File Extension.
	 */
	private static String fileExtension = "nnf";

	
	/**
	 * Content Types
	 */
	private static String[] contentTypes = { "text/nnf" };

	
	/**
	 * Filter Description.
	 */
	private static String description = "NNF files";

	
	/**
	 * Constructor.
	 */
	public NNFFileFilter() {
		super(fileExtension, description, fileNature);
	}

	
	/**
	 * Gets Graph Reader.
	 * 
	 * @param fileName
	 *            File name.
	 * @return GraphReader Object.
	 */
	public GraphReader getReader(String fileName) {
		reader = new NNFReader(fileName);

		return reader;
	}

	/**
	 * Gets Graph Reader.
	 * 
	 * @param fileName
	 *            File name.
	 * @return GraphReader Object.
	 */
	public GraphReader getReader(URL url, URLConnection conn) {
		try {
			// Get the input stream
			reader = new NNFReader(conn.getInputStream(), url.toString());
		} catch (Exception e) {
			CyLogger.getLogger(NNFFileFilter.class).error("Unable to get NNF reader: " + e.getMessage());
			reader = null;
		}
		return reader;
	}
}