package org.autoplot.html;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.net.URI;
import java.net.URLDecoder;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.text.html.parser.ParserDelegator;
import org.das2.util.LoggerManager;
import org.das2.util.monitor.NullProgressMonitor;
import org.das2.util.monitor.ProgressMonitor;
import org.das2.qds.DataSetOps;
import org.das2.qds.QDataSet;
import org.autoplot.datasource.AbstractDataSource;
import org.autoplot.datasource.capability.Streaming;

/**
 * Data source for extracting data from HTML tables.  This has been used
 * for looking at real estate sales and weather history.
 * @author jbf
 */
public class HtmlTableDataSource extends AbstractDataSource {

    private static final Logger logger= LoggerManager.getLogger("apdss.html");
    
    /**
     * the parameter name (not label) to plot
     */
    public static final String PARAM_COLUMN= "column";
    public static final String PARAM_TABLE= "table";
    public static final String PARAM_UNITS= "units";
    
    public HtmlTableDataSource(URI uri) {
        super(uri);
        addCapability( Streaming.class, new AsciiTableStreamingSource() );
    }

    /**
     * read the table from the file.
     * @param mon
     * @return
     * @throws IOException 
     */
    public QDataSet getTable( ProgressMonitor mon ) throws IOException  {
        File f= getHtmlFile(resourceURI.toURL(),mon);

        try (BufferedReader reader = new BufferedReader( new FileReader(f))) {

            HtmlParserCallback callback = new HtmlParserCallback(  );

            String units= getParam("units",null);
            if ( units!=null ) {
                callback.setUnits(URLDecoder.decode(units,"UTF-8"));
            }
            
            String stable= (String)getParams().get( PARAM_TABLE );
            if ( stable!=null ) callback.setTable( stable );
            new ParserDelegator().parse( reader, callback, true );

            QDataSet ds= callback.getDataSet();

            return ds;
            
        }
    }

    @Override
    public QDataSet getDataSet( ProgressMonitor mon ) throws IOException {
        QDataSet ds = getTable( mon );
        
        String column=  (String) getParams().get(PARAM_COLUMN);
        if ( column==null ) {
            return ds;
        } else {
            try {
                int icol= Integer.parseInt(column);
                return DataSetOps.unbundle( ds, icol );
            } catch ( NumberFormatException ex ) {
                return DataSetOps.unbundle( ds, column );
            }
        }
        
        }
        
    /**
     * return a list of the tables, with column and human readable description after.
     * @return a list of the tables, with column and human readable description after.
     * @throws java.io.IOException 
     */
    public List<String> getTables() throws java.io.IOException {
        File f= getHtmlFile( resourceURI.toURL(), new NullProgressMonitor() );

        BufferedReader reader = new BufferedReader( new FileReader(f));

        HtmlParserCallback callback = new HtmlParserCallback(  );

        String stable= (String)getParams().get( PARAM_TABLE );
        if ( stable!=null ) callback.setTable( stable );
        new ParserDelegator().parse( reader, callback, true );

        List<String> tables= new ArrayList(callback.getTables());

        return tables;

    }

    private class AsciiTableStreamingSource implements Streaming {

        public AsciiTableStreamingSource() {
        }

        @Override
        public Iterator<QDataSet> streamDataSet(ProgressMonitor mon) throws Exception {
            AsciiTableStreamer result= new AsciiTableStreamer();
            final File f= getHtmlFile( resourceURI.toURL(),mon );

            final BufferedReader reader = new BufferedReader( new FileReader(f) );

            final HtmlParserStreamer callback = new HtmlParserStreamer(  );
            callback.ascii= result;

            String units= getParam("units",null);
            if ( units!=null ) {
                callback.setUnits(URLDecoder.decode(units,"UTF-8"));
            }

            String stable= (String)getParams().get( PARAM_TABLE );
            if ( stable!=null ) callback.setTable( stable );

            Runnable run= new Runnable() {
                @Override
                public void run() {
                    try {
                        new ParserDelegator().parse( reader, callback, true );
                        logger.log(Level.FINE, "Done parsing {0}", f);
                    } catch ( IOException ex ) {

                    } finally {
                        try {
                            reader.close();
                        } catch ( IOException ex ) {
                            logger.log( Level.WARNING, ex.getMessage(), ex );
                        }
                    }
                }
            };

            new Thread( run, "HtmlTableDataStreamer" ).start();
            //new ParserDelegator().parse( reader, callback, true );

            return result;

        }
    }
}