/*
 *                    BioJava development code
 *
 * This code may be freely distributed and modified under the
 * terms of the GNU Lesser General Public Licence.  This should
 * be distributed with the code.  If you do not have a copy,
 * see:
 *
 *      http://www.gnu.org/copyleft/lesser.html
 *
 * Copyright for this code is held jointly by the individual
 * authors.  These should be listed in @author doc comments.
 *
 * For more information on the BioJava project and its aims,
 * or to join the biojava-l mailing list, visit the home page
 * at:
 *
 *      http://www.biojava.org/
 *
 */
package org.biojava.nbio.core.search.io.blast;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.LineNumberReader;
import java.text.ParseException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Scanner;
import org.biojava.nbio.core.search.io.Hit;
import org.biojava.nbio.core.search.io.Hsp;
import org.biojava.nbio.core.search.io.Result;
import org.biojava.nbio.core.search.io.ResultFactory;
import org.biojava.nbio.core.sequence.template.Sequence;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.util.Map;

/**
 * Designed by Paolo Pavan.
 * You may want to find my contacts on Github and LinkedIn for code info
 * or discuss major changes.
 * https://github.com/paolopavan
 *
 * @author Paolo Pavan
 */

public class BlastTabularParser implements ResultFactory {
	private final String blastReference =
			"Zheng Zhang, Scott Schwartz, Lukas Wagner, and Webb Miller (2000), A greedy algorithm for aligning DNA sequences&quot;, J Comput Biol 2000; 7(1-2):203-14.";
	/**
	 * Tries to define a different level of consistency during parsing.
	 * LITERAL is intended a strict parsing much tight to the report.
	 * IMPROVED consistency tries to import data much tight to the data model
	 * (I hope you got the idea, if not, have a look to the code.
	 * I suggest to use improved unless you have reasons to do not)
	 */
	private enum PARSING_CONSISTENCY {
		IMPROVED,
		LITERAL
	}
	private static final Logger log = LoggerFactory.getLogger(BlastTabularParser.class);


	private File targetFile;
	private int fileLinesCount;
	private PARSING_CONSISTENCY parsingConsistency = PARSING_CONSISTENCY.IMPROVED;


	// data imported private:
	int queryIdNumber = 0;
	Map<String, String> queryIdMapping = new HashMap<>();
	String programName=null, queryName = null, databaseFile = null;
	private String queryId      ;
	private String subjectId    ;
	private String percIdentity ;
	private String alnLength    ;
	private String mismatchCount;
	private String gapOpenCount ;
	private String queryStart   ;
	private String queryEnd     ;
	private String subjectStart ;
	private String subjectEnd   ;
	private String evalue       ;
	private String bitScore     ;


	@Override
	public List<String> getFileExtensions() {
		List<String> l = new ArrayList<>();
		l.add("blasttabular");
		l.add("blasttxt");
		return l;
	}

	@Override
	public void setFile(File f) {
		targetFile = f;
	}

	@Override
	public List<Result> createObjects(double maxEScore) throws IOException, ParseException {
		List<Result> results = new ArrayList<>();

		log.info("Query for hits");
		LineNumberReader  lnr = new LineNumberReader(new FileReader(targetFile));
		lnr.skip(Long.MAX_VALUE);
		fileLinesCount = lnr.getLineNumber();
		log.info(fileLinesCount + " hits approximately in all results");
		lnr.close();

		FileInputStream fileInputStream = new FileInputStream(targetFile);
		Scanner scanner = new Scanner(fileInputStream);

		String line = fetchData(scanner);
		int lineNumber=0;
		while (lineNumber < fileLinesCount){
			try {
				BlastResultBuilder resultBuilder = new BlastResultBuilder();
				resultBuilder
						.setQueryID(queryId)
						.setDbFile(databaseFile)
						.setProgram(programName)
						.setQueryDef(queryName)
						.setReference(blastReference);

				List<Hit> hits = new ArrayList<>();

				String currentQueryId = queryId;
				while (currentQueryId.equals(queryId) && lineNumber < fileLinesCount){
					BlastHitBuilder hitBuilder = new BlastHitBuilder();

					List<Hsp> hsps = new ArrayList<>();

					String currentSubjectId=subjectId;
					while (currentSubjectId.equals(subjectId) && lineNumber < fileLinesCount){
						if (Double.valueOf(evalue) > maxEScore) {
							line = fetchData(scanner);
							lineNumber++;
							continue;
						}
						BlastHspBuilder hspBuilder = new BlastHspBuilder();
						hspBuilder
							.setHspAlignLen(Integer.valueOf(alnLength))
							.setHspGaps(Integer.valueOf(gapOpenCount))
							.setHspQueryFrom(Integer.valueOf(queryStart))
							.setHspQueryTo(Integer.valueOf(queryEnd))
							.setHspHitFrom(Integer.valueOf(subjectStart))
							.setHspHitTo(Integer.valueOf(subjectEnd))
							.setHspEvalue(Double.valueOf(evalue))
							.setHspBitScore(Double.valueOf(bitScore))
							.setPercentageIdentity(Double.valueOf(percIdentity)/100)
							.setMismatchCount(Integer.valueOf(mismatchCount));
						hsps.add(hspBuilder.createBlastHsp());
						if (scanner.hasNext()) line = fetchData(scanner);
						lineNumber++;
					}
					hits.add(hitBuilder.setHsps(hsps).createBlastHit());
				}
				results.add(resultBuilder.setHits(hits).createBlastResult());
			} catch (NumberFormatException e) {
				throw new ParseException("Invalid numeric value met at line "+ lineNumber+" in:\n"+line,0);
			}
		}
		return results;
	}

	private String fetchData(Scanner scanner){
		String line;
		String[] split;

		line = scanner.nextLine();
		while (line.startsWith("#")){
			// blast tabular with header options contains some more informations
			if (line.matches("#\\s.?BLAST.+")) programName = line.replace("#\\s","");
			if (line.startsWith("# Query:")) queryName = line.replace("# Query: ","");
			if (line.startsWith("# Database:")) databaseFile = line.replace("# Database: ","");

			// needed because blast report can end with a comment...
			if (!scanner.hasNext()) return null;
			line = scanner.nextLine();
		}

		// Here, programName != null checks if there was a header in the file
		boolean headerFound = programName != null;

		split = line.split("\\t");
		queryId      =split[0];
		subjectId    =split[1];
		percIdentity =split[2];
		alnLength    =split[3];
		mismatchCount=split[4];
		gapOpenCount =split[5];
		queryStart   =split[6];
		queryEnd     =split[7];
		subjectStart =split[8];
		subjectEnd   =split[9];
		evalue       =split[10];
		bitScore     =split[11];

		// blast tabular reports only the first word of the query name.
		// If it was specified in the header it is better to use that definition
		if (parsingConsistency == PARSING_CONSISTENCY.IMPROVED && headerFound) {
			if (queryIdMapping.get(queryId)==null) {
				queryIdNumber ++;
				queryIdMapping.put(queryId,"Query_" + queryIdNumber);
			}
			// If a complete definition of the query name was readed, than we can use
			// a queryID schema that is consistent with blast xml report
			queryId = queryIdMapping.get(queryId);
		}
		if (!headerFound) queryName = queryId;

		return line;
	}

	@Override
	public void storeObjects(List<Result> results) throws IOException, ParseException {
		throw new UnsupportedOperationException("Not supported yet.");
	}

	/**
	 * Intended for use with run module.
	 * Although possible, does not make a lot of sense to have it with limited
	 * information such those in tabular report
	 * @param sequences
	 */
	@Override
	public void setQueryReferences(List<Sequence> sequences) {
		throw new UnsupportedOperationException("Not supported for this parser.");
	}
	/**
	 * Intended for use with run module.
	 * Although possible, does not make a lot of sense to have it with limited
	 * information such those in tabular report
	 * @param sequences
	 */
	@Override
	public void setDatabaseReferences(List<Sequence> sequences) {
		throw new UnsupportedOperationException("Not supported for this parser.");
	}
	 /**
	 * Tries to define a different level of consistency during parsing.
	 * LITERAL is intended a strict parsing much tight to the report.
	 * IMPROVED consistency tries to import data much tight to the data model
	 * (I hope you got the idea, if not, have a look to the code.
	 * I suggest to use improved unless you have reasons to do not)
	 */
	public void setParsingConsistency(PARSING_CONSISTENCY parsingConsistency) {
		this.parsingConsistency = parsingConsistency;
	}

}
