src/main/java/de/ids_mannheim/korap/response/Match.java

package de.ids_mannheim.korap.response;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.*;

import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.TermContext;
import org.apache.lucene.search.spans.Spans;
import org.apache.lucene.search.spans.SpanTermQuery;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.FixedBitSet;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.annotation.JsonIgnore;
import com.fasterxml.jackson.annotation.JsonInclude;
import com.fasterxml.jackson.annotation.JsonInclude.Include;
import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ArrayNode;
import com.fasterxml.jackson.databind.node.ObjectNode;

import static de.ids_mannheim.korap.util.KrillByte.*;
import de.ids_mannheim.korap.index.AbstractDocument;
import de.ids_mannheim.korap.index.PositionsToOffset;
import de.ids_mannheim.korap.query.SpanElementQuery;
import de.ids_mannheim.korap.response.match.HighlightCombinator;
import de.ids_mannheim.korap.response.match.HighlightCombinatorElement;
import de.ids_mannheim.korap.response.match.MatchIdentifier;
import de.ids_mannheim.korap.response.match.PosIdentifier;
import de.ids_mannheim.korap.response.match.Relation;

/*
 * The snippet building algorithm is quite complicated for now
 * and should probably be refactored.
 * It works like this:
 *
 * 1. For all spans and highlights, pagebreaks etc. all necessary
 *    positions are collected (processHighlight)
 * 2. For all collected positions the character offsets are retrieved
 *    and based on that for all spans and highlights a list
 *    is created with arrays of the spans with the structure
 *    [startchar, endchar, highlightClass] (processHighlightSpans)
 *    2.1 The primary data and optional context information is retrieved
 *        (processOffsetChars)
 * 3. Based on the collected spans 2 lists are created for opening and
 *    closing tags (pretty much clones of the initial span list),
 *    sorted for opening resp. closing, and processed in parallel
 *    to form an open/close stack. The new structure on the stack is
 *    [startchar, endchar, highlightclass, close=0/open=1/empty=2]
 *    (processHighlightStack)
 *    3.1. If the element is a relation with an identifier, this may
 *         be removed if duplicate (filterMultipleIdentifiers)
 * 4. Based on the stack and the primary data the snippet is created.
 *    (processHighlightSnippet)
 *    4.1. To avoid unbalanced elements, all open/close/empty tags
 *         are balanced (i.e. closed and reopened if overlaps occur).
 *         (Highlightcombinator)
 */

/*
 * Todo: The implemented classes and private names are horrible!
 * Refactor, future-me!
 *
 * The number based Highlighttype is ugly - UGLY!
 *
 * substrings may be out of range - e.g. if snippets are not lifted!
 */

/**
 * Representation of Matches in a Result.
 * <strong>Warning:</strong> This is currently highly dependent
 * on DeReKo data and will change in the future.
 * 
 * @author Nils Diewald
 * @see Result
 */
@JsonInclude(Include.NON_NULL)
public class Match extends AbstractDocument {

    // Logger
    private final static Logger log = LoggerFactory.getLogger(Match.class);

	private static final int MAX_MATCH_TOKENS = 50;
	
	// end marker of highlights that are pagebreaks
	private static final int PB_MARKER = -99999;

	// Textual elements that are in context
	private static final int CONTEXT = -99998;

    // This advices the java compiler to ignore all loggings
    public static final boolean DEBUG = false;

    // Mapper for JSON serialization
    ObjectMapper mapper = new ObjectMapper();

    // Snippet information
    @JsonIgnore
    public SearchContext context;

    // Public, while used wildly in tests!
    @JsonIgnore
    public int startPos, endPos = -1;

    @JsonIgnore
    private int innerMatchStartPos, innerMatchEndPos = -1;

    @JsonIgnore
    public int potentialStartPosChar = -1, potentialEndPosChar = -1;

	@JsonIgnore
	public boolean cutted = false;

    private String version;

    // TEMPORARILY
    @JsonIgnore
    public int localDocID = -1;

    private HashMap<Integer, String> annotationNumber = new HashMap<>(16);
    private HashMap<Integer, Relation> relationNumber = new HashMap<>(16);
    private HashMap<Integer, String> identifierNumber = new HashMap<>(16);

    // -1 is match highlight
    int annotationNumberCounter = 256;
    int relationNumberCounter = 2048;
    int identifierNumberCounter = -2;

	private int startPage = -1;
	private int endPage = -1;
	
    private String tempSnippet,
		snippetHTML,
		snippetBrackets,
		identifier,
		mirrorIdentifier;

    private HighlightCombinator snippetArray;

    public boolean startMore = true, endMore = true;

    private Collection<byte[]> payload;
    private ArrayList<Highlight> highlight;
    private LinkedList<int[]> span;

    private PositionsToOffset positionsToOffset;
    private boolean processed = false;


    /**
     * Constructs a new Match object.
     * Todo: Maybe that's not necessary!
     * 
     * @param pto
     *            The PositionsToOffset object, containing relevant
     *            positional information for highlighting
     * @param localDocID
     *            Document ID based on the atomic reader.
     * @param startPos
     *            Start position of the match in the document.
     * @param endPos
     *            End position of the match in the document.
     * 
     * @see #snippetHTML()
     * @see #snippetBrackets()
     * @see PositionsToOffset
     */
    public Match (PositionsToOffset pto, int localDocID, int startPos,
                  int endPos) {
        this.positionsToOffset = pto;
        this.localDocID = localDocID;
        this.setStartPos(startPos);
        this.setEndPos(endPos);
    };


    /**
     * Constructs a new Match object.
     */
    public Match () {};


    /**
     * Constructs a new Match object.
     * 
     * @param idString
     *            Match identifier string as provided by Result.
     * @param includeHighlights
     *            Boolean value indicating if possible provided
     *            highlight information should be ignored or not.
     */
    public Match (String idString, boolean includeHighlights) {
        MatchIdentifier id = new MatchIdentifier(idString);

        if (id.getStartPos() > -1) {
			this.mirrorIdentifier = id.toString();

            if (id.getTextSigle() != null)
                this.setTextSigle(id.getTextSigle());

            // <legacy>
            this.setCorpusID(id.getCorpusID());
            this.setDocID(id.getDocID());
            // </legacy>

            this.setStartPos(id.getStartPos());
            this.setEndPos(id.getEndPos());

            if (includeHighlights)
                for (int[] pos : id.getPos()) {
                    if (pos[0] < id.getStartPos() || pos[1] > id.getEndPos())
                        continue;
                    this.addHighlight(pos[0], pos[1], pos[2]);
				};
        };
    };


    /**
     * Private class of highlights.
	 * TODO: This should probably be renamed, as it not only contains highlights
	 * but also annotations, pagebreaks and relations
     */
    private class Highlight {
        public int start, end;
        public int number = -1;

        // Relational highlight
        public Highlight (int start, int end, String annotation, int refStart, int refEnd) {
            this.start = start;
            this.end = end;
            // TODO: This can overflow!
            this.number = relationNumberCounter++;

			if (DEBUG) {
				log.trace("Add relation (2) '{}': source={}-{} >> target={}-{}",
						  annotation, start, end, refStart, refEnd);
			};
			
            relationNumber.put(this.number, new Relation(annotation, refStart, refEnd));
        };


        // Span highlight
        public Highlight (int start, int end, String annotation) {
            this.start = start;
            this.end = end;

            // TODO: This can overflow!
            if (annotationNumberCounter < 2048) {
                this.number = annotationNumberCounter++;
                annotationNumber.put(this.number, annotation);
            };
        };


        // Simple highlight
        public Highlight (int start, int end, int number) {
            this.start = start;
            this.end = end;
            this.number = number;
        };

		// Pagebreak
		public Highlight (int start, int pagenumber) {
			this.start = start;
			this.end = PB_MARKER;
			this.number = pagenumber;
		};
    };


    // TODO: Here are offsets and highlight offsets!
    // <> payloads have 12 bytes (iii) or 8!?
    // highlightoffsets have 11 bytes (iis)!
    public void addPayload (List<byte[]> payload) {

        if (DEBUG)
            log.trace("Add payloads to match");

        // Reverse to make embedding of highlights correct
        Collections.reverse(payload);
        try {

            ByteBuffer bb = ByteBuffer.allocate(24);

            // TODO: REVERSE ITERATOR!
            for (byte[] b : payload) {

                if (DEBUG)
                    log.trace("Found a payload of pti {}", b[0]);

                // Todo element searches!

                // Highlights! This is a class PTI
                if (b[0] == 0) {
                    bb.put(b);
                    bb.position(1); // Ignore PTI
                    int start = bb.getInt();
                    int end = bb.getInt();
                    byte number = bb.get();

                    if (DEBUG)
                        log.trace(
                                "Have a highlight of class {} in {}-{} inside of {}-{}",
                                unsignedByte(number), start, end,
                                this.getStartPos(), this.getEndPos());

                    // Ignore classes out of match range and set by the system
                    // TODO: This may be decidable by PTI!
                    if (unsignedByte(number) <= 128
                            && start >= this.getStartPos()
                            && end <= this.getEndPos()) {

                        if (DEBUG) {
                            log.trace("Add highlight with class/relationnr {}!",
                                    unsignedByte(number));
                        };

                        this.addHighlight(start, end - 1, number);
                    }
                    else if (DEBUG) {
                        log.trace("Don't add highlight of class {}!",
                                unsignedByte(number));
                    };
                }

                // Element payload for match!
                // This MAY BE the correct match
                else if (b[0] == (byte) 64) {

                    bb.put(b);
                    bb.position(1); // Ignore pti

                    // Wasn't set before
                    if (this.potentialStartPosChar == -1) {
                        this.potentialStartPosChar = bb.getInt(1);
                    }
                    else {
                        if (bb.getInt(0) < this.potentialStartPosChar)
                            this.potentialStartPosChar = bb.getInt(1);
                    };

                    if (bb.getInt(4) > this.potentialEndPosChar && !this.cutted)
                        this.potentialEndPosChar = bb.getInt(5);

                    if (DEBUG)
                        log.trace("Element payload from {} to {}",
                                this.potentialStartPosChar,
                                this.potentialEndPosChar);
                };

                // Clear bytebuffer
                bb.clear();
            };
        }

        catch (Exception e) {
            log.error(e.getMessage());
        }
    };


    /**
     * Insert a highlight for the snippet view by means of positional
     * offsets and an optional class number.
     * 
     * @param start
     *            Integer value of a span's positional start offset.
     * @param end
     *            Integer value of a span's positional end offset.
     * @param number
     *            Optional class number of the highlight.
     */
    public void addHighlight (int start, int end) {
        this.addHighlight(new Highlight(start, end, (int) 0));
    };


    public void addHighlight (int start, int end, byte number) {
        this.addHighlight(new Highlight(start, end, (int) number));
    };


    public void addHighlight (int start, int end, short number) {
        this.addHighlight(new Highlight(start, end, (int) number));
    };


    public void addHighlight (int start, int end, int number) {
        this.addHighlight(new Highlight(start, end, number));
    };


    /**
     * Insert a highlight for the snippet view.
     * 
     * @param hl
     *            A highlight object to add to the match.
     */
    public void addHighlight (Highlight hl) {

        if (this.highlight == null)
            this.highlight = new ArrayList<Highlight>(16);

        if (DEBUG)
            log.trace("Add highlight from pos {}-{} of class {}", hl.start,
                    hl.end, hl.number);

        // Reset the fetched match data
        this._reset();

        this.highlight.add(hl);
    };


    /**
     * Insert a textual annotation for the snippet view by
     * means of positional offsets and an annotation string.
     * 
     * @param start
     *            Integer value of a span's positional start offset.
     * @param end
     *            Integer value of a span's positional end offset.
     * @param annotation
     *            Annotation string.
     */
    public void addAnnotation (int start, int end, String annotation) {

		if (DEBUG && start > end)
			log.warn("Annotation span is negative: {}, {} for {}", start, end, annotation);

        this.addHighlight(new Highlight(start, end, annotation));
    };


    /**
     * Insert an annotated relation for the snippet view by
     * means of relational participant positions and an annotation
     * string.
     * 
     * @param src
     *            Integer value of a span's positional source object.
     * @param target
     *            Integer value of a span's positional target object.
     * @param annotation
     *            Annotation string.
     */
    public void addRelation (int srcStart,
							 int srcEnd,
							 int targetStart,
							 int targetEnd,
							 String annotation) {

		if (DEBUG)
			log.trace("Add relation (1) '{}': source={}-{} >> target={}-{}",
					  annotation, srcStart, srcEnd, targetStart, targetEnd);

		// Add source token
		if (srcEnd == -1) { // || srcStart == srcEnd) {
			this.addHighlight(
				new Highlight(srcStart, srcStart, annotation, targetStart, targetEnd)
				);
		}
		// Add source span
		else {
			this.addHighlight(
				new Highlight(srcStart, srcEnd, annotation, targetStart, targetEnd)
				);
		};

        int id = identifierNumberCounter--;

		// Here is probably the problem: the identifier-number
		// needs to incorporate targetEnd as well

		// Add target token
		// (The last part was previously commented
		// out for unknown reason)
		if (targetEnd == -1 || targetStart == targetEnd) {
			this.addHighlight(new Highlight(targetStart, targetStart, id));

			identifierNumber.put(id, String.valueOf(targetStart));
		}

		// Add target span
		else {
			this.addHighlight(new Highlight(targetStart, targetEnd, id));
			identifierNumber.put(id, targetStart + "-" + targetEnd);

		};
    };


	public void addPagebreak (int start, int pagenumber) {
		this.addHighlight(new Highlight(start, pagenumber));
	};

    /**
     * Get document id.
     */
    @JsonProperty("docID")
    public String getDocID () {
        return super.getID();
    };


	/**
	 * Get start page.
	 */
    @JsonIgnore
	public int getStartPage () {
		return this.startPage;
	};

	
	/**
	 * Get end page.
	 */
    @JsonIgnore
	public int getEndPage () {
		return this.endPage;
	};

	
    /**
     * Set document id.
     * 
     * @param id
     *            String representation of document ID.
     */
    public void setDocID (String id) {
        super.setID(id);
    };


    /**
     * Get the positional start offset of the match.
     */
    @JsonIgnore
    public int getStartPos () {
        return this.startPos;
    };


    /**
     * Get the positional start offset of the class.
     * 
     * @param number
     *            Class number of the highlight.
     */
    @JsonIgnore
    public int getStartPos (int number) {
        if (number > 256 || this.highlight == null)
            return -1;

        // Iterate over highlights to find matching class
        for (Highlight h : this.highlight) {
            if (h.number == number && h.end != PB_MARKER)
                return h.start;
        };

        return -1;
    };


    /**
     * Set the positional start offset of the match.
     * 
     * @param pos
     *            The positional offset.
     */
    @JsonIgnore
    public void setStartPos (int pos) {
        this.startPos = pos;
		if (this.endPos != -1 && (this.endPos - pos) > MAX_MATCH_TOKENS) {
			this.endPos = pos + MAX_MATCH_TOKENS;
			this.cutted = true;
		};
    };


    /**
     * Get the positional end offset of the match.
     */
    @JsonIgnore
    public int getEndPos () {
        return this.endPos;
    };


    /**
     * Get the positional end offset of the class.
     * 
     * @param number
     *            Class number of the highlight.
     */
    @JsonIgnore
    public int getEndPos (int number) {
        if (number > 256 || this.highlight == null)
            return -1;

        // Iterate over highlights to find matching class
        for (Highlight h : this.highlight) {

            // Get the number (incremented by 1)
            if (h.number == number && h.end != PB_MARKER)
                return h.end + 1;
        };

        return -1;
    };


    /**
     * Set the positional end offset of the match.
     * 
     * @param pos
     *            The positional offset.
     */
    @JsonIgnore
    public void setEndPos (int pos) {
		if (this.startPos != -1 && (pos - this.startPos) > MAX_MATCH_TOKENS) {
			pos = this.startPos + MAX_MATCH_TOKENS;
			this.cutted = true;
		};
        this.endPos = pos;
    };


    /**
     * Get the local (i.e. Lucene given) ID of the document.
     */
    @JsonIgnore
    public int getLocalDocID () {
        return this.localDocID;
    };


    /**
     * Set the local (i.e. Lucene given) ID of the document.
     * 
     * @param id
     *            The id of the document.
     */
    @JsonIgnore
    public void setLocalDocID (int id) {
        this.localDocID = id;
    };


    /**
     * Get the PositionsToOffset object.
     * 
     * @see PositionsToOffset
     */
    @JsonIgnore
    public PositionsToOffset getPositionsToOffset () {
        return this.positionsToOffset;
    };


    /**
     * Set the PositionsToOffset object.
     * 
     * @param pto
     *            The PositionsToOffset object
     * @see PositionsToOffset
     */
    @JsonIgnore
    public void setPositionsToOffset (PositionsToOffset pto) {
        this.positionsToOffset = pto;
    };


    /**
     * Get match ID (for later retrieval).
     * 
     * @see MatchIdentifier
     */
    @Override
    @JsonProperty("matchID")
    public String getID () {
		
		// Return identifier as given
        if (this.mirrorIdentifier != null) {
            return this.mirrorIdentifier;
		};

        // Identifier already created
        if (this.identifier != null) {
            return this.identifier;
		};

        // No, nada, nix
        if (this.localDocID == -1)
            return null;


        MatchIdentifier id = this.getMatchIdentifier();

        // Get prefix string corpus/doc
        if (this.getTextSigle() != null) {
            id.setTextSigle(this.getTextSigle());
        }
        // LEGACY
        else {
            id.setCorpusID(this.getCorpusID());
            id.setDocID(this.getDocID());
        };

        return (this.identifier = id.toString());
    };


    @JsonIgnore
    public MatchIdentifier getMatchIdentifier () {
        MatchIdentifier id = new MatchIdentifier();

        id.setStartPos(startPos);
        id.setEndPos(endPos);

        // There are highlights to integrate
        if (this.highlight != null) {
            for (Highlight h : this.highlight) {
                if (h.number >= 256 || h.end == PB_MARKER)
                    continue;

                // Add highlight to the snippet
                id.addPos(h.start, h.end, h.number);
            };
        };

        return id;
    };

    /**
     * Get identifier for a specific position.
     * 
     * @param int
     *            Position to get identifier on.
     */
	@JsonIgnore
    public String getPosID (int pos) {
		return this.getPosID(pos, -1);
	};


	/**
     * Get identifier for a specific position.
     * 
     * @param String
     *            Start and optional end position to get
	 *            identifier on, separated by a dash.
     */
	@JsonIgnore
    public String getPosID (String pos) {

		String[] startEnd = pos.split("-");
		if (startEnd.length == 2) {
			return this.getPosID(
				Integer.parseInt(startEnd[0]),
				Integer.parseInt(startEnd[1])
				);
		}
		return this.getPosID(Integer.parseInt(startEnd[0]), -1);
	};

	

    /**
     * Get identifier for a specific position.
     * 
     * @param int
     *            Start position to get identifier on.
     * @param int
     *            End position to get identifier on.
     */
    @JsonIgnore
	public String getPosID (int start, int end) {

		if (DEBUG)
			log.trace("Retrieve identifier for position {}-{}", start, end);

        // Identifier already given
        if (this.identifier != null)
            return this.identifier;

        // Nothing here
        if (this.localDocID == -1)
            return null;

        PosIdentifier id = new PosIdentifier();

        // Get prefix string corpus/doc
		// <legacy>
        id.setCorpusID(this.getCorpusID());
        id.setDocID(this.getDocID());
		// </legacy>
        id.setTextSigle(this.getTextSigle());
        id.setStart(start);
        id.setEnd(end);

		if (DEBUG)
			log.trace(
				"Identifier is {} in {} ({}-{}) {}",
				id.toString(),
				this.getTextSigle(),
				this.getCorpusID(),
				this.getDocID(),
				start
				);

        return id.toString();
    };


    public Match setContext (SearchContext context) {
        this.context = context;
        return this;
    };


    @JsonIgnore
    public SearchContext getContext () {
        if (this.context == null)
            this.context = new SearchContext();
        return this.context;
    };


	
	// Retrieve pagebreaks in a certain area
	public List<int[]> retrievePagebreaks (String pb) {
		if (this.positionsToOffset != null) {
			return this.retrievePagebreaks(
				this.positionsToOffset.getLeafReader(),
				(Bits) null,
				"tokens",
				pb
				);
		};

		return null;
	};

	// Retrieve pagebreaks in a certain area
    // THIS IS NOT VERY CLEVER - MAKE IT MORE CLEVER!
    public List<int[]> retrievePagebreaks (LeafReaderContext atomic,
										   Bits bitset,
										   String field,
										   String pb) {

		// List of relevant pagebreaks
		List<int[]> pagebreaks = new ArrayList<>(24);

		int charOffset = 0, pagenumber = 0, start = 0;

		if (DEBUG)
			log.debug("Retrieve pagebreaks between {}-{}",
					  this.getStartPos(),
					  this.getEndPos());

		try {

            // Store character offsets in ByteBuffer
            ByteBuffer bb = ByteBuffer.allocate(16);

			// Store last relevant pagebreak in byte array
			byte[] b = null;

			SpanTermQuery stq = new SpanTermQuery(new Term(field, pb));

			if (DEBUG)
				log.trace("Check pagebreaks with {}", stq.toString());

			Spans pagebreakSpans = stq.getSpans(
				atomic, bitset, new HashMap<Term, TermContext>()
				);

			// Iterate over all pagebreaks
			while (pagebreakSpans.next() == true) {

				if (DEBUG) {
					log.debug("There is a pagebreak at {}/{}",
							  pagebreakSpans.doc(),
							  pagebreakSpans.start());
				};
				
				// Current pagebreak is not in the correct document
				if (pagebreakSpans.doc() != this.localDocID) {
					pagebreakSpans.skipTo(this.localDocID);

					// No pagebreaks in this document
					if (pagebreakSpans.doc() != this.localDocID)
						break;
				};

				if (DEBUG)
					log.debug("The pagebreak occurs in the document");
				
				// There is a pagebreak found - check,
				// if it is in the correct area
				if (pagebreakSpans.start() <= this.getStartPos()) {

					if (DEBUG)
						log.debug("PB start position is before match at {}",
								  pagebreakSpans.start());
					
					// Only the first payload is relevant
					b = pagebreakSpans.getPayload().iterator().next();
					start = pagebreakSpans.start();
				}

				// This is the first pagebreak!
				else {

					// b is already defined!
					if (b != null) {
						bb.rewind();
						bb.put(b);
						bb.rewind();

						pagenumber = bb.getInt();
						charOffset = bb.getInt();

						if (DEBUG)
							log.debug("Add pagebreak to list: {}-{}", charOffset, pagenumber);
						
						// This is the first pagebreak!
						pagebreaks.add(new int[]{charOffset, pagenumber});
						if (start >= this.getStartPos()) {

							if (DEBUG)
								log.debug("Add pagebreak to rendering: {}-{}",
										  charOffset,
										  pagenumber);
							this.addPagebreak(charOffset, pagenumber);
						};
					}

					// b wasn't used yet
					if (pagebreakSpans.start() <= this.getEndPos()) {

						// Set new pagebreak
						// Only the first payload is relevant
						b = pagebreakSpans.getPayload().iterator().next();
						bb.rewind();
						bb.put(b);
						bb.rewind();
							
						pagenumber = bb.getInt();
						charOffset = bb.getInt();
						
						// This is the first pagebreak!
						pagebreaks.add(new int[]{charOffset, pagenumber});
						this.addPagebreak(charOffset,pagenumber);
					}

					// Pagebreak beyond the current position
					else {
						break;
					};

					// Reset byte
					b = null;
				};
			};
		}
		catch (Exception e) {
			log.warn("Some problems with ByteBuffer: {}", e.getMessage());
		};

		if (pagebreaks.size() > 0) {
			this.startPage = pagebreaks.get(0)[1];
			if (pagebreaks.size() > 1 && pagebreaks.get(pagebreaks.size()-1) != null)
				this.endPage = pagebreaks.get(pagebreaks.size()-1)[1];
		}
		
		return pagebreaks;
	};


    // Expand the context to a span
    public int[] expandContextToSpan (String element) {

        // TODO: THE BITS HAVE TO BE SET!

        if (this.positionsToOffset != null)
            return this.expandContextToSpan(
                    this.positionsToOffset.getLeafReader(), (Bits) null,
                    "tokens", element);
        return new int[] { 0, 0, 0, 0 };
    };

	

    // Expand the context to a span
    // THIS IS NOT VERY CLEVER - MAKE IT MORE CLEVER!
    public int[] expandContextToSpan (LeafReaderContext atomic, Bits bitset,
            String field, String element) {

        try {
            // Store character offsets in ByteBuffer
            ByteBuffer bb = ByteBuffer.allocate(24);

            SpanElementQuery cquery = new SpanElementQuery(field, element);

            Spans contextSpans = cquery.getSpans(atomic, bitset,
                    new HashMap<Term, TermContext>());

            int newStart = -1, newEnd = -1;
            int newStartChar = -1, newEndChar = -1;

            if (DEBUG)
                log.trace(
                        "Extend match to context boundary with {} in docID {}",
                        cquery.toString(), this.localDocID);

            while (true) {

                // Game over
                if (contextSpans.next() != true)
                    break;

                if (contextSpans.doc() != this.localDocID) {
                    contextSpans.skipTo(this.localDocID);
                    if (contextSpans.doc() != this.localDocID)
                        break;
                };

                // There's a <context> found -- I'm curious,
                // if it's closer to the match than everything before
                if (contextSpans.start() <= this.getStartPos()
                        && contextSpans.end() >= this.getStartPos()) {

                    // Set as newStart
                    newStart = contextSpans.start() > newStart
                            ? contextSpans.start() : newStart;

                    if (DEBUG)
                        log.trace("NewStart is at {}", newStart);

                    // Get character offset (start)
                    if (contextSpans.isPayloadAvailable()) {
                        try {
                            bb.rewind();
                            for (byte[] b : contextSpans.getPayload()) {

                                // Not an element span
                                if (b[0] != (byte) 64)
                                    continue;

                                bb.rewind();
                                bb.put(b);
                                bb.position(1);
                                newStartChar = bb.getInt();
                                newEndChar = bb.getInt();
                                break;
                            };
                        }
                        catch (Exception e) {
                            log.warn("Some problems with ByteBuffer: {}",
                                     e.getMessage());
                        };
                    };
                }
                else {
                    // Has to be resettet to avoid multiple readings of the payload
                    newEndChar = 0;
                };

                // There's an s found, that ends after the match
                if (contextSpans.end() >= this.getEndPos()) {
                    newEnd = contextSpans.end();

                    // Get character offset (end)
                    if (newEndChar == 0 && contextSpans.isPayloadAvailable()) {
                        try {
                            bb.rewind();
                            for (byte[] b : contextSpans.getPayload()) {

                                // Not an element span
                                if (b[0] != (byte) 64)
                                    continue;

                                bb.rewind();
                                bb.put(b);
                                bb.position(1);
                                newEndChar = bb.getInt(1);
                                break;
                            };
                        }
                        catch (Exception e) {
                            log.warn(e.getMessage());
                        };
                    };
                    break;
                };
            };

            // We have a new match surrounding
            if (DEBUG)
                log.trace("New match spans from {}-{}/{}-{}", newStart, newEnd,
                        newStartChar, newEndChar);

            return new int[] { newStart, newEnd, newStartChar, newEndChar };
        }
        catch (IOException e) {
            log.error(e.getMessage());
        };

        return new int[] { -1, -1, -1, -1 };
    };


    // Reset all internal data
    private void _reset () {
        this.processed = false;
        this.snippetHTML = null;
        this.snippetBrackets = null;
		this.identifier = null;

        // Delete all spans
        if (this.span != null)
            this.span.clear();
    };


    // Start building highlighted snippets
    private boolean _processHighlight () {

        if (processed)
            return true;

        // Relevant details are missing
        if (this.positionsToOffset == null || this.localDocID == -1) {
            log.warn("You have to define "
                    + "positionsToOffset and localDocID first before");
            return false;
        };

        if (DEBUG)
            log.trace("--- Start highlight processing ...");

        // Get pto object
        PositionsToOffset pto = this.positionsToOffset;
        pto.add(this.localDocID, this.getStartPos());
        pto.add(this.localDocID, this.getEndPos() - 1);

        if (DEBUG)
            log.trace("PTO will retrieve {} & {} (Match boundary)",
                    this.getStartPos(), this.getEndPos());

        // Set inner match
        if (this.innerMatchEndPos != 1)
            this.addHighlight(this.innerMatchStartPos, this.innerMatchEndPos,
                    -1);

        // Add all highlights for character retrieval
        if (this.highlight != null) {
            for (Highlight hl : this.highlight) {
                if (hl.start >= this.getStartPos()
                        && hl.end <= this.getEndPos()) {

					// Highlight is no pagebreak
					if (hl.end != PB_MARKER) {
						pto.add(this.localDocID, hl.start);
						pto.add(this.localDocID, hl.end);

						if (DEBUG)
							log.trace(
                                "PTO will retrieve {} & {} (Highlight boundary)",
                                hl.start, hl.end);
						
					}

					else if (DEBUG) {
						log.trace("Highlight is a pagebreak - do not retrieve PTO");
					};					
                };
            };
        };

        // Get the list of spans for matches and highlighting
        if (this.span == null || this.span.size() == 0) {
            if (!this._processHighlightSpans())
                return false;
        };

        // Create a stack for highlighted elements
        // (opening and closing elements)
        ArrayList<int[]> stack = this._processHighlightStack();

        if (DEBUG)
            log.trace("The snippet is {}", this.tempSnippet);

        // The temporary snippet is empty, nothing to do
        if (this.tempSnippet == null) {
            processed = true;
            return false;
        };

        // Merge the element stack with the primary textual data
        this._processHighlightSnippet(this.tempSnippet, stack);

        // Match is processed - done
        return (processed = true);
    };


    /*
      Comparator class for opening tags
     */
    private class OpeningTagComparator implements Comparator<int[]> {
        @Override
        public int compare (int[] arg0, int[] arg1) {
            // Check start positions
            if (arg0[0] > arg1[0]) {
                return 1;
            }
            else if (arg0[0] == arg1[0]) {
                // Check endpositions
                if (arg0[1] > arg1[1]) {
                    return -1;
                }
                else if (arg0[1] == arg1[1]) {

                    // Compare class number
                    if (arg0[2] > arg1[2])
                        return 1;
                    else if (arg0[2] < arg1[2])
                        return -1;
                    return 0;

                }
                return 1;
            };
            return -1;
        };
    };

    /*
     * Comparator class for closing tags
     */
    private class ClosingTagComparator implements Comparator<int[]> {
        @Override
        public int compare (int[] arg0, int[] arg1) {
            // Check end positions
            if (arg0[1] > arg1[1]) {
                return 1;
            }
            else if (arg0[1] == arg1[1]) {

                // Check start positions
                if (arg0[0] < arg1[0]) {
                    return 1;
                }
                else if (arg0[0] == arg1[0]) {
                    return 0;
                };
                return -1;
            };
            return -1;
        };
    };


    /*
     * This takes a clean string and the tag stack
     * to decorate the string with annotations.
     */
    private void _processHighlightSnippet (String clean,
            ArrayList<int[]> stack) {

        if (DEBUG) {
            log.trace("--- Process Highlight snippet");
            log.trace("--- Snippet: {}", clean);
		};

        int pos = 0, oldPos = 0;

        this.snippetArray = new HighlightCombinator();

        // Iterate over all elements of the stack
        for (int[] element : stack) {

            // The position is the start position for opening and
			// empty elements and the end position for closing elements
            pos = element[3] != 0 ? element[0] : element[1];

			if (DEBUG)
				log.trace("Add tag at position {} (was {})",
						  pos,
						  oldPos);

			
			// The new position is behind the old position
            if (pos > oldPos) {

				// The position is behind the string length,
				// which may end when an element ends beyond
                if (pos > clean.length()) {

					// Reposition to the end
                    pos = clean.length();

					if (DEBUG)
						log.trace("Position exceeds string, now {}",
								  pos);

                };

				// Add partial string
				if (pos > 0 && pos > oldPos) {
					snippetArray.addString(clean.substring(oldPos, pos));
				};

				// Remember the new position
				oldPos = pos;
            };

			// close tag
            if (element[3] == 0) {

				// Add close
                snippetArray.addClose(element[2]);
            }

			// empty tag
			else if (element[3] == 2) {

				// Add Empty (pagebreak)
                snippetArray.addEmpty(element[2]);
			}
			

			// open tag
            else {
                snippetArray.addOpen(element[2]);
            };
        };

        if (clean.length() > pos && pos >= 0) {
            snippetArray.addString(clean.substring(pos));
        };
    };


    @JsonProperty("snippet")
    public String getSnippetHTML () {

        if (!this._processHighlight())
            return null;

        if (this.processed && this.snippetHTML != null)
            return this.snippetHTML;

        if (DEBUG)
            log.trace("Create HTML Snippet");

        StringBuilder sb = new StringBuilder();
		StringBuilder rightContext = new StringBuilder();

		// Remember ids already defined to
		// have joined elements
		HashSet<String> joins = new HashSet<>(100);

        // Snippet stack sizes
        short start = (short) 0;
        short end = this.snippetArray.size();

		// Create context
        sb.append("<span class=\"context-left\">");
        if (this.startMore)
            sb.append("<span class=\"more\"></span>");

		// Set levels for highlights 
		FixedBitSet level = new FixedBitSet(255);
		level.set(0, 255);
		byte[] levelCache = new byte[255];

		HighlightCombinatorElement elem;

		end--;
		if (end > 0) {

			// First element of sorted array
			elem = this.snippetArray.getFirst();

			// First element is textual
			if (elem.type == 0) {
				sb.append(elem.toHTML(this, level, levelCache, joins));
				// Move start position
				start++;
			};
			sb.append("</span>");

			// Last element of sorted array
			elem = this.snippetArray.getLast();

			// Create right context, if there is any
			rightContext.append("<span class=\"context-right\">");

			// Last element is textual
			if (elem != null && elem.type == 0) {
				rightContext.append(
					elem.toHTML(this, level, levelCache, joins)
					);

				// decrement end
				end--;
			};
		};

		if (this.endMore)
            rightContext.append("<span class=\"more\"></span>");

        rightContext.append("</span>");

        // Iterate through all remaining elements
        sb.append("<span class=\"match\">");
        for (short i = start; i <= end; i++) {

			elem = this.snippetArray.get(i);
			// UNTESTED
			if (elem != null) {
				String elemString = elem.toHTML(
					this, level, levelCache, joins
					);
				if (DEBUG) {
					log.trace("Add node {}", elemString);
				};
				sb.append(elemString);
			}
        };
		if (this.cutted) {
			sb.append("<span class=\"cutted\"></span>");
		};
        sb.append("</span>");
        sb.append(rightContext);

        return (this.snippetHTML = sb.toString());
    };


    @JsonIgnore
    public String getSnippetBrackets () {

        if (!this._processHighlight())
            return null;

        if (this.processed && this.snippetBrackets != null)
            return this.snippetBrackets;

        // Snippet stack sizes
        short start = (short) 0;
        short end = this.snippetArray.size();
        end--;

        StringBuilder sb = new StringBuilder();

        if (this.startMore)
            sb.append("... ");

        // First element of sorted array
        HighlightCombinatorElement elem = this.snippetArray.getFirst();
        if (elem.type == 0) {
            sb.append(elem.toBrackets(this));
            start++;
        };

        sb.append("[");

        // Last element of sorted array
        elem = this.snippetArray.getLast();
        StringBuilder rightContext = new StringBuilder();

        // Last element is textual
        if (elem != null && elem.type == 0) {
            rightContext.append(elem.toBrackets(this));
            // decrement end
            end--;
        };

        for (short i = start; i <= end; i++) {
            sb.append(this.snippetArray.get(i).toBrackets(this));
        };

		if (this.cutted) {
			sb.append("<!>");
		};
        sb.append("]");
        sb.append(rightContext);

        if (this.endMore)
            sb.append(" ...");

        return (this.snippetBrackets = sb.toString());
    };


    // This sorts all highlight and match spans to make them nesting correctly,
    // even in case they overlap
    // TODO: Not very fast - improve!
    private ArrayList<int[]> _processHighlightStack () {
        if (DEBUG)
            log.trace("--- Process Highlight stack");

        LinkedList<int[]> openList = new LinkedList<int[]>();
        LinkedList<int[]> closeList = new LinkedList<int[]>();

        // Filter multiple identifiers, that may be introduced and would
        // result in invalid xml
        this._filterMultipleIdentifiers();

        // Add highlight spans to balance lists
        openList.addAll(this.span);
        closeList.addAll(this.span);

        // Sort balance lists
        Collections.sort(openList, new OpeningTagComparator());
        Collections.sort(closeList, new ClosingTagComparator());

        // New stack array
        ArrayList<int[]> stack = new ArrayList<>(openList.size() * 2);

        // Create stack unless both lists are empty
        while (!openList.isEmpty() || !closeList.isEmpty()) {

			// Nothing more to open -- close all
            if (openList.isEmpty()) {

				if (DEBUG)
					log.debug("No more open tags -- close all non pagebreaks");

				if (closeList.peekFirst()[1] != PB_MARKER) {
					stack.add(closeList.removeFirst());
				}
				else if (DEBUG) {
					if (DEBUG)
						log.debug("Close is pagebreak -- ignore (1)");
				};

                continue;
            }

            // Not sure about this, but it can happen
            else if (closeList.isEmpty()) {
                break;
            };

			// Closener is pagebreak
			if (closeList.peekFirst()[1] == PB_MARKER) {

				if (DEBUG)
					log.debug("Close is pagebreak -- ignore (2)");

				// Remove closing pagebreak
				closeList.removeFirst();
			}

			// Opener is pagebreak
			else if (openList.peekFirst()[1] == PB_MARKER) {
				int[] e = openList.removeFirst().clone();

				if (DEBUG)
					log.debug("Open is pagebreak");

				// Mark as empty
                e[1] = e[0]; // Remove pagebreak marker
                e[3] = 2;

				// Add empty pagebreak
				stack.add(e);
			}

			// check if the opener is smaller than the closener
			else if (openList.peekFirst()[0] < closeList.peekFirst()[1]) {

				if (DEBUG)
					log.debug("Open tag starts before close tag ends");

                int[] e = openList.removeFirst().clone();

				// Mark as opener
				e[3] = 1;

				if (DEBUG) {

					//      -1: match
					//    < -1: relation target
					//  -99998: context
					// >= 2048: relation source
					// >=  256: annotation
					
					log.trace(
						"Add open with number {} to stack at {}-{} as {}",
						e[2], e[0], e[1], e[3]
						);
				};

				// Add opener to stack
                stack.add(e);
            }

			else {
				int[] e = closeList.removeFirst();
				
				if (DEBUG) {
					log.debug("Close ends before open");

					log.trace(
						"Add close with number {} to stack at {}-{}",
						e[2], e[0], e[1]
						);
				};

				// Add closener to stack
                stack.add(e);
            };
        };
        return stack;
    };


    /**
     * Sometimes the match start and end positions are inside the
     * matching region, e.g. when the match was expanded.
     * This will override the original matching positions
     * And matrk the real matching.
     */
    public void overrideMatchPosition (int start, int end) {
        if (DEBUG)
            log.trace("--- Override match position");

        this.innerMatchStartPos = start;
        this.innerMatchEndPos = end;
    };


    /**
     * This will retrieve character offsets for all spans.
     */
    private boolean _processHighlightSpans () {

        if (DEBUG)
            log.trace("--- Process Highlight spans");

        // Local document ID
        int ldid = this.localDocID;

        int startPosChar = -1, endPosChar = -1;

        // No positionsToOffset object found
        if (this.positionsToOffset == null)
            return false;

        // Match position
        startPosChar = this.positionsToOffset.start(ldid, this.startPos);

        if (DEBUG)
            log.trace("Unaltered startPosChar is {}", startPosChar);

        // Check potential differing start characters
        // e.g. from element spans
        if (potentialStartPosChar != -1
                && (startPosChar > this.potentialStartPosChar))
            startPosChar = this.potentialStartPosChar;

        endPosChar = this.positionsToOffset.end(ldid, this.endPos - 1);

        if (DEBUG)
            log.trace("Unaltered endPosChar is {}", endPosChar);

        // Potential end characters may come from spans with
        // defined character offsets like sentences including .", ... etc.
        if (endPosChar < potentialEndPosChar)
            endPosChar = potentialEndPosChar;

        if (DEBUG)
            log.trace("Refined: Match offset is pos {}-{} (chars {}-{})",
                    this.startPos, this.endPos, startPosChar, endPosChar);

        this.identifier = null;

        // No spans yet
        if (this.span == null)
            this.span = new LinkedList<int[]>();

        // Process offset char findings
        int[] intArray = this._processOffsetChars(ldid, startPosChar,
                endPosChar);

        // Recalculate startOffsetChar
        int startOffsetChar = startPosChar - intArray[0];

        // Add match span, in case no inner match is defined
        if (this.innerMatchEndPos == -1) {
			if (DEBUG)
				log.debug("Added array to match span with {} (1)", intArray);
            this.span.add(intArray);
		};

		// Add context highlight
		this.span.add(new int[]{intArray[0], intArray[1], CONTEXT, 0});

        // highlights
        // -- I'm not sure about this.
        if (this.highlight != null) {
            if (DEBUG)
                log.trace("There are highlights!");

            for (Highlight highlight : this.highlight) {
				if (DEBUG && highlight.start > highlight.end) {
					log.warn("Start position is before end position {}-{}!",
							 highlight.start,
							 highlight.end);
				};

				
				int start = -1;
                int end = -1;

				// Highlight is a pagebreak
				if (highlight.end != PB_MARKER) {
					start = this.positionsToOffset.start(ldid, highlight.start);
					end = this.positionsToOffset.end(ldid, highlight.end);
				}
				else {

					if (DEBUG)
						log.trace("Highlight is pagebreak -- do not retrieve offset");

					// In pagebreak highlights
					// there is already a character
					start = highlight.start;
					end = highlight.end;
				};

                if (DEBUG)
                    log.trace("PTO has retrieved {}-{} for class {}", start,
							  end, highlight.number);

                start -= startOffsetChar;

				// Keep end equal -1
				if (end != PB_MARKER) {
					end -= startOffsetChar;
				}
				else if (DEBUG) {
					log.debug("Pagebreak keeps end position");
				};

                if (start < 0 || (end < 0 && end != PB_MARKER))
                    continue;

                // Create intArray for highlight
                intArray = new int[] {
					start,
					end,
					highlight.number,
					0 // Dummy value for later use
                };

				if (DEBUG)
					log.debug("Added array to span with {} (2)", intArray);

                this.span.add(intArray);
            };
        };
        return true;
    };


    // Pass the local docid to retrieve character positions for the offset
    private int[] _processOffsetChars (int ldid, int startPosChar,
            int endPosChar) {

        int startOffsetChar = -1, endOffsetChar = -1;
        int startOffset = -1, endOffset = -1;

        // The offset is defined by a span
        if (this.getContext().isSpanDefined()) {

            if (DEBUG)
                log.trace("Try to expand to <{}>",
                        this.context.getSpanContext());

            this.startMore = false;
            this.endMore = false;

            int[] spanContext = this.expandContextToSpan(
                    this.positionsToOffset.getLeafReader(), (Bits) null,
                    "tokens", this.context.getSpanContext());
            startOffset = spanContext[0];
            endOffset = spanContext[1];
            startOffsetChar = spanContext[2];
            endOffsetChar = spanContext[3];
            if (DEBUG)
                log.trace("Got context based on span {}-{}/{}-{}",
                        startOffset, endOffset, startOffsetChar, endOffsetChar);
        };

        // The offset is defined by tokens or characters
        if (endOffset == -1) {

            PositionsToOffset pto = this.positionsToOffset;

            // The left offset is defined by tokens
            if (this.context.left.isToken()) {
                startOffset = this.startPos - this.context.left.getLength();
                if (DEBUG)
                    log.trace("PTO will retrieve {} (Left context)",
                            startOffset);
                pto.add(ldid, startOffset);
            }

            // The left offset is defined by characters
            else {
                startOffsetChar = startPosChar - this.context.left.getLength();
            };

            // The right context is defined by tokens
            if (this.context.right.isToken()) {
                endOffset = this.endPos + this.context.right.getLength() - 1;
                if (DEBUG)
                    log.trace("PTO will retrieve {} (Right context)",
                            endOffset);
                pto.add(ldid, endOffset);

            }

            // The right context is defined by characters
            else {
                endOffsetChar = (endPosChar == -1) ? -1
                        : endPosChar + this.context.right.getLength();
            };

            if (startOffset != -1)
                startOffsetChar = pto.start(ldid, startOffset);

            if (endOffset != -1)
                endOffsetChar = pto.end(ldid, endOffset);
        };

        if (DEBUG)
            log.trace("Premature found offsets at {}-{}", startOffsetChar,
                    endOffsetChar);


        // This can happen in case of non-token characters
        // in the match and null offsets
        if (startOffsetChar > startPosChar)
            startOffsetChar = startPosChar;
        else if (startOffsetChar < 0)
            startOffsetChar = 0;

        // No "..." at the beginning
        if (startOffsetChar == 0)
            this.startMore = false;

        if (endOffsetChar != -1 && endOffsetChar < endPosChar)
            endOffsetChar = endPosChar;

        if (DEBUG)
            log.trace("The context spans from chars {}-{}", startOffsetChar,
                    endOffsetChar);

        // Get snippet information from the primary data
        if (endOffsetChar > -1
                && (endOffsetChar < this.getPrimaryDataLength())) {
            this.tempSnippet = this.getPrimaryData(startOffsetChar,
                    endOffsetChar);
        }
        else {
            this.tempSnippet = this.getPrimaryData(startOffsetChar);
            this.endMore = false;
        };

        if (DEBUG)
            log.trace("Snippet: '" + this.tempSnippet + "'");

        if (DEBUG)
            log.trace(
                    "The match entry is {}-{} ({}-{}) with absolute offsetChars {}-{}",
                    startPosChar - startOffsetChar,
                    endPosChar - startOffsetChar, startPosChar, endPosChar,
                    startOffsetChar, endOffsetChar);

        // TODO: Simplify
        return new int[] { startPosChar - startOffsetChar,
                endPosChar - startOffsetChar, -1, 0 };
    };


    // Identical to Result!
    public JsonNode toJsonNode () {
        // ObjectNode json = (ObjectNode) mapper.valueToTree(this);
        ObjectNode json = (ObjectNode) super.toJsonNode();

        if (this.context != null)
            json.put("context", this.getContext().toJsonNode());

        if (this.version != null)
            json.put("version", this.getVersion());

		if (this.startPage != -1) {
			ArrayNode pages = mapper.createArrayNode();
			pages.add(this.startPage);
			if (this.endPage != -1 && this.endPage != this.startPage)
				pages.add(this.endPage);

			json.put("pages", pages);
		};

        return json;
    };


    public String toJsonString () {
        JsonNode json = (JsonNode) this.toJsonNode();

        // Match was no match
        if (json.size() == 0)
            return "{}";
        try {
            return mapper.writeValueAsString(json);
        }
        catch (Exception e) {
            log.warn(e.getLocalizedMessage());
        };

        return "{}";
    };


    // Return match as token list
    // TODO: This will be retrieved in case "tokenList" is
    //       requested in "fields"
    public ObjectNode toTokenList () {
        ObjectNode json = mapper.createObjectNode();

        if (this.getDocID() != null)
            json.put("textSigle", this.getDocID());
        else if (this.getTextSigle() != null)
            json.put("textSigle", this.getTextSigle());

        ArrayNode tokens = json.putArray("tokens");

        // Get pto object
        PositionsToOffset pto = this.positionsToOffset;

        // Add for position retrieval
        for (int i = this.getStartPos(); i < this.getEndPos(); i++) {
            pto.add(this.localDocID, i);
        };

        // Retrieve positions
        for (int i = this.getStartPos(); i < this.getEndPos(); i++) {
            ArrayNode token = tokens.addArray();
            for (int offset : pto.span(this.localDocID, i)) {
                token.add(offset);
            };
        };

        return json;
    };


    // Remove duplicate identifiers
    // Yeah ... I mean ... why not?
    private void _filterMultipleIdentifiers () {
        ArrayList<Integer> removeDuplicate = new ArrayList<>(10);
        HashSet<String> identifiers = new HashSet<>(20);
        for (int i = 0; i < this.span.size(); i++) {

            // span is an int array: [Start, End, Number, Dummy]
            int highlightNumber = this.span.get(i)[2];

            // Number is an identifier
            if (highlightNumber < -1) {

                // Get the real identifier
                String idNumber =
					identifierNumber.get(highlightNumber);
                if (identifiers.contains(idNumber)) {
                    removeDuplicate.add(i);
                }
                else {
                    identifiers.add(idNumber);
                };
            };
        };

        // Order the duplicates to filter from the tail
        Collections.sort(removeDuplicate);
        Collections.reverse(removeDuplicate);

        // Delete all duplicate identifiers
        for (int delete : removeDuplicate) {
            this.span.remove(delete);
        };
    };


    /*
     * Get identifier based on class number
     */
    @JsonIgnore
    public String getClassID (int nr) {
        return this.identifierNumber.get(nr);
    };


    /*
     * Get annotation based on id
     */
    @JsonIgnore
    public String getAnnotationID (int nr) {
        return this.annotationNumber.get(nr);
    };


    /*
     * Get relation based on id
     */
    @JsonIgnore
    public Relation getRelationID (int nr) {
        return this.relationNumber.get(nr);
    };
};