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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * The Universal Permissive License (UPL), Version 1.0
 *
 * Subject to the condition set forth below, permission is hereby granted to any
 * person obtaining a copy of this software, associated documentation and/or
 * data (collectively the "Software"), free of charge and under any and all
 * copyright rights in the Software, and any and all patent rights owned or
 * freely licensable by each licensor hereunder covering either (i) the
 * unmodified Software as contributed to or provided by such licensor, or (ii)
 * the Larger Works (as defined below), to deal in both
 *
 * (a) the Software, and
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 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if
 * one is included with the Software each a "Larger Work" to which the Software
 * is contributed by such licensors),
 *
 * without restriction, including without limitation the rights to copy, create
 * derivative works of, display, perform, and distribute the Software and make,
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 * Software and the Larger Work(s), and to sublicense the foregoing rights on
 * either these or other terms.
 *
 * This license is subject to the following condition:
 *
 * The above copyright notice and either this complete permission notice or at a
 * minimum a reference to the UPL must be included in all copies or substantial
 * portions of the Software.
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 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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package com.oracle.truffle.regex.charset;

import java.util.Iterator;

import com.oracle.truffle.regex.tregex.buffer.IntRangesBuffer;
import com.oracle.truffle.regex.tregex.string.Encodings.Encoding;

public class CodePointSetAccumulator implements Iterable<Range> {

    private IntRangesBuffer acc = new IntRangesBuffer();
    private IntRangesBuffer tmp;

    public CodePointSetAccumulator() {
    }

    public IntRangesBuffer get() {
        return acc;
    }

    public IntRangesBuffer getTmp() {
        if (tmp == null) {
            tmp = new IntRangesBuffer();
        }
        return tmp;
    }

    public void addRange(int lo, int hi) {
        acc.addRange(lo, hi);
    }

    public void addCodePoint(int cp) {
        addRange(cp, cp);
    }

    public void appendRange(Range r) {
        appendRange(r.lo, r.hi);
    }

    public void appendRange(int lo, int hi) {
        acc.appendRange(lo, hi);
    }

    public void addSet(SortedListOfRanges set) {
        IntRangesBuffer t = getTmp();
        tmp = acc;
        acc = t;
        SortedListOfRanges.union(tmp, set, acc);
    }

    public void clear() {
        acc.clear();
    }

    public boolean isEmpty() {
        return acc.isEmpty();
    }

    public boolean matchesSingleChar() {
        return acc.matchesSingleChar();
    }

    public void copyTo(CodePointSetAccumulator other) {
        other.clear();
        acc.appendRangesTo(other.acc, 0, acc.size());
    }

    public CodePointSet toCodePointSet() {
        return CodePointSet.create(acc);
    }

    public void invert(CodePointSetAccumulator target, Encoding encoding) {
        if (acc.isEmpty()) {
            target.addRange(encoding.getMinValue(), encoding.getMaxValue());
            return;
        }
        if (acc.getMin() > encoding.getMinValue()) {
            target.addRange(encoding.getMinValue(), acc.getMin() - 1);
        }
        for (int i = 1; i < acc.size(); i++) {
            target.addRange(acc.getHi(i - 1) + 1, acc.getLo(i) - 1);
        }
        if (acc.getMax() < encoding.getMaxValue()) {
            target.addRange(acc.getMax() + 1, encoding.getMaxValue());
        }
    }

    public void intersectWith(SortedListOfRanges other) {
        IntRangesBuffer t = getTmp();
        tmp = acc;
        acc = t;
        SortedListOfRanges.intersect(tmp, other, acc);
    }

    @Override
    public Iterator<Range> iterator() {
        return acc.rangesIterator();
    }
}