/**
 * This file is part of the Meeds project (https://meeds.io/).
 *
 * Copyright (C) 2020 - 2025 Meeds Association contact@meeds.io
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or (at your option) any later version.
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
package org.exoplatform.web.controller.regexp;

import java.util.NoSuchElementException;


public class Stream {

    /** . */
    private final CharSequence stream;

    /** . */
    private int index;

    public Stream(CharSequence stream) {
        this.stream = stream;
        this.index = 0;
    }

    public int getIndex() {
        return index;
    }

    public void reset() {
        index = 0;
    }

    public boolean hasNext() {
        return hasNext(0);
    }

    public boolean hasNext(int delta) {
        return index + delta < stream.length();
    }

    public boolean hasNext(char c) {
        return hasNext(0, c);
    }

    public boolean hasNext(int delta, char c) {
        int offset = index + delta;
        return offset < stream.length() && stream.charAt(offset) == c;
    }

    public boolean next(char c) {
        boolean a = index < stream.length() && stream.charAt(index) == c;
        if (a) {
            index++;
        }
        return a;
    }

    public Character peek() {
        return peek(0);
    }

    public Character peek(int delta) {
        int offset = index + delta;
        if (offset < stream.length()) {
            return stream.charAt(offset);
        } else {
            return null;
        }
    }

    public char next() {
        if (hasNext()) {
            return stream.charAt(index++);
        } else {
            throw new NoSuchElementException();
        }
    }
}
