/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2017 Red Hat, Inc., and individual contributors
 * as indicated by the @author tags.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.wildfly.common.codec;

/**
 * A base-n encoder/decoder alphabet.  Alphabets may be little-endian or big-endian.  Each base has its own subclass.
 */
public abstract class Alphabet {
    private final boolean littleEndian;

    Alphabet(final boolean littleEndian) {
        this.littleEndian = littleEndian;
    }

    /**
     * Determine whether this is a little-endian or big-endian alphabet.
     *
     * @return {@code true} if the alphabet is little-endian, {@code false} if it is big-endian
     */
    public boolean isLittleEndian() {
        return littleEndian;
    }

    /**
     * Encode the given byte value to a code point.
     *
     * @param val the value
     * @return the Unicode code point
     */
    public abstract int encode(int val);

    /**
     * Decode the given code point (character).  If the code point is not valid, -1 is returned.
     *
     * @param codePoint the Unicode code point
     * @return the decoded value or -1 if the code point is not valid
     */
    public abstract int decode(int codePoint);
}
