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/*
 * The MIT License
 *
 * Copyright 2016 Jong Soft.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.jongsoft.utils.collection;

import com.jongsoft.utils.core.Value;
import com.jongsoft.utils.core.None;
import com.jongsoft.utils.core.Some;

import java.util.function.Consumer;
import java.util.function.Function;

public class TailedList implements List {

    private Value entry;
    private TailedList tail;

    private TailedList(T entry, TailedList tail) {
        this.entry = Some.some(entry);
        this.tail = tail;
    }

    TailedList() {
        this.entry = None.none();
    }

    @Override
    public TailedList push(T entity) {
        return new TailedList<>(entity, this);
    }

    @Override
    public T get(int index) {
        if (!entry.isPresent()) {
            throw new IndexOutOfBoundsException();
        }

        return index == 0
                ? entry.get()
                : tail.get(index - 1);
    }

    @Override
    public  TailedList map(Function mapper) {
        return entry.isPresent()
                ? tail.map(mapper).push(mapper.apply(entry.get()))
                : new TailedList<>();
    }

    @Override
    public void forEach(Consumer consumer) {
        if (entry.isPresent()) {
            tail.forEach(consumer);
            consumer.accept(entry.get());
        }
    }

    @Override
    public int size() {
        return entry.isPresent()
                ? 1 + tail.size()
                : 0;
    }
}