/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you 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 groovy.lang;

import org.codehaus.groovy.runtime.typehandling.DefaultTypeTransformation;

import java.io.Serializable;
import java.util.AbstractList;
import java.util.Arrays;
import java.util.List;
import java.util.Objects;
import java.util.RandomAccess;

/**
 * Represents a list of Objects.
 */
public class Tuple<E> extends AbstractList<E> implements Serializable, Cloneable, Comparable<Tuple<E>>, RandomAccess {
    private static final long serialVersionUID = -6707770506387821031L;
    private final E[] contents;

    @SafeVarargs
    public Tuple(E... contents) {
        if (contents == null) throw new NullPointerException();
        this.contents = contents;
    }

    public Tuple(Tuple<E> tuple) {
        this.contents = tuple.contents;
    }

    @Override
    public E get(int index) {
        return contents[index];
    }

    @Override
    public int size() {
        return contents.length;
    }

    @SuppressWarnings("unchecked")
    @Override
    public E[] toArray() {
        int size = size();
        E[] copy = (E[]) new Object[size];
        System.arraycopy(contents, 0, copy, 0, size);
        return copy;
    }

    @SuppressWarnings("unchecked")
    @Override
    public <T> T[] toArray(T[] a) {
        int size = size();
        if (a.length < size)
            a = (T[]) new Object[size];

        System.arraycopy(contents, 0, a, 0, size);
        Arrays.fill(a, size, a.length, null);
        return a;
    }

    @SuppressWarnings("unchecked")
    @Override
    public List<E> subList(int fromIndex, int toIndex) {
        int size = toIndex - fromIndex;
        E[] newContent = (E[]) new Object[size];
        System.arraycopy(contents, fromIndex, newContent, 0, size);
        return new Tuple<>(newContent);
    }

    public Tuple<E> subTuple(int fromIndex, int toIndex) {
        return (Tuple<E>) subList(fromIndex, toIndex);
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (!(o instanceof Tuple)) return false;

        Tuple that = (Tuple) o;
        int size = size();
        if (size != that.size()) return false;
        for (int i = 0; i < size; i++) {
            if (!DefaultTypeTransformation.compareEqual(get(i), that.get(i))) {
                return false;
            }
        }
        return true;
    }

    @Override
    public int hashCode() {
        return Objects.hash(contents);
    }

    @Override
    public int compareTo(Tuple<E> other) {
        int thisSize = this.size();
        int otherSize = other.size();

        for (int i = 0, n = Math.min(thisSize, otherSize); i < n; i++) {
            int result = compare(this.get(i), other.get(i));
            if (result != 0) {
                return result;
            }
        }

        return Integer.compare(thisSize, otherSize);
    }

    @SuppressWarnings("unchecked")
    private static <T> int compare(T t1, T t2) {
        return t1 == null && t2 == null
                ? 0
                : t1 == null
                ? 1
                : t2 == null
                ? -1
                : t1 instanceof Comparable
                ? ((Comparable<T>) t1).compareTo(t2)
                : DefaultTypeTransformation.compareEqual(t1, t2)
                ? 0
                : 1;
    }

    /**
     * Construct a tuple of degree 0.
     */
    public static Tuple0 tuple() {
        return Tuple0.INSTANCE;
    }

    /**
     * Construct a tuple of degree 1.
     */
    public static <T1> Tuple1<T1> tuple(T1 v1) {
        return new Tuple1<>(v1);
    }

    /**
     * Construct a tuple of degree 2.
     */
    public static <T1, T2> Tuple2<T1, T2> tuple(T1 v1, T2 v2) {
        return new Tuple2<>(v1, v2);
    }

    /**
     * Construct a tuple of degree 3.
     */
    public static <T1, T2, T3> Tuple3<T1, T2, T3> tuple(T1 v1, T2 v2, T3 v3) {
        return new Tuple3<>(v1, v2, v3);
    }

    /**
     * Construct a tuple of degree 4.
     */
    public static <T1, T2, T3, T4> Tuple4<T1, T2, T3, T4> tuple(T1 v1, T2 v2, T3 v3, T4 v4) {
        return new Tuple4<>(v1, v2, v3, v4);
    }

    /**
     * Construct a tuple of degree 5.
     */
    public static <T1, T2, T3, T4, T5> Tuple5<T1, T2, T3, T4, T5> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5) {
        return new Tuple5<>(v1, v2, v3, v4, v5);
    }

    /**
     * Construct a tuple of degree 6.
     */
    public static <T1, T2, T3, T4, T5, T6> Tuple6<T1, T2, T3, T4, T5, T6> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6) {
        return new Tuple6<>(v1, v2, v3, v4, v5, v6);
    }

    /**
     * Construct a tuple of degree 7.
     */
    public static <T1, T2, T3, T4, T5, T6, T7> Tuple7<T1, T2, T3, T4, T5, T6, T7> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7) {
        return new Tuple7<>(v1, v2, v3, v4, v5, v6, v7);
    }

    /**
     * Construct a tuple of degree 8.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8> Tuple8<T1, T2, T3, T4, T5, T6, T7, T8> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8) {
        return new Tuple8<>(v1, v2, v3, v4, v5, v6, v7, v8);
    }

    /**
     * Construct a tuple of degree 9.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9> Tuple9<T1, T2, T3, T4, T5, T6, T7, T8, T9> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9) {
        return new Tuple9<>(v1, v2, v3, v4, v5, v6, v7, v8, v9);
    }

    /**
     * Construct a tuple of degree 10.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> Tuple10<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10) {
        return new Tuple10<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10);
    }

    /**
     * Construct a tuple of degree 11.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11> Tuple11<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11) {
        return new Tuple11<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11);
    }

    /**
     * Construct a tuple of degree 12.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12> Tuple12<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11, T12 v12) {
        return new Tuple12<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12);
    }

    /**
     * Construct a tuple of degree 13.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13> Tuple13<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11, T12 v12, T13 v13) {
        return new Tuple13<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13);
    }

    /**
     * Construct a tuple of degree 14.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14> Tuple14<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11, T12 v12, T13 v13, T14 v14) {
        return new Tuple14<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14);
    }

    /**
     * Construct a tuple of degree 15.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15> Tuple15<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11, T12 v12, T13 v13, T14 v14, T15 v15) {
        return new Tuple15<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15);
    }

    /**
     * Construct a tuple of degree 16.
     */
    public static <T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15, T16> Tuple16<T1, T2, T3, T4, T5, T6, T7, T8, T9, T10, T11, T12, T13, T14, T15, T16> tuple(T1 v1, T2 v2, T3 v3, T4 v4, T5 v5, T6 v6, T7 v7, T8 v8, T9 v9, T10 v10, T11 v11, T12 v12, T13 v13, T14 v14, T15 v15, T16 v16) {
        return new Tuple16<>(v1, v2, v3, v4, v5, v6, v7, v8, v9, v10, v11, v12, v13, v14, v15, v16);
    }

    @Override
    public Tuple<E> clone() {
        return new Tuple<>(this);
    }
}
