/*
 * Copyright 2015, 2019 StreamEx contributors
 *
 * 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 one.util.streamex;

import java.util.Arrays;
import java.util.Spliterator;

import org.junit.Test;

import one.util.streamex.PairSpliterator.PSOfRef;

import static one.util.streamex.TestHelpers.checkSpliterator;
import static one.util.streamex.TestHelpers.withRandom;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

/**
 * @author Tagir Valeev
 */
public class PairSpliteratorTest {
    @Test
    public void testSpliterator() {
        withRandom(r -> {
            int[] ints = IntStreamEx.of(r, 100).toArray();
            long[] longs = LongStreamEx.of(r, 100).toArray();
            double[] doubles = DoubleStreamEx.of(r, 100).toArray();

            checkSpliterator("ref", () -> new PairSpliterator.PSOfRef<>((a, b) -> (a - b), Arrays.spliterator(ints)));
            checkSpliterator("int", () -> new PairSpliterator.PSOfInt((a, b) -> (a - b), null, Arrays.spliterator(ints), PairSpliterator.MODE_PAIRS));
            checkSpliterator("long", () -> new PairSpliterator.PSOfLong((a, b) -> (a - b), null, Arrays.spliterator(longs), PairSpliterator.MODE_PAIRS));
            checkSpliterator("double", () -> new PairSpliterator.PSOfDouble((a, b) -> (a - b), null, Arrays.spliterator(doubles), PairSpliterator.MODE_PAIRS));
            
            // mapFirst
            checkSpliterator("ref", IntStreamEx.of(ints, 1, ints.length).boxed().prepend(ints[0] + 2).toList(),
                () -> new PairSpliterator.PSOfRef<>(a -> a + 2, Arrays.spliterator(ints), true));
            checkSpliterator("int", IntStreamEx.of(ints, 1, ints.length).boxed().prepend(ints[0] + 2).toList(),
                () -> new PairSpliterator.PSOfInt((a, b) -> b, a -> a + 2, Arrays.spliterator(ints), PairSpliterator.MODE_MAP_FIRST));
            checkSpliterator("long", LongStreamEx.of(longs, 1, longs.length).boxed().prepend(longs[0] + 2).toList(),
                () -> new PairSpliterator.PSOfLong((a, b) -> b, a -> a + 2, Arrays.spliterator(longs), PairSpliterator.MODE_MAP_FIRST));
            checkSpliterator("double", DoubleStreamEx.of(doubles, 1, doubles.length).boxed().prepend(doubles[0] + 2).toList(),
                () -> new PairSpliterator.PSOfDouble((a, b) -> b, a -> a + 2, Arrays.spliterator(doubles), PairSpliterator.MODE_MAP_FIRST));
            
            // mapLast
            checkSpliterator("ref", IntStreamEx.of(ints, 0, ints.length - 1).boxed().append(ints[ints.length - 1] + 2).toList(),
                () -> new PairSpliterator.PSOfRef<>(a -> a + 2, Arrays.spliterator(ints), false));
            checkSpliterator("int", IntStreamEx.of(ints, 0, ints.length - 1).boxed().append(ints[ints.length - 1] + 2).toList(),
                () -> new PairSpliterator.PSOfInt((a, b) -> a, a -> a + 2, Arrays.spliterator(ints), PairSpliterator.MODE_MAP_LAST));
            checkSpliterator("long", LongStreamEx.of(longs, 0, longs.length - 1).boxed().append(longs[longs.length - 1] + 2).toList(),
                () -> new PairSpliterator.PSOfLong((a, b) -> a, a -> a + 2, Arrays.spliterator(longs), PairSpliterator.MODE_MAP_LAST));
            checkSpliterator("double", DoubleStreamEx.of(doubles, 0, doubles.length - 1).boxed().append(doubles[doubles.length - 1] + 2).toList(),
                () -> new PairSpliterator.PSOfDouble((a, b) -> a, a -> a + 2, Arrays.spliterator(doubles), PairSpliterator.MODE_MAP_LAST));
        });
    }
    
    @Test
    public void testCharacteristics() {
        PSOfRef<Integer, Integer> ps = new PairSpliterator.PSOfRef<>((a, b) -> (a - b), IntStreamEx.range(100).spliterator());
        assertTrue(ps.hasCharacteristics(Spliterator.SIZED));
        assertTrue(ps.hasCharacteristics(Spliterator.ORDERED));
        assertTrue(ps.hasCharacteristics(Spliterator.IMMUTABLE));
        assertEquals(99, ps.getExactSizeIfKnown());
    }
}
