/*

 * Copyright (c) 2017, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 *

 * This code 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 General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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package jdk.internal.vm.compiler.collections.test;

import java.util.Arrays;

import java.util.Collection;

import java.util.Iterator;

import java.util.LinkedHashMap;

import java.util.Objects;

import java.util.Random;

import jdk.internal.vm.compiler.collections.EconomicMap;

import jdk.internal.vm.compiler.collections.Equivalence;

import jdk.internal.vm.compiler.collections.MapCursor;

import jdk.internal.vm.compiler.collections.UnmodifiableMapCursor;

import org.junit.Assert;

import org.junit.Test;

import org.junit.runner.RunWith;

import org.junit.runners.Parameterized;

import org.junit.runners.Parameterized.Parameter;

import org.junit.runners.Parameterized.Parameters;

@RunWith(Parameterized.class)

public class EconomicMapLargeTest {

    @Parameter(value = 0) public EconomicMap<Object, Object> testMap;

    @Parameter(value = 1) public EconomicMap<Object, Object> referenceMap;

    @Parameter(value = 2) public String name;

    @Parameters(name = "{2}")

    public static Collection<Object[]> data() {

        return Arrays.asList(new Object[]{EconomicMap.create(Equivalence.DEFAULT), EconomicMap.create(Equivalence.DEFAULT), "EconomicMap"},

                        new Object[]{EconomicMap.create(Equivalence.IDENTITY), EconomicMap.create(Equivalence.IDENTITY), "EconomicMap(IDENTITY)"},

                        new Object[]{EconomicMap.create(Equivalence.IDENTITY_WITH_SYSTEM_HASHCODE), EconomicMap.create(Equivalence.IDENTITY_WITH_SYSTEM_HASHCODE),

                                        "EconomicMap(IDENTITY_WITH_SYSTEM_HASHCODE)"},

                        new Object[]{EconomicMap.create(Equivalence.DEFAULT), EconomicMap.wrapMap(new LinkedHashMap<>()), "EconomicMap<->wrapMap"},

                        new Object[]{EconomicMap.wrapMap(new LinkedHashMap<>()), EconomicMap.wrapMap(new LinkedHashMap<>()), "wrapMap"});

    }

    private static int[] createRandomRange(Random random, int count) {

        int[] result = new int[count];

        for (int i = 0; i < count; ++i) {

            int range = random.nextInt(14);

            if (range == 0 || range > 10) {

                range = Integer.MAX_VALUE;

            } else if (range == 10) {

                range = 100;

            }

            result[i] = range;

        }

        return result;

    }

    private static final class BadHashClass {

        private int value;

        BadHashClass(int randomInt) {

            this.value = randomInt;

        }

        @Override

        public int hashCode() {

            return 0;

        }

        @Override

        public boolean equals(Object other) {

            if (other instanceof BadHashClass) {

                BadHashClass badHashClass = (BadHashClass) other;

                return badHashClass.value == value;

            }

            return false;

        }

    }

    interface MapAction {

        Object perform(EconomicMap<Object, Object> map, int randomInt);

    }

    static final Object EXISTING_VALUE = new Object();

    static final MapAction[] INCREASE_ACTIONS = new MapAction[]{

                    (map, randomInt) -> map.put(randomInt, "value"),

                    (map, randomInt) -> map.get(randomInt)

    };

    static final MapAction[] ACTIONS = new MapAction[]{

                    (map, randomInt) -> map.removeKey(randomInt),

                    (map, randomInt) -> map.put(randomInt, "value"),

                    (map, randomInt) -> map.put(randomInt, null),

                    (map, randomInt) -> map.put(EXISTING_VALUE, randomInt),

                    (map, randomInt) -> {

                        if (randomInt == 0) {

                            map.clear();

                        }

                        return map.isEmpty();

                    },

                    (map, randomInt) -> map.containsKey(randomInt),

                    (map, randomInt) -> map.get(randomInt),

                    (map, randomInt) -> map.put(new BadHashClass(randomInt), "unique"),

                    (map, randomInt) -> {

                        if (randomInt == 0) {

                            map.replaceAll((key, value) -> Objects.toString(value) + "!");

                        }

                        return map.isEmpty();

                    }

    };

    @Test

    public void testVeryLarge() {

        testMap.clear();

        referenceMap.clear();

        Random random = new Random(0);

        for (int i = 0; i < 200000; ++i) {

            for (int j = 0; j < INCREASE_ACTIONS.length; ++j) {

                int nextInt = random.nextInt(10000000);

                MapAction action = INCREASE_ACTIONS[j];

                Object result = action.perform(testMap, nextInt);

                Object referenceResult = action.perform(referenceMap, nextInt);

                Assert.assertEquals(result, referenceResult);

            }

        }

    }

    /**

     * Tests a sequence of random operations on the map.

     */

    @Test

    public void testAddRemove() {

        testMap.clear();

        referenceMap.clear();

        for (int seed = 0; seed < 10; ++seed) {

            Random random = new Random(seed);

            int[] ranges = createRandomRange(random, ACTIONS.length);

            int value = random.nextInt(10000);

            for (int i = 0; i < value; ++i) {

                for (int j = 0; j < ACTIONS.length; ++j) {

                    if (random.nextInt(ranges[j]) == 0) {

                        int nextInt = random.nextInt(100);

                        MapAction action = ACTIONS[j];

                        Object result = action.perform(testMap, nextInt);

                        Object referenceResult = action.perform(referenceMap, nextInt);

                        Assert.assertEquals(result, referenceResult);

                        if (j % 100 == 0) {

                            checkEquality(testMap, referenceMap);

                        }

                    }

                }

                if (random.nextInt(20) == 0) {

                    removeElement(random.nextInt(100), testMap, referenceMap);

                }

            }

        }

    }

    private static void removeElement(int index, EconomicMap<?, ?> map, EconomicMap<?, ?> referenceMap) {

        Assert.assertEquals(referenceMap.size(), map.size());

        MapCursor<?, ?> cursor = map.getEntries();

        MapCursor<?, ?> referenceCursor = referenceMap.getEntries();

        int z = 0;

        while (cursor.advance()) {

            Assert.assertTrue(referenceCursor.advance());

            Assert.assertEquals(referenceCursor.getKey(), cursor.getKey());

            Assert.assertEquals(referenceCursor.getValue(), cursor.getValue());

            if (index == z) {

                cursor.remove();

                referenceCursor.remove();

            }

            ++z;

        }

        Assert.assertFalse(referenceCursor.advance());

    }

    private static void checkEquality(EconomicMap<?, ?> map, EconomicMap<?, ?> referenceMap) {

        Assert.assertEquals(referenceMap.size(), map.size());

        // Check entries.

        UnmodifiableMapCursor<?, ?> cursor = map.getEntries();

        UnmodifiableMapCursor<?, ?> referenceCursor = referenceMap.getEntries();

        while (cursor.advance()) {

            Assert.assertTrue(referenceCursor.advance());

            Assert.assertEquals(referenceCursor.getKey(), cursor.getKey());

            Assert.assertEquals(referenceCursor.getValue(), cursor.getValue());

        }

        // Check keys.

        Iterator<?> iterator = map.getKeys().iterator();

        Iterator<?> referenceIterator = referenceMap.getKeys().iterator();

        while (iterator.hasNext()) {

            Assert.assertTrue(referenceIterator.hasNext());

            Assert.assertEquals(iterator.next(), referenceIterator.next());

        }

        // Check values.

        iterator = map.getValues().iterator();

        referenceIterator = referenceMap.getValues().iterator();

        while (iterator.hasNext()) {

            Assert.assertTrue(referenceIterator.hasNext());

            Assert.assertEquals(iterator.next(), referenceIterator.next());

        }

        Assert.assertFalse(referenceIterator.hasNext());

    }

}