/*
 * Copyright (C) 2014 Indeed Inc.
 *
 * 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 com.indeed.flamdex.query;

import com.google.common.collect.ImmutableList;
import org.junit.Test;

import java.util.List;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;

/**
 * @author dwahler
 */
public class TestQuery {
    @Test
    public void testEqualsHashCode() {
        @SuppressWarnings("unchecked")
        List<List<Query>> equivalenceClasses = ImmutableList.<List<Query>>of(
                ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, "foo")),
                        Query.newTermQuery(new Term("abc", true, 123, "bar"))),
                ImmutableList.of(
                        Query.newTermQuery(new Term("abc", false, 0, "foo")),
                        Query.newTermQuery(new Term("abc", false, 123, "foo"))),
                ImmutableList.of(
                        Query.newTermQuery(new Term("abc", false, 123, "bar"))),

                ImmutableList.of(Query.newRangeQuery("foo", 123, 456, true)),
                ImmutableList.of(Query.newRangeQuery("foo", 123, 456, false)),
                ImmutableList.of(Query.newRangeQuery("foo", "123", "456", true)),
                ImmutableList.of(Query.newRangeQuery("foo", "123", "456", false)),

                ImmutableList.of(Query.newBooleanQuery(BooleanOp.AND, ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, ""))))),
                ImmutableList.of(Query.newBooleanQuery(BooleanOp.AND, ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, "")),
                        Query.newTermQuery(new Term("abc", true, 456, ""))))),
                ImmutableList.of(Query.newBooleanQuery(BooleanOp.OR, ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, ""))))),
                ImmutableList.of(Query.newBooleanQuery(BooleanOp.OR, ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, "")),
                        Query.newTermQuery(new Term("abc", true, 456, ""))))),
                ImmutableList.of(Query.newBooleanQuery(BooleanOp.NOT, ImmutableList.of(
                        Query.newTermQuery(new Term("abc", true, 123, "")))))
        );

        int hashCollisions = 0, hashComparisons = 0;

        for (List<Query> group1 : equivalenceClasses) {
            for (List<Query> group2 : equivalenceClasses) {

                for (Query a : group1) {
                    for (Query b : group2) {

                        if (group1 == group2) {
                            // assert equality within class
                            assertEquals(a, b);
                            assertEquals(a.hashCode(), b.hashCode());
                        } else {
                            // assert non-equivalence with other classes
                            assertFalse(a + " equals " + b, a.equals(b));
                            if (a.hashCode() == b.hashCode()) {
                                hashCollisions++;
                            }
                            hashComparisons++;
                        }

                    }
                }

            }
        }

        System.out.printf("hash collisions occurred for %d out of %d comparisons\n", hashCollisions, hashComparisons);
    }
}
