/*
 * SPDX-License-Identifier: Apache-2.0
 *
 * The OpenSearch Contributors require contributions made to
 * this file be licensed under the Apache-2.0 license or a
 * compatible open source license.
 */

/*
 * Licensed to Elasticsearch under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch 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.
 */

/*
 * Modifications Copyright OpenSearch Contributors. See
 * GitHub history for details.
 */

package org.opensearch.index.fielddata;

import org.opensearch.index.fielddata.ScriptDocValues.Longs;
import org.opensearch.test.OpenSearchTestCase;

import java.io.IOException;

public class ScriptDocValuesLongsTests extends OpenSearchTestCase {
    public void testLongs() throws IOException {
        long[][] values = new long[between(3, 10)][];
        for (int d = 0; d < values.length; d++) {
            values[d] = new long[randomBoolean() ? randomBoolean() ? 0 : 1 : between(2, 100)];
            for (int i = 0; i < values[d].length; i++) {
                values[d][i] = randomLong();
            }
        }

        Longs longs = wrap(values);

        for (int round = 0; round < 10; round++) {
            int d = between(0, values.length - 1);
            longs.setNextDocId(d);
            if (values[d].length > 0) {
                assertEquals(values[d][0], longs.getValue());
                assertEquals(values[d][0], (long) longs.get(0));
            } else {
                Exception e = expectThrows(IllegalStateException.class, () -> longs.getValue());
                assertEquals(
                    "A document doesn't have a value for a field! "
                        + "Use doc[<field>].size()==0 to check if a document is missing a field!",
                    e.getMessage()
                );
                e = expectThrows(IllegalStateException.class, () -> longs.get(0));
                assertEquals(
                    "A document doesn't have a value for a field! "
                        + "Use doc[<field>].size()==0 to check if a document is missing a field!",
                    e.getMessage()
                );
            }
            assertEquals(values[d].length, longs.size());
            for (int i = 0; i < values[d].length; i++) {
                assertEquals(values[d][i], longs.get(i).longValue());
            }

            Exception e = expectThrows(UnsupportedOperationException.class, () -> longs.add(100L));
            assertEquals("doc values are unmodifiable", e.getMessage());
        }
    }

    private Longs wrap(long[][] values) {
        return new Longs(new AbstractSortedNumericDocValues() {
            long[] current;
            int i;

            @Override
            public boolean advanceExact(int doc) {
                i = 0;
                current = values[doc];
                return current.length > 0;
            }

            @Override
            public int docValueCount() {
                return current.length;
            }

            @Override
            public long nextValue() {
                return current[i++];
            }
        });
    }
}