/*
 * 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 org.netbeans.modules.parsing.lucene;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
import java.util.regex.Pattern;
import org.apache.lucene.search.Query;
import org.netbeans.api.annotations.common.NonNull;
import org.netbeans.junit.NbTestCase;
import org.netbeans.modules.parsing.lucene.support.Convertor;
import org.netbeans.modules.parsing.lucene.support.DocumentIndex2;
import org.netbeans.modules.parsing.lucene.support.IndexDocument;
import org.netbeans.modules.parsing.lucene.support.IndexManager;
import org.netbeans.modules.parsing.lucene.support.Queries;

/**
 *
 * @author Tomas Zezula
 */
public class DocumentIndexPerfTest extends NbTestCase {

    private static final int NO_RUNS = 0;
    private static final int NO_ROUNDS = 100;
    private static final int ROUND_SIZE = 1_000;

    private final AtomicLong seq = new AtomicLong();

    public DocumentIndexPerfTest(final String name) {
        super(name);
    }

    @Override
    protected void setUp() throws Exception {
        super.setUp();
        clearWorkDir();
    }

    public void testRegExpQuery() throws IOException, InterruptedException {
        if (NO_RUNS > 0) {
            long t = 0L;
            final File indexFolder = getWorkDir();
            for (int cr = 0; cr < NO_RUNS; cr++) {
                deleteContent(indexFolder);
                final DocumentIndex2 index = (DocumentIndex2) IndexManager.createDocumentIndex(indexFolder);
                prepareData(index);
                Query q = Queries.createQuery("bin", "bin", "101.*1", Queries.QueryKind.REGEXP);  //NOI18N
                final Convertor<IndexDocument,Long> c = new IndexDocumentToLong();
                for (int i = 0; i< ROUND_SIZE; i++) {
                    long st = System.nanoTime();
                    index.query(q, c, "bin","hex"); //NOI18N
                    t+= System.nanoTime() - st;
                }
                q = Queries.createQuery("bin", "bin", Pattern.quote("101")+".*1", Queries.QueryKind.REGEXP);  //NOI18N
                for (int i = 0; i< ROUND_SIZE; i++) {
                    long st = System.nanoTime();
                    index.query(q, c, "bin","hex"); //NOI18N
                    t+= System.nanoTime() - st;
                }
                index.close();
            }
            System.out.println("Regexp query: " + (t/(1_000_000 * NO_RUNS)));
        }
    }

    private void prepareData(@NonNull final DocumentIndex2 index) throws IOException {
        for (int i=0; i < NO_ROUNDS; i++) {
            List<Long> data = generateData(ROUND_SIZE);
            addDataToIndex(index, data);
        }
    }

    private List<Long> generateData(int size) {
        final List<Long> res = new ArrayList<>(size);
        for (int i=0; i<size; i++) {
            res.add(seq.incrementAndGet());
        }
        return res;
    }

    private void addDataToIndex(
            @NonNull final DocumentIndex2 index,
            @NonNull final List<Long> data) throws IOException {
        for (long l : data) {
            final IndexDocument doc = IndexManager.createDocument(Long.toString(l));
            doc.addPair("bin", Long.toBinaryString(l), true, true); //NOI18N
            doc.addPair("hex", Long.toHexString(l), true, true);    //NOI18N
            index.addDocument(doc);
        }
        index.store(false);
    }

    private static void deleteContent(File folder) {
        final File[] children = folder.listFiles();
        if (children != null) {
            for (File child : children) {
                if (child.isDirectory()) {
                    deleteContent(child);
                }
                child.delete();
            }
        }
    }

    private static final class IndexDocumentToLong implements Convertor<IndexDocument, Long> {
        @Override
        public Long convert(IndexDocument p) {
            final String hexStr = p.getValue("hex");    //NOI18N
            return Long.valueOf(hexStr, 16);
        }
    }

}