/*
 * 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.apache.kylin.storage.hbase.cube.v1.filter;

import static org.junit.Assert.assertEquals;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.HBaseTestingUtility;
import org.apache.hadoop.hbase.HConstants;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.Durability;
import org.apache.hadoop.hbase.client.HTable;
import org.apache.hadoop.hbase.client.Put;
import org.apache.hadoop.hbase.client.Result;
import org.apache.hadoop.hbase.client.ResultScanner;
import org.apache.hadoop.hbase.client.Scan;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.FilterList;
import org.apache.hadoop.hbase.filter.FilterList.Operator;
import org.apache.hadoop.hbase.regionserver.ConstantSizeRegionSplitPolicy;
import org.apache.hadoop.hbase.regionserver.HRegion;
import org.apache.hadoop.hbase.regionserver.Region;
import org.apache.hadoop.hbase.regionserver.RegionScanner;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hadoop.hbase.util.Pair;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Ignore;
import org.junit.Test;

import com.google.common.collect.Lists;

@Ignore
public class TestFuzzyRowFilterV2EndToEnd {
    private final static HBaseTestingUtility TEST_UTIL = new HBaseTestingUtility();
    private final static byte fuzzyValue = (byte) 63;
    private static final Log LOG = LogFactory.getLog(TestFuzzyRowFilterV2EndToEnd.class);

    private static int firstPartCardinality = 4;
    private static int secondPartCardinality = 4;
    private static int thirdPartCardinality = 4;
    private static int colQualifiersTotal = 1;
    private static int totalFuzzyKeys = thirdPartCardinality / 2;

    private static String table = "TestFuzzyRowFilterEndToEnd";

    /**
     * @throws java.lang.Exception
     */
    @BeforeClass
    public static void setUpBeforeClass() throws Exception {
        Configuration conf = TEST_UTIL.getConfiguration();
        conf.setInt("hbase.client.scanner.caching", 1000);
        conf.set(HConstants.HBASE_REGION_SPLIT_POLICY_KEY, ConstantSizeRegionSplitPolicy.class.getName());
        // set no splits
        conf.setLong(HConstants.HREGION_MAX_FILESIZE, ((long) 1024) * 1024 * 1024 * 10);

        TEST_UTIL.startMiniCluster();
    }

    /**
     * @throws java.lang.Exception
     */
    @AfterClass
    public static void tearDownAfterClass() throws Exception {
        TEST_UTIL.shutdownMiniCluster();
    }

    /**
     * @throws java.lang.Exception
     */
    @Before
    public void setUp() throws Exception {
        // Nothing to do.
    }

    /**
     * @throws java.lang.Exception
     */
    @After
    public void tearDown() throws Exception {
        // Nothing to do.
    }

    @Test
    public void testEndToEnd() throws Exception {
        String cf = "f";

        HTable ht = TEST_UTIL.createTable(TableName.valueOf(table), Bytes.toBytes(cf), Integer.MAX_VALUE);

        // 10 byte row key - (2 bytes 4 bytes 4 bytes)
        // 4 byte qualifier
        // 4 byte value

        for (int i0 = 0; i0 < firstPartCardinality; i0++) {

            for (int i1 = 0; i1 < secondPartCardinality; i1++) {

                for (int i2 = 0; i2 < thirdPartCardinality; i2++) {
                    byte[] rk = new byte[10];

                    ByteBuffer buf = ByteBuffer.wrap(rk);
                    buf.clear();
                    buf.putShort((short) i0);
                    buf.putInt(i1);
                    buf.putInt(i2);
                    for (int c = 0; c < colQualifiersTotal; c++) {
                        byte[] cq = new byte[4];
                        Bytes.putBytes(cq, 0, Bytes.toBytes(c), 0, 4);

                        Put p = new Put(rk);
                        p.setDurability(Durability.SKIP_WAL);
                        p.addColumn(cf.getBytes(), cq, Bytes.toBytes(c));
                        ht.put(p);
                    }
                }
            }
        }

        TEST_UTIL.flush();

        // test passes
        runTest1(ht);
        runTest2(ht);

    }

    private void runTest1(HTable hTable) throws IOException {
        // [0, 2, ?, ?, ?, ?, 0, 0, 0, 1]

        byte[] mask = new byte[] { 0, 0, 1, 1, 1, 1, 0, 0, 0, 0 };

        List<Pair<byte[], byte[]>> list = new ArrayList<Pair<byte[], byte[]>>();
        for (int i = 0; i < totalFuzzyKeys; i++) {
            byte[] fuzzyKey = new byte[10];
            ByteBuffer buf = ByteBuffer.wrap(fuzzyKey);
            buf.clear();
            buf.putShort((short) 2);
            for (int j = 0; j < 4; j++) {
                buf.put(fuzzyValue);
            }
            buf.putInt(i);

            Pair<byte[], byte[]> pair = Pair.newPair(fuzzyKey, mask);
            list.add(pair);
        }

        int expectedSize = secondPartCardinality * totalFuzzyKeys * colQualifiersTotal;
        FuzzyRowFilterV2 fuzzyRowFilter0 = new FuzzyRowFilterV2(list);
        // Filters are not stateless - we can't reuse them
        FuzzyRowFilterV2 fuzzyRowFilter1 = new FuzzyRowFilterV2(list);

        // regular test
        runScanner(hTable, expectedSize, fuzzyRowFilter0);
        // optimized from block cache
        runScanner(hTable, expectedSize, fuzzyRowFilter1);

    }

    private void runTest2(HTable hTable) throws IOException {
        // [0, 0, ?, ?, ?, ?, 0, 0, 0, 0] , [0, 1, ?, ?, ?, ?, 0, 0, 0, 1]...

        byte[] mask = new byte[] { 0, 0, 1, 1, 1, 1, 0, 0, 0, 0 };

        List<Pair<byte[], byte[]>> list = new ArrayList<Pair<byte[], byte[]>>();

        for (int i = 0; i < totalFuzzyKeys; i++) {
            byte[] fuzzyKey = new byte[10];
            ByteBuffer buf = ByteBuffer.wrap(fuzzyKey);
            buf.clear();
            buf.putShort((short) (i * 2));
            for (int j = 0; j < 4; j++) {
                buf.put(fuzzyValue);
            }
            buf.putInt(i * 2);

            Pair<byte[], byte[]> pair = Pair.newPair(fuzzyKey, mask);
            list.add(pair);
        }

        int expectedSize = totalFuzzyKeys * secondPartCardinality * colQualifiersTotal;

        FuzzyRowFilterV2 fuzzyRowFilter0 = new FuzzyRowFilterV2(list);
        // Filters are not stateless - we can't reuse them
        FuzzyRowFilterV2 fuzzyRowFilter1 = new FuzzyRowFilterV2(list);

        // regular test
        runScanner(hTable, expectedSize, fuzzyRowFilter0);
        // optimized from block cache
        runScanner(hTable, expectedSize, fuzzyRowFilter1);

    }

    private void runScanner(HTable hTable, int expectedSize, Filter filter) throws IOException {

        String cf = "f";
        Scan scan = new Scan();
        scan.addFamily(cf.getBytes());
        scan.setFilter(filter);
        List<HRegion> regions = TEST_UTIL.getHBaseCluster().getRegions(table.getBytes());
        Region first = regions.get(0);
        first.getScanner(scan);
        RegionScanner scanner = first.getScanner(scan);
        List<Cell> results = new ArrayList<Cell>();
        // Result result;
        long timeBeforeScan = System.currentTimeMillis();
        int found = 0;
        while (scanner.next(results)) {
            found += results.size();
            results.clear();
        }
        found += results.size();
        long scanTime = System.currentTimeMillis() - timeBeforeScan;
        scanner.close();

        LOG.info("\nscan time = " + scanTime + "ms");
        LOG.info("found " + found + " results\n");

        assertEquals(expectedSize, found);
    }

    @SuppressWarnings("deprecation")
    @Test
    public void testFilterList() throws Exception {
        String cf = "f";
        String table = "TestFuzzyRowFiltersInFilterList";
        HTable ht = TEST_UTIL.createTable(TableName.valueOf(table), Bytes.toBytes(cf), Integer.MAX_VALUE);

        // 10 byte row key - (2 bytes 4 bytes 4 bytes)
        // 4 byte qualifier
        // 4 byte value

        for (int i1 = 0; i1 < 5; i1++) {
            for (int i2 = 0; i2 < 5; i2++) {
                byte[] rk = new byte[10];

                ByteBuffer buf = ByteBuffer.wrap(rk);
                buf.clear();
                buf.putShort((short) 2);
                buf.putInt(i1);
                buf.putInt(i2);

                // Each row contains 5 columns
                for (int c = 0; c < 5; c++) {
                    byte[] cq = new byte[4];
                    Bytes.putBytes(cq, 0, Bytes.toBytes(c), 0, 4);

                    Put p = new Put(rk);
                    p.setDurability(Durability.SKIP_WAL);
                    p.add(cf.getBytes(), cq, Bytes.toBytes(c));
                    ht.put(p);
                    LOG.info("Inserting: rk: " + Bytes.toStringBinary(rk) + " cq: " + Bytes.toStringBinary(cq));
                }
            }
        }

        TEST_UTIL.flush();

        // test passes if we get back 5 KV's (1 row)
        runTest(ht, 5);

    }

    @SuppressWarnings("unchecked")
    private void runTest(HTable hTable, int expectedSize) throws IOException {
        // [0, 2, ?, ?, ?, ?, 0, 0, 0, 1]
        byte[] fuzzyKey1 = new byte[10];
        ByteBuffer buf = ByteBuffer.wrap(fuzzyKey1);
        buf.clear();
        buf.putShort((short) 2);
        for (int i = 0; i < 4; i++)
            buf.put(fuzzyValue);
        buf.putInt((short) 1);
        byte[] mask1 = new byte[] { 0, 0, 1, 1, 1, 1, 0, 0, 0, 0 };

        byte[] fuzzyKey2 = new byte[10];
        buf = ByteBuffer.wrap(fuzzyKey2);
        buf.clear();
        buf.putShort((short) 2);
        buf.putInt((short) 2);
        for (int i = 0; i < 4; i++)
            buf.put(fuzzyValue);

        byte[] mask2 = new byte[] { 0, 0, 0, 0, 0, 0, 1, 1, 1, 1 };

        Pair<byte[], byte[]> pair1 = Pair.newPair(fuzzyKey1, mask1);
        Pair<byte[], byte[]> pair2 = Pair.newPair(fuzzyKey2, mask2);

        FuzzyRowFilterV2 fuzzyRowFilter1 = new FuzzyRowFilterV2(Lists.newArrayList(pair1));
        FuzzyRowFilterV2 fuzzyRowFilter2 = new FuzzyRowFilterV2(Lists.newArrayList(pair2));
        // regular test - we expect 1 row back (5 KVs)
        runScanner(hTable, expectedSize, fuzzyRowFilter1, fuzzyRowFilter2);
    }

    private void runScanner(HTable hTable, int expectedSize, Filter filter1, Filter filter2) throws IOException {
        String cf = "f";
        Scan scan = new Scan();
        scan.addFamily(cf.getBytes());
        FilterList filterList = new FilterList(Operator.MUST_PASS_ALL, filter1, filter2);
        scan.setFilter(filterList);

        ResultScanner scanner = hTable.getScanner(scan);
        List<Cell> results = new ArrayList<Cell>();
        Result result;
        long timeBeforeScan = System.currentTimeMillis();
        while ((result = scanner.next()) != null) {
            for (Cell kv : result.listCells()) {
                LOG.info("Got rk: " + Bytes.toStringBinary(CellUtil.cloneRow(kv)) + " cq: " + Bytes.toStringBinary(CellUtil.cloneQualifier(kv)));
                results.add(kv);
            }
        }
        long scanTime = System.currentTimeMillis() - timeBeforeScan;
        scanner.close();

        LOG.info("scan time = " + scanTime + "ms");
        LOG.info("found " + results.size() + " results");

        assertEquals(expectedSize, results.size());
    }
}