content: /*
   * 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.carbondata.core.profiler;
  
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.concurrent.ConcurrentHashMap;
  
  import org.apache.carbondata.common.annotations.InterfaceAudience;
  import org.apache.carbondata.core.constants.CarbonCommonConstants;
  import org.apache.carbondata.core.index.dev.expr.IndexWrapperSimpleInfo;
  import org.apache.carbondata.core.util.CarbonProperties;
  
  /**
   * An information collector used for EXPLAIN command, to print out
   * SQL rewrite and pruning information.
   * This class is a singleton, not supporting concurrent EXPLAIN command
   */
  @InterfaceAudience.Internal
  public class ExplainCollector {
  
    private static ExplainCollector INSTANCE = null;
  
    private List<String> mvProviders = new ArrayList<>();
    private List<String> mvNames = new ArrayList<>();
  
    // mapping of thread name to map of table name to pruning info
    private Map<String, Map<String, TablePruningInfo>> scans = new ConcurrentHashMap<>();
  
    private ExplainCollector() {
    }
  
    public static boolean enabled() {
      return INSTANCE != null;
    }
  
    public static void setup() {
      boolean isQueryStatisticsEnabled = Boolean.parseBoolean(CarbonProperties.getInstance()
          .getProperty(CarbonCommonConstants.ENABLE_QUERY_STATISTICS,
              CarbonCommonConstants.ENABLE_QUERY_STATISTICS_DEFAULT));
      if (isQueryStatisticsEnabled) {
        INSTANCE = new ExplainCollector();
      }
    }
  
    public static void remove() {
      if (enabled()) {
        INSTANCE = null;
      }
    }
  
    public static ExplainCollector get() {
      return INSTANCE;
    }
  
    public static void addPruningInfo(String tableName) {
      if (enabled()) {
        ExplainCollector profiler = get();
        String threadName = Thread.currentThread().getName();
        if (!profiler.scans.containsKey(threadName)) {
          Map<String, TablePruningInfo> map = new HashMap<>();
          map.put(tableName, new TablePruningInfo());
          profiler.scans.put(threadName, map);
        }
      }
    }
  
    public static void setFilterStatement(String filterStatement) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.setFilterStatement(filterStatement);
      }
    }
  
    public static void setShowPruningInfo(boolean showPruningInfo) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.setShowPruningInfo(showPruningInfo);
      }
    }
  
    public static void addDefaultIndexPruningHit(int numBlocklets) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.addNumBlockletsAfterDefaultPruning(numBlocklets);
      }
    }
  
    public static void setDefaultIndexPruningBlockHit(int numBlocks) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.setNumBlocksAfterDefaultPruning(numBlocks);
      }
    }
  
    public static void recordCGIndexPruning(IndexWrapperSimpleInfo indexWrapperSimpleInfo,
        int numBlocklets, int numBlocks) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.setNumBlockletsAfterCGPruning(indexWrapperSimpleInfo, numBlocklets, numBlocks);
      }
    }
  
    public static void recordFGIndexPruning(IndexWrapperSimpleInfo indexWrapperSimpleInfo,
        int numBlocklets, int numBlocks) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.setNumBlockletsAfterFGPruning(indexWrapperSimpleInfo, numBlocklets, numBlocks);
      }
    }
  
    public static void addTotalBlocklets(int numBlocklets) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.addTotalBlocklets(numBlocklets);
      }
    }
  
    public static void addTotalBlocks(int numBlocks) {
      if (enabled()) {
        TablePruningInfo scan = getCurrentTablePruningInfo();
        scan.addTotalBlocks(numBlocks);
      }
    }
  
    /**
     * Return the current TablePruningInfo (It is the last one in the map, since it is in
     * single thread)
     */
    private static TablePruningInfo getCurrentTablePruningInfo() {
      String threadName = Thread.currentThread().getName();
      if (!get().scans.containsKey(threadName)) {
        throw new IllegalStateException();
      }
  
      Iterator<TablePruningInfo> iterator = get().scans.get(threadName).values().iterator();
      TablePruningInfo output = null;
      while (iterator.hasNext()) {
        output = iterator.next();
      }
      return output;
    }
  
    public static String getFormattedOutput() {
      if (null != get()) {
        return get().toString();
      } else {
        return null;
      }
    }
  
    @Override
    public String toString() {
      StringBuilder builder = new StringBuilder();
      for (int i = 0; i < mvProviders.size(); i++) {
        if (i == 0) {
          builder.append("Query rewrite based on Index:").append("\n");
        }
        builder.append(" - ").append(mvNames.get(i)).append(" (")
            .append(mvProviders.get(i)).append(")").append("\n");
      }
      for (Map.Entry<String, Map<String, TablePruningInfo>> allThreads : scans.entrySet()) {
        for (Map.Entry<String, TablePruningInfo> entry : allThreads.getValue().entrySet()) {
          builder.append("Table Scan on ").append(entry.getKey()).append("\n")
              .append(entry.getValue().toString());
        }
      }
      return builder.toString();
    }
  
  }
  