/*
    * 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.hadoop.chukwa.database;
  
  
  import java.sql.ResultSet;
  import java.sql.SQLException;
  import java.text.SimpleDateFormat;
  import java.util.Date;
  import java.util.HashMap;
  import java.util.Map.Entry;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  import org.apache.hadoop.chukwa.util.DatabaseWriter;
  import org.apache.hadoop.chukwa.util.ExceptionUtil;
  import org.apache.hadoop.chukwa.util.RegexUtil;
  
  public class TableCreator {
    private static DatabaseConfig dbc = null;
    private static Log log = LogFactory.getLog(TableCreator.class);
  
    public TableCreator() {
      if (dbc == null) {
        dbc = new DatabaseConfig();
      }
    }
  
    public void createTables() throws Exception {
      long now = (new Date()).getTime();
      createTables(now, now);
    }
  
    @edu.umd.cs.findbugs.annotations.SuppressWarnings(value =
        "SQL_NONCONSTANT_STRING_PASSED_TO_EXECUTE", 
        justification = "Dynamic based upon tables in the database")
    public void createTables(long start, long end) throws Exception {
      String cluster = System.getProperty("CLUSTER");
      if (cluster == null) {
        cluster = "unknown";
      }
      DatabaseWriter dbw = new DatabaseWriter(cluster);
      HashMap<String, String> dbNames = dbc.startWith("report.db.name.");
      for(Entry<String, String> entry : dbNames.entrySet()) {
        String tableName = entry.getValue();
        if (!RegexUtil.isRegex(tableName)) {
          log.warn("Skipping tableName: '" + tableName
              + "' because there was an error parsing it as a regex: "
              + RegexUtil.regexError(tableName));
          return;
        }
        String[] tableList = dbc.findTableName(tableName, start, end);
        log.debug("table name: " + tableList[0]);
        try {
          String[] parts = tableList[0].split("_");
          int partition = Integer.parseInt(parts[parts.length - 2]);
          StringBuilder tableNameBuffer = new StringBuilder();
          for (int i = 0; i < parts.length - 2; i++) {
            if (i != 0) {
              tableNameBuffer.append("_");
            }
            tableNameBuffer.append(parts[i]);
          }
          String table = tableNameBuffer.toString();
          StringBuilder q = new StringBuilder();
          q.append("show create table ");
          q.append(table);
          q.append("_template;");
          final String query = q.toString();
          ResultSet rs = dbw.query(query);
          while (rs.next()) {
            log.debug("table schema: " + rs.getString(2));
            String tbl = rs.getString(2);
            log.debug("template table name:" + table + "_template");
            log.debug("replacing with table name:" + table + "_" + partition
                + "_" + parts[parts.length - 1]);
            log.debug("creating table: " + tbl);
            
            for(int i=0;i<2;i++) {
              StringBuilder templateName = new StringBuilder();
              templateName.append(table);
              templateName.append("_template");
              StringBuilder partitionName = new StringBuilder();
             partitionName.append(table);
             partitionName.append("_");
             partitionName.append(partition);
             partitionName.append("_");
             partitionName.append(parts[parts.length - 1]);
             tbl = tbl.replaceFirst("TABLE", "TABLE IF NOT EXISTS");
             tbl = tbl.replaceFirst(templateName.toString(), partitionName.toString());
             final String createTable = tbl;
             dbw.execute(createTable);
             partition++;
           }
         }
       } catch (NumberFormatException e) {
         log.error("Error in parsing table partition number, skipping table:"
             + tableList[0]);
       } catch (ArrayIndexOutOfBoundsException e) {
         log.debug("Skipping table:" + tableList[0]
             + ", because it has no partition configuration.");
       } catch (SQLException e) {
         throw e;
       }
     }
   }
 
   public static void usage() {
     System.out.println("TableCreator usage:");
     System.out
         .println("java -jar chukwa-core.jar org.apache.hadoop.chukwa.TableCreator <date> <time window size>");
     System.out.println("     date format: YYYY-MM-DD");
     System.out.println("     time window size: 7, 30, 91, 365, 3650");
   }
 
   public static void main(String[] args) {
     TableCreator tc = new TableCreator();
     if (args.length == 2) {
       try {
         SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
         long start = sdf.parse(args[0]).getTime();
         long end = start + (Long.parseLong(args[1]) * 1440 * 60 * 1000L);
         tc.createTables(start, end);
       } catch (Exception e) {
         System.out.println("Invalid date format or time window size.");
         e.printStackTrace();
         usage();
       }
     } else {
       try {
         tc.createTables();
       } catch (Exception e) {
         log.error(ExceptionUtil.getStackTrace(e));
       }
     }
 
   }
 }