content: /*
   * Copyright 1999-2012 Alibaba Group.
   *  
   * Licensed 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 com.alibaba.cobar.manager.parser;
  
  import com.alibaba.cobar.parser.util.ParseUtil;
  
  /**
   * @author xianmao.hexm
   * @author wenfeng.cenwf 2011-4-19
   */
  public final class ManagerParse {
  
      public static final int OTHER = -1;
      public static final int SELECT = 1;
      public static final int SET = 2;
      public static final int SHOW = 3;
      public static final int SWITCH = 4;
      public static final int KILL_CONN = 5;
      public static final int STOP = 6;
      public static final int RELOAD = 7;
      public static final int ROLLBACK = 8;
      public static final int OFFLINE = 9;
      public static final int ONLINE = 10;
      public static final int CLEAR = 11;
  
      public static int parse(String stmt) {
          for (int i = 0; i < stmt.length(); i++) {
              switch (stmt.charAt(i)) {
              case ' ':
                  continue;
              case '/':
              case '#':
                  i = ParseUtil.comment(stmt, i);
                  continue;
              case 'C':
              case 'c':
                  return cCheck(stmt, i);
              case 'S':
              case 's':
                  return sCheck(stmt, i);
              case 'K':
              case 'k':
                  return kill(stmt, i);
              case 'O':
              case 'o':
                  return oCheck(stmt, i);
              case 'R':
              case 'r':
                  return rCheck(stmt, i);
              default:
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      // CLEAR
      private static int cCheck(String stmt, int offset) {
          if (stmt.length() > offset + "LEAR ".length()) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              if ((c1 == 'L' || c1 == 'l') && (c2 == 'E' || c2 == 'e') && (c3 == 'A' || c3 == 'a')
                      && (c4 == 'R' || c4 == 'r') && (c5 == ' ' || c5 == '\t' || c5 == '\r' || c5 == '\n')) {
                  return (offset << 8) | CLEAR;
              }
          }
          return OTHER;
      }
  
      private static int oCheck(String stmt, int offset) {
          if (stmt.length() > ++offset) {
              switch (stmt.charAt(offset)) {
              case 'F':
              case 'f':
                  return ofCheck(stmt, offset);
              case 'N':
              case 'n':
                  return onCheck(stmt, offset);
              default:
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      private static int onCheck(String stmt, int offset) {
          if (stmt.length() > offset + "line".length()) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              if ((c1 == 'l' || c1 == 'L') && (c2 == 'i' || c2 == 'I') && (c3 == 'n' || c3 == 'N')
                      && (c4 == 'e' || c4 == 'E') && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                  return ONLINE;
              }
          }
          return OTHER;
      }
  
      private static int ofCheck(String stmt, int offset) {
          if (stmt.length() > offset + "fline".length()) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              if ((c1 == 'f' || c1 == 'F') && (c2 == 'l' || c2 == 'L') && (c3 == 'i' || c3 == 'I')
                      && (c4 == 'n' || c4 == 'N') && (c5 == 'e' || c5 == 'E')
                      && (stmt.length() == ++offset || ParseUtil.isEOF(stmt.charAt(offset)))) {
                  return OFFLINE;
              }
          }
          return OTHER;
      }
  
      private static int sCheck(String stmt, int offset) {
          if (stmt.length() > ++offset) {
              switch (stmt.charAt(offset)) {
              case 'E':
              case 'e':
                  return seCheck(stmt, offset);
              case 'H':
              case 'h':
                  return show(stmt, offset);
              case 'W':
              case 'w':
                  return swh(stmt, offset);
              case 'T':
              case 't':
                  return stop(stmt, offset);
              default:
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      private static int seCheck(String stmt, int offset) {
          if (stmt.length() > ++offset) {
              switch (stmt.charAt(offset)) {
              case 'L':
              case 'l':
                  return select(stmt, offset);
              case 'T':
              case 't':
                  if (stmt.length() > ++offset) {
                      char c = stmt.charAt(offset);
                      if (c == ' ' || c == '\r' || c == '\n' || c == '\t' || c == '/' || c == '#') {
                          return SET;
                      }
                  }
                  return OTHER;
              default:
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      private static int rCheck(String stmt, int offset) {
          if (stmt.length() > ++offset) {
              switch (stmt.charAt(offset)) {
              case 'E':
              case 'e':
                  return reload(stmt, offset);
              case 'O':
              case 'o':
                  return rollback(stmt, offset);
              default:
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      // RELOAD' '
      private static int reload(String stmt, int offset) {
          if (stmt.length() > offset + 5) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              if ((c1 == 'L' || c1 == 'l') && (c2 == 'O' || c2 == 'o') && (c3 == 'A' || c3 == 'a')
                      && (c4 == 'D' || c4 == 'd') && (c5 == ' ' || c5 == '\t' || c5 == '\r' || c5 == '\n')) {
                  return (offset << 8) | RELOAD;
              }
          }
          return OTHER;
      }
  
      // ROLLBACK' '
      private static int rollback(String stmt, int offset) {
          if (stmt.length() > offset + 7) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              char c6 = stmt.charAt(++offset);
              char c7 = stmt.charAt(++offset);
              if ((c1 == 'L' || c1 == 'l') && (c2 == 'L' || c2 == 'l') && (c3 == 'B' || c3 == 'b')
                      && (c4 == 'A' || c4 == 'a') && (c5 == 'C' || c5 == 'c') && (c6 == 'K' || c6 == 'k')
                      && (c7 == ' ' || c7 == '\t' || c7 == '\r' || c7 == '\n')) {
                  return (offset << 8) | ROLLBACK;
              }
          }
          return OTHER;
      }
  
      // SELECT' '
      private static int select(String stmt, int offset) {
          if (stmt.length() > offset + 4) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              if ((c1 == 'E' || c1 == 'e') && (c2 == 'C' || c2 == 'c') && (c3 == 'T' || c3 == 't')
                      && (c4 == ' ' || c4 == '\t' || c4 == '\r' || c4 == '\n')) {
                  return (offset << 8) | SELECT;
              }
          }
          return OTHER;
      }
  
      // SHOW' '
      private static int show(String stmt, int offset) {
          if (stmt.length() > offset + 3) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              if ((c1 == 'O' || c1 == 'o') && (c2 == 'W' || c2 == 'w')
                      && (c3 == ' ' || c3 == '\t' || c3 == '\r' || c3 == '\n')) {
                  return (offset << 8) | SHOW;
              }
          }
          return OTHER;
      }
  
      // SWITCH' '
      private static int swh(String stmt, int offset) {
          if (stmt.length() > offset + 5) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              if ((c1 == 'I' || c1 == 'i') && (c2 == 'T' || c2 == 't') && (c3 == 'C' || c3 == 'c')
                      && (c4 == 'H' || c4 == 'h') && (c5 == ' ' || c5 == '\t' || c5 == '\r' || c5 == '\n')) {
                  return (offset << 8) | SWITCH;
              }
          }
          return OTHER;
      }
  
      // STOP' '
      private static int stop(String stmt, int offset) {
          if (stmt.length() > offset + 3) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              if ((c1 == 'O' || c1 == 'o') && (c2 == 'P' || c2 == 'p')
                      && (c3 == ' ' || c3 == '\t' || c3 == '\r' || c3 == '\n')) {
                  return (offset << 8) | STOP;
              }
          }
          return OTHER;
      }
  
      // KILL @
      private static int kill(String stmt, int offset) {
          if (stmt.length() > offset + 3) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              if ((c1 == 'I' || c1 == 'i') && (c2 == 'L' || c2 == 'l') && (c3 == 'L' || c3 == 'l')
                      && (c4 == ' ' || c4 == '\t' || c4 == '\r' || c4 == '\n')) {
                  while (stmt.length() > ++offset) {
                      switch (stmt.charAt(offset)) {
                      case ' ':
                      case '\t':
                      case '\r':
                      case '\n':
                          continue;
                      case '@':
                          return killConnection(stmt, offset);
                      default:
                          return OTHER;
                      }
                  }
                  return OTHER;
              }
          }
          return OTHER;
      }
  
      // KILL @@CONNECTION' ' XXXXXX
      private static int killConnection(String stmt, int offset) {
          if (stmt.length() > offset + "@CONNECTION ".length()) {
              char c1 = stmt.charAt(++offset);
              char c2 = stmt.charAt(++offset);
              char c3 = stmt.charAt(++offset);
              char c4 = stmt.charAt(++offset);
              char c5 = stmt.charAt(++offset);
              char c6 = stmt.charAt(++offset);
              char c7 = stmt.charAt(++offset);
              char c8 = stmt.charAt(++offset);
              char c9 = stmt.charAt(++offset);
              char c10 = stmt.charAt(++offset);
              char c11 = stmt.charAt(++offset);
              char c12 = stmt.charAt(++offset);
              if ((c1 == '@') && (c2 == 'C' || c2 == 'c') && (c3 == 'O' || c3 == 'o') && (c4 == 'N' || c4 == 'n')
                      && (c5 == 'N' || c5 == 'n') && (c6 == 'E' || c6 == 'e') && (c7 == 'C' || c7 == 'c')
                      && (c8 == 'T' || c8 == 't') && (c9 == 'I' || c9 == 'i') && (c10 == 'O' || c10 == 'o')
                      && (c11 == 'N' || c11 == 'n') && (c12 == ' ' || c12 == '\t' || c12 == '\r' || c12 == '\n')) {
                  while (stmt.length() > ++offset) {
                      switch (stmt.charAt(offset)) {
                      case ' ':
                      case '\t':
                      case '\r':
                      case '\n':
                          continue;
                      default:
                          return (offset << 8) | KILL_CONN;
                      }
                  }
              }
          }
          return OTHER;
      }
  
  }
  