content: /*
   * Copyright 1999-2017 Alibaba Group Holding Ltd.
   *
   * 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.druid.sql.dialect.h2.parser;
  
  import com.alibaba.druid.sql.ast.expr.SQLDefaultExpr;
  import com.alibaba.druid.sql.ast.expr.SQLIdentifierExpr;
  import com.alibaba.druid.sql.ast.expr.SQLIntegerExpr;
  import com.alibaba.druid.sql.ast.statement.SQLColumnDefinition;
  import com.alibaba.druid.sql.parser.*;
  import com.alibaba.druid.util.FnvHash;
  
  import java.util.Arrays;
  
  public class H2ExprParser extends SQLExprParser {
      private static final String[] AGGREGATE_FUNCTIONS;
      private static final long[] AGGREGATE_FUNCTIONS_CODES;
  
      static {
          String[] strings = {"AVG", "COUNT", "MAX", "MIN", "STDDEV", "SUM", "ROW_NUMBER",
                  "ROWNUMBER"};
          AGGREGATE_FUNCTIONS_CODES = FnvHash.fnv1a_64_lower(strings, true);
          AGGREGATE_FUNCTIONS = new String[AGGREGATE_FUNCTIONS_CODES.length];
          for (String str : strings) {
              long hash = FnvHash.fnv1a_64_lower(str);
              int index = Arrays.binarySearch(AGGREGATE_FUNCTIONS_CODES, hash);
              AGGREGATE_FUNCTIONS[index] = str;
          }
      }
  
      public H2ExprParser(String sql) {
          this(new H2Lexer(sql));
          this.lexer.nextToken();
      }
  
      public H2ExprParser(String sql, SQLParserFeature... features) {
          this(new H2Lexer(sql, features));
          this.lexer.nextToken();
      }
  
      public H2ExprParser(Lexer lexer) {
          super(lexer);
          dbType = lexer.getDbType();
          this.aggregateFunctions = AGGREGATE_FUNCTIONS;
          this.aggregateFunctionHashCodes = AGGREGATE_FUNCTIONS_CODES;
      }
  
      public SQLColumnDefinition parseColumnRest(SQLColumnDefinition column) {
          column = super.parseColumnRest(column);
  
          if (lexer.identifierEquals(FnvHash.Constants.GENERATED)) {
              lexer.nextToken();
              if (lexer.token() == Token.BY) {
                  lexer.nextToken();
                  accept(Token.DEFAULT);
                  column.setGeneratedAlwaysAs(new SQLDefaultExpr());
              } else {
                  acceptIdentifier("ALWAYS");
                  column.setGeneratedAlwaysAs(new SQLIdentifierExpr("ALWAYS"));
              }
              accept(Token.AS);
              acceptIdentifier("IDENTITY");
  
              SQLColumnDefinition.Identity identity = new SQLColumnDefinition.Identity();
              if (lexer.token() == Token.LPAREN) {
                  lexer.nextToken();
  
                  SQLIntegerExpr seed = (SQLIntegerExpr) this.primary();
                  accept(Token.COMMA);
                  SQLIntegerExpr increment = (SQLIntegerExpr) this.primary();
                  accept(Token.RPAREN);
  
                  identity.setSeed((Integer) seed.getNumber());
                  identity.setIncrement((Integer) increment.getNumber());
              }
              column.setIdentity(identity);
          }
  
          return column;
      }
  
      protected SQLColumnDefinition.Identity parseIdentity0() {
          SQLColumnDefinition.Identity identity = new SQLColumnDefinition.Identity();
  
          accept(Token.IDENTITY);
          if (lexer.token() == Token.LPAREN) {
              accept(Token.LPAREN);
  
              if (lexer.identifierEquals(FnvHash.Constants.START)) {
                  lexer.nextToken();
                  accept(Token.WITH);
                  if (lexer.token() == Token.LITERAL_INT) {
                      identity.setSeed((Integer) lexer.integerValue());
                      lexer.nextToken();
                  } else {
                      throw new ParserException("TODO " + lexer.info());
                  }
  
                  if (lexer.token() == Token.COMMA) {
                      lexer.nextToken();
                  }
              }
  
              if (lexer.identifierEquals(FnvHash.Constants.INCREMENT)) {
                  lexer.nextToken();
                  accept(Token.BY);
                  if (lexer.token() == Token.LITERAL_INT) {
                      identity.setIncrement((Integer) lexer.integerValue());
                      lexer.nextToken();
                  } else {
                      throw new ParserException("TODO " + lexer.info());
                  }
  
                  if (lexer.token() == Token.COMMA) {
                      lexer.nextToken();
                  }
              }
  
              if (lexer.identifierEquals(FnvHash.Constants.CYCLE)) {
                  lexer.nextToken();
                  identity.setCycle(true);
  
                  if (lexer.token() == Token.COMMA) {
                      lexer.nextToken();
                  }
              }
  
              if (lexer.identifierEquals(FnvHash.Constants.MINVALUE)) {
                  lexer.nextTokenValue();
                  if (lexer.token() == Token.LITERAL_INT) {
                      identity.setMinValue((Integer) lexer.integerValue());
                      lexer.nextToken();
                  } else {
                      throw new ParserException("TODO " + lexer.info());
                  }
  
                  if (lexer.token() == Token.COMMA) {
                      lexer.nextToken();
                  }
              }
  
              if (lexer.identifierEquals(FnvHash.Constants.MAXVALUE)) {
                  lexer.nextToken();
                  if (lexer.token() == Token.LITERAL_INT) {
                      identity.setMaxValue((Integer) lexer.integerValue());
                      lexer.nextToken();
                  } else {
                      throw new ParserException("TODO " + lexer.info());
                  }
  
                  if (lexer.token() == Token.COMMA) {
                      lexer.nextToken();
                  }
              }
  
              accept(Token.RPAREN);
          }
  
          return identity;
      }
  }
  