/*
    *    Copyright 2006-2023 the original author or authors.
    *
    *    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
    *
    *       https://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.mybatis.generator.internal.db;
  
  /**
   * Typesafe enum of known database dialects.
   *
   * @author Jeff Butler
   */
  public enum DatabaseDialects {
  
      DB2("VALUES IDENTITY_VAL_LOCAL()"), //$NON-NLS-1$
      MYSQL("SELECT LAST_INSERT_ID()"), //$NON-NLS-1$
      SQLSERVER("SELECT SCOPE_IDENTITY()"), //$NON-NLS-1$
      CLOUDSCAPE("VALUES IDENTITY_VAL_LOCAL()"), //$NON-NLS-1$
      DERBY("VALUES IDENTITY_VAL_LOCAL()"), //$NON-NLS-1$
      HSQLDB("CALL IDENTITY()"), //$NON-NLS-1$
      SYBASE("SELECT @@IDENTITY"), //$NON-NLS-1$
      DB2_MF("SELECT IDENTITY_VAL_LOCAL() FROM SYSIBM.SYSDUMMY1"), //$NON-NLS-1$
      INFORMIX("select dbinfo('sqlca.sqlerrd1') from systables where tabid=1"); //$NON-NLS-1$
  
      private final String identityRetrievalStatement;
  
      DatabaseDialects(String identityRetrievalStatement) {
          this.identityRetrievalStatement = identityRetrievalStatement;
      }
  
      public String getIdentityRetrievalStatement() {
          return identityRetrievalStatement;
      }
  
      /**
       * Gets the database dialect.
       *
       * @param database
       *            the database
       *
       * @return the database dialect for the selected database. May return null if there is no known dialect for the
       *         selected db
       */
      public static DatabaseDialects getDatabaseDialect(String database) {
          DatabaseDialects returnValue = null;
  
          if ("DB2".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = DB2;
          } else if ("MySQL".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = MYSQL;
          } else if ("SqlServer".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = SQLSERVER;
          } else if ("Cloudscape".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = CLOUDSCAPE;
          } else if ("Derby".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = DERBY;
          } else if ("HSQLDB".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = HSQLDB;
          } else if ("SYBASE".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = SYBASE;
          } else if ("DB2_MF".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = DB2_MF;
          } else if ("Informix".equalsIgnoreCase(database)) { //$NON-NLS-1$
              returnValue = INFORMIX;
          }
  
          return returnValue;
      }
  }