package guru.mikelue.jdut.jdbc.util;
   
   import java.sql.DatabaseMetaData;
   import java.sql.SQLException;
   
   import org.apache.commons.lang3.StringUtils;
   
   public class MetaDataWorker {
   	private final boolean storesUpperCaseIdentifiers;
  	private final boolean storesLowerCaseIdentifiers;
  	private final boolean storesMixedCaseIdentifiers;
  	private final boolean supportsMixedCaseIdentifiers;
  	private final boolean supportsSchemasInTableDefinitions;
  	private final boolean supportsSchemasInDataManipulation;
  	private final String identifierQuoteString;
  
  	public MetaDataWorker(DatabaseMetaData metaData)
  	{
  		try {
  			/**
  			 * Identifier configurations of database
  			 */
  			storesUpperCaseIdentifiers = metaData.storesUpperCaseIdentifiers();
  			storesLowerCaseIdentifiers = metaData.storesLowerCaseIdentifiers();
  			storesMixedCaseIdentifiers = metaData.storesMixedCaseIdentifiers();
  			supportsMixedCaseIdentifiers = metaData.supportsMixedCaseIdentifiers();
  			// :~)
  
  			/**
  			 * Schema configuration of database
  			 */
  			supportsSchemasInTableDefinitions = metaData.supportsSchemasInTableDefinitions();
  			supportsSchemasInDataManipulation = metaData.supportsSchemasInDataManipulation();
  			// :~)
  
  			String quoteString = metaData.getIdentifierQuoteString();
  			identifierQuoteString = " ".equals(quoteString) ? null : quoteString;
  		} catch (SQLException e) {
  			throw new RuntimeException("Cannot load metadata", e);
  		}
  	}
  
  	public String processIdentifier(String identifier)
  	{
  		identifier = StringUtils.trimToNull(identifier);
  		if (identifier == null) {
  			return null;
  		}
  
  		/**
  		 * Changes the identifier to upper or lower case if the database is case insensitive
  		 */
  		if (storesLowerCaseIdentifiers || storesMixedCaseIdentifiers) {
  			return identifier.toLowerCase();
  		} else if (storesUpperCaseIdentifiers) {
  			return identifier.toUpperCase();
  		}
  		// :~)
  
  		if (!supportsMixedCaseIdentifiers) {
  			identifier.toLowerCase();
  		}
  
  		// Case sensitive
  		return identifier;
  	}
  
  	public String quoteIdentifier(String identifier)
  	{
  		return String.format("%s%s%s", identifierQuoteString, identifier, identifierQuoteString);
  	}
  
  	public boolean supportsSchemasInTableDefinitions()
  	{
  		return supportsSchemasInTableDefinitions;
  	}
  
  	public boolean supportsSchemasInDataManipulation()
  	{
  		return supportsSchemasInDataManipulation;
  	}
  }