package org.kuali.db;
   
   import java.io.File;
   import java.io.FileInputStream;
   import java.io.IOException;
   import java.io.InputStream;
   import java.io.InputStreamReader;
   import java.io.Reader;
   import java.io.StringReader;
  
  import org.springframework.core.io.DefaultResourceLoader;
  import org.springframework.core.io.Resource;
  import org.springframework.core.io.ResourceLoader;
  import static org.apache.commons.lang.StringUtils.*;
  
  /**
   * Contains the definition of a new transaction element. Transactions allow several files or blocks of statements to be
   * executed using the same JDBC connection and commit operation in between.
   */
  public class Transaction {
  	String resourceLocation;
  	String sqlCommand;
  	String encoding;
  	String description;
  
  	/**
       *
       */
  	public void addText(String sql) {
  		if (sqlCommand == null) {
  			sqlCommand = sql;
  		} else {
  			sqlCommand += sql;
  		}
  	}
  
  	public Reader getReader() throws IOException {
  		// The SQL for this transaction is contained in a String
  		if (!isEmpty(sqlCommand)) {
  			return new StringReader(sqlCommand);
  		}
  
  		// If both sqlCommand and resourceLocation are blank, we can't continue
  		if (isEmpty(resourceLocation)) {
  			throw new IOException("Unable to locate the SQL for this transaction");
  		}
  
  		// First check the file system
  		File file = new File(resourceLocation);
  		if (file.exists()) {
  			return getReader(new FileInputStream(file));
  		}
  
  		// Next check Resource locations
  		ResourceLoader loader = new DefaultResourceLoader();
  		Resource resource = loader.getResource(resourceLocation);
  		if (!resource.exists()) {
  			throw new IOException("Unable to locate the SQL for this transaction");
  		}
  		return getReader(resource.getInputStream());
  	}
  
  	protected Reader getReader(InputStream in) throws IOException {
  		if (isEmpty(getEncoding())) {
  			return new InputStreamReader(in);
  		} else {
  			return new InputStreamReader(in, getEncoding());
  		}
  	}
  
  	public String getResourceLocation() {
  		return resourceLocation;
  	}
  
  	public void setResourceLocation(String resourceLocation) {
  		this.resourceLocation = resourceLocation;
  	}
  
  	public String getSqlCommand() {
  		return sqlCommand;
  	}
  
  	public void setSqlCommand(String sqlCommand) {
  		this.sqlCommand = sqlCommand;
  	}
  
  	public String getEncoding() {
  		return encoding;
  	}
  
  	public void setEncoding(String encoding) {
  		this.encoding = encoding;
  	}
  
  	public String getDescription() {
  		return description;
  	}
  
  	public void setDescription(String description) {
 		this.description = description;
 	}
 }