package quickstart;

import java.io.*;
import java.sql.*;
import java.util.*;
import de.mathema.pride.*;

/**
 * Simple command line client to interactively run a few database operations.
 * It demonstrates the most common operations of record creation, update,
 * retrieval and deletion.
 */
public class CustomerClient implements SQLExpression.Operator {
    private String prompt;
    private BufferedReader input;

    public CustomerClient(  String prompt ) {
        this.prompt = prompt;
        try {
          input = new BufferedReader(new InputStreamReader( System.in ) );
        } catch ( Exception uee ) {
          System.out.println( "error: trying to open System.in ..." );
          System.exit(0);
        }
    }

    /** Read-eval-print loop of this interactive client */
    protected void work() throws Exception {
      usage();
      String cmd_ln = null;
      while ( true ) {
        System.out.print( prompt );
        System.out.flush();
        cmd_ln = input.readLine();
        StringTokenizer st = new StringTokenizer( cmd_ln, " ", false );
        int count = st.countTokens();
        String[] str = new String[count];
        for ( int i = 0; i < count; i++ ) {
          str[i] = st.nextToken();
        }
        executeCmd (str);
      }
    }

    /** Databaes record creation */
    private void create(int id, String name, String firstName)
    	throws SQLException {
    	Customer c = new Customer(id, name, firstName);
    	c.create();
    }

    /** Database record update */
    private void update(int id, String name, String firstName)
    	throws SQLException {
    	Customer c = new Customer(id, name, firstName);
    	c.update();
    }

    /**
     * Query by example, using a finder method,
     * which returns only the first matching record
     */
    private void findByID(int id)
    	throws SQLException {
    	Customer c = new Customer(id, null, null);
    	c.find();
    	System.out.println(c.getId() + ": " + c.getName() + "," + c.getFirstname());
    }

    /** Database record deletion */
    private void delete(int id)
    	throws SQLException {
    	Customer c = new Customer(id, null, null);
    	c.delete();
    }

    /**
     * Query by example, using a query method,
     * which returns all matching records in a record iterator
     */
    private void queryByName( String name )
    	throws SQLException {
    	Customer c = new Customer(0, name, null);
    	ResultIterator ri = c.query(new String[] { "name" });
    	do {
    	    System.out.println(c.getId() + ": " + c.getName() + "," + c.getFirstname());
    	} while(ri.next());
    }

    /**
     * More complex query, making use of an SQLExpression
     */
    private void queryByRange( int idLow, int idHigh )
    	throws SQLException {
    	Customer c = new Customer(0, null, null);
    	SQLExpression exp = new SQLExpression(DatabaseFactory.getDatabase());
    	exp = exp.and("id", GREATEREQUAL, idLow).
    	    and("id", LESSEQUAL, idHigh);
    	ResultIterator ri = c.query(exp.toString());
    	do {
    	    System.out.println(c.getId() + ": " + c.getName() + "," + c.getFirstname());
    	} while(ri.next());
    }

    /** Command dispatcher function */
    protected void executeCmd( String[] cmd ) {
      try {
        if ( cmd.length < 1 ) {
            usage();
            return;
        }

        if ( cmd[0].equals( "exit" ) || cmd[0].equals( "quit" )) {
            System.exit( 0 );
        } else if ( cmd[0].equals( "create" ) ) {
            if (cmd.length < 4 ) {
                usage();
                return;
            }
            create( Integer.parseInt(cmd[1]), cmd[2], cmd[3] );
        } else if ( cmd[0].equals( "update" ) ) {
            if (cmd.length < 4 ) {
                usage();
                return;
            }
            update( Integer.parseInt(cmd[1]), cmd[2], cmd[3] );
        } else if ( cmd[0].equals( "findbyid" ) ) {
            if (cmd.length < 2 ) {
                usage();
                return;
            }
            findByID( Integer.parseInt(cmd[1]) );
        } else if ( cmd[0].equals( "delete" ) ) {
            if (cmd.length < 2 ) {
                usage();
                return;
            }
            delete( Integer.parseInt(cmd[1]) );
        } else if ( cmd[0].equals( "querybyname" ) ) {
            if (cmd.length < 2 ) {
                usage();
                return;
            }
            queryByName( cmd[1] );
        } else if ( cmd[0].equals( "querybyrange" ) ) {
            if (cmd.length < 3 ) {
                usage();
                return;
            }
            queryByRange( Integer.parseInt(cmd[1]), Integer.parseInt(cmd[2]) );
        }
    	else
    	    usage();
      }
      catch(Exception x) {
    	  x.printStackTrace();
      }
    }

    public static void main(String[] arg) {
        try {
            Properties props = System.getProperties();

            // Check the configuration properties
            if (props.getProperty(ResourceAccessor.Config.DRIVER) == null)
                throw new Exception("Driver class must be specified by -Dpride.driver=<driver class>");
            if (props.getProperty("pride.db") == null)
                throw new Exception("Database url must be specified by -Dpride.db=<database url>");
            if (props.getProperty(ResourceAccessor.Config.USER) == null)
                System.out.println("Warning: no user name specified by -Dpride.user");
            if (props.getProperty(ResourceAccessor.Config.PASSWORD) == null)
                System.out.println("Warning: no password specified by -Dpride.password");
            if (props.getProperty(ResourceAccessor.Config.DBTYPE) == null)
                System.out.println("Warning: no database type specified by -Dpride.dbtype");
            if (props.getProperty(ResourceAccessor.Config.LOGFILE) == null)
                props.setProperty(ResourceAccessor.Config.LOGFILE, "sql.log");

	        // PriDE initialization
    	    ResourceAccessorJ2SE accessor = new ResourceAccessorJ2SE(props);
    	    DatabaseFactory.setResourceAccessor(accessor);
    	    DatabaseFactory.setDatabaseName(props.getProperty("pride.db"));

            CustomerClient cc = new CustomerClient("customer>");
            cc.work();
        } catch ( Exception ex ) {
            System.out.println(ex.getMessage());
        }
    }

    private void usage() {
    	System.out.println
    	    ("------------------------------------------------------------------------\n" +
    	     "Usage: \n" +
    	     "[exit]                       shutdown the console\n" +
    	     "[create ID name firstname]   create a customer\n" +
    	     "[update ID name firstname]   update a customer\n" +
    	     "[findbyid ID]                find a customer by its ID\n" +
    	     "[querybyname name]           find customers by their name\n" +
    	     "[querybyrange ID ID]         find all customers in the given ID range\n" +
    	     "[delete ID]                  delete a customer\n" +
    	     "------------------------------------------------------------------------\n"
    	     );
    }
    
}