import java.io.*;
import java.sql.*;
import java.util.*;
import javax.swing.*;

public class DBDriver
{
    private static Connection conn = null;
    private String dbname;
    private Vector sqlArray = new Vector();

    //Asks User to inputThe name of the Table and the Name of the Database
    public DBDriver()
    {
        while(dbname == null)
        {
            dbname = JOptionPane.showInputDialog("Enter Name of Database including Extension","mazegenerator.mdb");
                }
                connect();
                //disconnect();
        }
        public DBDriver(String db)
    {
        dbname = db;
    }
    //-------------------------------------------------------------------------------------
    //Opens A Connection to the Database
    private void connect ()
    {
        try
        {
            Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");
        }
        catch (ClassNotFoundException c)
        {
            System.out.println ("Unable to load database driver!!!!");
        }

        try
        {

            String database = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=";
            database += dbname.trim () + ";DriverID=22;READONLY=true}"; // add on to the end
                    String asd = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb)};DBQ=C:\\Users\\pr-hamhut\\Desktop\\MazeGenerator\\mazegenerator.mdb;DriverID=22;READONLY=true}";
            conn = DriverManager.getConnection (asd, "", "");
        }
        catch (Exception e)
        {
            System.out.println ("Unable to connect to database \n" + e);
        }
    }
    //Closes the Connection to the Database
    private void disconnect ()
    {
        try
        {
            conn.close ();
        }
        catch (SQLException se)
        {
            System.out.println ("An sql error occured");
        }
    }
    //Requests data From The Database Returns in  a String
    public String requestQ(String sql)
    {
        String r = "";
        try
        {
            connect();
            Statement s = conn.createStatement();
            ResultSet rs = s.executeQuery(sql);
            ResultSetMetaData rsmd = rs.getMetaData();
            int numberOfColumns = rsmd.getColumnCount();
            while(rs.next())
            {
                for(int i = 1; i <= numberOfColumns; i++)
                {
                    r += rs.getString(rsmd.getColumnName(i));
                        }
                        r += "\n";
                }
            rs.close();
            s.close();
            addSql(sql);
        }
        catch(SQLException se)
        {
            addSql("Error: " + sql);
            System.out.println("Error in RequestQ() Method \n" + sql);
        }
        disconnect();
        return r;
    }
    //Updates Data In the Database, Void return type
    public void updateQ(String sql)
    {
        connect();
        try
        {
            Statement s = conn.createStatement();
            s.executeUpdate(sql);
            s.close();
            addSql(sql);
                System.out.println("Update Complete");
        }
        catch(SQLException se)
        {
            addSql("Error: " + sql);
            System.out.println("Error in UpdateQ() Exception \n" + sql);
        }
        disconnect();
    }
    //Returns the Column Headings of the Specified Table(Can be changed in setTable() method)
    public String getColumnHeadings(String tbl)
    {
        connect();
        String r = "";
        try
        {
            Statement s = conn.createStatement();
            ResultSet rs = s.executeQuery("Select * FROM " + tbl);
            ResultSetMetaData rsmd = rs.getMetaData();
            int numOfColumns = rsmd.getColumnCount();

            for(int i = 1; i <= numOfColumns; i++)
            {
                r += addSpaces(15,rsmd.getColumnName(i) + "");
            }
            addSql("Select * FROM " + tbl);
        }
        catch(SQLException se)
        {
            addSql("Error: " + "Select * FROM " + tbl);
            System.out.println("Error in getColumnHeadings() method \n Most Likely Database Doesn't Exist or Wrong tblName");
        }
        disconnect();
        return r;
    }
    //takes the first line of a multiple lined string and returns it
    public String toOne(String s)
    {
        String arr[] = s.split("\n");
        return arr[0];
    }
    //----------------------------------------------------------------------------------------
    //adds the Latest sql Statement put througth the object into a Vector Array
    public void addSql(String sql)
    {
        sqlArray.add(sql);
    }
    //prints from the last 'num' positions of the array
    public String getSql()
    {
    return (sqlArray.lastElement() + "");
    }
    //returns the array of sql statements
    public String getSql(int num)
    {
        String r = "";
        try
        {
            for(int i = sqlArray.size() - num; i < sqlArray.size(); i++)
            {
                r += i + "\t" + sqlArray.get(i) + "\n";
            }
        }
        catch(Exception oobe)
        {
            System.out.println("num, out of bounds");
        }
        if(r.equals(""))
        {
            r = sqlArray.get(sqlArray.size()) + "";
        }
        return r;
    }
    //adds spaces to a String, makes all strings equal length for an even print. Returns String
    public String addSpaces(int num, String s)
    {
        String r = s;
        for(int i = s.length(); i < num; i++)
        {
            r += " ";
        }
        return r;
    }
    //reads a file
    public String[] File(String filename)
    {
        String r = "";
        try
        {
            Scanner sc = new Scanner(new File(filename));
            while (sc.hasNextLine())
            {
                r += sc.nextLine() + "\n";
            }
            sc.close();
        }
        catch(FileNotFoundException fne)
        {
            System.out.println("File Not Found \n" + filename);
        }
        String[] ret = r.split("\n");
        return ret;
    }
    //appends to a specified file
    public void AppendFile(String filename, String input)
    {
        try
        {
            FileWriter out = new FileWriter(new File(filename));
            BufferedWriter writer = new BufferedWriter(out);
            writer.write("\r\n" + input);
            writer.close();
        }
        catch(Exception e)
        {
            System.out.println("File not appended");

        }
    }
}