/*
 * Code by George Kichukov for SAS 10/27/2002
 * Updated 11/24/02
        - add check login
        - add diferent cases
 * This class is used to Select Requirements to be modified for any of the tables that end with _REQ
 * It gets all paramters (table, operation, specific record ID) and displays
 * all requirement records
 * If operation is ADD it redirects to ModifyReq
 * if the operation is Modify /Delete/View it displays appropriate fields

 * Updated 12/05/02 - add checkDelete() javascript
 */

package admin;
import java.util.*;
import java.io.*;
import java.sql.*;
import javax.servlet.*;
import javax.servlet.http.*;

import utilities.*;

public class Req extends HttpServlet
{
        private String errorTarget = "../admin/index.jsp";

        public void init(ServletConfig config) throws ServletException
        {
                super.init(config);
        }

        public void doGet(HttpServletRequest request,
                          HttpServletResponse response)
                          throws ServletException, IOException
        {

                // If it is a get request forward to doPost()
                doPost(request, response);
        }


        public void doPost(HttpServletRequest request, HttpServletResponse response)
                                throws ServletException, IOException
        {
                //name of the user
                String name="";

                PrintWriter out = response.getWriter();
                response.setContentType("text/html");

                //first thing that every servlet or jsp should do is check if user is logged in
                HttpSession session = request.getSession(false);

                //if not logged in redirect to login
                if(session == null)
                {
                        HTMLUtils.printRedirectPage(out, "You must login to the system prior to viewing this page.", errorTarget);
                        return;
                }

                //else if logged in take the name from the session
                else
                {
                        name=(String)session.getAttribute("user");

                        //if the name is null
                        if(name == null)
                        {
                                HTMLUtils.printRedirectPage(out, "You must login to the system prior to viewing this page.", errorTarget);
                                return;
                        }

                }

                //get parameters
                String table =(String) request.getParameter("table");
                String oper =(String) request.getParameter("oper");
                String id=request.getParameter("id");

		HTMLUtils.printAdminHeader(out);
		
                //display welcome message to the user
                out.println("<p align=left>Welcome " + name + "</p>");

                //if we are adding redirect to ModifyReq
                //send 0 for id
                if(oper.equals("Add"))
                {
                         String target = "/servlet/admin.ModifyReq?id=0&oper=" + oper + "&table=" + table + "&mID=" + id;

                          try
                          {
                                // Forward the request to the target named
                                ServletContext context = getServletContext();
                                RequestDispatcher dispatcher = context.getRequestDispatcher(target);
                                dispatcher.forward(request, response);
                          }

                          catch(ServletException e){System.err.println("ServeltException" + e.getMessage());}
                          catch(IOException e){System.err.println("IOException" + e.getMessage());}
                }

                // oper is Modify/View/Delete
                else
                {
                        try
                        {
                                ResultSet rs=null;

                                if(id!=null)
                                {
                                        //pass only MAJORS for MAJOR_REQ
                                        String table2=table.substring(0,table.length()-4) +"S";
                                        ResultSet rs2 = Retriever.getRecordName(id,table2);
                                        rs2.next();
                                        out.println("<br>" + rs2.getString(1));
                                        rs2.close();
                                        //select only the requirements for the specific major
                                        rs = Retriever.getTableID(table, id);
                                }

                                else
                                {
                                        rs = Retriever.getTable(table);
                                }


                                //get all the fields from the table
                                ResultSetMetaData rsmd = rs.getMetaData();
                                int numberOfColumns = rsmd.getColumnCount();

                                out.println("<br><center>" + table + "</center>");
                              

                                 //set up the table
	                         out.println("<TABLE cellpadding=0 cellspacing=0 border=1 width=700 align=center>");
	                         out.println("<tr height=2><td width=50>&nbsp;</td><td width=170>&nbsp;</td><td width=400>&nbsp;</td><td width=80>&nbsp;</td></tr>");    
                                 
                                 
                                 //loop through all columns to display column headings
                                 out.println("<tr>");
                                 for(int j=1; j<numberOfColumns+1; j++)
                                 {
                                         out.println("<td>" + rsmd.getColumnName(j)+ "</td>");
                                 }
                                out.println("</tr>");

                                int counter=0;

                                //loop through all records
                                while(rs.next())
                                {
                                         out.println("<tr>");
                                        
                                        //loop through all columns
                                        for(int i=1; i<numberOfColumns+1; i++)
                                        {
                                                String columnName=rsmd.getColumnName(i);
						

                                                //if it is the ID
                                                if (columnName.equals("ID"))
                                                {
                                                        //get the primary key
                                                        int pk = rs.getInt("ID");
                                                        out.println("<td>" + (++counter));

                                                         //display it as a hidden field
                                                        out.println("<input type=hidden name=" + columnName + " value= " + rs.getInt(columnName) + "></td>");

                                                }

                                                 //if it ends with ID e.g. MajorID, MinorID
                                                else if ((columnName.substring(columnName.length()-2, columnName.length())).equals("ID"))
                                                {
                                                        //display it as a hidden field
                                                        out.println("<input type=hidden name=" + columnName + " value= " + rs.getInt(columnName) + ">");
                                                }

                                                //if it is a list
                                                else if ((columnName.substring(columnName.length()-4, columnName.length())).equals("List"))
                                                {

                                                         // 1. parse the course list
                                                        String req=RequirementParser.toCourseDisplayString(rs.getString(columnName));
                                                        out.println("<td>" + req + "</td>");

                                                }

                                                //esle display it 
                                                else
                                                {
                                                        out.println("<td>" + rs.getString(columnName) + "</td>");
                                                }

                                        }//end for

                                       if (oper.equals("Modify"))
                                       {
                                                out.println("<td align=right valign=top><a href='admin.ModifyReq?id=" + rs.getInt("ID") + "&oper=" + oper + "&table=" + table + "&mID=" + id + "'>Modify</a></td>");
				       }
                                       
                                       else if (oper.equals("Delete"))
                                       {
                                                out.println("<td align=right valign=top><form method=post action=admin.Query onSubmit='return checkDelete()'>");
                                                out.println("<input type=hidden name=table value=" + table + ">");
                                                out.println("<input type=hidden name=oper value=" + oper + ">");
                                                out.println("<input type=hidden name=id value=" + rs.getInt("ID") + ">");
                                                out.println("<input type=submit value=Delete >");
                                                out.println("</form></td>");
                                       }
                                       
                                       else
                                       {
                                       		out.println("<td>&nbsp;</td>");
                                       	}

                                       out.println("</tr>");

                                }//end while

                               
                                rs.close();

                        }//end try

                        catch(SQLException e){out.println("SQLException " + e.getMessage());}

                }//end else

		 HTMLUtils.printAdminFooter(out);

        }//end method

}//end Req.java servlet