/*
    *  
    *  Fosstrak LLRP Commander (www.fosstrak.org)
    * 
    *  Copyright (C) 2008 ETH Zurich
    *
    *  This program is free software: you can redistribute it and/or modify
    *  it under the terms of the GNU General Public License as published by
    *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program.  If not, see <http://www.gnu.org/licenses/> 
   *
   */
  
  package org.fosstrak.llrp.commander.dialogs;
  
  import java.rmi.RemoteException;
  import java.util.ArrayList;
  import java.util.HashMap;
  import java.util.HashSet;
  import java.util.Iterator;
  import java.util.Map;
  import java.util.Set;
  
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.events.SelectionAdapter;
  import org.eclipse.swt.events.SelectionEvent;
  import org.eclipse.swt.graphics.Color;
  import org.eclipse.swt.graphics.Point;
  import org.eclipse.swt.graphics.Rectangle;
  import org.eclipse.swt.layout.GridData;
  import org.eclipse.swt.layout.GridLayout;
  import org.eclipse.swt.widgets.Button;
  import org.eclipse.swt.widgets.Composite;
  import org.eclipse.swt.widgets.Control;
  import org.eclipse.swt.widgets.Event;
  import org.eclipse.swt.widgets.Label;
  import org.eclipse.swt.widgets.List;
  import org.eclipse.swt.widgets.Listener;
  import org.eclipse.swt.widgets.ProgressBar;
  import org.eclipse.swt.widgets.Shell;
  import org.eclipse.swt.widgets.Table;
  import org.eclipse.swt.widgets.TableColumn;
  import org.eclipse.swt.widgets.TableItem;
  import org.eclipse.swt.widgets.Text;
  import org.fosstrak.llrp.adaptor.Adaptor;
  import org.fosstrak.llrp.adaptor.AdaptorManagement;
  import org.fosstrak.llrp.adaptor.exception.LLRPRuntimeException;
  import org.fosstrak.llrp.commander.ResourceCenter;
  import org.llrp.ltk.types.LLRPMessage;
  
  /**
   * This Dialog will be triggered by the context menu from <code>LLRPEditor</code>
   * User pick up the readers to issue the LLRP messages.
   *
   * @author Haoning Zhang
   * @author sawielan
   * @version 1.0
   */
  public class SendMessageDialog extends org.eclipse.jface.dialogs.Dialog {
  	
  	// the previously selected readers
  	private Map<String, Set<String> > previouslySelected = 
  		new HashMap<String, Set<String> > ();
  	
  	private ProgressBar progressBar;
  	
  	private List outputList;
  	
  	private Table tblReaders;
  	
  	private Text txtComment;
  	
  	private static SendMessageDialog instance;
  	
  	/**
  	 * Default Constructor
  	 * 
  	 * @param aShell
  	 */
  	private SendMessageDialog(Shell aShell) {
  		super(aShell);
  	}
  	
  	public static SendMessageDialog getInstance(Shell aShell) {
  		if (null == instance) {
  			instance = new SendMessageDialog(aShell);
  		} 
  
  		return instance;
  	}
  	
 
 	/**
 	 * Initialize the GUI components.
 	 */
 	protected Control createContents(Composite parent) {
 		
 		String fileName = ResourceCenter.getInstance().getCurrentFileName();
 		
 		parent.getShell().setLayout(new GridLayout(2, false));
 		parent.getShell().setText("Sending " + fileName);
 		
 		GridData gridText = new GridData(GridData.FILL_HORIZONTAL);
 		gridText.horizontalSpan = 2;
 		gridText.heightHint = 15;
 		gridText.widthHint = 400;
 		
 		GridData gridList = new GridData(GridData.FILL_HORIZONTAL);
 		gridList.horizontalSpan = 2;
 		gridList.heightHint = 180;
 		
 		GridData gridComment = new GridData(GridData.FILL_HORIZONTAL);
 		gridComment.horizontalSpan = 2;
 		gridComment.heightHint = 18;
 		
 		GridData gridOutput = new GridData(GridData.FILL_HORIZONTAL);
 		gridOutput.horizontalSpan = 2;
 		gridOutput.heightHint = 100;
 		
 		GridData gridBar = new GridData(GridData.FILL_HORIZONTAL);
 		gridBar.horizontalSpan = 2;
 		gridBar.heightHint = 15;
 		
 		GridData gridButton = new GridData(GridData.FILL_BOTH);
 		gridButton.horizontalSpan = 1;
 		gridButton.heightHint = 25;
 		
 		Rectangle shellBounds = parent.getShell().getShell().getBounds();
         Point dialogSize = parent.getShell().getSize();
 
         this.getShell().setLocation(shellBounds.x + (shellBounds.width - dialogSize.x) / 2,
           shellBounds.y + (shellBounds.height - dialogSize.y) / 2);
         
         
         final Label lblReaders = new Label(parent, SWT.NONE);
         lblReaders.setLayoutData(gridText);
         lblReaders.setText("Select Readers:");
         
         tblReaders = new Table (parent, SWT.BORDER | SWT.MULTI | SWT.V_SCROLL | SWT.FULL_SELECTION);
 		tblReaders.setLayoutData(gridList);
 		tblReaders.setBounds (0, 0, 300, 200);
 		tblReaders.setLinesVisible (true);
 		tblReaders.setHeaderVisible (true);
 		
 		TableColumn columnAdapter = new TableColumn (tblReaders, SWT.NONE);
 		columnAdapter.setText ("Adapter");
 		TableColumn columnReader = new TableColumn (tblReaders, SWT.NONE);
 		columnReader.setText ("Reader");
 
 		try {
 			Iterator<String> i = AdaptorManagement.getInstance().getAdaptorNames().iterator();
 			while (i.hasNext()) {
 				Adaptor adaptor = AdaptorManagement.getInstance().getAdaptor(i.next());
 
 				Iterator<String> j = adaptor.getReaderNames().iterator();
 				while (j.hasNext()) {
 					String readerName = j.next();
 					if (adaptor.getReader(readerName).isConnected()) {
 						
 						TableItem item = new TableItem (tblReaders, 0);
 						String adapter = adaptor.getAdaptorName();
 						item.setText(0, adapter);
 						item.setText(1, readerName);
 					}
 				}
 			}
 		} catch (LLRPRuntimeException llrpe) {
 			llrpe.printStackTrace();
 		} catch (RemoteException re) {
 			re.printStackTrace();
 		}
 		
 		// for all the currently available readers, check if they have been
 		// selected during the last send action.
 		ArrayList<Integer> selected = new ArrayList<Integer> ();
 		// check, if we need to preselect it
 		for (int i=0; i<tblReaders.getItemCount(); i++) {
 			TableItem item = tblReaders.getItem(i);
 			if (wasSelected(item.getText(0), item.getText(1))) {
 				selected.add(i);
 			}
 		}
 		previouslySelected = new HashMap<String, Set<String>> ();
 		
 		columnAdapter.pack();
 		columnReader.pack();
 		
 		if (selected.size() > 0) {
 			int [] selectionArray = new int[selected.size()];
 			for (int i=0; i<selectionArray.length; i++) {
 				selectionArray[i] = selected.get(i);
 			}
 			tblReaders.setSelection(selectionArray);
 		}
 		
 		final Label lblComment = new Label(parent, SWT.NONE);
 		lblComment.setLayoutData(gridText);
 		lblComment.setText("Comment:");
 		
 		txtComment = new Text(parent, SWT.BORDER);
 		txtComment.setTextLimit(16);
 		txtComment.setLayoutData(gridComment);
 		
 		final Label lblOutput = new Label(parent, SWT.NONE);
 		lblOutput.setLayoutData(gridText);
 		lblOutput.setText("Progress:");
         
 		outputList = new List(parent, SWT.BORDER | SWT.MULTI | SWT.V_SCROLL);
         outputList.setLayoutData(gridOutput);
         outputList.setBackground(new Color(parent.getDisplay(), 255, 255, 255));
         outputList.setForeground(new Color(parent.getDisplay(), 0, 0, 0));
         
 		progressBar = new ProgressBar (parent, SWT.SMOOTH);
 		progressBar.setLayoutData(gridBar);
 		progressBar.setMinimum(0);
 		progressBar.setMaximum(100);
 		progressBar.setSelection(0);
 
 		
 		final Button btnOK = new Button(parent, SWT.PUSH);
 		btnOK.setText("Send");
 		btnOK.setLayoutData(gridButton);
 		btnOK.addSelectionListener(new SelectionAdapter() {
 		      public void widgetSelected(SelectionEvent e) {
 		    	  
 		    	  btnOK.setEnabled(false);
 		    	  outputList.removeAll();
 		    	  
 	    		  if (sendMessage()) {
 	    			  close();
 	    		  }
 	    		  
 		    	  btnOK.setText("Send Again");
 		    	  btnOK.setEnabled(true);
 		      }
 		    });
 		
 		
 		final Button btnCancel = new Button(parent, SWT.PUSH);
 		btnCancel.setText("Close");
 		btnCancel.setLayoutData(gridButton);
 		btnCancel.addSelectionListener(new SelectionAdapter() {
 		      public void widgetSelected(SelectionEvent e) {
 		    	  close();
 		      }
 		    });
 		
 		if (tblReaders.getSelectionIndices().length == 0) {
 			btnOK.setEnabled(false);
 			btnCancel.setFocus();
 		} else {
 			btnOK.setEnabled(true);
 			btnOK.setFocus();
 		}
 		
 		tblReaders.addListener(SWT.Selection, new Listener () {
 			public void handleEvent (Event e) {
 				int[] selectedList = tblReaders.getSelectionIndices();
 				
 				if ((selectedList == null) || (selectedList.length == 0)) {
 					btnOK.setEnabled(false);
 				} else {
 					btnOK.setEnabled(true);
 				}
 			}
 		});
 		
 		tblReaders.addListener(SWT.DefaultSelection, new Listener () {
 			public void handleEvent (Event e) {
 				int[] selectedList = tblReaders.getSelectionIndices();
 				if ((selectedList == null) || (selectedList.length == 0)) {
 					btnOK.setEnabled(false);
 				} else {
 					btnOK.setEnabled(true);
 				}
 			}
 		});
 		
 		parent.pack();
 		return parent;
 		
 	}
 
 	/**
 	 * saves the readers selected in the table-readers to the previously 
 	 * selected data-structure.
 	 * @param tblReaders the table with the readers.
 	 * @param selectedList the readers that are currently selected.
 	 */
 	private void saveSelectedReaders(Table tblReaders,
 			int[] selectedList) {
 		
 		for (int i=0; i<selectedList.length; i++) {
 			TableItem item = tblReaders.getItem(selectedList[i]);
 			add(item.getText(0), item.getText(1));
 		}
 	}
 	
 	/**
 	 * add a reader to the set of a given adapter.
 	 * @param adapter the adapter.
 	 * @param reader the reader.
 	 */
 	private void add(String adapter, String reader) {
 		Set<String> readers = previouslySelected.get(adapter);
 		if (null == readers) {
 			readers = new HashSet<String> ();
 			previouslySelected.put(adapter, readers);
 		}
 		readers.add(reader);
 	}
 	
 	/**
 	 * check if the reader was previously selected.
 	 * @param adapter the name of the adapter.
 	 * @param reader the name of the reader.
 	 * @return true if previously selected, false otherwise.
 	 */
 	private boolean wasSelected(String adapter, String reader) {
 		Set<String> readers = previouslySelected.get(adapter);
 		if (null == readers) return false;
 		
 		return readers.contains(reader);
 	}
 	
 	private void output(String aLine) {
 		if (null != outputList) {
 			outputList.add(aLine);
 		}
 	}
 	
 	private void setProgress(int aPercent) {
 		if (aPercent < 0) {
 			aPercent = 0;
 		}
 		
 		if (aPercent > 100) {
 			aPercent = 100;
 		}
 		
 		if (null != progressBar) {
 			progressBar.setSelection(aPercent);
 		}
 	}
 	
 	private boolean sendMessage() {
 		
 		String fileName = ResourceCenter.getInstance().getCurrentFileName();
 		output("Reading " + fileName + "...");
 		setProgress(10);
 		
 		String xmlContent = ResourceCenter.getInstance().getCurrentFile();
 		
 		if ((null == xmlContent) || (xmlContent.equals(""))) {
 			output("Reading " + fileName + "failed!");
 			return false;
 		} else {
 			output(fileName + " loaded.");
 			setProgress(30);
 		}
 		
 		LLRPMessage message = ResourceCenter.getInstance().generateLLRPMessage(xmlContent);
 		if (null == message) {
 			output("Generate LLRPMessage object failed!");
 			return false;
 		} else {
 			output("LLRPMessage object generated successfully.");
 			setProgress(60);
 		}
 		
 		int step = progressBar.getMaximum() - progressBar.getSelection();
 		
 		int [] selectedList = tblReaders.getSelectionIndices();
 		// save the selected readers for the next send action.
 		saveSelectedReaders(tblReaders, selectedList);
 		if (selectedList.length > 0) {
 			step = step / selectedList.length;
 		}
 		
 		String comment = "";
 		
 		if ((txtComment != null) && (!txtComment.getText().equals(""))) {
 			comment = txtComment.getText();
 		}
 		
 		for (int i = 0; i < selectedList.length; i++) {
 			
 			TableItem item = tblReaders.getItem(selectedList[i]);
 			ResourceCenter.getInstance().sendMessage(item.getText(0),
 					item.getText(1), message, comment);
 			output("Sending to " + item.getText(1) + " @ " + item.getText(0) + "...");
 			setProgress(progressBar.getSelection() + (i + 1) * step);
 		}
 		
 		return true;
 	}
 }