path: root/dozentenmodul/src/main/java/org/openslx/dozmod/gui/window/LectureDetailsWindow.java

package org.openslx.dozmod.gui.window;

import java.awt.Color;
import java.awt.Frame;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.Comparator;
import java.util.Date;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import javax.swing.DefaultComboBoxModel;
import javax.swing.JFrame;
import javax.swing.JOptionPane;
import javax.swing.JRadioButton;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

import org.apache.log4j.Logger;
import org.apache.thrift.TException;
import org.openslx.bwlp.thrift.iface.ImageDetailsRead;
import org.openslx.bwlp.thrift.iface.ImageSummaryRead;
import org.openslx.bwlp.thrift.iface.ImageVersionDetails;
import org.openslx.bwlp.thrift.iface.LecturePermissions;
import org.openslx.bwlp.thrift.iface.LectureRead;
import org.openslx.bwlp.thrift.iface.LectureWrite;
import org.openslx.bwlp.thrift.iface.NetRule;
import org.openslx.bwlp.thrift.iface.NetShare;
import org.openslx.bwlp.thrift.iface.UserInfo;
import org.openslx.dozmod.gui.Gui;
import org.openslx.dozmod.gui.MainWindow;
import org.openslx.dozmod.gui.control.JCheckBoxTree.CheckChangeEvent;
import org.openslx.dozmod.gui.control.JCheckBoxTree.CheckChangeEventListener;
import org.openslx.dozmod.gui.control.LectureCustomPermissionManager.UserChangeEvent;
import org.openslx.dozmod.gui.control.LectureCustomPermissionManager.UserChangeEventListener;
import org.openslx.dozmod.gui.control.NetshareConfigurator.NetshareConfigurationChangeEvent;
import org.openslx.dozmod.gui.control.NetshareConfigurator.NetshareConfigurationChangeEventListener;
import org.openslx.dozmod.gui.control.RunscriptConfigurator.RunscriptConfigurationChangeEvent;
import org.openslx.dozmod.gui.control.RunscriptConfigurator.RunscriptConfigurationChangeEventListener;
import org.openslx.dozmod.gui.helper.DateTimeHelper;
import org.openslx.dozmod.gui.helper.MessageType;
import org.openslx.dozmod.gui.helper.TextChangeListener;
import org.openslx.dozmod.gui.helper.UiFeedback;
import org.openslx.dozmod.gui.window.UserListWindow.UserAddedCallback;
import org.openslx.dozmod.gui.window.layout.LectureDetailsWindowLayout;
import org.openslx.dozmod.permissions.ImagePerms;
import org.openslx.dozmod.permissions.LecturePerms;
import org.openslx.dozmod.thrift.Session;
import org.openslx.dozmod.thrift.ThriftActions;
import org.openslx.dozmod.thrift.ThriftActions.DownloadCallback;
import org.openslx.dozmod.thrift.ThriftActions.LectureMetaCallback;
import org.openslx.dozmod.thrift.ThriftError;
import org.openslx.dozmod.thrift.cache.UserCache;
import org.openslx.dozmod.util.FormatHelper;
import org.openslx.dozmod.util.MapHelper;
import org.openslx.thrifthelper.ThriftManager;

/**
 * Window to display and edit the details of a lecture
 */
@SuppressWarnings("serial")
public class LectureDetailsWindow extends LectureDetailsWindowLayout implements UiFeedback {

	private static final Logger LOGGER = Logger.getLogger(LectureDetailsWindow.class);

	/**
	 * Self-reference
	 */
	private final LectureDetailsWindow me = this;

	/**
	 * Callback interface to refresh lecture list after changing lecture details
	 */
	public interface LectureUpdatedCallback {
		public void updated(boolean success);
	}

	/**
	 * Callback to be called when changing lecture details on the server
	 */
	private LectureUpdatedCallback callback = null;

	/**
	 * Lecture that this window shows the details of
	 */
	private LectureRead lecture = null;

	/**
	 * The custom permissions of the lecture
	 */
	private Map<String, LecturePermissions> customPermissions;

	/**
	 * The original custom permissions as fetched from the server
	 */
	private Map<String, LecturePermissions> originalCustomPermissions;

	/**
	 * The original default permissions as fetched from the server
	 */
	private LecturePermissions originalDefaultPermissions;
	/**
	 * Image, that the lecture is linked to.
	 */
	private ImageDetailsRead image = null;

	/**
	 * Flag indicating a change in this lecture's linked image
	 */
	private boolean imageLinkChanged = false;

	/**
	 * Flag indicating a change in this lecture's metadata
	 */
	private boolean metadataChanged = false;

	/**
	 * Flag indicating a change in this lecture's permissions
	 */
	private boolean permissionsChanged = false;

	/**
	 * Holder of the location information of this lecture
	 */
	private LocationInfo locationInfo = null;

	/**
	 * Holder of the netrules/runscript of this lecture
	 */
	private List<NetRule> currentNetrules = null;
	private List<NetRule> originalNetrules = null;
	private String currentRunscript = null;
	private String originalRunscript = null;
	private List<NetShare> currentNetshares = null;
	private List<NetShare> originalNetshares = null;

 	/**
	 * Constructor
	 * 
	 * @param modalParent parent of this popup window
	 * @param callback function to be called when a lecture update occured
	 */
	public LectureDetailsWindow(Frame modalParent, LectureUpdatedCallback callback) {
		super(modalParent);

		// save callback
		this.callback = callback;

		setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);

		addWindowListener(new WindowAdapter() {
			@Override
			public void windowClosing(WindowEvent e) {
				safeClose();
			}
		});

		btnLinkImage.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				ImageSummaryRead newImage = LectureChangeImage.open(me);
				if (newImage != null) {
					try {
						image = ThriftManager.getSatClient().getImageDetails(Session.getSatelliteToken(),
								newImage.imageBaseId);
					} catch (TException e1) {
						LOGGER.error("Failed to retrieve details of new image: ", e1);
						return;
					}
					lecture.imageBaseId = newImage.imageBaseId;
					lecture.imageVersionId = newImage.latestVersionId;
					fillVersionsCombo();
					cboVersions.setEnabled(false);
					chkAutoUpdate.setSelected(true);
					imageLinkChanged = true;
					txtImageName.setText(newImage.getImageName());
					reactToChange();
				}
			}
		});

		btnClose.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				safeClose();
			}
		});
		btnDownloadImage.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				performImageDownload();
			}
		});
		chkAutoUpdate.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				cboVersions.setEnabled(!chkAutoUpdate.isSelected());
			}
		});
		btnChangeOwner.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				UserListWindow.open(me, new UserAddedCallback() {
					@Override
					public void userAdded(UserInfo user, UserListWindow window) {
						window.dispose();
						if (Gui.showMessageBox(me, "Sind Sie sicher, dass sie die Besitzerrechte an "
								+ "einen anderen Account übertragen wollen?", MessageType.QUESTION_YESNO,
								LOGGER, null))
							setLectureOwner(user);
					}
				}, "Besitzer festlegen", lecture.ownerId);
			}
		});

		final ActionListener changeReacter = new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				reactToChange();
			}
		};
		
		ctlLocationSelector.getTree().addCheckChangeEventListener(new CheckChangeEventListener() {
			@Override
			public void checkStateChanged(CheckChangeEvent event) {
				reactToChange();
			}
		});
		for (JRadioButton btn : ctlLocationSelector.getButtons()) {
			btn.addActionListener(changeReacter);
		}
		final ActionListener updateDefaultPermissionListener = new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				ctlPermissionManager.updateDefaultPermissions(chkCustomPermAdmin.isSelected(),
						chkCustomPermEdit.isSelected());
				reactToChange();
			}
		};
		chkCustomPermAdmin.addActionListener(updateDefaultPermissionListener);
		chkCustomPermEdit.addActionListener(updateDefaultPermissionListener);
		ctlPermissionManager.getTable().addMouseListener(new MouseAdapter() {
			@Override
			public void mouseClicked(MouseEvent e) {
				reactToChange();
			}
		});
		ctlPermissionManager.addUserChangeEventListener(new UserChangeEventListener() {			
			@Override
			public void stateChanged(UserChangeEvent event) {
				reactToChange();
			}
		});
		chkCustomPermAdmin.addActionListener(changeReacter);
		chkCustomPermEdit.addActionListener(changeReacter);

		btnNetrules.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				List<NetRule> newNetrules = LectureNetrulesWindow.open(me, currentNetrules);
				if (newNetrules != null)
					currentNetrules = newNetrules;
				reactToChange();
			}
		});

		final TextChangeListener docListener = new TextChangeListener() {
			@Override
			public void changed() {
				reactToChange();
			}
		};

		txtTitle.getDocument().addDocumentListener(docListener);
		txtDescription.getDocument().addDocumentListener(docListener);
		ctlRunscriptConfigurator.addRunscriptConfigurationChangeEventListener(new RunscriptConfigurationChangeEventListener() {
			@Override
			public void stateChanged(RunscriptConfigurationChangeEvent event) {
				reactToChange();
			}

		});
		ctlNetshareConfigurator.addNetshareConfigurationChangeEventListener(new NetshareConfigurationChangeEventListener() {
			@Override
			public void stateChanged(NetshareConfigurationChangeEvent event) {
				reactToChange();
			}
		});
		// Comboboxes
		final ItemListener comboItemListener = new ItemListener() {
			@Override
			public void itemStateChanged(ItemEvent e) {
				if (e.getStateChange() == ItemEvent.SELECTED) {
					reactToChange();
				}
			}
		};
		cboVersions.addItemListener(comboItemListener);

		// Listener to detect changes in checkboxes
		final ActionListener actionListener = new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				reactToChange();
			}
		};
		ChangeListener changeListener = new ChangeListener() {
			@Override
			public void stateChanged(ChangeEvent e) {
				reactToChange();
			}
		};
		chkAutoUpdate.addActionListener(actionListener);
		chkIsExam.addActionListener(actionListener);
		chkHasInternetAccess.addActionListener(actionListener);
		chkHasUsbAccess.addActionListener(actionListener);
		chkIsActive.addActionListener(actionListener);
		dtpStartDate.addActionListener(actionListener);
		dtpEndDate.addActionListener(actionListener);
		spnStartTime.addChangeListener(changeListener);
		spnEndTime.addChangeListener(changeListener);

		// save default color of date/time stuff to reset the background later
		dateTimeTextColor = dtpStartDate.getForeground();
		// last step, the save button
		btnSaveChanges.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				saveChanges();
			}
		});
		// disable save button
		btnSaveChanges.setEnabled(false);
		// wait for the image to be loaded before (potentially) enabling fields
		toggleEditable(false);
	}

	/**
	 * Sets the lecture to show the details of by setting the 'lecture' and
	 * 'image'
	 * members to its metadata. This method will fetch the information from the
	 * sat
	 * 
	 * @param lectureId the id of the lecture to be displayed
	 */
	public void setLecture(final String lectureId) {
		ThriftActions.getLectureAndImageDetails(JOptionPane.getFrameForComponent(me), lectureId,
				new LectureMetaCallback() {
					@Override
					public void fetchedLectureAndImageDetails(LectureRead lectureDetails,
							ImageDetailsRead imageDetails) {
						synchronized (me) {
							lecture = lectureDetails;
							image = imageDetails;
							if (lecture != null) {
								customPermissions = ThriftActions.getLecturePermissions(
										JOptionPane.getFrameForComponent(me), lecture.lectureId);
							}
							fillDetails();
						}
					}
				});
	}

	/**
	 * Internal callback function when we received the lecture's details from the server
	 */
	private void fillDetails() {
		if (lecture == null) {
			txtTitle.setText("-");
			lblTitleInfo.setText("-");
			toggleEditable(false);
			return;
		}

		if (image == null) {
			txtImageName.setText("-");
			lblImageNameInfo.setText("-");
		} else {
			txtImageName.setText(image.getImageName());
			lblImageNameInfo.setText(image.getImageName());
		}

		// remember original netrules and runscript
		originalNetrules = lecture.networkExceptions != null ? lecture.networkExceptions : new ArrayList<NetRule>();
		originalRunscript = lecture.runscript != null ? lecture.runscript : new String("");
		originalNetshares = lecture.networkShares != null ? new ArrayList<NetShare>(lecture.networkShares) : new ArrayList<NetShare>();

		currentNetrules = originalNetrules;
		currentRunscript = originalRunscript;
		currentNetshares = originalNetshares;


		// remember default permissions
		if (lecture.defaultPermissions != null) {
			originalDefaultPermissions = new LecturePermissions(lecture.defaultPermissions);
		}
		// remember custom permissions
		if (customPermissions != null) {
			// need a deep copy of the permission map to be able to check for changes after ImageCustomPermissionWindow
			if (originalCustomPermissions == null)
				originalCustomPermissions = new HashMap<String, LecturePermissions>();
			else
				originalCustomPermissions.clear();
			// fill it
			for (Entry<String, LecturePermissions> entry : customPermissions.entrySet()) {
				originalCustomPermissions.put(entry.getKey(), new LecturePermissions(entry.getValue()));
			}
		}
		// init permission info
		ctlPermissionManager.initPanel(customPermissions, lecture.defaultPermissions, lecture.ownerId);
		chkCustomPermAdmin.setSelected(lecture.defaultPermissions.admin);
		chkCustomPermEdit.setSelected(lecture.defaultPermissions.edit);
		// init location info
		locationInfo = new LocationInfo(lecture.locationIds, lecture.limitToLocations);
		ctlLocationSelector.setOnlyInSelection(locationInfo.limitToLocations);
		ctlLocationSelector.setSelectedLocationsAsIds(locationInfo.locationList);

		// init advanced info
		ctlRunscriptConfigurator.setState(lecture.runscript);
		ctlNetshareConfigurator.setState(lecture.networkShares);

		txtTitle.setText(lecture.getLectureName());
		lblTitleInfo.setText(lecture.getLectureName());
		txtDescription.setText(lecture.getDescription());
		lblOwner.setUser(UserCache.find(lecture.getOwnerId()));
		lblOwnerInfo.setUser(UserCache.find(lecture.getOwnerId()));
		lblUpdater.setUser(UserCache.find(lecture.getUpdaterId()));
		lblCreateTime.setText(FormatHelper.longDate(lecture.getCreateTime()));
		lblUpdateTime.setText(FormatHelper.longDate(lecture.getUpdateTime()));
		lblStartTime.setText(FormatHelper.longDate(lecture.getStartTime()));
		lblEndTime.setText(FormatHelper.longDate(lecture.getEndTime()));
		txtId.setText(lecture.getLectureId());

		chkIsActive.setSelected(lecture.isEnabled);
		chkHasInternetAccess.setSelected(lecture.hasInternetAccess);
		chkHasUsbAccess.setSelected(lecture.hasUsbAccess);
		chkIsExam.setSelected(lecture.isExam);
		chkAutoUpdate.setSelected(lecture.autoUpdate);
		cboVersions.setEnabled(!lecture.autoUpdate);

		lblUseCount.setText(Integer.toString(lecture.useCount));
		fillVersionsCombo();

		Calendar startCal = Calendar.getInstance();
		startCal.setTime(new Date(lecture.getStartTime() * 1000l));
		dtpStartDate.getModel().setDate(startCal.get(Calendar.YEAR), startCal.get(Calendar.MONTH),
				startCal.get(Calendar.DATE));
		spnStartTime.getModel().setValue(startCal.getTime());

		Calendar endCal = Calendar.getInstance();
		endCal.setTime(new Date(lecture.getEndTime() * 1000l));
		dtpEndDate.getModel().setDate(endCal.get(Calendar.YEAR), endCal.get(Calendar.MONTH),
				endCal.get(Calendar.DATE));
		spnEndTime.getModel().setValue(endCal.getTime());

		// now enable the tabs the user can see given its permissions
		toggleEditable(true);
		// and always switch to the "About" tab
		pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Übersicht"));
		setVisible(true);
	}

	/**
	 * Helper to fill the combobox with the versions of the image. The list will
	 * be sorted by creation timestamp
	 */
	private void fillVersionsCombo() {
		List<ImageVersionDetails> versions;
		if (image == null) {
			versions = new ArrayList<>(0);
		} else {
			versions = image.getVersions();
		}
		// version combo
		for (Iterator<ImageVersionDetails> it = versions.iterator(); it.hasNext();) {
			ImageVersionDetails version = it.next();
			if (!version.isValid && !lecture.imageVersionId.equals(version.versionId)) {
				it.remove();
			}
		}

		// sort versions by createtime
		Collections.sort(versions, new Comparator<ImageVersionDetails>() {
			public int compare(ImageVersionDetails o1, ImageVersionDetails o2) {
				return -Long.compare(o1.getCreateTime(), o2.getCreateTime());
			}
		});

		cboVersions.setModel(new DefaultComboBoxModel<ImageVersionDetails>(
				versions.toArray(new ImageVersionDetails[versions.size()])));
		cboVersions.setSelectedItem(new ImageVersionDetails(lecture.getImageVersionId(), 0, 0, 0, null, true,
				true, true, null));
	}

	/**
	 * Sets the lecture's owner to the given user
	 * 
	 * @param user UserInfo representation of the new owner
	 */
	private void setLectureOwner(final UserInfo user) {
		if (!ThriftActions.setLectureOwner(JOptionPane.getFrameForComponent(this), lecture.getLectureId(),
				user)) {
			return;
		}
		// success
		Gui.showMessageBox(me, "Besitzrechte übertragen an " + FormatHelper.userName(user), MessageType.INFO,
				null, null);
		toggleEditable(false);
		String lectureId = lecture.getLectureId();
		synchronized (me) {
			image = null;
			lecture = null;
		}
		setLecture(lectureId);
	}

	/**
	 * Triggers the download of the currently used image version of the lecture
	 */
	private void performImageDownload() {
		if (image == null) {
			Gui.showMessageBox(this, "VM ungültig.", MessageType.ERROR, null, null);
			return;
		}
		btnDownloadImage.setEnabled(false);
		long versionSize = 0;
		for (ImageVersionDetails version : image.versions) {
			if (version.versionId.equals(lecture.imageVersionId)) {
				if (!version.isValid) {
					Gui.showMessageBox(this, "Ungültige VM-Version gewählt", MessageType.ERROR, null, null);
					return;
				}
				versionSize = version.fileSize;
				break;
			}
		}
		if (versionSize == 0) {
			Gui.showMessageBox(this, "Fehler bei der Abfrage der Größe des VM-Abbildes.", MessageType.ERROR, null,
					null);
			return;
		}
		ThriftActions.initDownload(JOptionPane.getFrameForComponent(this), lecture.imageVersionId,
				image.imageName, image.virtId, image.osId, versionSize, new DownloadCallback() {
					@Override
					public void downloadInitialized(boolean success) {
						if (!success) {
							Gui.asyncExec(new Runnable() {
								@Override
								public void run() {
									btnDownloadImage.setEnabled(true);
								}
							});
						}
					}
				});
	}

	/**
	 * Checks whether the user changed any fields of the image details and
	 * enables the save button if so.
	 */
	private void reactToChange() {
		// before checks we need to update the local objects holding the information of the "widgets"
		// update the location information
		locationInfo = new LocationInfo(ctlLocationSelector.getSelectedLocationsAsIds(),
				ctlLocationSelector.getOnlyInSelection());
		// update the custom permissions
		customPermissions = ctlPermissionManager.updatePermissionReferences();
		// NOTE: AdvancedConfiguration stuff will only get checked when clicking "Save" since
		// checking for rules syntax while the user is still typing does not make much sense...
		// now we can check for changes
		metadataChanged = reactToChangeInternal();
		permissionsChanged = MapHelper.hasChanged(originalCustomPermissions, customPermissions);
		btnSaveChanges.setEnabled(metadataChanged || permissionsChanged);
	}

	/**
	 * Checks whether the user changed any fields of the image details and
	 * enables the save button if so.
	 */
	private boolean reactToChangeInternal() {
		if (lecture == null)
			return false;

		boolean changed = false;
		// mandatory fields checks
		if (txtTitle.getText().isEmpty()) {
			pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Allgemein"));
			lblError.setText("Kein Veranstaltungsname gesetzt!");
			return false;
		}
		if (txtDescription.getText().isEmpty()) {
			pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Allgemein"));
			lblError.setText("Keine Beschreibung angegeben!");
			return false;
		}
		// version checkbox changed?
		ImageVersionDetails currentVersion = cboVersions.getItemAt(cboVersions.getSelectedIndex());
		if (currentVersion == null) {
			pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Allgemein"));
			lblError.setText("Keine Version ausgewählt!");
			return false;
		}
		// Date stuff
		Date start = DateTimeHelper.getDateFrom(dtpStartDate, spnStartTime);
		Date end = DateTimeHelper.getDateFrom(dtpEndDate, spnEndTime);
		if (!isPeriodValid(start, end, false) && dateHasChanged()) {
			pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Allgemein"));
			lblError.setText("Ungültiger Zeitraum!");
			return false;
		}
		// runscript stuff
		String newState = ctlRunscriptConfigurator.getState();
		if (newState == null) {
			// script extension was missing from the user input.
			// feedback happens in the configurator, just switch to the tab.
			pnlTabs.setSelectedIndex(pnlTabs.indexOfTab("Startskript"));
			return false;
		} else {
			currentRunscript = newState;
		}

		// netshare stuff
		List<NetShare> newNetshareList = ctlNetshareConfigurator.getState();
		if (newNetshareList != null) {
			currentNetshares = newNetshareList;
		}
		// done with mandatory checks, remove error message
		lblError.setText(null);

		// check for changes in all fields
		changed = !txtTitle.getText().equals(lecture.getLectureName())
				|| !txtDescription.getText().equals(lecture.getDescription())
				|| !currentVersion.getVersionId().equals(lecture.getImageVersionId())
				|| (DateTimeHelper.getDateFrom(dtpStartDate, spnStartTime).getTime() / 1000L) != lecture.getStartTime()
				|| (DateTimeHelper.getDateFrom(dtpEndDate, spnEndTime).getTime() / 1000L) != lecture.getEndTime()
				|| chkAutoUpdate.isSelected() != lecture.autoUpdate
				|| chkIsExam.isSelected() != lecture.isExam
				|| chkHasInternetAccess.isSelected() != lecture.hasInternetAccess
				|| chkHasUsbAccess.isSelected() != lecture.hasUsbAccess
				|| chkIsActive.isSelected() != lecture.isEnabled
				|| !lecture.defaultPermissions.equals(originalDefaultPermissions)
				|| (locationInfo != null && lecture.locationIds != null && !lecture.locationIds.equals(locationInfo.locationList))
				|| (locationInfo != null && lecture.limitToLocations != locationInfo.limitToLocations)
				|| (currentNetrules != null && !currentNetrules.equals(originalNetrules))
				|| (currentRunscript != null && !currentRunscript.equals(originalRunscript))
				|| (currentNetshares != null && !currentNetshares.equals(originalNetshares))
				|| imageLinkChanged;
		return changed;
	}

	/**
	 * Triggers the saving of the changes of this lecture
	 * And inform the callback function about the outcome
	 */
	private void saveChanges() {
		boolean saved = saveChangesInternal();
		callback.updated(saved);
		if (saved)
			dispose();
		else
			btnSaveChanges.setEnabled(true);
	}

	/**
	 * Internal helper actually saving the changes to the satellite
	 *
	 * @return true if saving succeeded, false otherwise.
	 */
	private boolean saveChangesInternal() {
		// check, whether autoupdate is selected and choose version accordingly
		if (image != null) {
			lecture.imageVersionId = chkAutoUpdate.isSelected() ? image.latestVersionId
					: cboVersions.getItemAt(cboVersions.getSelectedIndex()).versionId;
		}

		metadataChanged |= (currentNetrules != lecture.networkExceptions
				|| currentRunscript != lecture.runscript
				|| currentNetshares != lecture.networkShares);
		// now check if we need to push a new LectureWrite
		if (metadataChanged) {
			// first build the LectureWrite from the GUI fields
			final LectureWrite metadata = new LectureWrite(txtTitle.getText(), txtDescription.getText(),
					lecture.getImageVersionId(), chkAutoUpdate.isSelected(), chkIsActive.isSelected(),
					DateTimeHelper.getDateFrom(dtpStartDate, spnStartTime).getTime() / 1000L,
					DateTimeHelper.getDateFrom(dtpEndDate, spnEndTime).getTime() / 1000L, currentRunscript, null,
					chkIsExam.isSelected(), chkHasInternetAccess.isSelected(), // TODO USBACCESS
					lecture.getDefaultPermissions(), locationInfo.locationList, locationInfo.limitToLocations,
					// TODO: coming "false" is Location related
					false, chkHasUsbAccess.isSelected());
			metadata.setNetworkExceptions(currentNetrules);
			metadata.setNetworkShares(currentNetshares);

			// now trigger the actual action 
			try {
				ThriftManager.getSatClient().updateLecture(Session.getSatelliteToken(),
						lecture.getLectureId(), metadata);
				metadataChanged = false;
				LOGGER.info("Successfully save new metadata");
			} catch (TException e) {
				ThriftError.showMessage(JOptionPane.getFrameForComponent(this), LOGGER, e,
						"Fehler beim Updaten der Veranstaltung!");
				callback.updated(false);
				return false;
			}
		}
		if (permissionsChanged) {
			try {
				ThriftManager.getSatClient().writeLecturePermissions(Session.getSatelliteToken(),
						lecture.lectureId, customPermissions);
				permissionsChanged = false;
				LOGGER.info("Successfully save new permissions");
			} catch (TException e) {
				ThriftError.showMessage(JOptionPane.getFrameForComponent(this), LOGGER, e,
						"Fehler beim Übertragen der Berechtigungen!");
				callback.updated(true);
				return false;
			}
		}
		return true;
	}

	/**
	 * Checks if the given start and end date represent a valid time period.
	 * This is the case, if start < end and if current time < end
	 * 
	 * @param start date of the period to check
	 * @param end date of the period to check
	 * @param feedback true if the user should be shown feedback, false
	 *            otherwise
	 * @return true if the period is valid, false otherwise
	 */
	private boolean isPeriodValid(final Date start, final Date end, boolean feedback) {
		if (start == null || end == null)
			return false;
		// analyse time stuff to see if its valid
		if (start.after(end)) {
			dtpStartDate.setForeground(Color.red);
			if (feedback)
				Gui.showMessageBox(me, "Start der Veranstaltung ist nach dem Enddatum!", MessageType.ERROR,
						LOGGER, null);
		} else {
			dtpStartDate.setForeground(dateTimeTextColor);
			return true;
		}
		return false;
	}

	/**
	 * Check whether the date has been changed
	 * 
	 * @return true if it has changed, false otherwise
	 */
	private boolean dateHasChanged() {
		return (DateTimeHelper.getDateFrom(dtpStartDate, spnStartTime).getTime() / 1000L) != lecture.getStartTime()
				|| (DateTimeHelper.getDateFrom(dtpEndDate, spnEndTime).getTime() / 1000L) != lecture.getEndTime();
	}

	/**
	 * Enables/Disables the tabs based on the given flag 'editable'.
	 *
	 * @param editable when true, will enable the tabs if the user is allowed to see them.
	 * If false, this will disable all tabs but the first tab "About".
	 */
	protected void toggleEditable(boolean editable) {
		// if we don't have a lecture and an image set, just disable
		editable &= (LecturePerms.canEdit(lecture));
		// enable the standard tabs that are always enabled
		pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Allgemein"), editable);
		pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Berechtigungen"), editable && LecturePerms.canAdmin(lecture));
		// enable the other tabs that might have been added to the panel (depends on API version)
		if (pnlTabs.indexOfTab("Beschränkungen") != -1) {
			pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Beschränkungen"), editable);
		}
		if (pnlTabs.indexOfTab("Raumauswahl") != -1) {
			pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Raumauswahl"), editable);
		}
		if (pnlTabs.indexOfTab("Startskript") != -1) {
			pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Startskript"), editable);
		}
		if (pnlTabs.indexOfTab("Netzlaufwerke") != -1) {
			pnlTabs.setEnabledAt(pnlTabs.indexOfTab("Netzlaufwerke"), true);
		}
		btnChangeOwner.setEnabled(LecturePerms.canAdmin(lecture));
		btnDownloadImage.setEnabled(ImagePerms.canDownload(image));
	}

	/**
	 * Opens a new LectureDetailsWindow showing the details of the
	 * lecture with ID = lectureId
	 * 
	 * @param modalParent parent of this window
	 * @param lectureId id of the lecture to set the details of
	 */
	public static void open(Frame modalParent, String lectureId, LectureUpdatedCallback callback) {
		LectureDetailsWindow win = new LectureDetailsWindow(modalParent, callback);
		win.setLecture(lectureId);
		win.setVisible(true);
	}

	@SuppressWarnings("deprecation")
	@Override
	public void show() {
		if (!isVisible()) {
			pack();
			MainWindow.centerShell(this);
		}
		super.show();
	}

	/* *******************************************************************************	
	 * 
	 *                        UIFeedback implementation
	 *
	 ********************************************************************************/
	@Override
	public boolean wantConfirmQuit() {
		return metadataChanged || permissionsChanged;
	}

	@Override
	public void escapePressed() {
		// Also ask if applicable
		safeClose();
	}

	/*
	 * Safe close helper: checks if we have unsaved work and prompt the user for
	 * confirmation if so
	 */
	private void safeClose() {
		if ((metadataChanged || permissionsChanged)
				&& !Gui.showMessageBox(me, "Änderungen werden verworfen, wollen Sie wirklich schließen?",
						MessageType.QUESTION_YESNO, null, null))
			return;
		synchronized(me) {
			lecture = null;
			image = null;
		}
		dispose();
	}
}