1 files changed, 273 insertions, 0 deletions
diff --git a/dozentenmodul/src/main/java/util/GuiManager.java b/dozentenmodul/src/main/java/util/GuiManager.java
new file mode 100644
index 00000000..a2c4cd1f
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+++ b/dozentenmodul/src/main/java/util/GuiManager.java
@@ -0,0 +1,273 @@
+package util;
+
+import gui.intro.About_GUI;
+import gui.intro.Login_GUI;
+
+import java.awt.BorderLayout;
+import java.awt.Component;
+import java.awt.GraphicsConfiguration;
+import java.awt.GraphicsDevice;
+import java.awt.GraphicsEnvironment;
+import java.awt.HeadlessException;
+import java.awt.Rectangle;
+import java.awt.Window;
+import java.awt.event.ActionEvent;
+import java.awt.event.ActionListener;
+import java.awt.event.MouseAdapter;
+import java.awt.event.MouseEvent;
+
+import javax.swing.JFrame;
+import javax.swing.JInternalFrame;
+import javax.swing.JMenu;
+import javax.swing.JMenuBar;
+import javax.swing.JMenuItem;
+import javax.swing.JOptionPane;
+import javax.swing.plaf.basic.BasicInternalFrameUI;
+
+import org.apache.log4j.Logger;
+
+/**
+ * An abstract class to organize the GUI.
+ * Currently only provide a method for centering Window-objects.
+ */
+public abstract class GuiManager {
+
+	private final static Logger LOGGER = Logger.getLogger(GuiManager.class);
+	
+	/**
+	 * The rectangle representing the bounds of the primary display
+	 */
+	private static Rectangle rect = null;
+
+	/**
+	 * Gets the bounds of the primary display using
+	 * AWT's GraphicsEnvironment class.
+	 */
+	private static boolean getDisplayBounds() {
+		GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
+		GraphicsDevice gd = null;
+		try {
+			gd = ge.getDefaultScreenDevice();
+		} catch (HeadlessException he) {
+			he.printStackTrace();
+			JOptionPane.showMessageDialog(null, "Konnte kein Display ermittelt werden.",
+					"Fehler", JOptionPane.ERROR_MESSAGE);
+			return false;
+		}
+
+		GraphicsConfiguration gc = gd.getDefaultConfiguration();
+		rect = gc.getBounds();
+
+		if (rect == null) {
+			JOptionPane.showMessageDialog(null, "Konnte die Resolution des Bildschirms nicht ermitteln!",
+					"Fehler", JOptionPane.ERROR_MESSAGE);
+			return false;
+		} else {
+			return true;
+		}
+	}
+
+	/**
+	 * Centers the given Window within the bounds of the display
+	 * @param gui The Window object to be centered.
+	 */
+	public static void centerGUI(Window gui) {
+
+		if (rect == null) getDisplayBounds();
+		double width = rect.getWidth();
+		double height = rect.getHeight();
+		double xCenter = (width / 2 - gui.getWidth() / 2);
+		double yCenter = (height / 2 - gui.getHeight() / 2);
+		gui.setLocation((int) xCenter, (int) yCenter);
+	}
+	
+	private static JFrame mainWindow = null;
+	public static JFrame getMainWindow() {
+		return mainWindow;
+	}
+	private static JInternalFrame currentFrame = null;
+	// TODO use this formerFrame when going "back" in the gui
+	private static JInternalFrame formerFrame = null;
+
+	/**
+	 * Starts the GUI by creating the main window
+	 * and showing the Login_GUI as the first frame.
+	 */
+	public static void initGui() {
+		// get the screen size
+		getDisplayBounds();
+		if (rect == null) {
+			LOGGER.error("Could not get display size. Contact developper.");
+			System.exit(1);
+		}
+
+		// create main window
+		mainWindow = new JFrame("DozMod");
+		mainWindow.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
+		mainWindow.setResizable(false);
+		
+		// create login frame
+		currentFrame = new Login_GUI();
+		mainWindow.getContentPane().add(currentFrame, BorderLayout.CENTER);
+		((BasicInternalFrameUI)currentFrame.getUI()).setNorthPane(null);
+		mainWindow.pack();
+
+		// size management
+		mainWindow.setBounds(0, 0, 785, 430);
+		mainWindow.setLocation((int) (rect.getWidth() / 2 - mainWindow.getWidth() / 2),
+				(int) (rect.getHeight() / 2 - mainWindow.getHeight() / 2));
+		
+		// finally let's see the frames
+		currentFrame.setVisible(true);
+		mainWindow.setVisible(true);
+	}
+
+	/**
+	 * Private function to add the menu bar to the main window.
+	 * @return true if adding the menu bar worked, false otherwise
+	 */
+	private static boolean addMenuBar() {
+		JMenuBar menuBar = new JMenuBar();
+		mainWindow.setJMenuBar(menuBar);
+
+		JMenu helpMenu = new JMenu("Hilfe");
+		menuBar.add(helpMenu);
+
+		// FAQ Field
+		JMenuItem mntmFaq = new JMenuItem("FAQ");
+		mntmFaq.addMouseListener(new MouseAdapter() {
+			@Override
+			public void mousePressed(MouseEvent arg0) {
+				OpenLinks.openWebpage("faq");
+			}
+		});
+		helpMenu.add(mntmFaq);
+		// OTRS Field
+		JMenuItem mntmOtrs = new JMenuItem("OTRS");
+		mntmOtrs.addMouseListener(new MouseAdapter() {
+			@Override
+			public void mousePressed(MouseEvent arg0) {
+					OpenLinks.openWebpage("otrs");
+			}
+		});
+		helpMenu.add(mntmOtrs);
+		// About Field
+		JMenuItem mntmAbout = new JMenuItem("About");
+		mntmAbout.addActionListener(new ActionListener() {
+			public void actionPerformed(ActionEvent arg0) {
+				GuiManager.openPopup(new About_GUI());
+			}
+		});
+		helpMenu.add(mntmAbout);
+		return true;
+	}
+	/**
+	 * Private function to determine whether the currentFrame has a
+	 * 'HELP_MESSAGE' defined and to add it to the menu bar if found one.
+	 * @return true if setting the help button to the menu bar worked, false otherwise
+	 */
+	private static boolean addHelp() {
+		// let's see if we have a HELP_MESSAGE variable defined in
+		// the class of the currentFrame, if so we need to show it by pressing "Hilfe"
+		String test = "";
+		try {
+			test = (String) (currentFrame.getClass().getDeclaredField("HELP_MESSAGE").get(currentFrame));
+		} catch (NoSuchFieldException e) {
+			// only this case if interesting for us, 
+			// since we now we don't have a help message to show
+			LOGGER.debug("No 'HELP_MESSAGE' defined in class: " + currentFrame.getClass().getName());
+			return true;
+		} catch (IllegalArgumentException|IllegalAccessException|SecurityException e) {
+			LOGGER.error("Failed to check for 'HELP_MESSAGE' variable in '"
+					+ currentFrame.getClass() + "' class, see trace: " + e);
+			// just do nothing
+		}
+		// print it for debugging purposes
+		LOGGER.debug("HELP_MESSAGE of '" + currentFrame.getClass().getName() + "': " + test);
+		// still here? means we have a HELP_MESSAGE to display
+		JMenu mnNewMenu_Info = new JMenu("Info");
+		mnNewMenu_Info.addMouseListener(new MouseAdapter() {
+			@Override
+			public void mousePressed(MouseEvent arg0) {
+				String helpMessage = null;
+				try {
+					helpMessage = (String) currentFrame.getClass().getField("HELP_MESSAGE").get(currentFrame);
+				} catch (IllegalArgumentException | IllegalAccessException
+						| NoSuchFieldException | SecurityException e) {
+					LOGGER.error("Failed to check for 'HELP_MESSAGE' variable in '"
+							+ currentFrame.getClass() + "' class, see trace: " + e);
+				}
+				JOptionPane.showMessageDialog(currentFrame, helpMessage != null ? helpMessage : "No help message.",
+						"Hilfe zu dieser Oberfläche", JOptionPane.INFORMATION_MESSAGE);
+			}
+		});
+		mainWindow.getJMenuBar().add(mnNewMenu_Info);
+		return true;
+	}
+
+	/**
+	 * Public function to show the given frame, replacing the current frame
+	 * @param newFrame the new frame to show
+	 */
+	public static void show(JInternalFrame newFrame) {
+		// first remove the current component
+		currentFrame.setVisible(false);
+		mainWindow.getContentPane().remove(currentFrame);
+		// save it as formerFrame in case we need it
+		formerFrame = currentFrame;
+		// from now on currentFrame is newFrame !!!
+		currentFrame = newFrame;
+		currentFrame.setBorder(null);
+
+		// show the menu bar for everything but the Login_GUI
+		if (!(currentFrame instanceof Login_GUI)) {
+			if (mainWindow.getMenuBar() == null) {
+				if (!addMenuBar()) {
+					LOGGER.error("Failed to add menu to main window. See logs.");
+				}
+			}
+			// add help if needed
+			if (!addHelp()) {
+				LOGGER.error("Failed to add help to main window's menu. See logs.");
+			}
+		}
+		// prepare the switch
+		if (currentFrame.getUI() instanceof BasicInternalFrameUI) {
+			BasicInternalFrameUI bar = ((BasicInternalFrameUI) currentFrame.getUI());
+			if (bar.getNorthPane() != null) bar.setNorthPane(null);
+		}
+		// TODO else case
+		
+		mainWindow.setTitle(newFrame.getTitle() != null ? newFrame.getTitle() : "bwLehrpool Suite");
+		mainWindow.getContentPane().add(currentFrame, BorderLayout.CENTER);
+		mainWindow.setBounds((int)mainWindow.getLocationOnScreen().getX(), (int)mainWindow.getLocationOnScreen().getY(),
+				currentFrame.getWidth(), currentFrame.getHeight());
+		currentFrame.setVisible(true);
+		
+	}
+	/**
+	 * Public function to show the given frame, replacing the current frame
+	 * @param newFrame the new frame to show
+	 * @param center true if the main window is to be centered, false otherwise
+	 */
+	public static void show(JInternalFrame newFrame, boolean center) {
+		show(newFrame);
+		if (center) {
+			double xCenter = (rect.getWidth() / 2 - newFrame.getWidth() / 2);
+			double yCenter = (rect.getHeight() / 2 - newFrame.getHeight() / 2);
+			mainWindow.setBounds((int) xCenter, (int) yCenter,
+					newFrame.getWidth(), newFrame.getHeight());
+		}
+	}
+	/**
+	 * 
+	 */
+	public static void openPopup(Component popup) {
+		if (!(popup instanceof JFrame)) {
+			LOGGER.error("Popup classes need to be JFrame, given a: " + popup.getClass().getName());
+			return;
+		}
+		((JFrame)popup).setLocation((int)(rect.getWidth() / 2 - popup.getWidth() / 2), (int)(rect.getHeight() / 2 - popup.getHeight() / 2));
+		((JFrame)popup).setVisible(true);
+	}
+}