package gui;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.MenuItem;
import org.eclipse.swt.widgets.Monitor;
import org.eclipse.swt.widgets.Shell;

public abstract class GuiManager {
	static Shell mainShell;
	static Composite contentComposite;
	static Display display;


	/**
	 * Add a new composite with content to the main Shell
	 * @param The composite to add, should be a GUI
	 */
	public static void addContent( Composite contentComposite ){
		removeContent();

		GuiManager.contentComposite = contentComposite;

		// sets the starting preferred size.
		GridData gridData = new GridData(GridData.FILL, GridData.FILL, true, true);
		gridData.widthHint = 800;
		gridData.heightHint = 600;
		contentComposite.setLayoutData(gridData);

		mainShell.layout();

	}

	/**
	 * Remove the current content of the main shell
	 */
	private static void removeContent() {
		if(contentComposite != null) {
			GuiManager.contentComposite.dispose();

		}
	}


	public static Display getDisplay(){
		return display; 
	}

	public static void initGui() {
		display = new Display();
		mainShell = new Shell(display, SWT.SHELL_TRIM | SWT.CENTER);

		Menu menuBar = new Menu(mainShell, SWT.BAR);
		MenuItem cascadeFileMenu = new MenuItem(menuBar, SWT.CASCADE);
		cascadeFileMenu.setText("&File");

		Menu fileMenu = new Menu(mainShell, SWT.DROP_DOWN);
		cascadeFileMenu.setMenu(fileMenu);

		MenuItem exitItem = new MenuItem(fileMenu, SWT.PUSH);
		exitItem.setText("&Exit");
		exitItem.addSelectionListener(new SelectionAdapter() {
			@Override
			public void widgetSelected(SelectionEvent e) {
				mainShell.getDisplay().dispose();
				System.exit(0);
			}
		});

		mainShell.setText("Dozmod");
		mainShell.setMenuBar(menuBar);
		
		// Set layout for the mainshell, items added to the shell should get a gridData
		mainShell.setLayout(new GridLayout(1, true));

		addContent(new gui.core.LoginComposite(mainShell));


		// center the window on the primary monitor
		Monitor primary = display.getPrimaryMonitor();
		Rectangle bounds = primary.getBounds();
		Rectangle rect = mainShell.getBounds();

		int x = bounds.x + (bounds.width - rect.width) / 2;
		int y = bounds.y + (bounds.height - rect.height) / 2;

		mainShell.setLocation(x, y);

		mainShell.pack();
		mainShell.open();


		while (!mainShell.isDisposed()) {
			if (!display.readAndDispatch())
				display.sleep();
		}
	}
}