package pyUML.backend;

import java.util.Vector;

import org.eclipse.core.resources.IProject;
import org.eclipse.jface.dialogs.Dialog;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.List;
import org.eclipse.swt.widgets.Shell;

/**
 * This is a SWT dialog the lets the user choose one of
 * the given projects.
 * By the next run, the lately selected project in preselected  
 */
public class ChooseProjectDialog extends Dialog{
	public static IProject preSelectedProject = null; 
	
	private java.util.List<IProject> projects;
	private List selectProjectBox;
	private IProject selectedProject = null;
	private java.util.List<String> projectsList;
	
	public ChooseProjectDialog(Shell parent, java.util.List<IProject> projects) {
		super(parent);
		this.projects = projects;
	}
	
	/**
	 * Initializes a ChooseProjectDialog and lets the user choose
	 * one of the given projects.
	 * After "Use" or "Cancel" is pressed, the selected
	 * Project is returned, or null if cancel was pressed. 
	 * @param parent
	 * @param projects
	 * @return
	 */
	public static IProject runChooseProject(Shell parent, java.util.List<IProject> projects) {
		if (preSelectedProject != null && (! preSelectedProject.isOpen()))
			preSelectedProject = null;
		
		// Create dialog
		ChooseProjectDialog dialog = new ChooseProjectDialog(parent, projects);
		dialog.create();
		
		// Pre-select project that was selected before
		if (ChooseProjectDialog.preSelectedProject != null) {
			String preSelectedProjectName = ChooseProjectDialog.preSelectedProject.getName();
			if (dialog.getProjectsList().contains(preSelectedProjectName)) {
				int index = dialog.getProjectsList().indexOf(preSelectedProjectName);
				dialog.selectProjectBox.setSelection(index);
			}
		}
		
		dialog.open();

		ChooseProjectDialog.preSelectedProject = dialog.selectedProject;
		
		return dialog.selectedProject;
	}
	
	protected Control createDialogArea(Composite parent) {	
		Composite composite = (Composite) super.createDialogArea(parent);
		setShellStyle(SWT.DIALOG_TRIM | SWT.RESIZE | SWT.MAX);	
		createControls(composite);
		//add controls to composite as necessary
		return composite;
		} 
	
	public void createControls	(Composite composite) {
		// create graphical components
		Shell shell = composite.getShell();
		shell.setText("Select Python Project To Use");
		
		Group selectBoxGroup = new Group(composite, SWT.None);
		selectBoxGroup.setText("Please select a project to be used by PyUML:");

		selectBoxGroup.setLayoutData(new GridData(GridData.FILL_BOTH));
		selectBoxGroup.setLayout(new GridLayout(1, true));
		
		this.selectProjectBox = new List( selectBoxGroup, SWT.BORDER|SWT.SINGLE|SWT.V_SCROLL|SWT.H_SCROLL	 );
		selectProjectBox.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));
		
		this.projectsList = new Vector<String>();
		for (IProject project : this.projects) {
			this.selectProjectBox.add(project.getName());
			projectsList.add(project.getName());
		}
		
		selectProjectBox.setSize(300,300);
		
		//buttonGroup.pack();
		selectBoxGroup.pack();
		
		composite.pack();

	}

	public void widgetDefaultSelected(SelectionEvent e) {
		// Not needed in this dialog
	}

	protected void buttonPressed(int buttonId) {
		if (IDialogConstants.OK_ID == buttonId) {
			int selectedIndex = this.selectProjectBox.getSelectionIndex();
			if (selectedIndex < 0)
				return;
 
			this.selectedProject = this.projects.get(selectedIndex);
			this.close();
		} else if (IDialogConstants.CANCEL_ID == buttonId) {
			cancelPressed();
		}
	}

	public java.util.List<String> getProjectsList() {
		return projectsList;
	}
}