package org.drools.eclipse.debug;



import java.io.ObjectInputStream;

import java.io.StringReader;

import java.util.List;



import org.drools.eclipse.DroolsEclipsePlugin;

import org.eclipse.debug.core.DebugException;

import org.eclipse.debug.core.model.IValue;

import org.eclipse.debug.core.model.IVariable;

import org.eclipse.debug.ui.IDebugUIConstants;

import org.eclipse.jdt.debug.core.IJavaObject;

import org.eclipse.jface.action.IToolBarManager;

import org.eclipse.jface.viewers.ISelection;

import org.eclipse.jface.viewers.IStructuredSelection;

import org.eclipse.jface.viewers.Viewer;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.ui.ISelectionListener;

import org.eclipse.ui.IWorkbenchPart;



import com.thoughtworks.xstream.XStream;



/**

 * An audit view that shows the contents of the selected logger when debugging.

 * 

 * @author <a href="mailto:kris_verlaenen@hotmail.com">Kris Verlaenen</a>

 */

public class RealtimeAuditView extends AuditView implements ISelectionListener {



    public void dispose() {

        getSite().getPage().removeSelectionListener(IDebugUIConstants.ID_VARIABLE_VIEW, this);

        super.dispose();

    }



    protected Viewer createViewer(Composite parent) {

        getSite().getPage().addSelectionListener(IDebugUIConstants.ID_VARIABLE_VIEW, this);

    	return super.createViewer(parent);

    }

    

    protected void setViewerInput(Object context) {

     	// if an in memory logger has been explicitly selected as variable

    	if (context instanceof IVariable) {

        	IVariable variable = (IVariable) context;

            try {

                IValue value = ((IVariable) context).getValue();

                if (value != null && value instanceof IJavaObject

                        && "org.drools.audit.WorkingMemoryInMemoryLogger".equals(

                            variable.getValue().getReferenceTypeName())) {

                	setAuditEvents((IJavaObject) value);

                }

            } catch (Throwable t) {

                DroolsEclipsePlugin.log(t);

            }

        }

    }



	protected void becomesHidden() {

		setViewerInput(null);

		super.becomesHidden();

	}



	protected void becomesVisible() {

		super.becomesVisible();

        ISelection selection = getSite().getPage().getSelection(

            IDebugUIConstants.ID_VARIABLE_VIEW);

        if (selection instanceof IStructuredSelection) {

            setViewerInput(((IStructuredSelection) selection).getFirstElement());

        }

    }



    public void selectionChanged(IWorkbenchPart part, ISelection selection) {

        if (!isAvailable()) {

            return;

        }

        if (selection == null) {

            setViewerInput(null);

        } else if (selection instanceof IStructuredSelection) {

            setViewerInput(((IStructuredSelection) selection).getFirstElement());

        }

    }

    

	protected void createActions() {

	}

	

    protected void configureToolBar(IToolBarManager tbm) {

    }

    

    private void setAuditEvents(IJavaObject inMemoryLogger) throws DebugException {

        IValue eventString = DebugUtil.getValueByExpression("return getEvents();", inMemoryLogger);

        String s = eventString.getValueString();

        if (s != null) {

        	try {

				XStream xstream = new XStream();

				ObjectInputStream in = xstream.createObjectInputStream(

					new StringReader(s));

				getViewer().setInput(createEventList((List) in.readObject()));

        	} catch (Throwable t) {

        		DroolsEclipsePlugin.log(t);

        		getViewer().setInput(null);

        	}

        } else {

        	getViewer().setInput(null);

        }

    }

}