/*
 * Created on Mar 24, 2005
 *
 * TODO To change the template for this generated file go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
package org.eclipse.jst.j2ee.navigator.internal.workingsets;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Set;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceChangeEvent;
import org.eclipse.core.resources.IResourceChangeListener;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.runtime.IAdaptable;
import org.eclipse.jem.util.logger.proxy.Logger;
import org.eclipse.jst.j2ee.internal.project.J2EEProjectUtilities;
import org.eclipse.ui.IWorkingSet;
import org.eclipse.ui.IWorkingSetUpdater;
import org.eclipse.wst.common.componentcore.internal.StructureEdit;

/**
 * @author Admin
 *
 * TODO To change the template for this generated type comment go to
 * Window - Preferences - Java - Code Style - Code Templates
 */
public class ComponentWorkingSetUpdater implements IWorkingSetUpdater,
		IResourceChangeListener/*, IResourceDeltaVisitor*/ {
	
	public static final String ID= "org.eclipse.jst.j2ee.navigator.ui.ComponentWorkingSetPage"; //$NON-NLS-1$
	
	private List fWorkingSets;
	
	private HashMap projectStructureEdits;

	private static class WorkingSetDelta {
		private IWorkingSet fWorkingSet;
		private List fElements;
		private boolean fChanged;
		public WorkingSetDelta(IWorkingSet workingSet) {
			fWorkingSet= workingSet;
			fElements= new ArrayList(Arrays.asList(workingSet.getElements()));
		}
		
		public IWorkingSet getWorkingSet() {
			return fWorkingSet;
		}
		
		public int indexOf(Object element) {
			return fElements.indexOf(element);
		}
		
		public void add( Object element) {
			synchronized (fWorkingSet) {
				if (indexOf(element) ==-1) {
					fElements.add(element);
					fChanged= true;
				}
			}
		}
		public void remove(int index) {
			if (fElements.remove(index) != null) {
				fChanged= true;
			}
		}
		public void process() {
			if (fChanged) {
				fWorkingSet.setElements((IAdaptable[])fElements.toArray(new IAdaptable[fElements.size()]));
			}
		}
	 }
	
	/**
	 * 
	 */
	public ComponentWorkingSetUpdater() {
		super();
		fWorkingSets= new ArrayList();
		ResourcesPlugin.getWorkspace().addResourceChangeListener(this);
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkingSetUpdater#add(org.eclipse.ui.IWorkingSet)
	 */
	public void add(IWorkingSet workingSet) {
		//checkElementExistence(workingSet);
		synchronized (fWorkingSets) {
			
			updateElements(workingSet);
			fWorkingSets.add(workingSet);
		}

	}
	

	/**
	 * @param project
	 * @param typeId
	 * @return
	 */
	private boolean containsModuleType(IProject project, String typeId) {
		boolean bReturn = false;
		if (project.isAccessible()) {
			synchronized (this) {
				return J2EEProjectUtilities.isProjectOfType(project,typeId);
			}
		}
		return bReturn;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkingSetUpdater#remove(org.eclipse.ui.IWorkingSet)
	 */
	public boolean remove(IWorkingSet workingSet) {
		boolean result;
		synchronized(fWorkingSets) {
			result= fWorkingSets.remove(workingSet);
		}
		return result;
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkingSetUpdater#contains(org.eclipse.ui.IWorkingSet)
	 */
	public boolean contains(IWorkingSet workingSet) {
		synchronized(fWorkingSets) {
			return fWorkingSets.contains(workingSet);
		}
	}

	/* (non-Javadoc)
	 * @see org.eclipse.ui.IWorkingSetUpdater#dispose()
	 */
	public void dispose() {
		synchronized(fWorkingSets) {
			fWorkingSets.clear();
		}
		disposeStructureEdits();
		ResourcesPlugin.getWorkspace().removeResourceChangeListener(this);
	}

	
	
	
	/* (non-Javadoc)
	 * @see org.eclipse.core.resources.IResourceChangeListener#resourceChanged(org.eclipse.core.resources.IResourceChangeEvent)
	 */
	public void resourceChanged(IResourceChangeEvent event) {
	
 	    IResourceDelta delta= event.getDelta();
 	    if (delta == null) return;
		IResourceDelta[] affectedChildren= delta.getAffectedChildren(IResourceDelta.ADDED | IResourceDelta.REMOVED | IResourceDelta.CHANGED, IResource.PROJECT);
		if (affectedChildren.length > 0) {
			for (int i= 0; i < affectedChildren.length; i++) {
				IResourceDelta projectDelta= affectedChildren[i];
				IProject project = (IProject)projectDelta.getResource();
			
				IWorkingSet[] workingSets;
				synchronized(fWorkingSets) {
					workingSets= (IWorkingSet[])fWorkingSets.toArray(new IWorkingSet[fWorkingSets.size()]);
				}
				for (int w= 0; w < workingSets.length; w++) {
					WorkingSetDelta workingSetDelta= new WorkingSetDelta(workingSets[w]);
					processResourceDelta(workingSetDelta,projectDelta, project);
					workingSetDelta.process();
				}
			}
		}
	}

	
	
	
	private void processResourceDelta(WorkingSetDelta result, IResourceDelta aDelta, IProject aProject) {
		//IResource resource= aDelta.getResource();
		
		int index= result.indexOf(aProject);
		int kind= aDelta.getKind();
		int flags= aDelta.getFlags();
		
		
		switch (aDelta.getKind()) {
		case IResourceDelta.REMOVED :
				 if (index != -1) {
				 	result.remove(index) ;
				 }
				 disposeStructureEdits(aProject);
				 break;
		case IResourceDelta.ADDED : {
				 ComponentWorkingSet workingSet = (ComponentWorkingSet) result.getWorkingSet();
				 if (containsModuleType(aProject,workingSet.getTypeId())) {
				 	if (index == -1)
				 		result.add(aProject);
				 }
				 break;
		}
		
		
		case IResourceDelta.CHANGED :
			// boolean natureMayHaveChanged = ((aDelta.getFlags() & IResourceDelta.DESCRIPTION) != 0) && ((aDelta.getFlags() & IResourceDelta.MARKERS) == 0);
			boolean projectOpenStateChanged = ((aDelta.getFlags() & IResourceDelta.OPEN) != 0);
			if (/*natureMayHaveChanged ||*/ projectOpenStateChanged) {
				if (aProject.isOpen()) {
					ComponentWorkingSet workingSet = (ComponentWorkingSet) result.getWorkingSet();
					 if (containsModuleType(aProject,workingSet.getTypeId())) {
						result.add(aProject);
					 }
				} else {
					if (index != -1) {
					 	result.remove(index) ;
					 }
					disposeStructureEdits(aProject);
				}

			} else {
				 ComponentWorkingSet workingSet = (ComponentWorkingSet) result.getWorkingSet();
				 if (containsModuleType(aProject,workingSet.getTypeId())) {
				 	if (index == -1)
				 		result.add(aProject);
					} else {
				 	if (index != -1) {
				 		result.remove(index) ;
				 	}
				 }
				 break;	
			}
			break;
		}

	}
	
	
	private void updateElements(IWorkingSet workingSet) {
		if (workingSet instanceof ComponentWorkingSet) {
			ComponentWorkingSet componentWorkingSet = (ComponentWorkingSet) workingSet;
			List result= new ArrayList();
			IProject[] projects = ResourcesPlugin.getWorkspace().getRoot().getProjects();
			for (int i= 0; i < projects.length; i++) {
				try {
					if (containsModuleType(projects[i],componentWorkingSet.getTypeId())) {
						result.add(projects[i]);
					}
				} catch (Exception ex) {
					Logger.getLogger().logError(ex);
				}
			}
			componentWorkingSet.setElements((IAdaptable[])result.toArray(new IAdaptable[result.size()]));
		}
	}

	
	 private void disposeStructureEdits() {
			Set keys = getProjectStructureEdits().keySet();
			for (Iterator iter = keys.iterator(); iter.hasNext();) {
				IProject proj = (IProject) iter.next();
				StructureEdit se =(StructureEdit)getProjectStructureEdits().get(proj);
				if (se != null)
					se.dispose();
				
			}
	}
		
	private void disposeStructureEdits(IProject aProject) {
		StructureEdit se =(StructureEdit)getProjectStructureEdits().get(aProject);
		if (se != null)
			se.dispose();
		getProjectStructureEdits().remove(aProject);
	}
	
	private HashMap getProjectStructureEdits() {
		if (projectStructureEdits != null) 
			return projectStructureEdits;
		 
		synchronized(this) {
		   if (projectStructureEdits == null)
			 projectStructureEdits = new HashMap();
		}
		return projectStructureEdits;
		
	}
	
	public StructureEdit getStructureEdit(IProject aProject) {
		if (getProjectStructureEdits().get(aProject) == null)
			getProjectStructureEdits().put(aProject,StructureEdit.getStructureEditForRead(aProject));
		return (StructureEdit)getProjectStructureEdits().get(aProject);
	}

}