/*******************************************************************************
 * Copyright (c) 2000, 2003 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/

package net.sourceforge.phpdt.internal.ui.text;

import net.sourceforge.phpdt.core.ElementChangedEvent;
import net.sourceforge.phpdt.core.IElementChangedListener;
import net.sourceforge.phpdt.core.JavaCore;
import net.sourceforge.phpeclipse.PHPeclipsePlugin;
import net.sourceforge.phpeclipse.phpeditor.PHPUnitEditor;

import org.eclipse.core.resources.IMarkerDelta;
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.IWorkspace;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.reconciler.DirtyRegion;
import org.eclipse.jface.text.reconciler.MonoReconciler;
import org.eclipse.swt.events.ShellAdapter;
import org.eclipse.swt.events.ShellEvent;
import org.eclipse.swt.events.ShellListener;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IFileEditorInput;
import org.eclipse.ui.IPartListener;
import org.eclipse.ui.IWorkbenchPart;
import org.eclipse.ui.IWorkbenchPartSite;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.texteditor.ITextEditor;

/**
 * A reconciler that is also activated on editor activation.
 */
public class JavaReconciler extends MonoReconciler {

	/**
	 * Internal part listener for activating the reconciler.
	 */
	private class PartListener implements IPartListener {

		/*
		 * @see org.eclipse.ui.IPartListener#partActivated(org.eclipse.ui.IWorkbenchPart)
		 */
		public void partActivated(IWorkbenchPart part) {
			if (part == fTextEditor && hasJavaModelChanged())
				JavaReconciler.this.forceReconciling();
		}

		/*
		 * @see org.eclipse.ui.IPartListener#partBroughtToTop(org.eclipse.ui.IWorkbenchPart)
		 */
		public void partBroughtToTop(IWorkbenchPart part) {
		}

		/*
		 * @see org.eclipse.ui.IPartListener#partClosed(org.eclipse.ui.IWorkbenchPart)
		 */
		public void partClosed(IWorkbenchPart part) {
		}

		/*
		 * @see org.eclipse.ui.IPartListener#partDeactivated(org.eclipse.ui.IWorkbenchPart)
		 */
		public void partDeactivated(IWorkbenchPart part) {
			if (part == fTextEditor)
				setJavaModelChanged(false);
		}

		/*
		 * @see org.eclipse.ui.IPartListener#partOpened(org.eclipse.ui.IWorkbenchPart)
		 */
		public void partOpened(IWorkbenchPart part) {
		}
	}

	/**
	 * Internal Shell activation listener for activating the reconciler.
	 */
	private class ActivationListener extends ShellAdapter {

		private Control fControl;

		public ActivationListener(Control control) {
			fControl = control;
		}

		/*
		 * @see org.eclipse.swt.events.ShellListener#shellActivated(org.eclipse.swt.events.ShellEvent)
		 */
		public void shellActivated(ShellEvent e) {
			if (!fControl.isDisposed() && fControl.isVisible()
					&& hasJavaModelChanged())
				JavaReconciler.this.forceReconciling();
		}

		/*
		 * @see org.eclipse.swt.events.ShellListener#shellDeactivated(org.eclipse.swt.events.ShellEvent)
		 */
		public void shellDeactivated(ShellEvent e) {
			setJavaModelChanged(false);
		}
	}

	/**
	 * Internal Java element changed listener
	 * 
	 * @since 3.0
	 */
	private class ElementChangedListener implements IElementChangedListener {
		/*
		 * @see net.sourceforge.phpdt.core.IElementChangedListener#elementChanged(net.sourceforge.phpdt.core.ElementChangedEvent)
		 */
		public void elementChanged(ElementChangedEvent event) {
			setJavaModelChanged(true);
		}
	}

	/**
	 * Internal resource change listener.
	 * 
	 * @since 3.0
	 */
	class ResourceChangeListener implements IResourceChangeListener {

		private IResource getResource() {
			IEditorInput input = fTextEditor.getEditorInput();
			if (input instanceof IFileEditorInput) {
				IFileEditorInput fileInput = (IFileEditorInput) input;
				return fileInput.getFile();
			}
			return null;
		}

		/*
		 * @see IResourceChangeListener#resourceChanged(org.eclipse.core.resources.IResourceChangeEvent)
		 */
		public void resourceChanged(IResourceChangeEvent e) {
			IResourceDelta delta = e.getDelta();
			IResource resource = getResource();
			if (delta != null && resource != null) {
				IResourceDelta child = delta.findMember(resource.getFullPath());
				if (child != null) {
					IMarkerDelta[] deltas = child.getMarkerDeltas();
					if (deltas.length > 0)
						forceReconciling();
				}
			}
		}
	}

	/** The reconciler's editor */
	private ITextEditor fTextEditor;

	/** The part listener */
	private IPartListener fPartListener;

	/** The shell listener */
	private ShellListener fActivationListener;

	/**
	 * The mutex that keeps us from running multiple reconcilers on one editor.
	 * TODO remove once we have ensured that there is only one reconciler per
	 * editor.
	 */
	private Object fMutex;

	/**
	 * The Java element changed listener.
	 * 
	 * @since 3.0
	 */
	private IElementChangedListener fJavaElementChangedListener;

	/**
	 * Tells whether the Java model sent out a changed event.
	 * 
	 * @since 3.0
	 */
	private volatile boolean fHasJavaModelChanged = true;

	/**
	 * The resource change listener.
	 * 
	 * @since 3.0
	 */
	private IResourceChangeListener fResourceChangeListener;

	private boolean fIninitalProcessDone = false;

	/**
	 * Creates a new reconciler.
	 */
	public JavaReconciler(ITextEditor editor,
			JavaCompositeReconcilingStrategy strategy, boolean isIncremental) {
		super(strategy, isIncremental);
		fTextEditor = editor;

		// https://bugs.eclipse.org/bugs/show_bug.cgi?id=63898
		// when re-using editors, a new reconciler is set up by the source
		// viewer
		// and the old one uninstalled. However, the old reconciler may still be
		// running.
		// To avoid having to reconcilers calling
		// CompilationUnitEditor.reconciled,
		// we synchronized on a lock object provided by the editor.
		// The critical section is really the entire run() method of the
		// reconciler
		// thread, but synchronizing process() only will keep
		// JavaReconcilingStrategy
		// from running concurrently on the same editor.
		// TODO remove once we have ensured that there is only one reconciler
		// per editor.
		if (editor instanceof PHPUnitEditor)
			fMutex = ((PHPUnitEditor) editor).getReconcilerLock();
		else
			fMutex = new Object(); // Null Object
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.IReconciler#install(org.eclipse.jface.text.ITextViewer)
	 */
	public void install(ITextViewer textViewer) {
		super.install(textViewer);

		fPartListener = new PartListener();
		IWorkbenchPartSite site = fTextEditor.getSite();
		IWorkbenchWindow window = site.getWorkbenchWindow();
		window.getPartService().addPartListener(fPartListener);

		fActivationListener = new ActivationListener(textViewer.getTextWidget());
		Shell shell = window.getShell();
		shell.addShellListener(fActivationListener);

		fJavaElementChangedListener = new ElementChangedListener();
		JavaCore.addElementChangedListener(fJavaElementChangedListener);

		fResourceChangeListener = new ResourceChangeListener();
		IWorkspace workspace = PHPeclipsePlugin.getWorkspace();
		workspace.addResourceChangeListener(fResourceChangeListener);
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.IReconciler#uninstall()
	 */
	public void uninstall() {

		IWorkbenchPartSite site = fTextEditor.getSite();
		IWorkbenchWindow window = site.getWorkbenchWindow();
		window.getPartService().removePartListener(fPartListener);
		fPartListener = null;

		Shell shell = window.getShell();
		if (shell != null && !shell.isDisposed())
			shell.removeShellListener(fActivationListener);
		fActivationListener = null;

		JavaCore.removeElementChangedListener(fJavaElementChangedListener);
		fJavaElementChangedListener = null;

		IWorkspace workspace = PHPeclipsePlugin.getWorkspace();
		workspace.removeResourceChangeListener(fResourceChangeListener);
		fResourceChangeListener = null;

		super.uninstall();
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.AbstractReconciler#forceReconciling()
	 */
	protected void forceReconciling() {
		if (!fIninitalProcessDone)
			return;

		super.forceReconciling();
		JavaCompositeReconcilingStrategy strategy = (JavaCompositeReconcilingStrategy) getReconcilingStrategy(IDocument.DEFAULT_CONTENT_TYPE);
		strategy.notifyListeners(false);
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.AbstractReconciler#aboutToReconcile()
	 * @since 3.0
	 */
	protected void aboutToBeReconciled() {
		JavaCompositeReconcilingStrategy strategy = (JavaCompositeReconcilingStrategy) getReconcilingStrategy(IDocument.DEFAULT_CONTENT_TYPE);
		strategy.aboutToBeReconciled();
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.AbstractReconciler#reconcilerReset()
	 */
	protected void reconcilerReset() {
		super.reconcilerReset();
		JavaCompositeReconcilingStrategy strategy = (JavaCompositeReconcilingStrategy) getReconcilingStrategy(IDocument.DEFAULT_CONTENT_TYPE);
		strategy.notifyListeners(true);
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.MonoReconciler#initialProcess()
	 */
	protected void initialProcess() {
		// TODO remove once we have ensured that there is only one reconciler
		// per editor.
		synchronized (fMutex) {
			super.initialProcess();
		}
		fIninitalProcessDone = true;
	}

	/*
	 * @see org.eclipse.jface.text.reconciler.MonoReconciler#process(org.eclipse.jface.text.reconciler.DirtyRegion)
	 */
	protected void process(DirtyRegion dirtyRegion) {
		// TODO remove once we have ensured that there is only one reconciler
		// per editor.
		synchronized (fMutex) {
			super.process(dirtyRegion);
		}
	}

	/**
	 * Tells whether the Java Model has changed or not.
	 * 
	 * @return <code>true</code> iff the Java Model has changed
	 * @since 3.0
	 */
	private synchronized boolean hasJavaModelChanged() {
		return fHasJavaModelChanged;
	}

	/**
	 * Sets whether the Java Model has changed or not.
	 * 
	 * @param state
	 *            <code>true</code> iff the java model has changed
	 * @since 3.0
	 */
	private synchronized void setJavaModelChanged(boolean state) {
		fHasJavaModelChanged = state;
	}
}
// /**
// * A reconciler that is also activated on editor activation.
// */
// public class JavaReconciler extends MonoReconciler {
//	
// /**
// * Internal part listener for activating the reconciler.
// */
// class PartListener implements IPartListener {
//		
// /*
// * @see IPartListener#partActivated(IWorkbenchPart)
// */
// public void partActivated(IWorkbenchPart part) {
// if (part == fTextEditor)
// JavaReconciler.this.forceReconciling();
// }
//
// /*
// * @see IPartListener#partBroughtToTop(IWorkbenchPart)
// */
// public void partBroughtToTop(IWorkbenchPart part) {
// }
//
// /*
// * @see IPartListener#partClosed(IWorkbenchPart)
// */
// public void partClosed(IWorkbenchPart part) {
// }
//
// /*
// * @see IPartListener#partDeactivated(IWorkbenchPart)
// */
// public void partDeactivated(IWorkbenchPart part) {
// }
//
// /*
// * @see IPartListener#partOpened(IWorkbenchPart)
// */
// public void partOpened(IWorkbenchPart part) {
// }
// };
//	
//	
// /** The reconciler's editor */
// private ITextEditor fTextEditor;
// /** The part listener */
// private IPartListener fPartListener;
//	
//	
// /**
// * Creates a new reconciler.
// */
// public JavaReconciler(ITextEditor editor, IReconcilingStrategy strategy,
// boolean isIncremental) {
// super(strategy, isIncremental);
// fTextEditor= editor;
// }
//	
// /*
// * @see IReconciler#install(ITextViewer)
// */
// public void install(ITextViewer textViewer) {
// super.install(textViewer);
//		
// fPartListener= new PartListener();
// IWorkbenchPartSite site= fTextEditor.getSite();
// IWorkbenchWindow window= site.getWorkbenchWindow();
// window.getPartService().addPartListener(fPartListener);
// }
//
// /*
// * @see IReconciler#uninstall()
// */
// public void uninstall() {
//		
// IWorkbenchPartSite site= fTextEditor.getSite();
// IWorkbenchWindow window= site.getWorkbenchWindow();
// window.getPartService().removePartListener(fPartListener);
// fPartListener= null;
//		
// super.uninstall();
// }
//	
// /*
// * @see AbstractReconciler#forceReconciling()
// */
// protected void forceReconciling() {
// super.forceReconciling();
// IReconcilingStrategy strategy=
// getReconcilingStrategy(IDocument.DEFAULT_CONTENT_TYPE);
// if (strategy instanceof JavaReconcilingStrategy) {
// JavaReconcilingStrategy java= (JavaReconcilingStrategy) strategy;
// java.notifyParticipants(false);
// }
// }
//    
// /*
// * @see AbstractReconciler#reconcilerReset()
// */
// protected void reconcilerReset() {
// super.reconcilerReset();
// IReconcilingStrategy strategy=
// getReconcilingStrategy(IDocument.DEFAULT_CONTENT_TYPE);
// if (strategy instanceof JavaReconcilingStrategy) {
// JavaReconcilingStrategy java= (JavaReconcilingStrategy) strategy;
// java.notifyParticipants(true);
// }
// }
// }