/*******************************************************************************
 * Copyright (c) 2000, 2006 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package net.sourceforge.phpdt.internal.ui.text.java.hover;

import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import net.sourceforge.phpdt.internal.ui.text.java.hover.AnnotationExpansionControl.AnnotationHoverInput;

import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IInformationControl;
import org.eclipse.jface.text.IInformationControlCreator;
import org.eclipse.jface.text.IInformationControlCreatorExtension;
import org.eclipse.jface.text.ITextViewerExtension5;
import org.eclipse.jface.text.Position;
import org.eclipse.jface.text.TextViewer;
import org.eclipse.jface.text.source.Annotation;
import org.eclipse.jface.text.source.CompositeRuler;
import org.eclipse.jface.text.source.IAnnotationAccess;
import org.eclipse.jface.text.source.IAnnotationAccessExtension;
import org.eclipse.jface.text.source.IAnnotationHover;
import org.eclipse.jface.text.source.IAnnotationHoverExtension;
import org.eclipse.jface.text.source.IAnnotationModel;
import org.eclipse.jface.text.source.ILineRange;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.IVerticalRulerListener;
import org.eclipse.jface.text.source.LineRange;
import org.eclipse.jface.text.source.VerticalRulerEvent;
import org.eclipse.jface.viewers.IDoubleClickListener;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.widgets.Menu;
import org.eclipse.swt.widgets.Shell;

/**
 * This class got moved here form Platform Text since it was not used there and
 * caused discouraged access warnings. It will be moved down again once
 * annotation roll-over support is provided by Platform Text.
 * 
 * @since 3.2
 */
public class AnnotationExpandHover implements IAnnotationHover,
		IAnnotationHoverExtension {

	private class InformationControlCreator implements
			IInformationControlCreator, IInformationControlCreatorExtension {

		/*
		 * @see org.eclipse.jface.text.IInformationControlCreator#createInformationControl(org.eclipse.swt.widgets.Shell)
		 */
		public IInformationControl createInformationControl(Shell parent) {
			return new AnnotationExpansionControl(parent, SWT.NONE,
					fAnnotationAccess);
		}

		/*
		 * @see org.eclipse.jface.text.IInformationControlCreatorExtension#canReuse(org.eclipse.jface.text.IInformationControl)
		 */
		public boolean canReuse(IInformationControl control) {
			return control instanceof AnnotationExpansionControl;
		}

		/*
		 * @see org.eclipse.jface.text.IInformationControlCreatorExtension#canReplace(org.eclipse.jface.text.IInformationControlCreator)
		 */
		public boolean canReplace(IInformationControlCreator creator) {
			return creator == this;
		}
	}

	private class VerticalRulerListener implements IVerticalRulerListener {

		/*
		 * @see org.eclipse.jface.text.source.IVerticalRulerListener#annotationSelected(org.eclipse.jface.text.source.VerticalRulerEvent)
		 */
		public void annotationSelected(VerticalRulerEvent event) {
			fCompositeRuler.fireAnnotationSelected(event);
		}

		/*
		 * @see org.eclipse.jface.text.source.IVerticalRulerListener#annotationDefaultSelected(org.eclipse.jface.text.source.VerticalRulerEvent)
		 */
		public void annotationDefaultSelected(VerticalRulerEvent event) {
			fCompositeRuler.fireAnnotationDefaultSelected(event);
		}

		/*
		 * @see org.eclipse.jface.text.source.IVerticalRulerListener#annotationContextMenuAboutToShow(org.eclipse.jface.text.source.VerticalRulerEvent,
		 *      org.eclipse.swt.widgets.Menu)
		 */
		public void annotationContextMenuAboutToShow(VerticalRulerEvent event,
				Menu menu) {
			fCompositeRuler.fireAnnotationContextMenuAboutToShow(event, menu);
		}
	}

	private final IInformationControlCreator fgCreator = new InformationControlCreator();

	protected final IVerticalRulerListener fgListener = new VerticalRulerListener();

	protected CompositeRuler fCompositeRuler;

	protected IDoubleClickListener fDblClickListener;

	protected IAnnotationAccess fAnnotationAccess;

	/**
	 * Creates a new hover instance.
	 * 
	 * @param ruler
	 * @param access
	 * @param doubleClickListener
	 */
	public AnnotationExpandHover(CompositeRuler ruler,
			IAnnotationAccess access, IDoubleClickListener doubleClickListener) {
		fCompositeRuler = ruler;
		fAnnotationAccess = access;
		fDblClickListener = doubleClickListener;
	}

	/*
	 * @see org.eclipse.jface.text.source.IAnnotationHover#getHoverInfo(org.eclipse.jface.text.source.ISourceViewer,
	 *      int)
	 */
	public String getHoverInfo(ISourceViewer sourceViewer, int line) {
		// we don't have any sensible return value as text
		return null;
	}

	protected Object getHoverInfoForLine(ISourceViewer viewer, int line) {
		IAnnotationModel model = viewer.getAnnotationModel();
		IDocument document = viewer.getDocument();

		if (model == null)
			return null;

		List exact = new ArrayList();
		HashMap messagesAtPosition = new HashMap();

		Iterator e = model.getAnnotationIterator();
		while (e.hasNext()) {
			Annotation annotation = (Annotation) e.next();
			Position position = model.getPosition(annotation);
			if (position == null)
				continue;

			if (compareRulerLine(position, document, line) == 1) {
				if (isDuplicateMessage(messagesAtPosition, position, annotation
						.getText()))
					continue;

				exact.add(annotation);
			}
		}

		if (exact.size() < 1)
			return null;

		sort(exact, model);

		if (exact.size() > 0)
			setLastRulerMouseLocation(viewer, line);

		AnnotationHoverInput input = new AnnotationHoverInput();
		input.fAnnotations = (Annotation[]) exact.toArray(new Annotation[0]);
		input.fViewer = viewer;
		input.fRulerInfo = fCompositeRuler;
		input.fAnnotationListener = fgListener;
		input.fDoubleClickListener = fDblClickListener;
		input.model = model;

		return input;
	}

	protected void sort(List exact, final IAnnotationModel model) {
		class AnnotationComparator implements Comparator {

			/*
			 * @see java.util.Comparator#compare(java.lang.Object,
			 *      java.lang.Object)
			 */
			public int compare(Object o1, Object o2) {
				Annotation a1 = (Annotation) o1;
				Annotation a2 = (Annotation) o2;

				Position p1 = model.getPosition(a1);
				Position p2 = model.getPosition(a2);

				// annotation order:
				// primary order: by position in line
				// secondary: annotation importance
				if (p1.offset == p2.offset)
					return getOrder(a2) - getOrder(a1);
				return p1.offset - p2.offset;
			}
		}

		Collections.sort(exact, new AnnotationComparator());

	}

	protected int getOrder(Annotation annotation) {
		if (fAnnotationAccess instanceof IAnnotationAccessExtension) {
			IAnnotationAccessExtension extension = (IAnnotationAccessExtension) fAnnotationAccess;
			return extension.getLayer(annotation);
		}
		return IAnnotationAccessExtension.DEFAULT_LAYER;
	}

	protected boolean isDuplicateMessage(Map messagesAtPosition,
			Position position, String message) {
		if (message == null)
			return false;

		if (messagesAtPosition.containsKey(position)) {
			Object value = messagesAtPosition.get(position);
			if (message == null || message.equals(value))
				return true;

			if (value instanceof List) {
				List messages = (List) value;
				if (messages.contains(message))
					return true;
				messages.add(message);
			} else {
				ArrayList messages = new ArrayList();
				messages.add(value);
				messages.add(message);
				messagesAtPosition.put(position, messages);
			}
		} else
			messagesAtPosition.put(position, message);
		return false;
	}

	protected void setLastRulerMouseLocation(ISourceViewer viewer, int line) {
		// set last mouse activity in order to get the correct context menu
		if (fCompositeRuler != null) {
			StyledText st = viewer.getTextWidget();
			if (st != null && !st.isDisposed()) {
				if (viewer instanceof ITextViewerExtension5) {
					int widgetLine = ((ITextViewerExtension5) viewer)
							.modelLine2WidgetLine(line);
					Point loc = st.getLocationAtOffset(st
							.getOffsetAtLine(widgetLine));
					fCompositeRuler.setLocationOfLastMouseButtonActivity(0,
							loc.y);
				} else if (viewer instanceof TextViewer) {
					// TODO remove once TextViewer implements the extension
					int widgetLine = ((TextViewer) viewer)
							.modelLine2WidgetLine(line);
					Point loc = st.getLocationAtOffset(st
							.getOffsetAtLine(widgetLine));
					fCompositeRuler.setLocationOfLastMouseButtonActivity(0,
							loc.y);
				}
			}
		}
	}

	/**
	 * Returns the distance to the ruler line.
	 * 
	 * @param position
	 *            the position
	 * @param document
	 *            the document
	 * @param line
	 *            the line number
	 * @return the distance to the ruler line
	 */
	protected int compareRulerLine(Position position, IDocument document,
			int line) {

		if (position.getOffset() > -1 && position.getLength() > -1) {
			try {
				int firstLine = document.getLineOfOffset(position.getOffset());
				if (line == firstLine)
					return 1;
				if (firstLine <= line
						&& line <= document.getLineOfOffset(position
								.getOffset()
								+ position.getLength()))
					return 2;
			} catch (BadLocationException x) {
			}
		}

		return 0;
	}

	/*
	 * @see org.eclipse.jface.text.source.IAnnotationHoverExtension#getHoverControlCreator()
	 */
	public IInformationControlCreator getHoverControlCreator() {
		return fgCreator;
	}

	/*
	 * @see org.eclipse.jface.text.source.IAnnotationHoverExtension#getHoverInfo(org.eclipse.jface.text.source.ISourceViewer,
	 *      org.eclipse.jface.text.source.ILineRange, int)
	 */
	public Object getHoverInfo(ISourceViewer sourceViewer,
			ILineRange lineRange, int visibleLines) {
		return getHoverInfoForLine(sourceViewer, lineRange.getStartLine());
	}

	/*
	 * @see org.eclipse.jface.text.source.IAnnotationHoverExtension#getHoverLineRange(org.eclipse.jface.text.source.ISourceViewer,
	 *      int)
	 */
	public ILineRange getHoverLineRange(ISourceViewer viewer, int lineNumber) {
		return new LineRange(lineNumber, 1);
	}

	/*
	 * @see org.eclipse.jface.text.source.IAnnotationHoverExtension#canHandleMouseCursor()
	 */
	public boolean canHandleMouseCursor() {
		return true;
	}
}
