package org.eclipse.wst.sse.ui.internal.hyperlink;

import java.util.ResourceBundle;

import org.eclipse.core.runtime.SafeRunner;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextSelection;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.Region;
import org.eclipse.jface.text.hyperlink.IHyperlink;
import org.eclipse.jface.text.hyperlink.IHyperlinkDetector;
import org.eclipse.jface.util.SafeRunnable;
import org.eclipse.jface.viewers.ISelection;
import org.eclipse.ui.texteditor.ITextEditor;
import org.eclipse.ui.texteditor.TextEditorAction;

/**
 * Open hyperlink action
 */
public class OpenHyperlinkAction extends TextEditorAction {
	private IHyperlinkDetector[] fHyperlinkDetectors;
	private ITextViewer fTextViewer;

	public OpenHyperlinkAction(ResourceBundle bundle, String prefix, ITextEditor editor, ITextViewer viewer) {
		super(bundle, prefix, editor);
		fTextViewer = viewer;
	}

	public void setHyperlinkDetectors(IHyperlinkDetector[] detectors) {
		fHyperlinkDetectors = detectors;
	}

	public void run() {
		if (fHyperlinkDetectors == null)
			return;
		ISelection selection = getTextEditor().getSelectionProvider().getSelection();
		if (selection == null || !(selection instanceof ITextSelection)) {
			return;
		}

		ITextSelection textSelection = (ITextSelection) selection;
		final IRegion region = new Region(textSelection.getOffset(), textSelection.getLength());
		IHyperlink hyperlink = null;

		synchronized (fHyperlinkDetectors) {
			for (int i = 0, length = fHyperlinkDetectors.length; i < length && hyperlink == null; i++) {
				final IHyperlinkDetector detector = fHyperlinkDetectors[i];
				if (detector == null)
					continue;

				/* The array is final, but its contents aren't */
				final IHyperlink[][] hyperlinks = new IHyperlink[1][];

				/*
				 * Detect from within a SafeRunnable since the list of
				 * detectors is extensible
				 */
				SafeRunnable detectorRunnable = new SafeRunnable() {
					public void run() throws Exception {
						hyperlinks[0] = detector.detectHyperlinks(fTextViewer, region, false);
					}
				};
				SafeRunner.run(detectorRunnable);

				if (hyperlinks[0] == null)
					continue;

				if (hyperlinks.length > 0)
					hyperlink = hyperlinks[0][0];
			}
		}
		if (hyperlink != null) {
			/**
			 * Force the highlight range to change when the hyperlink is
			 * opened by altering the highlighted range beforehand.
			 */
			getTextEditor().setHighlightRange(Math.max(0, region.getOffset() - 1), 0, false);
			hyperlink.open();
		}
	}
}