/*******************************************************************************
 * Copyright (c) 2006, 2012 Wind River Systems, Inc. and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *    Markus Schorn - initial API and implementation
 *    Ed Swartz (Nokia)
 *******************************************************************************/
package org.eclipse.cdt.internal.ui.viewsupport;

import java.net.URI;

import org.eclipse.cdt.core.CCorePlugin;
import org.eclipse.cdt.core.IPositionConverter;
import org.eclipse.cdt.core.model.CModelException;
import org.eclipse.cdt.core.model.ICElement;
import org.eclipse.cdt.core.model.ISourceRange;
import org.eclipse.cdt.core.model.ISourceReference;
import org.eclipse.cdt.core.model.ITranslationUnit;
import org.eclipse.cdt.internal.core.model.ext.ICElementHandle;
import org.eclipse.cdt.internal.ui.util.EditorUtility;
import org.eclipse.cdt.internal.ui.util.StatusLineHandler;
import org.eclipse.cdt.ui.CUIPlugin;
import org.eclipse.core.filesystem.EFS;
import org.eclipse.core.resources.IFile;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPath;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.Region;
import org.eclipse.osgi.util.NLS;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchPartSite;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.ide.IDE;
import org.eclipse.ui.texteditor.ITextEditor;

/**
 * An utility to open editors for references or elements.
 */
public class EditorOpener {

	/**
	 * Opens the editor selecting the given region.
	 */
	public static void open(IWorkbenchPage page, IFile file, IRegion region, long timestamp) {
		if (file.getLocationURI() != null) {
			IEditorPart editor = null;
			if (timestamp == 0) {
				timestamp = file.getLocalTimeStamp();
			}
			try {
				// Bug 328321: Linked resources of closed projects report wrong location.
				if (!file.exists()) {
					final IWorkbenchPartSite site = page.getActivePart().getSite();
					showStatus(site, 3000, NLS.bind(Messages.EditorOpener_fileDoesNotExist, file.getName()));
					return;
				}
				editor = IDE.openEditor(page, file, false);
			} catch (PartInitException e) {
				CUIPlugin.log(e);
			}
			selectRegion(file.getFullPath(), region, timestamp, editor);
		}
	}

	private static void showStatus(final IWorkbenchPartSite site, int duration, String msg) {
		StatusLineHandler.showStatusLineMessage(site, msg);
		Display.getCurrent().timerExec(duration, () -> StatusLineHandler.clearStatusLine(site));
	}

	private static void selectRegion(IPath filebufferKey, IRegion region, long timestamp, IEditorPart editor) {
		if (editor instanceof ITextEditor) {
			ITextEditor te = (ITextEditor) editor;
			IPositionConverter pc = CCorePlugin.getPositionTrackerManager().findPositionConverter(filebufferKey,
					timestamp);
			if (pc != null) {
				region = pc.historicToActual(region);
			}
			te.selectAndReveal(region.getOffset(), region.getLength());
		}
	}

	private static void selectRegion(URI locationURI, IRegion region, long timestamp, IEditorPart editor) {
		if (editor instanceof ITextEditor) {
			ITextEditor te = (ITextEditor) editor;
			IPositionConverter pc = CCorePlugin.getPositionTrackerManager().findPositionConverter(locationURI,
					timestamp);
			if (pc != null) {
				region = pc.historicToActual(region);
			}
			te.selectAndReveal(region.getOffset(), region.getLength());
		}
	}

	/**
	 * Opens the editor for an external location, selecting the given region.
	 */
	public static void openExternalFile(IWorkbenchPage page, IPath location, IRegion region, long timestamp) {
		IEditorPart editor = null;
		try {
			editor = EditorUtility.openInEditor(location, null);
			if (timestamp == 0) {
				timestamp = location.toFile().lastModified();
			}
			selectRegion(location, region, timestamp, editor);
		} catch (PartInitException e) {
			CUIPlugin.log(e);
		}
	}

	/**
	 * Opens the editor for an external EFS location, selecting the given region.
	 */
	public static void openExternalFile(IWorkbenchPage page, URI locationURI, IRegion region, long timestamp,
			ICElement context) {
		IEditorPart editor = null;
		try {
			editor = EditorUtility.openInEditor(locationURI, context);
			if (timestamp == 0) {
				try {
					timestamp = EFS.getStore(locationURI).fetchInfo().getLastModified();
				} catch (CoreException e) {
					CUIPlugin.log(e);
				}
			}
			selectRegion(locationURI, region, timestamp, editor);
		} catch (PartInitException e) {
			CUIPlugin.log(e);
		}
	}

	/**
	 * Opens the editor for an ICElement, selecting the id.
	 * @throws CModelException
	 */
	public static void open(IWorkbenchPage page, ICElement element) throws CModelException {
		if (element instanceof ISourceReference) {
			ISourceReference sr = (ISourceReference) element;
			ITranslationUnit tu = sr.getTranslationUnit();
			ISourceRange range = sr.getSourceRange();
			long timestamp = 0; // last modified of file.
			if (tu.isWorkingCopy() || element instanceof ICElementHandle) {
				timestamp = -1;
			}
			open(page, tu, new Region(range.getIdStartPos(), range.getIdLength()), timestamp);
		}
	}

	/**
	 * Opens the editor for an ICElement, selecting the given region.
	 */
	public static void open(IWorkbenchPage page, ITranslationUnit tu, Region region, long timestamp) {
		if (tu != null) {
			IResource r = tu.getResource();
			if (r instanceof IFile) {
				if (r.getLocationURI() != null) {
					EditorOpener.open(page, (IFile) r, region, timestamp);
				}
			} else {
				IPath location = tu.getPath();
				if (location != null) {
					EditorOpener.openExternalFile(page, location, region, timestamp);
				}
			}
		}
	}
}
