/*******************************************************************************
 * Copyright (c) 2000, 2013 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.debug.ui.console;


import org.eclipse.core.resources.IFile;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.content.IContentDescription;
import org.eclipse.core.runtime.content.IContentType;
import org.eclipse.debug.internal.ui.DebugUIPlugin;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.ui.IEditorDescriptor;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IEditorPart;
import org.eclipse.ui.IEditorRegistry;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.IWorkbenchWindow;
import org.eclipse.ui.PartInitException;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.part.FileEditorInput;
import org.eclipse.ui.texteditor.IDocumentProvider;
import org.eclipse.ui.texteditor.ITextEditor;

/**
 * A hyperlink that opens a file in a text editor and selects a range of text.
 * This hyperlink action will un-zoom the workbench as needed to show the editor
 * for the associated link.
 * <p>
 * Clients may instantiate this class.
 * </p>
 * @since 2.1
 * @noextend This class is not intended to be subclassed by clients.
 */
@SuppressWarnings("deprecation")
public class FileLink implements IConsoleHyperlink {

	private final IFile fFile;
	private int fFileOffset;
	private int fFileLength;
	private final int fFileLineNumber;
	private String fEditorId;

	/**
	 * Constructs a hyperlink to the specified file.
	 *
	 * @param file           the file to open when activated
	 * @param editorId       the identifier of the editor to open the file in, or
	 *                       <code>null</code> if the default editor should be used
	 * @param fileOffset     the offset in the file to select when activated, or -1
	 * @param fileLength     the length of text to select in the file when activated
	 *                       or -1
	 * @param fileLineNumber the line number to select in the file when activated,
	 *                       or -1. First line number is 1. Only used if
	 *                       <em>fileOffset</em> is not set.
	 */
	public FileLink(IFile file, String editorId, int fileOffset, int fileLength, int fileLineNumber) {
		fFile = file;
		fFileOffset = fileOffset;
		fFileLength = fileLength;
		fFileLineNumber = fileLineNumber;
		fEditorId = editorId;
	}

	@Override
	public void linkActivated() {
		IWorkbenchWindow window = DebugUIPlugin.getActiveWorkbenchWindow();
		if (window != null) {
			IWorkbenchPage page = window.getActivePage();
			if (page != null) {
				try {
					IEditorPart editorPart = page.openEditor(new FileEditorInput(fFile), getEditorId() , true);
					if (fFileLineNumber > 0 || (fFileOffset >= 0 && fFileLength >= 0)) {
						ITextEditor textEditor = null;
						if (editorPart instanceof ITextEditor) {
							textEditor = (ITextEditor) editorPart;
						} else {
							textEditor = editorPart.getAdapter(ITextEditor.class);
						}
						if (textEditor != null) {
							if (fFileOffset < 0) {
								IEditorInput input = editorPart.getEditorInput();
								IDocumentProvider provider = textEditor.getDocumentProvider();
								try {
									provider.connect(input);
								} catch (CoreException e) {
									// unable to link
									DebugUIPlugin.log(e);
									return;
								}
								IDocument document = provider.getDocument(input);
								try {
									IRegion region= document.getLineInformation(fFileLineNumber - 1);
									fFileOffset = region.getOffset();
									fFileLength = region.getLength();
								} catch (BadLocationException e) {
									// unable to link
									DebugUIPlugin.log(e);
								}
								provider.disconnect(input);
							}
							if (fFileOffset >= 0 && fFileLength >=0) {
								textEditor.selectAndReveal(fFileOffset, fFileLength);
							}
						}
					}
				} catch (PartInitException e) {
					DebugUIPlugin.log(e);
				}
			}
		}
	}

	@Override
	public void linkEntered() {
	}

	@Override
	public void linkExited() {
	}

	private String getEditorId() {
		if (fEditorId == null) {
			IWorkbench workbench= PlatformUI.getWorkbench();
			// If there is a registered editor for the file use it.
			IEditorDescriptor desc = workbench.getEditorRegistry().getDefaultEditor(fFile.getName(), getFileContentType());
			if (desc == null) {
				//default editor
				desc= workbench.getEditorRegistry().findEditor(IEditorRegistry.SYSTEM_EXTERNAL_EDITOR_ID);
			}
			fEditorId= desc.getId();
		}
		return fEditorId;
	}

	private IContentType getFileContentType() {
		try {
			IContentDescription description= fFile.getContentDescription();
			if (description != null) {
				return description.getContentType();
			}
		} catch (CoreException e) {
		}
		return null;
	}
}
