/*******************************************************************************
 * Copyright (c) 2005, 2007 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
 *******************************************************************************/
package org.eclipse.dltk.ui.templates;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.dltk.core.DLTKCore;
import org.eclipse.dltk.core.DLTKLanguageManager;
import org.eclipse.dltk.core.IDLTKLanguageToolkit;
import org.eclipse.dltk.core.ISourceModule;
import org.eclipse.dltk.launching.IInterpreterInstall;
import org.eclipse.dltk.launching.ScriptRuntime;
import org.eclipse.jface.text.templates.TemplateContext;
import org.eclipse.jface.text.templates.TemplateVariableResolver;

public final class ScriptTemplateVariables {
	private ScriptTemplateVariables() {
	}

	public static class File extends TemplateVariableResolver {
		public static final String NAME = "file"; //$NON-NLS-1$

		public File() {
			super(NAME, TemplateMessages.Variable_File_Description);
		}

		protected String resolve(TemplateContext context) {
			ISourceModule module = getSourceModule(context);
			return (module == null) ? null : module.getElementName();
		}

		protected boolean isUnambiguous(TemplateContext context) {
			return resolve(context) != null;
		}
	}

	public static class Language extends TemplateVariableResolver {
		public static final String NAME = "language"; //$NON-NLS-1$

		public Language() {
			super(NAME, TemplateMessages.Variable_Language_Description);
		}

		protected String resolve(TemplateContext context) {
			String name = null;
			ISourceModule module = getSourceModule(context);
			IDLTKLanguageToolkit toolkit = DLTKLanguageManager
					.getLanguageToolkit(module);

			name = toolkit.getLanguageName();

			return name;
		}

		protected boolean isUnambiguous(TemplateContext context) {
			return resolve(context) != null;
		}
	}

	public static class Interpreter extends TemplateVariableResolver {
		public static final String NAME = "interpreter"; //$NON-NLS-1$

		public Interpreter() {
			super(NAME, TemplateMessages.Variable_Interpreter_Description);
		}

		protected String resolve(TemplateContext context) {
			final ISourceModule module = getSourceModule(context);
			if (module != null) {
				try {
					final IInterpreterInstall install = ScriptRuntime
							.getInterpreterInstall(module.getScriptProject());
					if (install != null) {
						return install.getRawInstallLocation().toOSString();
					}
				} catch (CoreException e) {
					if (DLTKCore.DEBUG) {
						e.printStackTrace();
					}
				}
			}
			return null;
		}

		protected boolean isUnambiguous(TemplateContext context) {
			return resolve(context) != null;
		}
	}

	private static ISourceModule getSourceModule(TemplateContext context) {
		return ((IScriptTemplateContext) context).getSourceModule();
	}

}