/*******************************************************************************
 * Copyright (c) 2009 Luaj.org. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 * 
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 ******************************************************************************/
package org.luaj.vm2.libs.jme;

import org.luaj.vm2.Globals;
import org.luaj.vm2.LoadState;
import org.luaj.vm2.compiler.LuaC;
import org.luaj.vm2.libs.*;

/** The {@link JmePlatform} class is a convenience class to standardize
 * how globals tables are initialized for the JME platform. 
 * <p>
 * The JME platform, being limited, cannot implement all libraries in all aspects.  The main limitations are
 * <ul>
 * <li>Some math functions are not implemented, see {@link MathLib} for details</li>
 * <li>Scripts are loaded via Class.getResourceAsStream(), see {@link BaseLib} for details</li>
 * <li>OS functions execute(), remove(), rename(), and tmpname() vary, see {@link OsLib} for details</li>
 * <li>I/O seek is not implemented, see {@link JmeIoLib} for details</li>
 * <li>luajava is not available, see {@link org.luaj.vm2.libs.jse.LuajavaLib} for details</li>
 * </ul>
 * <p>
 * It is used to allocate either a set of standard globals using 
 * {@link #standardGlobals()} or debug globals using {@link #debugGlobals()}
 * <p>
 * A simple example of initializing globals and using them from Java is:
 * <pre> {@code
 * Globals global = JmePlatform.standardGlobals();
 * global.get("print").call(LuaValue.valueOf("hello, world"));
 * } </pre>
 * <p>
 * Once globals are created, a simple way to load and run a script is:
 * <pre> {@code
 * LoadState.load( getClass().getResourceAsStream("main.lua"), "main.lua", globals ).call();
 * } </pre>
 * <p>
 * although {@code require} could also be used: 
 * <pre> {@code
 * globals.get("require").call(LuaValue.valueOf("main"));
 * } </pre>
 * For this to succeed, the file "main.lua" must be a resource in the class path.
 * See {@link BaseLib} for details on finding scripts using {@link ResourceFinder}.
 * <p>
 * The standard globals will contain all standard libraries in their JME flavors:
 * <ul>
 * <li>{@link Globals}</li>
 * <li>{@link BaseLib}</li>
 * <li>{@link PackageLib}</li>
 * <li>{@link TableLib}</li>
 * <li>{@link StringLib}</li>
 * <li>{@link CoroutineLib}</li>
 * <li>{@link MathLib}</li>
 * <li>{@link JmeIoLib}</li>
 * <li>{@link OsLib}</li>
 * </ul>
 * In addition, the {@link LuaC} compiler is installed so lua files may be loaded in their source form. 
 * <p> 
 * The debug globals are simply the standard globals plus the {@code debug} library {@link DebugLib}.
 * <p>
 * <p>
 * The class ensures that initialization is done in the correct order.  
 * 
 * @see Globals
 * @see org.luaj.vm2.libs.jse.JsePlatform
 */
public class JmePlatform {

	/**
	 * Create a standard set of globals for JME including all the libraries.
	 * 
	 * @return Table of globals initialized with the standard JME libraries
	 * @see #debugGlobals()
	 * @see org.luaj.vm2.libs.jse.JsePlatform
	 * @see JmePlatform
	 */
	public static Globals standardGlobals() {
		Globals globals = new Globals();
		globals.load(new BaseLib());
		globals.load(new PackageLib());
		globals.load(new CjsonLib());
		globals.load(new OsLib());
		globals.load(new MathLib());
		globals.load(new TableLib());
		globals.load(new StringLib());
		globals.load(new Utf8Lib());
		globals.load(new CoroutineLib());
		globals.load(new JmeIoLib());
		LoadState.install(globals);
		LuaC.install(globals);
		return globals;		
	}
	
	/** Create standard globals including the {@link DebugLib} library.
	 * 
	 * @return Table of globals initialized with the standard JSE and debug libraries
	 * @see #standardGlobals()
	 * @see org.luaj.vm2.libs.jse.JsePlatform
	 * @see JmePlatform
	 * @see DebugLib
	 */
	public static Globals debugGlobals() {
		Globals globals = standardGlobals();
		globals.load(new DebugLib());
		return globals;
	}
}
