/* 
 * Copyright (c) 2002 Lightweight Java Game Library Project
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are 
 * met:
 * 
 * * Redistributions of source code must retain the above copyright 
 *   notice, this list of conditions and the following disclaimer.
 *
 * * Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 *
 * * Neither the name of 'Light Weight Java Game Library' nor the names of 
 *   its contributors may be used to endorse or promote products derived 
 *   from this software without specific prior written permission.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR 
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 package org.lwjgl.openal;

import java.io.File;
import java.util.StringTokenizer;

/**
 * $Id$
 *
 * The base AL functionality (no actual AL methods).
 *
 * This has been provided as a base class that we can use for either the
 * full AL 1.0 specification or as a cut-down OpenAL embedded spec. (aka
 * a mini-driver).
 *
 * @author Brian Matzon <brian@matzon.dk>
 * @version $Revision$
 */
public abstract class BaseAL {
	/** Has the ALC object been created? */
	protected static boolean created;
    
	static {
		initialize();
	}
    
    /**
	 * Override to provide any initialization code after creation.
	 */
	protected void init() {
	}
    
	/**
	 * Static initialization
	 */
	private static void initialize() {
		System.loadLibrary(org.lwjgl.Sys.getLibraryName());
	}
    
    /**
	 * Creates the AL instance
	 * 
	 * @throws Exception if a failiure occured in the AL creation process
	 */
	public void create() throws Exception {
		if (created) {
			return;
		}

		// need to pass path of possible locations of OAL to native side
		String libpath = System.getProperty("java.library.path");
		String seperator = System.getProperty("path.separator");
		String libname;

		// libname is hardcoded atm - this will change in a near future...
		libname = (System.getProperty("os.name").toLowerCase().indexOf("windows") == -1) 
		        ? "libopenal.so" 
		        : "OpenAL32.dll";     

		StringTokenizer st = new StringTokenizer(libpath, seperator);
            
		//create needed string array
		String[] oalPaths = new String[st.countTokens()+1];

		//build paths
		for(int i=0;i<oalPaths.length - 1;i++) {
			oalPaths[i] = st.nextToken() + File.separator + libname; 
		}

		//add cwd path
		oalPaths[oalPaths.length-1] = libname;
		if (!nCreate(oalPaths)) {
			throw new Exception("AL instance could not be created.");
                }
		created = true;
                init();
	}
	
	/**
	 * Native method to create AL instance
	 * 
	 * @return true if the AL creation process succeeded
	 */
	protected native boolean nCreate(String[] oalPaths);
    
	/**
	 * Calls whatever destruction rutines that are needed
	 */
	public void destroy() {
		if (!created) {
			return;
        }
        created = false;
        nDestroy();
	}
	
	/**
	 * Native method the destroy the AL
	 */
	protected native void nDestroy();    
}