/*******************************************************************************
 * Copyright (c) 2009-2012 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.cli;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.List;

import org.luaj.vm2.Globals;
import org.luaj.vm2.Lua;
import org.luaj.vm2.libs.jse.JsePlatform;
import org.luaj.vm2.luajc.LuaJC;

/**
 * Compiler for lua files to compile lua sources or lua binaries into java classes.
 */
public class luajc {
	private static final String version = Lua._VERSION + " Copyright (C) 2012 luaj.org";

	private static final String usage =
			"usage: java -cp luaj-jse.jar,bcel-5.2.jar org.luaj.vm2.cli.luajc [options] fileordir [, fileordir ...]\n" +
					"Available options are:\n" +
					"  -        process stdin\n" +
					"  -s src	source directory\n" +
					"  -d dir	destination directory\n" +
					"  -p pkg	package prefix to apply to all classes\n" +
					"  -m		generate main(String[]) function for JSE\n" +
					"  -r		recursively compile all\n" +
					"  -l		load classes to verify generated bytecode\n" +
					"  -c enc  	use the supplied encoding 'enc' for input files\n" +
					"  -v   	verbose\n";

	private static void usageExit() {
		System.out.println(usage);
		System.exit(-1);
	}

	private String srcdir = ".";
	private String destdir = ".";
	private boolean genmain = false;
	private boolean recurse = false;
	private boolean verbose = false;
	private boolean loadclasses = false;
	private String encoding = null;
	private String pkgprefix = null;
	private List files = new ArrayList();
	private Globals globals;

	public static void main( String[] args ) throws IOException {
		new luajc( args );
	}

	private luajc( String[] args ) throws IOException {

		// process args
		List seeds = new ArrayList ();

		// get stateful args
		for ( int i=0; i<args.length; i++ ) {
			if ( ! args[i].startsWith("-") ) {
				seeds.add(args[i]);
			} else {
				switch ( args[i].charAt(1) ) {
					case 's':
						if ( ++i >= args.length )
							usageExit();
						srcdir = args[i];
						break;
					case 'd':
						if ( ++i >= args.length )
							usageExit();
						destdir = args[i];
						break;
					case 'l':
						loadclasses = true;
						break;
					case 'p':
						if ( ++i >= args.length )
							usageExit();
						pkgprefix = args[i];
						break;
					case 'm':
						genmain = true;
						break;
					case 'r':
						recurse = true;
						break;
					case 'c':
						if ( ++i >= args.length )
							usageExit();
						encoding = args[i];
						break;
					case 'v':
						verbose = true;
						break;
					default:
						usageExit();
						break;
				}
			}
		}

		// echo version
		if ( verbose ) {
			System.out.println(version);
			System.out.println("srcdir: "+srcdir);
			System.out.println("destdir: "+destdir);
			System.out.println("files: "+seeds);
			System.out.println("recurse: "+recurse);
		}

		// need at least one seed
		if ( seeds.size() <= 0 ) {
			System.err.println(usage);
			System.exit(-1);
		}

		// collect up files to process
		for ( int i=0; i<seeds.size(); i++ )
			collectFiles( srcdir+"/"+seeds.get(i) );

		// check for at least one file
		if ( files.size() <= 0 ) {
			System.err.println("no files found in "+seeds);
			System.exit(-1);
		}

		// process input files
		globals = JsePlatform.standardGlobals();
		for ( int i=0,n=files.size(); i<n; i++ )
			processFile( (InputFile) files.get(i) );
	}

	private void collectFiles(String path) {
		File f = new File(path);
		if ( f.isDirectory() && recurse )
			scandir(f,pkgprefix);
		else if ( f.isFile() ) {
			File dir = f.getAbsoluteFile().getParentFile();
			if ( dir != null )
				scanfile( dir, f, pkgprefix );
		}
	}
	private void scandir(File dir, String javapackage) {
		File[] f = dir.listFiles();
		for ( int i=0; i<f.length; i++ )
			scanfile( dir, f[i], javapackage );
	}

	private void scanfile(File dir, File f, String javapackage) {
		if ( f.exists() ) {
			if ( f.isDirectory() && recurse )
				scandir( f, (javapackage!=null? javapackage+"."+f.getName(): f.getName()) );
			else if ( f.isFile() && f.getName().endsWith(".lua") )
				files.add( new InputFile(dir,f,javapackage) );
		}
	}

	private static final class LocalClassLoader extends ClassLoader {
		private final Hashtable t;

		private LocalClassLoader(Hashtable t) {
			this.t = t;
		}

		public Class findClass(String classname) throws ClassNotFoundException {
			byte[] bytes = (byte[]) t.get(classname);
			if ( bytes != null ) {
				classname = classname.replace('/', '.');
				return defineClass(classname, bytes, 0, bytes.length);
			}
			return super.findClass(classname);
		}
	}

	class InputFile {
		public String luachunkname;
		public String srcfilename;
		public File infile;
		public File outdir;
		public String javapackage;

		public InputFile(File dir, File f, String javapackage) {
			this.infile = f;
			String subdir = javapackage!=null? javapackage.replace('.', '/'): null;
			String outdirpath = subdir!=null? destdir+"/"+subdir: destdir;
			this.javapackage = javapackage;
			this.srcfilename = (subdir!=null? subdir+"/": "")+infile.getName();
			this.luachunkname = (subdir!=null? subdir+"/": "")+infile.getName().substring( 0, infile.getName().lastIndexOf('.') );
			this.infile = f;
			this.outdir = new File(outdirpath);
		}
	}

	private void processFile( InputFile inf ) {
		inf.outdir.mkdirs();
		try {
			if ( verbose )
				System.out.println("chunk="+inf.luachunkname+" srcfile="+inf.srcfilename);

			// create the chunk
			FileInputStream fis = new FileInputStream( inf.infile );
			final Hashtable t = encoding != null?
					LuaJC.instance.compileAll( new InputStreamReader(fis, encoding), inf.luachunkname, inf.srcfilename, globals, genmain):
					LuaJC.instance.compileAll( fis, inf.luachunkname, inf.srcfilename, globals, genmain);
			fis.close();

			// write out the chunk
			for ( Enumeration e = t.keys(); e.hasMoreElements(); ) {
				String key = (String) e.nextElement();
				byte[] bytes = (byte[]) t.get(key);
				if ( key.indexOf('/')>=0 ) {
					String d = (destdir!=null? destdir+"/": "")+key.substring(0,key.lastIndexOf('/'));
					new File(d).mkdirs();
				}
				String destpath = (destdir!=null? destdir+"/": "") + key + ".class";
				if ( verbose )
					System.out.println( "  "+destpath +" ("+bytes.length+" bytes)");
				FileOutputStream fos = new FileOutputStream( destpath );
				fos.write( bytes );
				fos.close();
			}

			// try to load the files
			if ( loadclasses ) {
				ClassLoader loader = new LocalClassLoader(t);
				for ( Enumeration e = t.keys(); e.hasMoreElements(); ) {
					String classname = (String) e.nextElement();
					try {
						Class c = loader.loadClass(classname);
						Object o = c.newInstance();
						if ( verbose )
							System.out.println("    loaded "+classname+" as "+o );
					} catch ( Exception ex ) {
						System.out.flush();
						System.err.println("    failed to load "+classname+": "+ex );
						System.err.flush();
					}
				}
			}

		} catch ( Exception e ) {
			System.err.println("    failed to load "+inf.srcfilename+": "+e );
			e.printStackTrace( System.err );
			System.err.flush();
		}
	}
}
