/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

package org.apache.myfaces.extensions.scripting.core.engine.compiler;

import org.apache.myfaces.extensions.scripting.core.api.Configuration;
import org.apache.myfaces.extensions.scripting.core.api.WeavingContext;
import org.apache.myfaces.extensions.scripting.core.common.util.ClassLoaderUtils;
import org.apache.myfaces.extensions.scripting.core.common.util.FileUtils;
import org.apache.myfaces.extensions.scripting.core.engine.api.CompilationException;
import org.apache.myfaces.extensions.scripting.core.engine.api.CompilationResult;

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.io.File;
import java.util.List;

import static org.apache.myfaces.extensions.scripting.core.api.ScriptingConst.ENGINETYPE_JSF_JRUBY;
import static org.apache.myfaces.extensions.scripting.core.engine.api.CompilerConst.JRUBY_WILDARD;

/**
 * @author Werner Punz (latest modification by $Author$)
 * @version $Revision$ $Date$
 *          <p/>
 *          A compiler for jruby which uses ruby and the standard JSR 233
 *          for compiling classes into java classes
 */

public class JRubyCompiler implements org.apache.myfaces.extensions.scripting.core.engine.api.Compiler
{

    private static final String ENGINE_JRUBY = "jruby";

    @Override
    public CompilationResult compile(File sourcePath, File targetPath, ClassLoader classLoader)
    {
        targetPath.mkdirs();
        String sources = getSourceFiles();
        return compile(sourcePath, targetPath, sources);
    }

    public CompilationResult compile(File sourcePath, File targetPath, String sources)
    {
        targetPath.mkdirs();
        if(targetPath.isDirectory() && targetPath.exists()){
            System.out.println("targetpath is there");
        }
        String classPath = ClassLoaderUtils.buildClasspath(ClassLoaderUtils.getDefaultClassLoader());

        StringBuilder commandString = new StringBuilder();
        commandString.append("require 'jruby/jrubyc'\n");
        commandString.append("options = Array.new \n");
        commandString.append("options << '-d" + sourcePath.getAbsolutePath() + "'\n");
        commandString.append("options<< '--javac' \n");
        commandString.append("options<< '-t" + targetPath.getAbsolutePath() + "'\n");
        commandString.append("options<< '-c" + classPath + " '\n");
        commandString.append("options<< '" + sources + " '\n");
        commandString.append("$status = JRuby::Compiler::compile_argv(options) \n");
        ScriptEngineManager manager = new ScriptEngineManager();
        ScriptEngine engine = manager.getEngineByName(ENGINE_JRUBY);
        try
        {
            engine.eval(commandString.toString());
            String status = (String) engine.get("status");
            if(status.equals("0")) {
                return null;
            }
            //TODO parse the result and return a meaningful compilationresult
            return null;
        }
        catch (ScriptException e)
        {
            e.printStackTrace();
        }

        return null;
    }

    private String getSourceFiles()
    {
        WeavingContext context = WeavingContext.getInstance();
        Configuration configuration = context.getConfiguration();
        List<File> sourceFiles = FileUtils.fetchSourceFiles(configuration.getWhitelistedSourceDirs
                (ENGINETYPE_JSF_JRUBY), JRUBY_WILDARD);
        StringBuilder sources = new StringBuilder(sourceFiles.size() * 30);
        for (File sourceFile : sourceFiles)
        {
            sources.append(sourceFile.getAbsolutePath());
            sources.append(" ");
        }
        return sources.toString();
    }

    public static void main(String... argv)
    {
        ScriptEngineManager manager = new ScriptEngineManager();
        ScriptEngine engine = manager.getEngineByName(ENGINE_JRUBY);
        try
        {
            engine.eval("require 'jruby/jrubyc'\n" +
                    "$status = 'hello world' #JRuby::Compiler::compile_argv(ARGV)");

            Object status = engine.get("status");
            System.out.println(status.toString());
        }
        catch (ScriptException e)
        {
            e.printStackTrace();  //To change body of catch statement use File | Settings | File Templates.
        }

    }

}