// $Id$
/*
 * WorldEdit
 * Copyright (C) 2010 sk89q <http://www.sk89q.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

package com.sk89q.worldedit.scripting.java;

import java.io.*;
import javax.script.*;
import org.mozilla.javascript.*;
import com.sk89q.worldedit.scripting.RhinoContextFactory;

public class RhinoScriptEngine extends AbstractScriptEngine {
    private ScriptEngineFactory factory;
    private Context cx;

    public RhinoScriptEngine() {
        RhinoContextFactory factory = new RhinoContextFactory(3000);
        factory.enterContext();
    }

    public Bindings createBindings() {
        return new SimpleBindings();
    }

    @Override
    public Object eval(String script, ScriptContext context)
            throws ScriptException {
        
        Scriptable scope = setupScope(cx, context);
        
        String filename = (filename = (String)get(ScriptEngine.FILENAME)) == null
                ? "<unknown>" : filename;
        
        try {
            return cx.evaluateString(scope, script, filename, 1, null);
        } catch (RhinoException e) {
            String msg;
            int line = (line = e.lineNumber()) == 0 ? -1 : line;
            
            if (e instanceof JavaScriptException) {
                msg = String.valueOf(((JavaScriptException)e).getValue());
            } else {
                msg = e.getMessage();
            }
            
            ScriptException scriptException =
                new ScriptException(msg, e.sourceName(), line);
            scriptException.initCause(e);
            
            throw scriptException;
        } finally {
            Context.exit();
        }
    }

    @Override
    public Object eval(Reader reader, ScriptContext context)
            throws ScriptException {
        
        Scriptable scope = setupScope(cx, context);
        
        String filename = (filename = (String)get(ScriptEngine.FILENAME)) == null
                ? "<unknown>" : filename;
        
        try {
            return cx.evaluateReader(scope, reader, filename, 1, null);
        } catch (RhinoException e) {
            String msg;
            int line = (line = e.lineNumber()) == 0 ? -1 : line;
            
            if (e instanceof JavaScriptException) {
                msg = String.valueOf(((JavaScriptException)e).getValue());
            } else {
                msg = e.getMessage();
            }
            
            ScriptException scriptException =
                new ScriptException(msg, e.sourceName(), line);
            scriptException.initCause(e);
            
            throw scriptException;
        } catch (IOException e) {
            throw new ScriptException(e);
        } finally {
            Context.exit();
        }
    }

    @Override
    public ScriptEngineFactory getFactory() {
        if (factory != null) {
            return factory;
        } else {
            return new RhinoScriptEngineFactory();
        }
    }
    
    private Scriptable setupScope(Context cx, ScriptContext context) {
        ScriptableObject scriptable = new ImporterTopLevel(cx);
        Scriptable scope = cx.initStandardObjects(scriptable);
        //ScriptableObject.putProperty(scope, "argv", Context.javaToJS(args, scope));
        return scope;
    }
}