BEGIN LICENSE BLOCK *****
Version: EPL 2.0/GPL 2.0/LGPL 2.1
The contents of this file are subject to the Eclipse Public
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.eclipse.org/legal/epl-v20.html
Software distributed under the License is distributed on an "AS
IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
implied. See the License for the specific language governing
rights and limitations under the License.
Copyright (C) 2001 Chad Fowler 
Copyright (C) 2001 Alan Moore 
Copyright (C) 2001-2004 Jan Arne Petersen 
Copyright (C) 2002-2004 Anders Bengtsson 
Copyright (C) 2002-2005 Thomas E Enebo 
Copyright (C) 2004 Stefan Matthias Aust 
Copyright (C) 2005 Charles O Nutter 
Alternatively, the contents of this file may be used under the terms of
either of the GNU General Public License Version 2 or later (the "GPL"),
or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
in which case the provisions of the GPL or the LGPL are applicable instead
of those above. If you wish to allow use of your version of this file only
under the terms of either the GPL or the LGPL, and not to allow others to
use your version of this file under the terms of the EPL, indicate your
decision by deleting the provisions above and replace them with the notice
and other provisions required by the GPL or the LGPL. If you do not delete
the provisions above, a recipient may use your version of this file under
the terms of any one of the EPL, the GPL or the LGPL.
END LICENSE BLOCK /***** BEGIN LICENSE BLOCK *****
 * Version: EPL 2.0/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Eclipse Public
 * 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.eclipse.org/legal/epl-v20.html
 *
 * Software distributed under the License is distributed on an "AS
 * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 * implied. See the License for the specific language governing
 * rights and limitations under the License.
 *
 * Copyright (C) 2001 Chad Fowler <chadfowler@chadfowler.com>
 * Copyright (C) 2001 Alan Moore <alan_moore@gmx.net>
 * Copyright (C) 2001-2004 Jan Arne Petersen <jpetersen@uni-bonn.de>
 * Copyright (C) 2002-2004 Anders Bengtsson <ndrsbngtssn@yahoo.se>
 * Copyright (C) 2002-2005 Thomas E Enebo <enebo@acm.org>
 * Copyright (C) 2004 Stefan Matthias Aust <sma@3plus4.de>
 * Copyright (C) 2005 Charles O Nutter <headius@headius.com>
 * 
 * Alternatively, the contents of this file may be used under the terms of
 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the EPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the EPL, the GPL or the LGPL.
 ***** END LICENSE BLOCK *****/

package org.jruby;

import org.jruby.anno.JRubyClass;
import org.jruby.anno.JRubyMethod;
import org.jruby.parser.StaticScope;
import org.jruby.runtime.Binding;
import org.jruby.runtime.Block;
import org.jruby.runtime.ClassIndex;
import org.jruby.runtime.DynamicScope;
import org.jruby.runtime.ObjectAllocator;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.Visibility;
import org.jruby.runtime.builtin.IRubyObject;

Author:
 jpetersen/**
 * @author  jpetersen
 */
@JRubyClass(name="Binding")
public class RubyBinding extends RubyObject {
    private Binding binding;

    public RubyBinding(Ruby runtime, RubyClass rubyClass, Binding binding) {
        super(runtime, rubyClass);
        
        this.binding = binding;
    }

    private RubyBinding(Ruby runtime, RubyClass rubyClass) {
        super(runtime, rubyClass);
    }
    
    private static ObjectAllocator BINDING_ALLOCATOR = new ObjectAllocator() {
        @Override
        public IRubyObject allocate(Ruby runtime, RubyClass klass) {
            RubyBinding instance = new RubyBinding(runtime, klass);
            
            return instance;
        }
    };
    
    public static RubyClass createBindingClass(Ruby runtime) {
        RubyClass bindingClass = runtime.defineClass("Binding", runtime.getObject(), BINDING_ALLOCATOR);
        runtime.setBinding(bindingClass);

        bindingClass.setClassIndex(ClassIndex.BINDING);
        bindingClass.setReifiedClass(RubyBinding.class);
        
        bindingClass.defineAnnotatedMethods(RubyBinding.class);
        bindingClass.getSingletonClass().undefineMethod("new");
        
        return bindingClass;
    }

    public Binding getBinding() {
        return binding;
    }

    // Proc class

    public static RubyBinding newBinding(Ruby runtime, Binding binding) {
        return new RubyBinding(runtime, runtime.getBinding(), binding);
    }

    @Deprecated
    public static RubyBinding newBinding(Ruby runtime) {
        return newBinding(runtime, runtime.getCurrentContext().currentBinding());
    }

    @Deprecated
    public static RubyBinding newBinding(Ruby runtime, IRubyObject self) {
       return newBinding(runtime, runtime.getCurrentContext().currentBinding(self));
    }
    
    @JRubyMethod(name = "initialize", visibility = Visibility.PRIVATE)
    @Override
    public IRubyObject initialize(ThreadContext context) {
        binding = context.currentBinding();
        
        return this;
    }
    
    @JRubyMethod(name = "initialize_copy", required = 1, visibility = Visibility.PRIVATE)
    @Override
    public IRubyObject initialize_copy(IRubyObject other) {
        RubyBinding otherBinding = (RubyBinding)other;
        
        binding = otherBinding.binding.clone();
        
        return this;
    }

    // c: bind_eval
    @JRubyMethod(name = "eval", required=1, optional=2)
    public IRubyObject eval(ThreadContext context, IRubyObject[] args) {
        IRubyObject[] newArgs = new IRubyObject[args.length+1];
        newArgs[0] = args[0]; // eval string
        newArgs[1] = this; // binding
        if(args.length>1) {
            newArgs[2] = args[1]; // file
            if(args.length>2) {
                newArgs[3] = args[2]; // line
            }
        }

        return RubyKernel.eval(context, this, newArgs, Block.NULL_BLOCK);
    }

    @JRubyMethod(name = "local_variable_defined?")
    public IRubyObject local_variable_defined_p(ThreadContext context, IRubyObject symbol) {
        return context.runtime.newBoolean(binding.getEvalScope(context.runtime).getStaticScope().isDefined(symbol.asJavaString()) != -1);
    }

    @JRubyMethod
    public IRubyObject local_variable_get(ThreadContext context, IRubyObject symbol) {
        String name = symbol.asJavaString().intern();
        DynamicScope evalScope = binding.getEvalScope(context.runtime);
        int slot = evalScope.getStaticScope().isDefined(name);

        if (slot == -1) throw context.runtime.newNameError("local variable `" + name +  "' not defined for " + inspect(), name);

        return evalScope.getValueOrNil(slot & 0xffff, slot >> 16, context.nil);
    }

    @JRubyMethod
    public IRubyObject local_variable_set(ThreadContext context, IRubyObject symbol, IRubyObject value) {
        String name = symbol.asJavaString().intern();
        DynamicScope evalScope = binding.getEvalScope(context.runtime);
        int slot = evalScope.getStaticScope().isDefined(name);

        if (slot == -1) { // Yay! New variable associated with this binding
            slot = evalScope.getStaticScope().addVariable(name.intern());
            evalScope.growIfNeeded();
        }

        return evalScope.setValue(slot & 0xffff, value, slot >> 16);
    }

    @JRubyMethod
    public IRubyObject local_variables(ThreadContext context) {
        Ruby runtime = context.runtime;

        return binding.getEvalScope(runtime).getStaticScope().getLocalVariables(runtime);
    }

    @JRubyMethod(name = "receiver")
    public IRubyObject receiver(ThreadContext context) {
        return binding.getSelf();
    }
}