**** 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) 2009-2011 Yoko Harada 
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) 2009-2011 Yoko Harada <yokolet@gmail.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.embed.variable;

import org.jruby.RubyObject;
import org.jruby.embed.internal.BiVariableMap;
import org.jruby.runtime.DynamicScope;
import org.jruby.runtime.ThreadContext;
import org.jruby.runtime.builtin.IRubyObject;
import org.jruby.runtime.scope.ManyVarsDynamicScope;

An implementation of BiVariable for a persistent local variable. This type of
a local variable survives over multiple evaluation.
Author:
Yoko Harada /**
 * An implementation of BiVariable for a persistent local variable. This type of
 * a local variable survives over multiple evaluation.
 *
 * @author Yoko Harada <yokolet@gmail.com>
 */
public class PersistentLocalVariable extends AbstractVariable {

    private static final String VALID_NAME = "([a-z]|_)([a-zA-Z]|_|\\d)*";

    
Returns an instance of this class. This factory method is used when a persistent local variable is put in BiVariableMap. 
Params:
runtime – Ruby runtime
name – a variable name
javaObject – Java object that should be assigned to.
Returns:
the instance of PersistentLocalVariable/**
     * Returns an instance of this class. This factory method is used when a
     * persistent local variable is put in {@link BiVariableMap}.
     *
     * @param runtime Ruby runtime
     * @param name a variable name
     * @param javaObject Java object that should be assigned to.
     * @return the instance of PersistentLocalVariable
     */
    public static BiVariable getInstance(RubyObject receiver, String name, Object... javaObject) {
        if (name.matches(VALID_NAME)) {
            return new PersistentLocalVariable(receiver, name, javaObject);
        }
        return null;
    }

    private PersistentLocalVariable(RubyObject receiver, String name, Object... javaObjects) {
        super(receiver, name, false);
        updateByJavaObject(receiver.getRuntime(), javaObjects);
    }

    
A constructor used when persistent local variables are retrieved from Ruby.
Params:
name – the persistent local variable name
irubyObject – Ruby local object/**
     * A constructor used when persistent local variables are retrieved from Ruby.
     *
     * @param name the persistent local variable name
     * @param irubyObject Ruby local object
     */
    PersistentLocalVariable(RubyObject origin, String name, IRubyObject irubyObject) {
        super(origin, name, true, irubyObject);
    }

    
Returns enum type of this variable defined in BiVariable. 
Returns:
this enum type, BiVariable.Type.LocalVariable./**
     * Returns enum type of this variable defined in {@link BiVariable}.
     *
     * @return this enum type, BiVariable.Type.LocalVariable.
     */
    @Override
    public Type getType() {
        return Type.LocalVariable;
    }

    
Returns true if the given name is a decent Ruby local variable. Unless
returns false.
Params:
name – is a name to be checked.
Returns:
true if the given name is of a Ruby local variable./**
     * Returns true if the given name is a decent Ruby local variable. Unless
     * returns false.
     *
     * @param name is a name to be checked.
     * @return true if the given name is of a Ruby local variable.
     */
    public static boolean isValidName(Object name) {
        return isValidName(VALID_NAME, name);
    }

    
Retrieves local variables from Ruby after the evaluation. This retrieval doesn't
depend on eager option. Local variables are always retrieved eagerly.
Params:
runtime – Ruby runtime
receiver – receiver object returned when a script is evaluated.
vars – map to save retrieved local variables./**
     * Retrieves local variables from Ruby after the evaluation. This retrieval doesn't
     * depend on eager option. Local variables are always retrieved eagerly.
     *
     * @param runtime Ruby runtime
     * @param receiver receiver object returned when a script is evaluated.
     * @param vars map to save retrieved local variables.
     */
    public static void retrieve(RubyObject receiver, BiVariableMap vars) {
        ManyVarsDynamicScope scope =
            (ManyVarsDynamicScope) receiver.getRuntime().getCurrentContext().getCurrentScope();
        if (scope == null) {
            return;
        }
        String[] names = scope.getAllNamesInScope();
        IRubyObject[] values = scope.getValues();
        if (names == null || values == null || names.length == 0 || values.length == 0) {
            return;
        }
        // Local variable is always saved as a top level variable.
        for (int i=0; i<names.length; i++) {
            BiVariable var;
            final RubyObject topSelf = getTopSelf(receiver);
            if ( ( var = vars.getVariable(topSelf, names[i]) ) != null
                && topSelf == var.getReceiver() ) {
                var.setRubyObject( values[i] );
            } else {
                var = new PersistentLocalVariable(topSelf, names[i], values[i]);
                vars.update( names[i], var );
            }
        }
    }

    
Injects a local variable value to a parsed Ruby script. This method is
invoked during EvalUnit#run() is executed.
/**
     * Injects a local variable value to a parsed Ruby script. This method is
     * invoked during EvalUnit#run() is executed.
     */
    @Override
    public void inject() {
        //done in JRubyVariableMap.inject()
    }

    
Attempts to remove this variable from top self or receiver.
/**
     * Attempts to remove this variable from top self or receiver.
     *
     */
    @Override
    public void remove() {
        // FIXME: Code originally here did not appear to actually do anything, so it was removed.
    }
}