**** 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) 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) 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 java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import org.jruby.Ruby;
import org.jruby.RubyArray;
import org.jruby.RubyModule;
import org.jruby.RubyNil;
import org.jruby.RubyObject;
import org.jruby.embed.internal.BiVariableMap;
import org.jruby.runtime.builtin.IRubyObject;

Author:
yoko/**
 *
 * @author yoko
 */
public class Argv extends AbstractVariable {

    private static final String VALID_NAME = "ARGV";

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

    private Argv(RubyObject receiver, String name, Object... javaObjects) {
        super(receiver, name, false);
        assert javaObjects != null;
        javaObject = javaObjects[0];
        if (javaObject == null) {
            javaType = null;
        } else if (javaObjects.length > 1) {
            javaType = (Class) javaObjects[1];
        } else {
            javaType = javaObject.getClass();
        }
    }

    
A constructor used when ARGV is retrieved from Ruby.
Params:
receiver – a receiver object that this variable/constant is originally in. When
       the variable/constant is originated from Ruby, receiver may not be null.
name – the constant name
irubyObject – Ruby constant object/**
     * A constructor used when ARGV is retrieved from Ruby.
     *
     * @param receiver a receiver object that this variable/constant is originally in. When
     *        the variable/constant is originated from Ruby, receiver may not be null.
     * @param name the constant name
     * @param irubyObject Ruby constant object
     */
    Argv(RubyObject receiver, String name, IRubyObject irubyObject) {
        super(receiver, name, true, irubyObject);
    }

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

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

    
Injects ARGV values to a parsed Ruby script. This method is
invoked during EvalUnit#run() is executed.
Params:
runtime – is environment where a variable injection occurs
receiver – is the instance that will have variable injection./**
     * Injects ARGV values to a parsed Ruby script. This method is
     * invoked during EvalUnit#run() is executed.
     *
     * @param runtime is environment where a variable injection occurs
     * @param receiver is the instance that will have variable injection.
     */
    @Override
    public void inject() {
        final Ruby runtime = getRuntime();

        final RubyArray argv = RubyArray.newArray(runtime);
        if ( javaObject instanceof Collection ) {
            argv.addAll( (Collection) javaObject );
        }
        else if ( javaObject instanceof String[] ) {
            for ( String str : (String[]) javaObject ) argv.add(str);
        }
        this.rubyObject = argv; fromRuby = true;

        RubyModule rubyModule = getRubyClass(runtime);
        // SSS FIXME: With rubyclass stack gone, this needs a replacement
        if (rubyModule == null) rubyModule = null; // receiver.getRuntime().getCurrentContext().getRubyClass();

        if (rubyModule == null) return;

        rubyModule.storeConstant(name, argv);
        runtime.getConstantInvalidator(name).invalidate();
    }

    
Removes this object from BiVariableMap. Also, initialize this variable in top self. /**
     * Removes this object from {@link BiVariableMap}. Also, initialize
     * this variable in top self.
     */
    @Override
    public void remove() {
        this.javaObject = new ArrayList();
        inject();
    }

   
Retrieves ARGV from Ruby after the evaluation or method invocation.
Params:
runtime – Ruby runtime
receiver – receiver object returned when a script is evaluated.
vars – map to save retrieved constants./**
     * Retrieves ARGV from Ruby after the evaluation or method invocation.
     *
     * @param runtime Ruby runtime
     * @param receiver receiver object returned when a script is evaluated.
     * @param vars map to save retrieved constants.
     */
    public static void retrieve(final RubyObject receiver, final BiVariableMap vars) {
        if ( vars.isLazy() ) return;
        updateARGV(receiver, vars);
    }

    private static void updateARGV(final IRubyObject receiver, final BiVariableMap vars) {
        final String name = "ARGV";
        final RubyObject topSelf = getTopSelf(receiver);
        final IRubyObject argv = topSelf.getMetaClass().getConstant(name);
        if ( argv == null || (argv instanceof RubyNil) ) return;
        // ARGV constant should be only one
        if ( vars.containsKey(name) ) {
            BiVariable var = vars.getVariable(topSelf, name);
            var.setRubyObject(argv);
        }
        else {
            vars.update(name, new Argv(topSelf, name, argv));
        }
    }

    // ARGV appears to require special treatment, leaving javaType intact
    protected void updateRubyObject(final IRubyObject rubyObject) {
        if ( rubyObject == null ) return;
        this.rubyObject = rubyObject;
    }

    
Retrieves ARGV by key from Ruby runtime after the evaluation.
This method is used when eager retrieval is off.
Params:
receiver – receiver object returned when a script is evaluated.
vars – map to save retrieved instance variables.
key – instace varible name/**
     * Retrieves ARGV by key from Ruby runtime after the evaluation.
     * This method is used when eager retrieval is off.
     *
     * @param receiver receiver object returned when a script is evaluated.
     * @param vars map to save retrieved instance variables.
     * @param key instace varible name
     */
    public static void retrieveByKey(RubyObject receiver, BiVariableMap vars, String key) {
        assert key.equals("ARGV");
        updateARGV(receiver, vars);
    }

    @Override
    @SuppressWarnings("unchecked")
    public Object getJavaObject() {
        if ( rubyObject == null || ! fromRuby ) return javaObject;

        final RubyArray ary = (RubyArray) rubyObject;
        if (javaType == null) { // firstly retrieved from Ruby
            return javaObject = new ArrayList<String>(ary);
        }
        else if (javaType == String[].class) {
            String[] strArr = new String[ ary.size() ];
            for ( int i=0; i<ary.size(); i++ ) {
                strArr[i] = (String) ary.get(i);
            }
            return javaObject = strArr;
        }
        else if (javaObject instanceof List) {
            try {
                ((List) javaObject).clear();
                ((List) javaObject).addAll(ary);
            }
            catch (UnsupportedOperationException e) {
                // no op. no way to update.
            }
            return javaObject;
        }
        return null;
    }

}