/Users/paul/Documents/phlogo/core/Scope.cpp

/*
 *  Scope.cpp
 *
 *  Author: Paul Hamilton
 *      Date: 6 Jun 2011
 *
 */

#include "Scope.h"

#include "World.h"
#include "Exceptions.h"
#include "Thing.h"

using namespace std;

namespace phlogo {

Scope::Scope()
{
        _world = 0;
        _parent = 0;
}

Scope::Scope(World *world)
{
        _world = world;
        _parent = world->getScope();
        _world->setScope(this);
}

Scope::~Scope() {
        if (_parent)
                _world->setScope(_parent);
}

void Scope::setThing(const std::string &name, const std::string &value, bool local) { 

        pThing thing(new Thing());
        thing->set(value);
        setThing(name, thing, local);
}

void Scope::setThing(const std::string &name, pThing value, bool local) { 

        if (local)
                _things[name] = value;
        else {
                // we don't automatically set a var in this scope, lookup it up first 
                // and then if it's found, replace it's value where it's found.
                map<string, pThing >::iterator i = _things.find(name);
                if (i == _things.end()) {
                        Scope *p = _parent;
                        while (p) {
                                i = p->_things.find(name);
                                if (i != _things.end()) {
                                        p->_things[name] = value;
                                        return;
                                }
                                p = p->_parent;
                        }
                }
                _things[name] = value;
        }
}

pThing Scope::getThing(const string &name) 
{ 
        map<string, pThing >::iterator i = _things.find(name);
        if (i == _things.end()) {
                Scope *p = _parent;
                while (p) {
                        i = p->_things.find(name);
                        if (i != _things.end())
                                return i->second;
                        p = p->_parent;
                }
                BOOST_THROW_EXCEPTION( no_thing_exception() << errinfo_name(name) );
        }
        return i->second; 
}

void Scope::removeThing(const std::string &name) {
        map<string, pThing >::iterator i = _things.find(name);
    if (i != _things.end())
        _things.erase(i);
}

void Scope::removeThings() {
    
    _things.clear();
    
}

}