/**
 * @file artis-star/common/observer/Observer.hpp
 * @author The ARTIS Development Team
 * See the AUTHORS or Authors.txt file
 */

/*
 * ARTIS - the multimodeling and simulation environment
 * This file is a part of the ARTIS environment
 *
 * Copyright (C) 2013-2019 ULCO http://www.univ-littoral.fr
 *
 * 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/>.
 */

#ifndef ARTIS_OBSERVER_OBSERVER_HPP
#define ARTIS_OBSERVER_OBSERVER_HPP

#include <artis-star/common/Model.hpp>
#include <artis-star/common/observer/View.hpp>

#include <vector>

namespace artis {
    namespace observer {

        template<typename Time>
        class Observer {
        public:
            typedef std::map<std::string, View<Time>*> Views;

            Observer(const common::Model<Time>* model)
                    :
                    _step(0),
                    _model(model) { }

            virtual ~Observer()
            {
                for (typename Views::iterator it = _views.begin(); it != _views.end();
                     ++it) {
                    delete it->second;
                }
            }

            void attachView(const std::string& name, View<Time>* view)
            {
                _views[name] = view;
                view->attachModel(_model);
            }

            Views* cloneViews() const
            {
                Views* v = new Views();

                for (typename Views::const_iterator it = _views.begin();
                     it != _views.end(); ++it) {
                    (*v)[it->first] = it->second->clone();
                }
                return v;
            }

            const View<Time>& view(const std::string& name) const
            {
                return *_views.find(name)->second;
            }

            const Views& views() const { return _views; }

            void init() { }

            void observe(double t, double next_t)
            {
                if (_step == 0) {
                    observe(t);
                } else {
                    double time = std::ceil(t / _step) * _step;

                    while (time < next_t) {
                        observe(time);
                        time += _step;
                    }
                }
            }

            void switch_to_timed_observer(double step)
            {

                assert(step > 0);

                _step = step;
            }

        private:
            void observe(double t)
            {
                for (typename Views::iterator it = _views.begin(); it != _views.end();
                     ++it) {
                    it->second->observe(t);
                }
            }

            double _step;
            const common::Model<Time>* _model;
            Views _views;
        };

    }
}

#endif