/**
 * @file tests/qss/models.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) 2013-2022 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 TESTS_QSS_MODELS_HPP
#define TESTS_QSS_MODELS_HPP

#include <artis-star/common/time/DoubleTime.hpp>
#include <artis-star/common/utils/Trace.hpp>

#include <artis-star/kernel/qss/Derivative.hpp>
#include <artis-star/kernel/qss/MultiDerivative.hpp>
#include <artis-star/kernel/dtss/Dynamics.hpp>

namespace artis {
namespace tests {
namespace qss {

class Constant : public artis::qss::Derivative<common::DoubleTime, Constant>
{
public:
  Constant(const std::string &name,
           const artis::pdevs::Context<common::DoubleTime,
                                       Constant,
                                       artis::common::NoParameters> &context)
      :
      artis::qss::Derivative<common::DoubleTime, Constant>(name,
                                                           context)
  {}

  ~Constant() override = default;

  double compute() const override
  { return 0.5; }
};

struct ParabolaParameters
{
  double alpha;
};

class Parabola
    : public artis::qss::Derivative<common::DoubleTime, Parabola, ParabolaParameters>
{
public:
  Parabola(const std::string &name,
           const artis::pdevs::Context<common::DoubleTime, Parabola, ParabolaParameters> &context)
      :
      artis::qss::Derivative<common::DoubleTime, Parabola, ParabolaParameters>(
          name,
          context), _alpha(context.parameters().alpha)
  {
    internal("X", &Parabola::_x);
  }

  ~Parabola() override = default;

  double compute() const override
  { return _alpha * _x; }

private:
  double _alpha;

  double _x;
};

struct PreyPredatorParameters
{
  double a;
  double b;
  double d;
  double e;
};

class Predator
    : public artis::qss::Derivative<common::DoubleTime, Predator, PreyPredatorParameters>
{
public:
  unsigned int IN_X;

  Predator(const std::string &name,
           const artis::pdevs::Context<common::DoubleTime,
                                       Predator,
                                       PreyPredatorParameters> &context)
      :
      artis::qss::Derivative<common::DoubleTime, Predator, PreyPredatorParameters>(
          name,
          context), _b(context.parameters().b), _d(context.parameters().d),
      _e(context.parameters().e)
  {
    internal("Y", &Predator::_y);
    IN_X = external("X", &Predator::_x);
  }

  ~Predator() override = default;

  double compute() const override
  { return _b * _d * _x * _y - _e * _y; }

private:
  // parameters
  double _b;
  double _d;
  double _e;

  // state
  double _x;
  double _y;
};

class Prey
    : public artis::qss::Derivative<common::DoubleTime, Prey, PreyPredatorParameters>
{
public:
  unsigned int IN_Y;

  Prey(const std::string &name,
       const artis::pdevs::Context<common::DoubleTime, Prey, PreyPredatorParameters> &context)
      :
      artis::qss::Derivative<common::DoubleTime, Prey, PreyPredatorParameters>(
          name,
          context), _a(context.parameters().a), _b(context.parameters().b)
  {
    internal("X", &Prey::_x);
    IN_Y = external("Y", &Prey::_y);
  }

  ~Prey() override = default;

  double compute() const override
  { return _a * _x - _b * _y * _x; }

private:
  // parameters
  double _a;
  double _b;

  // state
  double _x;
  double _y;
};

struct SmartGardenerParameters
{
  double threshold;
  double prey_proportion;
  double predator_proportion;
  double delay;
};

class SmartGardener
    : public artis::pdevs::Dynamics<common::DoubleTime, SmartGardener, SmartGardenerParameters>
{
public:
  enum inputs
  {
    IN_X, IN_Y
  };
  enum outputs
  {
    OUT_X, OUT_Y
  };

  SmartGardener(const std::string &name,
                const artis::pdevs::Context<common::DoubleTime,
                                            SmartGardener,
                                            SmartGardenerParameters> &context)
      :
      artis::pdevs::Dynamics<common::DoubleTime, SmartGardener, SmartGardenerParameters>(
          name, context),
      _threshold(context.parameters().threshold),
      _prey_proportion(context.parameters().prey_proportion),
      _predator_proportion(context.parameters().predator_proportion),
      _delay(context.parameters().delay)
  {
    input_ports({{IN_X, "in_x"},
                 {IN_Y, "in_y"}});
    output_ports({{OUT_X, "out_x"},
                  {OUT_Y, "out_y"}});
  }

  ~SmartGardener() override = default;

  void dint(const typename common::DoubleTime::type & /* t */) override
  {
    switch (_phase) {
    case INIT:_phase = IDLE;
      _sigma = _delay;
      break;
    case IDLE:
      if (_prey_amount > _threshold) {
        _phase = PEST;
      } else {
        _phase = IDLE;
        _sigma = _delay;
      }
      break;
    case PEST:_phase = IDLE;
      _sigma = _delay;
      break;
    }
  }

  void
  dext(const typename common::DoubleTime::type & /* t */,
       const typename common::DoubleTime::type &e,
       const common::event::Bag<common::DoubleTime> &bag) override
  {
    std::for_each(bag.begin(), bag.end(),
                  [this](const common::event::ExternalEvent<common::DoubleTime> &event) {
                    artis::qss::IntegratorData data;

                    event.data()(data);
                    if (event.on_port(IN_X)) {
                      _prey_amount = data.value;
                    } else if (event.on_port(IN_Y)) {
                      _predator_amount = data.value;
                    }
                  });
    _sigma -= e;
  }

  void
  start(const typename common::DoubleTime::type & /* t */) override
  { _phase = INIT; }

  typename common::DoubleTime::type
  ta(const typename common::DoubleTime::type & /* t */) const override
  {
    switch (_phase) {
    case INIT:return 0.0;
    case IDLE:return _sigma;
    case PEST:return 0.0;
    }
    return common::DoubleTime::infinity;
  }

  common::event::Bag<common::DoubleTime>
  lambda(const typename common::DoubleTime::type & /* t */) const override
  {
    common::event::Bag<common::DoubleTime> bag;

    if (_phase == PEST) {
      artis::qss::IntegratorData data = {_prey_amount * _prey_proportion};

      bag.push_back(common::event::ExternalEvent<common::DoubleTime>(OUT_X, data));
      data = {_predator_amount * _predator_proportion};
      bag.push_back(common::event::ExternalEvent<common::DoubleTime>(OUT_Y, data));
    }
    return bag;
  }

private:
  enum Phase
  {
    INIT, IDLE, PEST
  };

  // parameters
  double _threshold;
  double _prey_proportion;
  double _predator_proportion;
  double _delay;

  // state
  Phase _phase;
  common::DoubleTime::type _sigma;
  double _prey_amount;
  double _predator_amount;
};

struct DiscretePreyPredatorParameters
{
  artis::common::DoubleTime::type time_step;
  double init_value;
  double a;
  double b;
  double d;
  double e;
};

class DiscretePredator
    : public artis::dtss::Dynamics<artis::common::DoubleTime,
                                   DiscretePredator,
                                   DiscretePreyPredatorParameters>
{
public:
  enum inputs
  {
    RESET, IN_X, IN_Y
  };
  enum outputs
  {
    OUT
  };
  enum vars
  {
    VALUE
  };

  DiscretePredator(const std::string &name,
                   const artis::dtss::Context<artis::common::DoubleTime,
                                              DiscretePredator,
                                              DiscretePreyPredatorParameters> &context)
      :
      artis::dtss::Dynamics<artis::common::DoubleTime,
                            DiscretePredator,
                            DiscretePreyPredatorParameters>(
          name, context), _init_value(context.parameters().init_value),
      _b(context.parameters().b), _d(context.parameters().d),
      _e(context.parameters().e)
  {
    input_ports({{RESET, "reset"},
                 {IN_X, "in_x"},
                 {IN_Y, "in_y"}});
    output_ports({{OUT, "out"}});
    observables({{VALUE, "value"}});
  }

  ~DiscretePredator() override = default;

  void transition(const artis::common::event::Bag<artis::common::DoubleTime> &bag,
                  const artis::common::DoubleTime::type & /* t */) override
  {
    std::for_each(bag.begin(), bag.end(),
                  [this](const artis::common::event::ExternalEvent<artis::common::DoubleTime> &event) {
                    if (event.on_port(IN_X)) {
                      artis::qss::IntegratorData data;

                      event.data()(data);
                      _x = data.value;
                    } else if (event.on_port(RESET)) {
                      // TODO
                    }
                  });
    _y += (_b * _d * _x * _y - _e * _y) * time_step();
  }

  void start(const artis::common::DoubleTime::type & /* t */) override
  {
    _y = _init_value;
  }

  artis::common::event::Bag<artis::common::DoubleTime>
  lambda(const artis::common::DoubleTime::type & /* t */) const override
  {
    artis::common::event::Bag<artis::common::DoubleTime> msgs;
    artis::qss::IntegratorData data = {_y};

    msgs.push_back(
        artis::common::event::ExternalEvent<artis::common::DoubleTime>(OUT, data));
    return msgs;
  }

  artis::common::event::Value observe(const artis::common::DoubleTime::type & /* t */,
                               unsigned int index) const override
  {
    if (index == VALUE) {
      return (double) _y;
    }
    return artis::common::event::Value();
  }

private:
  // parameters
  double _init_value;
  double _b;
  double _d;
  double _e;

  // state
  double _x;
  double _y;
};

class PreyPredator
    : public artis::qss::MultiDerivative<common::DoubleTime, PreyPredator, PreyPredatorParameters>
{
public:
  PreyPredator(const std::string &name,
               const artis::pdevs::Context<common::DoubleTime, PreyPredator,
                                           PreyPredatorParameters> &context)
      :
      artis::qss::MultiDerivative<common::DoubleTime, PreyPredator, PreyPredatorParameters>(
          name, context),
      _a(context.parameters().a), _b(context.parameters().b),
      _d(context.parameters().d), _e(context.parameters().e)
  {
    internal("X", &PreyPredator::_x);
    internal("Y", &PreyPredator::_y);
  }

  ~PreyPredator() override = default;

  std::vector<double> compute() override
  {
    return {_a * _x - _b * _y * _x,
            _b * _d * _x * _y - _e * _y};
  }

private:
  // parameters
  double _a;
  double _b;
  double _d;
  double _e;

  // state
  double _x;
  double _y;
};

}
}
} // namespace artis tests qss

#endif