/* Node-type for signal generation.
 *
 * Author: Steffen Vogel <post@steffenvogel.de>
 * SPDX-FileCopyrightText: 2014-2023 Institute for Automation of Complex Power Systems, RWTH Aachen University
 * SPDX-License-Identifier: Apache-2.0
 */

#pragma once

#include <villas/node.hpp>
#include <villas/task.hpp>
#include <villas/timing.hpp>

namespace villas {
namespace node {

// Forward declarations
struct Sample;

class SignalNodeSignal {

public:
  enum class Type {
    RANDOM,
    SINE,
    SQUARE,
    TRIANGLE,
    RAMP,
    COUNTER,
    CONSTANT,
    PULSE,
    MIXED
  };

  enum Type type;

  double frequency; // Frequency of the generated signals.
  double amplitude; // Amplitude of the generated signals.
  double stddev; // Standard deviation of random signals (normal distributed).
  double offset; // A constant bias.
  double
      pulse_width; // Width of a pulse with respect to the rate (duration = pulse_width/rate)
  double pulse_low;  // Amplitude when pulse signal is off
  double pulse_high; // Amplitude when pulse signal is on
  double phase;      // Phase (rad) offset with respect to program start
  double
      last; // The values from the previous period which are required for random walk.

public:
  SignalNodeSignal(json_t *json);

  int parse(json_t *json);

  static enum Type lookupType(const std::string &type);

  static std::string typeToString(enum Type type);

  void start();

  void read(unsigned c, double t, double rate, SignalData *d);

  Signal::Ptr toSignal(Signal::Ptr tpl) const;
};

class SignalNode : public Node {

protected:
  std::vector<SignalNodeSignal> signals;

  struct Task task; // Timer for periodic events.
  int rt;           // Real-time mode?

  double rate; // Sampling rate.
  bool
      monitor_missed; // Boolean, if set, node counts missed steps and warns user.
  int limit; // The number of values which should be generated by this node. <0 for infinite.

  struct timespec started; // Point in time when this node was started.
  unsigned missed_steps;   // Total number of missed steps.

  virtual int _read(struct Sample *smps[], unsigned cnt);

public:
  SignalNode(const uuid_t &id = {}, const std::string &name = "");

  virtual const std::string &getDetails();

  virtual int parse(json_t *json);

  virtual int start();

  virtual int stop();

  virtual int prepare();

  virtual std::vector<int> getPollFDs();
};

} // namespace node
} // namespace villas