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