///
/// Copyright (C) 2015, 2016 "IoT.bzh"
/// Author "Romain Forlot" <romain.forlot@iot.bzh>
///
/// Licensed under the Apache License, Version 2.0 (the "License");
/// you may not use this file except in compliance with the License.
/// You may obtain a copy of the License at
///
///	 http://www.apache.org/licenses/LICENSE-2.0
///
/// Unless required by applicable law or agreed to in writing, software
/// distributed under the License is distributed on an "AS IS" BASIS,
/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
/// See the License for the specific language governing permissions and
/// limitations under the License.
///

#pragma once

#include <map>
#include <mutex>
#include <vector>
#include <string>
#include <memory>

#include "openxc.pb.h"
#include "can-message-definition.hpp"
#include "../utils/timer.hpp"
#include "../utils/socketcan-bcm.hpp"
#include "can-message.hpp"
#include "../diagnostic/diagnostic-message.hpp"

#define MESSAGE_SET_ID 0

class can_signal_t;
///
/// @brief The type signature for a CAN signal decoder.
///
/// A signal_decoder transforms a raw floating point CAN signal into a number,
/// string or boolean.
///
/// @param[in] signal - The CAN signal that we are decoding.
/// @param[in] signalCount - The length of the signals array.
/// @param[in] value - The CAN signal parsed from the message as a raw floating point
///	value.
/// @param[out] send - An output parameter. If the decoding failed or the CAN signal should
///	not send for some other reason, this should be flipped to false.
///
/// @return a decoded value in an openxc_DynamicField struct.
///
typedef openxc_DynamicField (*signal_decoder)(can_signal_t& signal, float value, bool* send);

///
/// @brief: The type signature for a CAN signal encoder.
///
/// A signal_encoder transforms a number, string or boolean into a raw floating
/// point value that fits in the CAN signal.
///
/// @param[in] signal - The CAN signal to encode.
/// @param[in] value - The dynamic field to encode.
/// @param[out] send - An output parameter. If the encoding failed or the CAN signal should
/// not be encoded for some other reason, this will be flipped to false.
///
typedef uint64_t (*signal_encoder)(can_signal_t* signal,
		openxc_DynamicField* value, bool* send);

class can_signal_t
{
private:
	can_message_definition_t* parent_; /*!< parent_ - pointer to the parent message definition holding this signal*/
	std::string generic_name_; /*!< generic_name_ - The name of the signal to be output.*/
	static std::string prefix_; /*!< prefix_ - generic_name_ will be prefixed with it. It has to reflect the used protocol.
						  * which make easier to sort message when the come in.*/
	uint8_t bit_position_; /*!< bitPosition_ - The starting bit of the signal in its CAN message (assuming
										*	non-inverted bit numbering, i.e. the most significant bit of
										*	each byte is 0) */
	uint8_t bit_size_; /*!< bit_size_ - The width of the bit field in the CAN message. */
	float factor_; /*!< factor_ - The final value will be multiplied by this factor. Use 1 if you
							*	don't need a factor. */
	float offset_; /*!< offset_ - The final value will be added to this offset. Use 0 if you
							*	don't need an offset. */
	float min_value_; /*!< min_value_ - The minimum value for the processed signal.*/
	float max_value_; /*!< max_value_ - The maximum value for the processed signal. */
	frequency_clock_t frequency_; /*!< frequency_ - A frequency_clock_t struct to control the maximum frequency to
								*	process and send this signal. To process every value, set the
								*	clock's frequency to 0. */
	bool send_same_; /*!< send_same_ - If true, will re-send even if the value hasn't changed.*/
	bool force_send_changed_; /*!< force_send_changed_ - If true, regardless of the frequency, it will send the
							   * value if it has changed. */
	std::map<uint8_t, std::string> states_; /*!< states_ - A map of CAN signal state describing the mapping
										 * between numerical and string values for valid states. */
	bool writable_; /*!< writable - True if the signal is allowed to be written from the USB host
					 *	back to CAN. Defaults to false.*/
	signal_decoder decoder_; /*!< decoder_ - An optional function to decode a signal from the bus to a human
							 * readable value. If NULL, the default numerical decoder is used. */
	signal_encoder encoder_; /*!< encoder_ - An optional function to encode a signal value to be written to
							 * CAN into a byte array. If NULL, the default numerical encoder
							 * is used. */
	bool received_; /*!< received_ - True if this signal has ever been received.*/
	float last_value_; /*!< lastValue_ - The last received value of the signal. If 'received' is false,
						*	this value is undefined. */

public:
	can_signal_t(
		std::string generic_name,
		uint8_t bit_position,
		uint8_t bit_size,
		float factor,
		float offset,
		float min_value,
		float max_value,
		frequency_clock_t frequency,
		bool send_same,
		bool force_send_changed,
		std::map<uint8_t, std::string> states,
		bool writable,
		signal_decoder decoder,
		signal_encoder encoder,
		bool received);

	can_message_definition_t* get_message() const;
	const std::string get_generic_name() const;
	const std::string get_name() const;
	const std::string get_prefix() const;
	uint8_t get_bit_position() const;
	uint8_t get_bit_size() const;
	float get_factor() const;
	float get_offset() const;
	float get_min_value() const;
	float get_max_value() const;
	frequency_clock_t& get_frequency();
	bool get_send_same() const;
	bool get_force_send_changed() const;
	const std::map<uint8_t, std::string>& get_states() const;
	const std::string get_states(uint8_t value);
	uint64_t get_states(const std::string& value) const;
	size_t get_state_count() const;
	bool get_writable() const;
	signal_decoder& get_decoder();
	signal_encoder& get_encoder();
	bool get_received() const;
	float get_last_value() const;
	std::pair<float, uint64_t> get_last_value_with_timestamp() const;

	void set_parent(can_message_definition_t* parent);
	void set_prefix(std::string val);
	void set_received(bool r);
	void set_last_value(float val);
	void set_timestamp(uint64_t timestamp);
};