/*
 * AP_Controller.h
 * Copyright (C) James Goppert 2010 <james.goppert@gmail.com>
 *
 * This file 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 file 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 AP_Controller_H
#define AP_Controller_H

#include <inttypes.h>
#include "../GCS_MAVLink/GCS_MAVLink.h"
#include <math.h>

class AP_Var_group;

namespace apo {

class AP_HardwareAbstractionLayer;
class AP_Guide;
class AP_Navigator;
class Menu;

/// Controller class
class AP_Controller {
public:
	AP_Controller(AP_Navigator * nav, AP_Guide * guide,
			AP_HardwareAbstractionLayer * hal);
	virtual void update(const float & dt) = 0;
	virtual MAV_MODE getMode() = 0;
	void setAllRadioChannelsToNeutral();
	void setAllRadioChannelsManually();

protected:
	AP_Navigator * _nav;
	AP_Guide * _guide;
	AP_HardwareAbstractionLayer * _hal;
};

class AP_ControllerBlock {
public:
	AP_ControllerBlock(AP_Var_group * group, uint8_t groupStart,
			uint8_t groupLength) :
		_group(group), _groupStart(groupStart),
				_groupEnd(groupStart + groupLength) {
	}
	uint8_t getGroupEnd() {
		return _groupEnd;
	}
protected:
	AP_Var_group * _group; /// helps with parameter management
	uint8_t _groupStart;
	uint8_t _groupEnd;
};

class BlockLowPass: public AP_ControllerBlock {
public:
	BlockLowPass(AP_Var_group * group, uint8_t groupStart, float fCut,
			const prog_char_t * fCutLabel = NULL) :
		AP_ControllerBlock(group, groupStart, 1),
				_fCut(group, groupStart, fCut, fCutLabel ? : PSTR("fCut")),
				_y(0) {
	}
	float update(const float & input, const float & dt) {
		float RC = 1 / (2 * M_PI * _fCut); // low pass filter
		_y = _y + (input - _y) * (dt / (dt + RC));
		return _y;
	}
protected:
	AP_Float _fCut;
	float _y;
};

class BlockSaturation: public AP_ControllerBlock {
public:
	BlockSaturation(AP_Var_group * group, uint8_t groupStart, float yMax,
			const prog_char_t * yMaxLabel = NULL) :
		AP_ControllerBlock(group, groupStart, 1),
				_yMax(group, groupStart, yMax, yMaxLabel ? : PSTR("yMax")) {
	}
	float update(const float & input) {

		// pid sum
		float y = input;

		// saturation
		if (y > _yMax)
			y = _yMax;
		if (y < -_yMax)
			y = -_yMax;
		return y;
	}
protected:
	AP_Float _yMax; /// output saturation
};

class BlockDerivative {
public:
	BlockDerivative() :
		_lastInput(0), firstRun(true) {
	}
	float update(const float & input, const float & dt) {
		float derivative = (input - _lastInput) / dt;
		_lastInput = input;
		if (firstRun) {
			firstRun = false;
			return 0;
		} else
			return derivative;
	}
protected:
	float _lastInput; /// last input
	bool firstRun;
};

class BlockIntegral {
public:
	BlockIntegral() :
		_i(0) {
	}
	float update(const float & input, const float & dt) {
		_i += input * dt;
		return _i;
	}
protected:
	float _i; /// integral
};

class BlockP: public AP_ControllerBlock {
public:
	BlockP(AP_Var_group * group, uint8_t groupStart, float kP,
			const prog_char_t * kPLabel = NULL) :
		AP_ControllerBlock(group, groupStart, 1),
				_kP(group, groupStart, kP, kPLabel ? : PSTR("p")) {
	}

	float update(const float & input) {
		return _kP * input;
	}
protected:
	AP_Float _kP; /// proportional gain
};

class BlockI: public AP_ControllerBlock {
public:
	BlockI(AP_Var_group * group, uint8_t groupStart, float kI, float iMax,
			const prog_char_t * kILabel = NULL,
			const prog_char_t * iMaxLabel = NULL) :
		AP_ControllerBlock(group, groupStart, 2),
				_kI(group, groupStart, kI, kILabel ? : PSTR("i")),
				_blockSaturation(group, groupStart + 1, iMax, iMaxLabel ? : PSTR("iMax")),
				_eI(0) {
	}

	float update(const float & input, const float & dt) {
		// integral
		_eI += input * dt;
		_eI = _blockSaturation.update(_eI);
		return _kI * _eI;
	}
protected:
	AP_Float _kI; /// integral gain
	BlockSaturation _blockSaturation; /// integrator saturation
	float _eI; /// integral of input
};

class BlockD: public AP_ControllerBlock {
public:
	BlockD(AP_Var_group * group, uint8_t groupStart, float kD, uint8_t dFCut,
			const prog_char_t * kDLabel = NULL,
			const prog_char_t * dFCutLabel = NULL) :
				AP_ControllerBlock(group, groupStart, 2),
				_blockLowPass(group, groupStart, dFCut,
						dFCutLabel ? : PSTR("dFCut")),
				_kD(group, _blockLowPass.getGroupEnd(), kD,
						kDLabel ? : PSTR("d")), _eP(0) {
	}
	float update(const float & input, const float & dt) {
		// derivative with low pass
		float _eD = _blockLowPass.update((_eP - input) / dt, dt);
		// proportional, note must come after derivative
		// because derivatve uses _eP as previous value
		_eP = input;
		return _kD * _eD;
	}
protected:
	BlockLowPass _blockLowPass;
	AP_Float _kD; /// derivative gain
	float _eP; /// input
};

class BlockPID: public AP_ControllerBlock {
public:
	BlockPID(AP_Var_group * group, uint8_t groupStart, float kP, float kI,
			float kD, float iMax, float yMax, uint8_t dFcut) :
		AP_ControllerBlock(group, groupStart, 6),
				_blockP(group, groupStart, kP),
				_blockI(group, _blockP.getGroupEnd(), kI, iMax),
				_blockD(group, _blockI.getGroupEnd(), kD, dFcut),
				_blockSaturation(group, _blockD.getGroupEnd(), yMax) {
	}

	float update(const float & input, const float & dt) {
		return _blockSaturation.update(
				_blockP.update(input) + _blockI.update(input, dt)
						+ _blockD.update(input, dt));
	}
protected:
	BlockP _blockP;
	BlockI _blockI;
	BlockD _blockD;
	BlockSaturation _blockSaturation;
};

class BlockPI: public AP_ControllerBlock {
public:
	BlockPI(AP_Var_group * group, uint8_t groupStart, float kP, float kI,
			float iMax, float yMax) :
		AP_ControllerBlock(group, groupStart, 4),
				_blockP(group, groupStart, kP),
				_blockI(group, _blockP.getGroupEnd(), kI, iMax),
				_blockSaturation(group, _blockI.getGroupEnd(), yMax) {
	}

	float update(const float & input, const float & dt) {

		float y = _blockP.update(input) + _blockI.update(input, dt);
		return _blockSaturation.update(y);
	}
protected:
	BlockP _blockP;
	BlockI _blockI;
	BlockSaturation _blockSaturation;
};

class BlockPD: public AP_ControllerBlock {
public:
	BlockPD(AP_Var_group * group, uint8_t groupStart, float kP, float kI,
			float kD, float iMax, float yMax, uint8_t dFcut) :
		AP_ControllerBlock(group, groupStart, 4),
				_blockP(group, groupStart, kP),
				_blockD(group, _blockP.getGroupEnd(), kD, dFcut),
				_blockSaturation(group, _blockD.getGroupEnd(), yMax) {
	}

	float update(const float & input, const float & dt) {

		float y = _blockP.update(input) + _blockD.update(input, dt);
		return _blockSaturation.update(y);
	}
protected:
	BlockP _blockP;
	BlockD _blockD;
	BlockSaturation _blockSaturation;
};

/// PID with derivative feedback (ignores reference derivative)
class BlockPIDDfb: public AP_ControllerBlock {
public:
	BlockPIDDfb(AP_Var_group * group, uint8_t groupStart, float kP, float kI,
			float kD, float iMax, float yMax, float dFCut, 
			const prog_char_t * dFCutLabel = NULL,
			const prog_char_t * dLabel = NULL) :
		AP_ControllerBlock(group, groupStart, 5),
				_blockP(group, groupStart, kP),
				_blockI(group, _blockP.getGroupEnd(), kI, iMax),
				_blockSaturation(group, _blockI.getGroupEnd(), yMax),
				_blockLowPass(group, _blockSaturation.getGroupEnd(), dFCut, 
						dFCutLabel ? : PSTR("dFCut")),
				_kD(group, _blockLowPass.getGroupEnd(), kD, dLabel ? : PSTR("d"))
				{
	}
	float update(const float & input, const float & derivative,
			const float & dt) {
		
		float y = _blockP.update(input) + _blockI.update(input, dt) - _kD
				* _blockLowPass.update(derivative,dt);
		return _blockSaturation.update(y);
	}
protected:
	BlockP _blockP;
	BlockI _blockI;
	BlockSaturation _blockSaturation;
	BlockLowPass _blockLowPass;
	AP_Float _kD; /// derivative gain
};

} // apo

#endif // AP_Controller_H
// vim:ts=4:sw=4:expandtab