/*
	AP_MotorsHeli.cpp - ArduCopter motors library
	Code by RandyMackay. DIYDrones.com

	This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.
*/

#include "AP_MotorsHeli.h"

const AP_Param::GroupInfo AP_MotorsHeli::var_info[] PROGMEM = {
	
	
	// @Param: SV1_POS
	// @DisplayName: Servo 1 Position
	// @Description: This is the angular location of swash servo #1.
	// @Range: -180 180
	// @Units: Degrees
	// @User: Standard
	// @Increment: 1
	AP_GROUPINFO("SV1_POS",	1,	AP_MotorsHeli,	servo1_pos, -60),
	
	// @Param: SV2_POS
	// @DisplayName: Servo 2 Position
	// @Description: This is the angular location of swash servo #2.
	// @Range: -180 180
	// @Units: Degrees
	// @User: Standard
	// @Increment: 1
	AP_GROUPINFO("SV2_POS",	2,	AP_MotorsHeli,	servo2_pos,  60),
	
	// @Param: SV3_POS
	// @DisplayName: Servo 3 Position
	// @Description: This is the angular location of swash servo #3.
	// @Range: -180 180
	// @Units: Degrees
	// @User: Standard
	// @Increment: 1
	AP_GROUPINFO("SV3_POS",	3,	AP_MotorsHeli,	servo3_pos,  180),
	
	// @Param: ROL_MAX
	// @DisplayName: Maximum Roll Angle
	// @Description: This is the maximum allowable roll of the swash plate.
	// @Range: 0 18000
	// @Units: Degrees
	// @Increment: 1
	// @User: Advanced
	AP_GROUPINFO("ROL_MAX",	4,	AP_MotorsHeli,	roll_max,    4500),
	
	// @Param: PIT_MAX
	// @DisplayName: Maximum Pitch Angle
	// @Description: This is the maximum allowable pitch of the swash plate.
	// @Range: 0 18000
	// @Units: Degrees
	// @Increment: 1
	// @User: Advanced
	AP_GROUPINFO("PIT_MAX",	5,	AP_MotorsHeli,	pitch_max,   4500),
	
	// @Param: COL_MIN
	// @DisplayName: Collective Pitch Minimum
	// @Description: This controls the lowest possible servo position for the swashplate.
	// @Range: 1000 2000
	// @Units: PWM
	// @Increment: 1
	// @User: Standard
	AP_GROUPINFO("COL_MIN",	6,	AP_MotorsHeli,	collective_min, 1250),
	
	// @Param: COL_MAX
	// @DisplayName: Collective Pitch Maximum
	// @Description: This controls the highest possible servo position for the swashplate.
	// @Range: 1000 2000
	// @Units: PWM
	// @Increment: 1
	// @User: Standard
	AP_GROUPINFO("COL_MAX",	7,	AP_MotorsHeli,	collective_max, 1750),
	
	// @Param: COL_MID
	// @DisplayName: Collective Pitch Mid-Point
	// @Description: This is the swash servo position corresponding to zero collective pitch (or zero lift for Assymetrical blades).
	// @Range: 1000 2000
	// @Units: PWM
	// @Increment: 1
	// @User: Standard
	AP_GROUPINFO("COL_MID",	8,	AP_MotorsHeli,	collective_mid, 1500),
	
	// @Param: GYR_ENABLE
	// @DisplayName: External Gyro Enabled
	// @Description: Setting this to Enabled(1) will enable an external rudder gyro control which means outputting a gain on channel 7 and using a simpler heading control algorithm. Setting this to Disabled(0) will disable the external gyro gain on channel 7 and revert to a more complex yaw control algorithm.
	// @Values: 0:Disabled,1:Enabled
	// @User: Standard
	AP_GROUPINFO("GYR_ENABLE",	9,	AP_MotorsHeli,	ext_gyro_enabled, 0),
	
	// @Param: SWASH_TYPE
	// @DisplayName: Swash Plate Type
	// @Description: Setting this to 0 will configure for a 3-servo CCPM. Setting this to 1 will configure for mechanically mixed "H1".
	// @User: Standard
	AP_GROUPINFO("SWASH_TYPE",	10,	AP_MotorsHeli,	swash_type, AP_MOTORS_HELI_SWASH_CCPM),				
	
	// @Param: GYR_GAIN
	// @DisplayName: External Gyro Gain
	// @Description: This is the PWM which is passed to the external gyro when external gyro is enabled.
	// @Range: 1000 2000
	// @Units: PWM
	// @Increment: 1
	// @User: Standard
	AP_GROUPINFO("GYR_GAIN",	11,	AP_MotorsHeli,	ext_gyro_gain, 1350),
		
	// @Param: SV_MAN
	// @DisplayName: Manual Servo Mode
	// @Description: Setting this to Enabled(1) will pass radio inputs directly to servos. Setting this to Disabled(0) will enable Arducopter control of servos.  This is only meant to be used by the Mission Planner using swash plate set-up.
	// @Values: 0:Disabled,1:Enabled
	// @User: Standard	
	AP_GROUPINFO("SV_MAN",		12,	AP_MotorsHeli,	servo_manual,  0),
	
	// @Param: PHANG
	// @DisplayName: Swashplate Phase Angle Compensation
	// @Description: This corrects for phase angle errors of the helicopter main rotor head.  For example if pitching the swash forward also induces a roll, that effect can be offset with this parameter.
	// @Range: -90 90
	// @Units: Degrees
	// @User: Advanced
	// @Increment: 1
	AP_GROUPINFO("PHANG",		13,	AP_MotorsHeli,	phase_angle,   0),				
	
	// @Param: COLYAW
	// @DisplayName: Collective-Yaw Mixing
	// @Description: This is a feed-forward compensation to automatically add rudder input when collective pitch is increased.
	// @Range: 0 5
	AP_GROUPINFO("COLYAW",		14,	AP_MotorsHeli,	collective_yaw_effect, 0),	
	
	// @Param: GOV_SETPOINT
	// @DisplayName: External Motor Governor Setpoint
	// @Description: This is the PWM which is passed to the external motor governor when external governor is enabled.
	// @Range: 1000 2000
	// @Units: PWM
	// @Increment: 10
	// @User: Standard
	AP_GROUPINFO("GOV_SETPOINT", 15, AP_MotorsHeli, ext_gov_setpoint, 1500),
	
    AP_GROUPEND
};

// init
void AP_MotorsHeli::Init()
{
	// set update rate
	set_update_rate(_speed_hz);
}

// set update rate to motors - a value in hertz or AP_MOTORS_SPEED_INSTANT_PWM for instant pwm
void AP_MotorsHeli::set_update_rate( uint16_t speed_hz )
{
	// record requested speed
	_speed_hz = speed_hz;

	// setup fast channels
	if( _speed_hz != AP_MOTORS_SPEED_INSTANT_PWM ) {
		_rc->SetFastOutputChannels(_BV(_motor_to_channel_map[AP_MOTORS_MOT_1]) | _BV(_motor_to_channel_map[AP_MOTORS_MOT_2]) | _BV(_motor_to_channel_map[AP_MOTORS_MOT_3]) | _BV(_motor_to_channel_map[AP_MOTORS_MOT_4]), _speed_hz);
	}
}

	// enable - starts allowing signals to be sent to motors
void AP_MotorsHeli::enable()
{
	// enable output channels
	_rc->enable_out(_motor_to_channel_map[AP_MOTORS_MOT_1]);	// swash servo 1
	_rc->enable_out(_motor_to_channel_map[AP_MOTORS_MOT_2]);	// swash servo 2
	_rc->enable_out(_motor_to_channel_map[AP_MOTORS_MOT_3]);	// swash servo 3
	_rc->enable_out(_motor_to_channel_map[AP_MOTORS_MOT_4]);	// yaw
	_rc->enable_out(AP_MOTORS_HELI_EXT_GYRO);	// for external gyro
	_rc->enable_out(AP_MOTORS_HELI_EXT_ESC);	// for external ESC
}

// output_min - sends minimum values out to the motors
void AP_MotorsHeli::output_min()
{
	// move swash to mid
	move_swash(0,0,500,0);
}

// output_armed - sends commands to the motors
void AP_MotorsHeli::output_armed()
{
    // if manual override (i.e. when setting up swash), pass pilot commands straight through to swash
    if( servo_manual == 1 ) {
		_rc_roll->servo_out = _rc_roll->control_in;
		_rc_pitch->servo_out = _rc_pitch->control_in;
		_rc_throttle->servo_out = _rc_throttle->control_in;
		_rc_yaw->servo_out = _rc_yaw->control_in;
	}

    //static int counter = 0;
	_rc_roll->calc_pwm();
	_rc_pitch->calc_pwm();
	_rc_throttle->calc_pwm();
	_rc_yaw->calc_pwm();

	move_swash( _rc_roll->servo_out, _rc_pitch->servo_out, _rc_throttle->servo_out, _rc_yaw->servo_out );
	
	ext_esc_control();
}

// output_disarmed - sends commands to the motors
void AP_MotorsHeli::output_disarmed()
{
	if(_rc_throttle->control_in > 0){
		// we have pushed up the throttle
		// remove safety
		_auto_armed = true;
	}

	// for helis - armed or disarmed we allow servos to move
	output_armed();
}

// output_disarmed - sends commands to the motors
void AP_MotorsHeli::output_test()
{
	int16_t i;
	// Send minimum values to all motors
	output_min();

	// servo 1
	for( i=0; i<5; i++ ) {
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_1], _servo_1->radio_trim + 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_1], _servo_1->radio_trim - 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_1], _servo_1->radio_trim + 0);
		delay(300);
	}

	// servo 2
	for( i=0; i<5; i++ ) {
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_2], _servo_2->radio_trim + 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_2], _servo_2->radio_trim - 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_2], _servo_2->radio_trim + 0);
		delay(300);
	}

	// servo 3
	for( i=0; i<5; i++ ) {
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_3], _servo_3->radio_trim + 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_3], _servo_3->radio_trim - 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_3], _servo_3->radio_trim + 0);
		delay(300);
	}

	// external gyro
	if( ext_gyro_enabled ) {
		_rc->OutputCh(AP_MOTORS_HELI_EXT_GYRO, ext_gyro_gain);
	}

	// servo 4
	for( i=0; i<5; i++ ) {
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_4], _servo_4->radio_trim + 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_4], _servo_4->radio_trim - 100);
		delay(300);
		_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_4], _servo_4->radio_trim + 0);
		delay(300);
	}

	// Send minimum values to all motors
	output_min();
}

// reset_swash - free up swash for maximum movements. Used for set-up
void AP_MotorsHeli::reset_swash()
{
	// free up servo ranges
	_servo_1->radio_min = 1000;
	_servo_1->radio_max = 2000;
	_servo_2->radio_min = 1000;
	_servo_2->radio_max = 2000;
	_servo_3->radio_min = 1000;
	_servo_3->radio_max = 2000;

	if( swash_type == AP_MOTORS_HELI_SWASH_CCPM ) {			//CCPM Swashplate, perform servo control mixing
		
		// roll factors
		_rollFactor[CH_1] = cos(radians(servo1_pos + 90 - phase_angle));
		_rollFactor[CH_2] = cos(radians(servo2_pos + 90 - phase_angle));
		_rollFactor[CH_3] = cos(radians(servo3_pos + 90 - phase_angle));
				
		// pitch factors
		_pitchFactor[CH_1] = cos(radians(servo1_pos - phase_angle));
		_pitchFactor[CH_2] = cos(radians(servo2_pos - phase_angle));
		_pitchFactor[CH_3] = cos(radians(servo3_pos - phase_angle));
		
		// collective factors
		_collectiveFactor[CH_1] = 1;
		_collectiveFactor[CH_2] = 1;
		_collectiveFactor[CH_3] = 1;
		
	}else{  								//H1 Swashplate, keep servo outputs seperated

		// roll factors
		_rollFactor[CH_1] = 1;
		_rollFactor[CH_2] = 0;
		_rollFactor[CH_3] = 0;
	
		// pitch factors
		_pitchFactor[CH_1] = 0;
		_pitchFactor[CH_2] = 1;
		_pitchFactor[CH_3] = 0;
		
		// collective factors
		_collectiveFactor[CH_1] = 0;
		_collectiveFactor[CH_2] = 0;
		_collectiveFactor[CH_3] = 1;
	}

	// set roll, pitch and throttle scaling
	_roll_scaler = 1.0;
	_pitch_scaler = 1.0;
	_collective_scalar = ((float)(_rc_throttle->radio_max - _rc_throttle->radio_min))/1000.0;

	// we must be in set-up mode so mark swash as uninitialised
	_swash_initialised = false;
}

// init_swash - initialise the swash plate
void AP_MotorsHeli::init_swash()
{

	// swash servo initialisation
	_servo_1->set_range(0,1000);
	_servo_2->set_range(0,1000);
	_servo_3->set_range(0,1000);
	_servo_4->set_angle(4500);

	// ensure _coll values are reasonable
	if( collective_min >= collective_max ) {
	    collective_min = 1000;
		collective_max = 2000;
	}
	collective_mid = constrain(collective_mid, collective_min, collective_max);

	// calculate throttle mid point
	throttle_mid = ((float)(collective_mid-collective_min))/((float)(collective_max-collective_min))*1000.0;

	// determine roll, pitch and throttle scaling
	_roll_scaler = (float)roll_max/4500.0;
	_pitch_scaler = (float)pitch_max/4500.0;
	_collective_scalar = ((float)(collective_max-collective_min))/1000.0;

	if( swash_type == AP_MOTORS_HELI_SWASH_CCPM ) {			//CCPM Swashplate, perform control mixing
		
		// roll factors
		_rollFactor[CH_1] = cos(radians(servo1_pos + 90 - phase_angle));
		_rollFactor[CH_2] = cos(radians(servo2_pos + 90 - phase_angle));
		_rollFactor[CH_3] = cos(radians(servo3_pos + 90 - phase_angle));
				
		// pitch factors
		_pitchFactor[CH_1] = cos(radians(servo1_pos - phase_angle));
		_pitchFactor[CH_2] = cos(radians(servo2_pos - phase_angle));
		_pitchFactor[CH_3] = cos(radians(servo3_pos - phase_angle));
		
		// collective factors
		_collectiveFactor[CH_1] = 1;
		_collectiveFactor[CH_2] = 1;
		_collectiveFactor[CH_3] = 1;
		
	}else{  	//H1 Swashplate, keep servo outputs seperated

		// roll factors
		_rollFactor[CH_1] = 1;
		_rollFactor[CH_2] = 0;
		_rollFactor[CH_3] = 0;
	
		// pitch factors
		_pitchFactor[CH_1] = 0;
		_pitchFactor[CH_2] = 1;
		_pitchFactor[CH_3] = 0;
		
		// collective factors
		_collectiveFactor[CH_1] = 0;
		_collectiveFactor[CH_2] = 0;
		_collectiveFactor[CH_3] = 1;
	}

	// servo min/max values
	_servo_1->radio_min = 1000;
	_servo_1->radio_max = 2000;
	_servo_2->radio_min = 1000;
	_servo_2->radio_max = 2000;
	_servo_3->radio_min = 1000;
	_servo_3->radio_max = 2000;

	// mark swash as initialised
	_swash_initialised = true;
}

//
// heli_move_swash - moves swash plate to attitude of parameters passed in
//                 - expected ranges:
//                       roll : -4500 ~ 4500
//                       pitch: -4500 ~ 4500
//                       collective: 0 ~ 1000
//                       yaw:   -4500 ~ 4500
//
void AP_MotorsHeli::move_swash(int16_t roll_out, int16_t pitch_out, int16_t coll_out, int16_t yaw_out)
{
	int16_t yaw_offset = 0;
	int16_t coll_out_scaled;

	if( servo_manual == 1 ) {  // are we in manual servo mode? (i.e. swash set-up mode)?
		// check if we need to free up the swash
		if( _swash_initialised ) {
			reset_swash();
		}
		coll_out_scaled = coll_out * _collective_scalar + _rc_throttle->radio_min - 1000;
	}else{  // regular flight mode

		// check if we need to reinitialise the swash
		if( !_swash_initialised ) {
			init_swash();
		}
		
		// rescale roll_out and pitch-out into the min and max ranges to provide linear motion 
		// across the input range instead of stopping when the input hits the constrain value
		// these calculations are based on an assumption of the user specified roll_max and pitch_max 
		// coming into this equation at 4500 or less, and based on the original assumption of the  
		// total _servo_x.servo_out range being -4500 to 4500.
		roll_out = roll_out * _roll_scaler;
		roll_out = constrain(roll_out, (int16_t)-roll_max, (int16_t)roll_max);

		pitch_out = pitch_out * _pitch_scaler;
		pitch_out = constrain(pitch_out, (int16_t)-pitch_max, (int16_t)pitch_max);

	    // scale collective pitch
		coll_out = constrain(coll_out, 0, 1000);
		coll_out_scaled = coll_out * _collective_scalar + collective_min - 1000;

		// rudder feed forward based on collective
		if( !ext_gyro_enabled ) {
			yaw_offset = collective_yaw_effect * abs(coll_out_scaled - throttle_mid);
		}
	}

	// swashplate servos
	_servo_1->servo_out = (_rollFactor[CH_1] * roll_out + _pitchFactor[CH_1] * pitch_out)/10 + _collectiveFactor[CH_1] * coll_out_scaled + (_servo_1->radio_trim-1500);
	_servo_2->servo_out = (_rollFactor[CH_2] * roll_out + _pitchFactor[CH_2] * pitch_out)/10 + _collectiveFactor[CH_2] * coll_out_scaled + (_servo_2->radio_trim-1500);
	if( swash_type == AP_MOTORS_HELI_SWASH_H1 ) {
		_servo_1->servo_out += 500;
		_servo_2->servo_out += 500;
	}
	_servo_3->servo_out = (_rollFactor[CH_3] * roll_out + _pitchFactor[CH_3] * pitch_out)/10 + _collectiveFactor[CH_3] * coll_out_scaled + (_servo_3->radio_trim-1500);
	_servo_4->servo_out = yaw_out + yaw_offset;

	// use servo_out to calculate pwm_out and radio_out
	_servo_1->calc_pwm();
	_servo_2->calc_pwm();
	_servo_3->calc_pwm();
	_servo_4->calc_pwm();

	// actually move the servos
	_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_1], _servo_1->radio_out);
	_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_2], _servo_2->radio_out);
	_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_3], _servo_3->radio_out);
	_rc->OutputCh(_motor_to_channel_map[AP_MOTORS_MOT_4], _servo_4->radio_out);

	// to be compatible with other frame types
	motor_out[AP_MOTORS_MOT_1] = _servo_1->radio_out;
	motor_out[AP_MOTORS_MOT_2] = _servo_2->radio_out;
	motor_out[AP_MOTORS_MOT_3] = _servo_3->radio_out;
	motor_out[AP_MOTORS_MOT_4] = _servo_4->radio_out;

	// output gyro value
	if( ext_gyro_enabled ) {
		_rc->OutputCh(AP_MOTORS_HELI_EXT_GYRO, ext_gyro_gain);
	}

	// InstantPWM
	if( _speed_hz == AP_MOTORS_SPEED_INSTANT_PWM ) {
		_rc->Force_Out0_Out1();
		_rc->Force_Out2_Out3();
	}
}

void AP_MotorsHeli::ext_esc_control()

{
	switch ( AP_MOTORS_EXT_ESC_ACTIVE ) {

		case AP_MOTORS_ESC_MODE_PASSTHROUGH: 																	
			if( armed() && _rc_8->control_in > 10 ){
				if (ext_esc_ramp < AP_MOTORS_EXT_ESC_RAMP_UP){
					ext_esc_ramp++;
					ext_esc_output = map(ext_esc_ramp, 0, AP_MOTORS_EXT_ESC_RAMP_UP, 1000, _rc_8->control_in);
				} else {
					ext_esc_output = _rc_8->control_in;
				}	
			} else if( !armed() ) {
				_rc->OutputCh(AP_MOTORS_HELI_EXT_ESC, _rc_8->radio_min);
				ext_esc_ramp = 0;	//Return ESC Ramp to 0
			}
		break;
		
		case AP_MOTORS_ESC_MODE_EXT_GOV:																		
				
			if( armed() && _rc_throttle->control_in > 10){
				if (ext_esc_ramp < AP_MOTORS_EXT_ESC_RAMP_UP){
					ext_esc_ramp++;
					ext_esc_output = map(ext_esc_ramp, 0, AP_MOTORS_EXT_ESC_RAMP_UP, 1000, ext_gov_setpoint);
				} else {
					ext_esc_output = ext_gov_setpoint;
				}
			} else {
				ext_esc_ramp--;	//Return ESC Ramp to 0
				if (ext_esc_ramp < 0){
					ext_esc_ramp = 0;
				}
				ext_esc_output = 1000; //Just to be sure ESC output is 0
			}
			_rc->OutputCh(AP_MOTORS_HELI_EXT_ESC, ext_esc_output);
		break;
		
		//	case 3:																		// Open Loop ESC Control
		//
		//	coll_scaled = _motors->coll_out_scaled + 1000;
		//	if(coll_scaled <= _motors->collective_mid){
		//		esc_ol_output = map(coll_scaled, _motors->collective_min, _motors->collective_mid, esc_out_low, esc_out_mid);		// Bottom half of V-curve
		//	} else if (coll_scaled > _motors->collective_mid){
		//		esc_ol_output = map(coll_scaled, _motors->collective_mid, _motors->collective_max, esc_out_mid, esc_out_high);		// Top half of V-curve
		//	} else { esc_ol_output = 1000; }																									// Just in case.
		//
		//	if(_motors->armed() && _rc_throttle->control_in > 10){
		//			if (ext_esc_ramp < ext_esc_ramp_up){
		//				ext_esc_ramp++;
		//				ext_esc_output = map(ext_esc_ramp, 0, ext_esc_ramp_up, 1000, esc_ol_output);
		//			} else {
		//				ext_esc_output = esc_ol_output;
		//			}
		//		} else {
		//			ext_esc_ramp = 0;	//Return ESC Ramp to 0
		//			ext_esc_output = 1000; //Just to be sure ESC output is 0
		//}
		//		_rc->OutputCh(AP_MOTORS_HELI_EXT_ESC, ext_esc_output);
		//	break;
		
			
		default:
		break;
	}
};