/*
  spindle_control.c - spindle control methods
  Part of Grbl

  Copyright (c) 2012-2017 Sungeun K. Jeon for Gnea Research LLC
  Copyright (c) 2009-2011 Simen Svale Skogsrud

  Grbl 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.

  Grbl 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 Grbl.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "grbl.h"

#ifdef VARIABLE_SPINDLE
static float pwm_gradient; // Precalulated value to speed up rpm to PWM conversions.
#endif

void spindle_init() {
#ifdef VARIABLE_SPINDLE
    // Configure variable spindle PWM and enable pin, if requried. On the Uno, PWM and enable are
    // combined unless configured otherwise.
    SPINDLE_PWM_DDR |= (1 << SPINDLE_PWM_BIT);        // Configure as PWM output pin.
    SPINDLE_TCCRA_REGISTER = SPINDLE_TCCRA_INIT_MASK; // Configure PWM output compare timer
    SPINDLE_TCCRB_REGISTER = SPINDLE_TCCRB_INIT_MASK;
#ifdef USE_SPINDLE_DIR_AS_ENABLE_PIN
    SPINDLE_ENABLE_DDR |= (1 << SPINDLE_ENABLE_BIT); // Configure as output pin.
#else
#ifndef ENABLE_DUAL_AXIS
    SPINDLE_DIRECTION_DDR |= (1 << SPINDLE_DIRECTION_BIT); // Configure as output pin.
#endif
#endif
    pwm_gradient = SPINDLE_PWM_RANGE / (settings.rpm_max - settings.rpm_min);
#else
    SPINDLE_ENABLE_DDR |= (1 << SPINDLE_ENABLE_BIT); // Configure as output pin.
#ifndef ENABLE_DUAL_AXIS
    SPINDLE_DIRECTION_DDR |= (1 << SPINDLE_DIRECTION_BIT); // Configure as output pin.
#endif
#endif

    spindle_stop();
}

uint8_t spindle_get_state() {
#ifdef VARIABLE_SPINDLE
#ifdef USE_SPINDLE_DIR_AS_ENABLE_PIN
// No spindle direction output pin.
#ifdef INVERT_SPINDLE_ENABLE_PIN
    if (bit_isfalse(SPINDLE_ENABLE_PORT, (1 << SPINDLE_ENABLE_BIT))) {
        return (SPINDLE_STATE_CW);
    }
#else
    if (bit_istrue(SPINDLE_ENABLE_PORT, (1 << SPINDLE_ENABLE_BIT))) {
        return (SPINDLE_STATE_CW);
    }
#endif
#else
    if (SPINDLE_TCCRA_REGISTER & (1 << SPINDLE_COMB_BIT)) { // Check if PWM is enabled.
#ifdef ENABLE_DUAL_AXIS
        return (SPINDLE_STATE_CW);
#else
        if (SPINDLE_DIRECTION_PORT & (1 << SPINDLE_DIRECTION_BIT)) {
            return (SPINDLE_STATE_CCW);
        } else {
            return (SPINDLE_STATE_CW);
        }
#endif
    }
#endif
#else
#ifdef INVERT_SPINDLE_ENABLE_PIN
    if (bit_isfalse(SPINDLE_ENABLE_PORT, (1 << SPINDLE_ENABLE_BIT))) {
#else
    if (bit_istrue(SPINDLE_ENABLE_PORT, (1 << SPINDLE_ENABLE_BIT))) {
#endif
#ifdef ENABLE_DUAL_AXIS
        return (SPINDLE_STATE_CW);
#else
        if (SPINDLE_DIRECTION_PORT & (1 << SPINDLE_DIRECTION_BIT)) {
            return (SPINDLE_STATE_CCW);
        } else {
            return (SPINDLE_STATE_CW);
        }
#endif
    }
#endif
    return (SPINDLE_STATE_DISABLE);
}

// Disables the spindle and sets PWM output to zero when PWM variable spindle speed is enabled.
// Called by various main program and ISR routines. Keep routine small, fast, and efficient.
// Called by spindle_init(), spindle_set_speed(), spindle_set_state(), and mc_reset().
void spindle_stop() {
#ifdef VARIABLE_SPINDLE
    SPINDLE_TCCRA_REGISTER &= ~(1 << SPINDLE_COMB_BIT); // Disable PWM. Output voltage is zero.
#ifdef USE_SPINDLE_DIR_AS_ENABLE_PIN
#ifdef INVERT_SPINDLE_ENABLE_PIN
    SPINDLE_ENABLE_PORT |= (1 << SPINDLE_ENABLE_BIT); // Set pin to high
#else
    SPINDLE_ENABLE_PORT &= ~(1 << SPINDLE_ENABLE_BIT); // Set pin to low
#endif
#endif
#else
#ifdef INVERT_SPINDLE_ENABLE_PIN
    SPINDLE_ENABLE_PORT |= (1 << SPINDLE_ENABLE_BIT); // Set pin to high
#else
    SPINDLE_ENABLE_PORT &= ~(1 << SPINDLE_ENABLE_BIT); // Set pin to low
#endif
#endif
}

#ifdef VARIABLE_SPINDLE
// Sets spindle speed PWM output and enable pin, if configured. Called by spindle_set_state()
// and stepper ISR. Keep routine small and efficient.
void spindle_set_speed(uint8_t pwm_value) {
    SPINDLE_OCR_REGISTER = pwm_value; // Set PWM output level.
#ifdef SPINDLE_ENABLE_OFF_WITH_ZERO_SPEED
    if (pwm_value == SPINDLE_PWM_OFF_VALUE) {
        spindle_stop();
    } else {
        SPINDLE_TCCRA_REGISTER |= (1 << SPINDLE_COMB_BIT); // Ensure PWM output is enabled.
#ifdef INVERT_SPINDLE_ENABLE_PIN
        SPINDLE_ENABLE_PORT &= ~(1 << SPINDLE_ENABLE_BIT);
#else
        SPINDLE_ENABLE_PORT |= (1 << SPINDLE_ENABLE_BIT);
#endif
    }
#else
    if (pwm_value == SPINDLE_PWM_OFF_VALUE) {
        SPINDLE_TCCRA_REGISTER &= ~(1 << SPINDLE_COMB_BIT); // Disable PWM. Output voltage is zero.
    } else {
        SPINDLE_TCCRA_REGISTER |= (1 << SPINDLE_COMB_BIT); // Ensure PWM output is enabled.
    }
#endif
}

#ifdef ENABLE_PIECEWISE_LINEAR_SPINDLE

// Called by spindle_set_state() and step segment generator. Keep routine small and efficient.
uint8_t spindle_compute_pwm_value(float rpm) // 328p PWM register is 8-bit.
{
    uint8_t pwm_value;
    rpm *= (0.010 * sys.spindle_speed_ovr); // Scale by spindle speed override value.
    // Calculate PWM register value based on rpm max/min settings and programmed rpm.
    if ((settings.rpm_min >= settings.rpm_max) || (rpm >= RPM_MAX)) {
        rpm = RPM_MAX;
        pwm_value = SPINDLE_PWM_MAX_VALUE;
    } else if (rpm <= RPM_MIN) {
        if (rpm == 0.0) { // S0 disables spindle
            pwm_value = SPINDLE_PWM_OFF_VALUE;
        } else {
            rpm = RPM_MIN;
            pwm_value = SPINDLE_PWM_MIN_VALUE;
        }
    } else {
// Compute intermediate PWM value with linear spindle speed model via piecewise linear fit model.
#if (N_PIECES > 3)
        if (rpm > RPM_POINT34) {
            pwm_value = floor(RPM_LINE_A4 * rpm - RPM_LINE_B4);
        } else
#endif
#if (N_PIECES > 2)
            if (rpm > RPM_POINT23) {
            pwm_value = floor(RPM_LINE_A3 * rpm - RPM_LINE_B3);
        } else
#endif
#if (N_PIECES > 1)
            if (rpm > RPM_POINT12) {
            pwm_value = floor(RPM_LINE_A2 * rpm - RPM_LINE_B2);
        } else
#endif
        {
            pwm_value = floor(RPM_LINE_A1 * rpm - RPM_LINE_B1);
        }
    }
    sys.spindle_speed = rpm;
    return (pwm_value);
}

#else

// Called by spindle_set_state() and step segment generator. Keep routine small and efficient.
uint8_t spindle_compute_pwm_value(float rpm) // 328p PWM register is 8-bit.
{
    uint8_t pwm_value;
    rpm *= (0.010 * sys.spindle_speed_ovr); // Scale by spindle speed override value.
    // Calculate PWM register value based on rpm max/min settings and programmed rpm.
    if ((settings.rpm_min >= settings.rpm_max) || (rpm >= settings.rpm_max)) {
        // No PWM range possible. Set simple on/off spindle control pin state.
        sys.spindle_speed = settings.rpm_max;
        pwm_value = SPINDLE_PWM_MAX_VALUE;
    } else if (rpm <= settings.rpm_min) {
        if (rpm == 0.0) { // S0 disables spindle
            sys.spindle_speed = 0.0;
            pwm_value = SPINDLE_PWM_OFF_VALUE;
        } else { // Set minimum PWM output
            sys.spindle_speed = settings.rpm_min;
            pwm_value = SPINDLE_PWM_MIN_VALUE;
        }
    } else {
        // Compute intermediate PWM value with linear spindle speed model.
        // NOTE: A nonlinear model could be installed here, if required, but keep it VERY light-weight.
        sys.spindle_speed = rpm;
        pwm_value = floor((rpm - settings.rpm_min) * pwm_gradient) + SPINDLE_PWM_MIN_VALUE;
    }
    return (pwm_value);
}

#endif
#endif

// Immediately sets spindle running state with direction and spindle rpm via PWM, if enabled.
// Called by g-code parser spindle_sync(), parking retract and restore, g-code program end,
// sleep, and spindle stop override.
#ifdef VARIABLE_SPINDLE
void spindle_set_state(uint8_t state, float rpm)
#else
void _spindle_set_state(uint8_t state)
#endif
{
    if (sys.abort) {
        return;
    } // Block during abort.

    if (state == SPINDLE_DISABLE) { // Halt or set spindle direction and rpm.

#ifdef VARIABLE_SPINDLE
        sys.spindle_speed = 0.0;
#endif
        spindle_stop();

    } else {

#if !defined(USE_SPINDLE_DIR_AS_ENABLE_PIN) && !defined(ENABLE_DUAL_AXIS)
        if (state == SPINDLE_ENABLE_CW) {
            SPINDLE_DIRECTION_PORT &= ~(1 << SPINDLE_DIRECTION_BIT);
        } else {
            SPINDLE_DIRECTION_PORT |= (1 << SPINDLE_DIRECTION_BIT);
        }
#endif

#ifdef VARIABLE_SPINDLE
        // NOTE: Assumes all calls to this function is when Grbl is not moving or must remain off.
        if (settings.flags & BITFLAG_LASER_MODE) {
            if (state == SPINDLE_ENABLE_CCW) {
                rpm = 0.0;
            } // TODO: May need to be rpm_min*(100/MAX_SPINDLE_SPEED_OVERRIDE);
        }
        spindle_set_speed(spindle_compute_pwm_value(rpm));
#endif
#if (defined(USE_SPINDLE_DIR_AS_ENABLE_PIN) && !defined(SPINDLE_ENABLE_OFF_WITH_ZERO_SPEED)) ||                        \
    !defined(VARIABLE_SPINDLE)
// NOTE: Without variable spindle, the enable bit should just turn on or off, regardless
// if the spindle speed value is zero, as its ignored anyhow.
#ifdef INVERT_SPINDLE_ENABLE_PIN
        SPINDLE_ENABLE_PORT &= ~(1 << SPINDLE_ENABLE_BIT);
#else
        SPINDLE_ENABLE_PORT |= (1 << SPINDLE_ENABLE_BIT);
#endif
#endif
    }

    sys.report_ovr_counter = 0; // Set to report change immediately
}

// G-code parser entry-point for setting spindle state. Forces a planner buffer sync and bails
// if an abort or check-mode is active.
#ifdef VARIABLE_SPINDLE
void spindle_sync(uint8_t state, float rpm) {
    if (sys.state == STATE_CHECK_MODE) {
        return;
    }
    protocol_buffer_synchronize(); // Empty planner buffer to ensure spindle is set when programmed.
    spindle_set_state(state, rpm);
}
#else
void _spindle_sync(uint8_t state) {
    if (sys.state == STATE_CHECK_MODE) {
        return;
    }
    protocol_buffer_synchronize(); // Empty planner buffer to ensure spindle is set when programmed.
    _spindle_set_state(state);
}
#endif