Sesame-Device/include/servo.h

#pragma once

#include <stdint.h>
#include <ESP32Servo.h> // To control the servo

struct ServoConfiguration {
    /**
     * @brief The timer to use for the servo control
     * number 0-3 indicating which timer to allocate in this library
     */
    int pwmTimer;

    /**
     * @brief The servo frequency (depending on the model used)
     */
    int pwmFrequency;

    /**
     * @brief The pin where the servo PWM line is connected
     */
    int pin;

    /**
     * @brief The duration (in ms) for which the button should remain pressed
     */
    uint32_t openDuration;

    /**
     * @brief The servo value (in µs) that specifies the 'pressed' state
     */
    int pressedValue;

    /**
     * @brief The servo value (in µs) that specifies the 'released' state
     */
    int releasedValue;

};

/**
 * @brief A controller for the button control servo
 * 
 * The controller simply configures the servo for operation,
 * and then sets the desired servo value for the 'pressed' and 'released' states.
 * The controller requires periodic updating through the `loop()` function
 * in order to release the button after the specified time.
 * 
 */
class ServoController {

public:

    /**
     * @brief Construct a new servo controller
     * 
     * @param The configuration for the servo
     */
    ServoController(ServoConfiguration configuration);

    /**
     * @brief Update the servo state periodically
     * 
     * This function will be periodically called to update the servo state,
     * specifically to release the button after the opening time has elapsed.
     * 
     * There is no required interval to call this function, but the accuracy of
     * the opening interval is dependent on the calling frequency.
     */
    void loop(uint32_t millis);

    /**
     * Push the door opener button down by moving the servo arm.
     */
    void pressButton();

private:

    // Indicator that the door button is pushed
    bool buttonIsPressed = false;

    // Indicate that the button should be pressed
    bool shouldPressButton = false;

    uint32_t openDuration = 0;

    int pressedValue = 0;

    int releasedValue = 0;

    // The time (in ms since start) when the door opening should end
    uint32_t openingEndTime = 0;

    // Servo controller
    Servo servo;

    // PWM Module needed for the servo
    ESP32PWM pwm;

    // The task on core 1 that resets the servo
    TaskHandle_t servoResetTask;

    /**
     * Release the door opener button by moving the servo arm.
     */
    void releaseButton();

};