/**
 * @file digital_output.h
 * @author Adam Wonak (https://github.com/awonak)
 * @brief Class for interacting with trigger / gate outputs.
 * @version 0.1
 * @date 2025-04-17
 * 
 * @copyright MIT - (c) 2025 - Adam Wonak - adam.wonak@gmail.com
 *
 */
#ifndef DIGITAL_OUTPUT_H
#define DIGITAL_OUTPUT_H

#include <Arduino.h>

const byte DEFAULT_TRIGGER_DURATION_MS = 5;

class DigitalOutput {
   public:
    /**
     * Initializes an CV Output paired object.
     *
     * @param cv_pin gpio pin for the cv output
     */
    void Init(uint8_t cv_pin) {
        pinMode(cv_pin, OUTPUT);  // Gate/Trigger Output
        cv_pin_ = cv_pin;
        trigger_duration_ = DEFAULT_TRIGGER_DURATION_MS;
    }

    /**
     * Set the trigger duration in miliseconds.
     *
     * @param duration_ms trigger duration in miliseconds
     */
    void SetTriggerDuration(uint8_t duration_ms) {
        trigger_duration_ = duration_ms;
    }

    /**
     * Turn the CV and LED on or off according to the input state.
     *
     * @param state Arduino digital HIGH or LOW values.
     */
    inline void Update(uint8_t state) {
        if (state == HIGH) High();  // Rising
        if (state == LOW) Low();    // Falling
    }

    // Sets the cv output HIGH to about 5v.
    inline void High() { update(HIGH); }

    // Sets the cv output LOW to 0v.
    inline void Low() { update(LOW); }

    /**
     * Begin a Trigger period for this output.
     */
    inline void Trigger() {
        update(HIGH);
        last_triggered_ = millis();
    }

    /**
     * Return a bool representing the on/off state of the output.
     */
    inline void Process() {
        // If trigger is HIGH and the trigger duration time has elapsed, set the output low.
        if (on_ && (millis() - last_triggered_) >= trigger_duration_) {
            update(LOW);
        }
    }

    /**
     * Return a bool representing the on/off state of the output.
     *
     * @return true if current cv state is high, false if current cv state is low
     */
    inline bool On() { return on_; }

   private:
    unsigned long last_triggered_;
    uint8_t trigger_duration_;
    uint8_t cv_pin_;
    uint8_t led_pin_;
    bool on_;

    void update(uint8_t state) {
        digitalWrite(cv_pin_, state);
        on_ = state == HIGH;
    }
};

#endif