/*
  State change detection (edge detection)
  https://wokwi.com/projects/391475222059330561

  Often, you don't need to know the state of a digital input all the time, but
  you just need to know when the input changes from one state to another.
  For example, you want to know when a button goes from OFF to ON. This is called
  state change detection, or edge detection.

  This example shows how to detect when a button or button changes from off to on
  and on to off.

  The circuit:
  - pushbutton attached to pin 2 from +5V
  - 10 kilohm resistor attached to pin 2 from ground
  - LED attached from pin 13 to ground through 220 ohm resistor (or use the
    built-in LED on most Arduino boards)

  created  27 Sep 2005
  modified 30 Aug 2011
  by Tom Igoe

  This example code is in the public domain.

  https://docs.arduino.cc/built-in-examples/digital/StateChangeDetection/
*/

// Includes

#include "proto_activities.h"

// Constants

const int buttonPin = 2;  // the pin that the pushbutton is attached to
const int ledPin = 13;    // the pin that the LED is attached to

// Activities

// Recognizes the push of the button and reports it in the output parameter
pa_activity (ButtonPushRecognizer, pa_ctx_tm(), bool& pushed) {
  // initialize the button pin as a input:
  pinMode(buttonPin, INPUT);

  pa_every ((digitalRead(buttonPin) == HIGH)) {
    pushed = true;
    pa_pause;
    pushed = false;
    pa_delay_ms (50);
    pa_await (digitalRead(buttonPin) == LOW);
    pa_delay_ms (50);
  } pa_every_end
} pa_end

// Increments a counter everytime trigger is true
pa_activity (Counter, pa_ctx(), bool trigger, int& counter) {
  pa_every (trigger) {
    ++counter;
  } pa_every_end
} pa_end

// Prints the number of button pushes everytime it changes
pa_activity (ButtonPushLogger, pa_ctx(), int trigger, int counter) {
  pa_every (trigger) {
    Serial.print("number of button pushes: ");
    Serial.println(counter);
  } pa_every_end
} pa_end

// Drives the led according to the parameter
pa_activity (LedDriver, pa_ctx(), bool on) {
  // initialize the LED as an output:
  pinMode(ledPin, OUTPUT);

  pa_repeat {
    if (on) {
      digitalWrite(ledPin, HIGH);
      pa_await (!on);
    }
    digitalWrite(ledPin, LOW);
    pa_await (on);
  }
} pa_end

// Sets up and connects the components
pa_activity (Main, pa_ctx(pa_co_res(4); pa_use(ButtonPushRecognizer); pa_use(Counter); pa_use(ButtonPushLogger); pa_use(LedDriver); bool pushed; int counter)) {
  pa_co(4) {
    pa_with (ButtonPushRecognizer, pa_self.pushed);
    pa_with (Counter, pa_self.pushed, pa_self.counter);
    pa_with (ButtonPushLogger, pa_self.pushed, pa_self.counter);
    pa_with (LedDriver, pa_self.counter % 4 == 0);
  } pa_co_end
} pa_end

pa_use(Main);

// Setup and Loop

void setup() {
  // initialize serial communication:
  Serial.begin(9600);
}

void loop() {
  pa_tick(Main);
}