#include "PinChangeInterrupt.h"
#include "AiEsp32RotaryEncoder.h"
#include "Arduino.h"
#include <Wire.h>              // include the Wire library for I2C communication
#include <RTClib.h>            // include the RTClib library for accessing the RTC module
#include <Adafruit_SSD1306.h>  // include the Adafruit_SSD1306 library for the OLED display
// #include <Adafruit_GFX.h>    // Core graphics library
// #include <Adafruit_TFTLCD.h> // Hardware-specific library
// #include <Fonts/FreeSans9pt7b.h>

RTC_DS3231 rtc;               // create an RTC object
Adafruit_SSD1306 display(128, 64, &Wire, -1);  // create an OLED display object
#define CLK 2
#define DT 3
#define SW 4
float counter = 65;
int currentState;
int initState;
unsigned long debounceDelay = 0;
bool isPressed = 0;
void setup() {
  pinMode(CLK, INPUT);
  pinMode(DT, INPUT);
  pinMode(SW, INPUT_PULLUP);

  // Setup Serial Monitor
  Serial.begin(9600);

  // Read the initial state of CLK
  initState = digitalRead(CLK);

  // Call encoder_value() when any high/low changed seen
  // on interrupt 0 (pin 2), or interrupt 1 (pin 3)
  attachInterrupt(0, encoder_value, CHANGE);
  attachInterrupt(1, encoder_value, CHANGE);
  attachPCINT(digitalPinToPCINT(SW), button_press, CHANGE);
    Wire.begin();              // start the I2C communication
  rtc.begin();               // start the RTC module
  display.begin(SSD1306_SWITCHCAPVCC, 0x3C);  // start the OLED display
  display.clearDisplay();    // clear the display buffer
  display.setTextSize(2);    // set the text size to 2
  display.setTextColor(WHITE);  // set the text color to white
// display.setFont(&FreeSans9pt7b);
}


void loop()
{
  DateTime now = rtc.now();   // get the current date and time from the RTC module
  display.clearDisplay();     // clear the display buffer
  display.setCursor(0, 0);    // set the cursor position to (0,0)
  display.println("Date: ");    // print the text "Date: "
  display.print(now.day(), DEC);   // print the day of the month
  display.print("/");         // print a slash separator
  display.print(now.month(), DEC);  // print the month
  display.print("/");         // print a slash separator
  display.println(now.year(), DEC);  // print the year
  display.setCursor(18, 40);
  display.print(counter);
  display.print(" kg");
  display.display();
  Serial.print(isPressed);

  isPressed == 1? display.invertDisplay(true):display.invertDisplay(false);
  delay(10);                // wait for one second before updating the display again
}


void button_press()
{
  int buttonVal = digitalRead(SW);
  //If we detect LOW signal, button is pressed
  if (isPressed == 0 && buttonVal == LOW) {
    if (millis() - debounceDelay > 200) {
      Serial.println("Button pressed!");
      isPressed = true;
    }
    debounceDelay = millis();
  } else if (isPressed == 1 && buttonVal == LOW) {
    if (millis() - debounceDelay > 200) {
      Serial.println("Button pressed!");
      isPressed = false;
    }
  }  
}


void encoder_value() {
  // Read the current state of CLK
  currentState = digitalRead(CLK);

  // If last and current state of CLK are different, then we can be sure that the pulse occurred
  if (currentState != initState  && currentState == 1) {
    // Encoder is rotating counterclockwise so we decrement the counter
    if (digitalRead(DT) != currentState) {
      counter += 0.05;
    } else {
      // Encoder is rotating clockwise so we increment the counter
      counter -= 0.05;
    }
    // print the value in the serial monitor window
    Serial.print("Counter: ");
    Serial.println(counter);
  }
  // Remember last CLK state for next cycle
  initState = currentState;
}