#include <Wire.h>
#include <U8g2lib.h> // U8g2 library for drawing on OLED display

// Define the pins for the rotary encoder
#define ENCODER_CLK 33    // Connect to the CLK (A) pin of the rotary encoder
#define ENCODER_DT 25     // Connect to the DT (B) pin of the rotary encoder
#define ENCODER_SW 26     // Connect to the SW (Button) pin of the rotary encoder

// Initialize the U8g2 display object (assuming I2C communication)
U8G2_SH1106_128X64_NONAME_F_HW_I2C u8g2(U8G2_R2, U8X8_PIN_NONE, U8X8_PIN_NONE); // SH1107 or SSD1306, adjust for your screen

int lastState = LOW;
int position = 0;  // Current position of the rotary encoder
int buttonState = LOW;
int lastButtonState = LOW;

void setup() {
  Serial.begin(115200);  // Start serial communication for debugging

  // Set the pins for the encoder as input
  pinMode(ENCODER_CLK, INPUT);
  pinMode(ENCODER_DT, INPUT);
  pinMode(ENCODER_SW, INPUT_PULLUP);  // If you have a button

  lastState = digitalRead(ENCODER_CLK); // Read the initial state of CLK pin

  // Initialize the OLED display
  u8g2.begin();  // Begin the u8g2 library
  u8g2.setContrast(255); // Set display contrast/brightness
}

void loop() {
  int currentState = digitalRead(ENCODER_CLK);
  int currentButtonState = digitalRead(ENCODER_SW);

  // Check if the encoder's CLK pin state has changed
  if (currentState != lastState) {
    // Determine the direction based on the state of the DT pin
    if (digitalRead(ENCODER_DT) == LOW) {
      position++;  // Increment the position (clockwise)
      Serial.println("Rotated clockwise ⏩");
    } else {
      position--;  // Decrement the position (counter-clockwise)
      Serial.println("Rotated counterclockwise ⏪");
    }

    // Print the current position (steps) to the Serial Monitor
    Serial.print("Current Position: ");
    Serial.println(position);

    // Update the OLED display with the current position
    u8g2.clearBuffer();  // Clear the display buffer
    u8g2.setFont(u8g2_font_ncenB08_tr);  // Choose a font
    u8g2.setCursor(0, 0);  // Set cursor position
    u8g2.print("Position: ");
    u8g2.print(position);  // Display the current position value
    u8g2.sendBuffer();  // Draw the buffer to the display

    lastState = currentState; // Update the last state to the current state
  }

  // Button press logic (if using a button)
  if (currentButtonState == LOW && lastButtonState == HIGH) {
    Serial.println("Button Pressed!");
    // You can add additional actions for button press here
  }

  lastButtonState = currentButtonState;  // Update the button state

  delay(10);  // Small delay to debounce the input
}


// NOTES:
// SH1107 OLED SCREEN
// IIC connection of the OLED display and Arduino UNO
// +5V > +5V
// GND > GND
// SCL (serial clock) > A5 or SCL
// SDA (serial data) > A4 or SDA