// Including necessary libraries for OLED display and fonts.
#include <Wire.h>
#include <U8g2lib.h>
#include <SPI.h>

// Define the screen width and height
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0, /* clock=*/ SCL, /* data=*/ SDA, /* reset=*/ U8X8_PIN_NONE);

// Define the pin numbers for the LED, potentiometer, battery, and button
int ledPin1 = 5;
int potPin = A1;
int ledPin2 = 6;
int batPin = A2;
int buttonPin = 2; // Changed to pin 2 to support interrupts

// Variables to store the state and time of the button press
volatile unsigned long buttonPressTime = 0;
volatile bool isButtonPressed = false;

// Variables to store the values from the potentiometer and battery
int potIn;
int batIn;

// Variables to hold the PWM values for the LEDs
int percentage1;
int percentage2;
int brightness1;
int brightness2;
// Variable to hold the state of the LED
bool led1State = false;
bool led2State = true;
// Variables to control the LED blinking
unsigned long lastLedChange = 0; // Last time the LED state was changed
unsigned long ledOnTime = 150; // LED on time in milliseconds
unsigned long ledOffTime = 2000; // LED off time in milliseconds

//-------FUNCTION TO HANDLE THE INPUT FOR THE INTERUPT---------//

void handleButtonPress() {

   if (!isButtonPressed) {  // Check if the button was just pressed 
    isButtonPressed = true;
    buttonPressTime = millis();
  }
}

//------------ FUNCTION TO HANDLE PEDAL OUTPUT--------------//

void pedaloutPut(){
// Read the value from the potentiometer
  potIn = analogRead(potPin);

  // Map the potentiometer value to the LED brightness range
  brightness1 = map(potIn, 0, 1023, 0, 255);

  // Map the brightness value to a percentage range
  percentage1 = map(brightness1, 0, 255, 0, 100);

}

//------------ FUNCTION TO SIMULATE BATTERY STATE--------------//

void batteryState(){
// Read the value from the battery
  batIn = analogRead(batPin);

  // Map the battery value to the LED brightness range
  brightness2 = map(batIn, 0, 1023, 0, 255);

  // Map the brightness value to a percentage range
  percentage2 = map(brightness2, 0, 255, 0, 100);

}

// ---------------FUNCTION TO HANDLE TIMER AND CLEAR OLED--------------//
// -------------AND SWITCH POWER ON AND OFF TO TRANSMIT MCU------------//

void timerOledclear(){
// Check if the button is pressed
  if (digitalRead(buttonPin) == LOW) {
    // Check if the button was just pressed
    if (!isButtonPressed) {
      isButtonPressed = true;
      buttonPressTime = millis();
    }
    // Check if the button has been pressed for 5 seconds
    else if (millis() - buttonPressTime >= 5000) {
      // Blink the LED without delay
      if (led1State && millis() - lastLedChange >= ledOnTime) {
        led1State = false;
        lastLedChange = millis();
        digitalWrite(ledPin1, LOW);
      } else if (!led1State && millis() - lastLedChange >= ledOffTime) {
        led1State = true;
        lastLedChange = millis();
        digitalWrite(ledPin1, HIGH);
      }
      
      u8g2.clearBuffer();
      u8g2.sendBuffer();
      // Turn off the LED when the button is pressed
      digitalWrite(ledPin2, LOW);
      // Set the button state to pressed
      isButtonPressed = true;

      // Exit the loop
      return;
    }
  } else {
    
    isButtonPressed = false;// Set the button state to not pressed


  }
   
    digitalWrite(ledPin2, HIGH);// Turn on the LED when the button is released
  
  u8g2.clearBuffer();// Update the buffer with the percentage values
  u8g2.setFont(u8g2_font_ncenB10_tr);
  u8g2.setCursor(0, 20);
  u8g2.print("Output:");
  u8g2.setFont(u8g2_font_ncenB14_tr);
  u8g2.setCursor(68, 22);
  u8g2.print(percentage1);
  u8g2.print("%");

  u8g2.setFont(u8g2_font_ncenB10_tr);
  u8g2.setCursor(0, 54);
  u8g2.print("Battery:");
  u8g2.setFont(u8g2_font_ncenB14_tr);
  u8g2.setCursor(68, 56);
  u8g2.print(percentage2);
  u8g2.print("%");

  // Update the display
  u8g2.sendBuffer();
}


/**
   Setup function that runs once at the start of the program.
*/
void setup()
{
  // Initialize the serial communication
  Serial.begin(57600);

  // Set the LED pins as output
  pinMode(ledPin1, OUTPUT);
  pinMode(ledPin2, OUTPUT);
  // Set the button pin as input with internal pull-up resistor
  pinMode(buttonPin, INPUT_PULLUP);

  // Attach an interrupt to the button pin
  attachInterrupt(digitalPinToInterrupt(buttonPin), handleButtonPress, FALLING);

  // Initialize the SSD1306 display
  u8g2.begin();
  u8g2.clearBuffer();
  u8g2.sendBuffer();

  // Set initial value of ledPin2 to HIGH
  digitalWrite(ledPin2, HIGH);
}

/**
   Loop function that runs repeatedly after the setup function.
*/

void loop(){
 handleButtonPress();
 pedaloutPut();
 batteryState();
 timerOledclear();
}