#include <avr/io.h>		//standard AVR header
#define F_CPU 16000000UL	// THE CPU FREQUENCY
#include <util/delay.h>		//delay header
#include <avr/interrupt.h>      //interrupt header
#include <stdlib.h> 

#define LCD_DPRT PORTD		//LCD DATA PORT
#define LCD_DDDR DDRD		//LCD DATA DDR
#define LCD_DPIN PIND		//LCD DATA PIN
#define LCD_CPRT PORTB		//LCD COMMANDS PORT
#define LCD_CDDR DDRB		//LCD COMMANDS DDR
#define LCD_CPIN PINB		//LCD COMMANDS PIN
#define LCD_RS 0		//LCD RS
#define LCD_EN 1		//LCD EN
				
// Define your buffer sizes
#define SERIAL_BUFFER_SIZE 20
#define NOTES_BUFFER_SIZE 20

// Global variables
char serialBuffer[SERIAL_BUFFER_SIZE];
char notesBuffer[NOTES_BUFFER_SIZE];
int serialIndex = 0;
int notesIndex = 0;
volatile int buttonState = 0; // Holds the state of all buttons
			      //
void lcd_putValue(unsigned char val)
{
	LCD_DPRT &= 0x0F;
	LCD_DPRT |= (val & 0xF0);	//send cmnd to data port
	LCD_CPRT |= (1 << LCD_EN);	//EN = 1 for H-to-L pulse
	_delay_us(1);		//wait to make enable wide
	LCD_CPRT &= ~(1 << LCD_EN);	//EN = 0 for H-to-L pulse
	_delay_us(100);		//wait to make enable wide
	LCD_DPRT &= 0x0F;
	LCD_DPRT |= val << 4;	//send cmnd to data port
	LCD_CPRT |= (1 << LCD_EN);	//EN = 1 for H-to-L pulse
	_delay_us(1);		//wait to make enable wide
	LCD_CPRT &= ~(1 << LCD_EN);	//EN = 0 for H-to-L pulse
	_delay_us(100);		//wait to make enable wide
}

//*******************************************************
void lcdCommand(unsigned char cmnd)
{
	LCD_CPRT &= ~(1 << LCD_RS);	//RS = 0 for command
	lcd_putValue(cmnd);
}

//*******************************************************
void lcdData(unsigned char data)
{
	LCD_CPRT |= (1 << LCD_RS);	//RS = 1 for data
	lcd_putValue(data);
}

void lcd_clear()
{
	lcdCommand(0x01);
	_delay_us(1700);
}

void lcd_showCursor()
{
	lcdCommand(0x0E);
	_delay_us(50);
}

void lcd_hideCursor()
{
	lcdCommand(0x0C);
	_delay_us(50);
}

//*******************************************************
void lcd_init()
{
	LCD_DDDR |= 0xF0;
	LCD_CDDR |= (1 << LCD_RS) | (1 << LCD_EN);
	LCD_CPRT &= ~(1 << LCD_EN);	//LCD_EN = 0
	_delay_us(2000);	//wait for init.
	lcdCommand(0x33);	//send $33 for init.
	lcdCommand(0x32);	//send $32 for init
	lcdCommand(0x28);	//init. LCD 2 line,5*7 matrix
	lcdCommand(0x0e);	//display on, cursor on
	lcdCommand(0x06);	//shift cursor right
	lcd_clear();
}

//*******************************************************
void lcd_gotoxy(unsigned char x, unsigned char y)
{
	unsigned char firstCharAdr[] = { 0x80, 0xC0, 0x94, 0xD4 };	//Table 12-4
	lcdCommand(firstCharAdr[y - 1] + x - 1);
	_delay_us(100);
}

//*******************************************************
void lcd_print(char *str)
{
	unsigned char i = 0;
	while (str[i] != 0)	//while it is not end of string
	{
		lcdData(str[i]);
		i++;
	}
}

char getSerialData() {
    // Read serial data and return it
    return ' ';
}

char getNote() {
    // Read notes data and return it
    return ' ';
}

void setup() {
    // Initialize Serial communication
    // Initialize LCD
    // Initialize buttons as inputs
    // Set pins A4 and A5 as inputs with pull-up resistors enabled
    DDRC &= ~((1 << DDC4) | (1 << DDC5));
    PORTC |= (1 << PORTC4) | (1 << PORTC5);

    // Enable Pin Change Interrupt on pins PC4 and PC5
    PCMSK1 |= (1 << PCINT12) | (1 << PCINT13); // Enable PCINT for pins PC4 and PC5
    PCICR |= (1 << PCIE1); // Enable Pin Change Interrupt 1
    sei(); // Enable global interrupts
}

ISR(PCINT1_vect) {
    // Update button state when any pin changes state
    for (unsigned char i = 4; i <= 5; i++) {
	    if (PINC & (1 << i)) {
		    if(buttonState == 0) 
		    	buttonState = i;
		    else
			buttonState = 0;
		    break;
	    }
    }
}

void displayNotes() {
    char circularBuffer[16];
    static int bufferIndex = 0;

    lcd_clear();
    lcd_gotoxy(6, 2);
    lcd_print("PLAYING");
    _delay_ms(1000);
    lcd_clear();
    _delay_ms(1000);
    while (buttonState == 4) {
        char randomValue = '0' + (rand() % 10);

        if (bufferIndex == 16) {
            // Remove the first value and shift other values down
            for (int i = 0; i < 16 - 1; i++) {
                circularBuffer[i] = circularBuffer[i + 1];
            }
            // Add the new value at the end
            circularBuffer[16 - 1] = randomValue;
        } else {
            // Add the new value to the buffer
            circularBuffer[bufferIndex] = randomValue;
	    bufferIndex++;
        }

        lcd_clear();
        for (int i = 0; i <= bufferIndex - 1; i++) {
            char singleChar[2] = {circularBuffer[i], '\0'};
	    lcd_gotoxy(17-bufferIndex+i ,1);
	    lcd_print(singleChar); // Print the single character
	    lcd_gotoxy(6,2);
	    lcd_print("PLAYING");
        }

        _delay_ms(1000);
    }
    bufferIndex = 0;
    lcd_clear();
}



void displaySerialData() {
    char circularBuffer[16];
    static int bufferIndex = 0;
    lcd_clear();
    lcd_gotoxy(3, 2);
    lcd_print("RECORDING");
    _delay_ms(1000);
    lcd_clear();
    _delay_ms(1000);
    while (buttonState == 5) {
        char randomValue = '0' + (rand() % 10);

        if (bufferIndex == 16) {
            // Remove the first value and shift other values down
            for (int i = 0; i < 16 - 1; i++) {
                circularBuffer[i] = circularBuffer[i + 1];
            }
            // Add the new value at the end
            circularBuffer[16 - 1] = randomValue;
        } else {
            // Add the new value to the buffer
            circularBuffer[bufferIndex] = randomValue;
	    bufferIndex++;
        }
	
        lcd_clear();
	lcd_gotoxy(1,1);
        for (int i = 0; i <= bufferIndex-1; i++) {
            char singleChar[2] = {circularBuffer[bufferIndex- 1 - i], '\0'};
	    lcd_gotoxy(i+1,1);
	    lcd_print(singleChar); // Print the single character
	    lcd_gotoxy(3,2);
	    lcd_print("RECORDING");
        }
	
        _delay_ms(1000);
    }
    bufferIndex = 0;
    lcd_clear();
}

//*******************************************************
int main(void) {
	lcd_init();
	lcd_hideCursor();
	setup();
	lcd_clear();
    	while (1) {
		// Check button state and perform actions accordingly
        	if (buttonState == 5) {
			displaySerialData();

       		} else if (buttonState == 4) {
			displayNotes();
        	} 
		else { 
			lcd_gotoxy(6,2);
			lcd_print("PIANO");
			_delay_ms(1000);
		}
	}
    	return 0;
}