#define F_CPU 16000000UL
#include <inttypes.h>
#include <avr/io.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#define SPI_PORT PORTB
#define SPI_DDR DDRB
#define SPI_SS 2
#define SPI_MOSI 3
#define SPI_MISO 4
#define SPI_SCK 5

#define BUTTON (PINB & (1 << PINB0)) //Pin B0

#define NUMBEROFSCREENS 3

//SCL - PB5 - Pin 13
//MOSI - PB4 - Pin 11
//SS - PB2 - Pin 10

void initSPI0(void)
{
	/* Set SS, MOSI and SCK output, all others input */
	SPI_DDR = (1<<SPI_SS) | (1<<SPI_MOSI) | (1<<SPI_SCK);
	/* Enable SPI, Master, set clock rate fck/128 */
	SPCR = (1<<SPE) | (1<<MSTR) | (1<<SPR1) | (1<<SPR0);
}

void SPI_Master_Transceiver(uint16_t data)
{
	SPI_PORT &= ~(1<<SPI_SS); // Pull Slave_Select low

	SPDR = data >> 8; // Start transmission of first byte
	while( !(SPSR & (1<<SPIF)) );// Wait for transmission complete
	SPDR = (uint8_t)data; // Start transmission of second byte
	while( !(SPSR & (1<<SPIF)) );// Wait for transmission complete

	SPI_PORT |= (1<<SPI_SS); // Pull Slave Select High
}

uint8_t display[24];

/*
uint8_t display[24] = {//agp
	0b00000000,
	0b00111100,
	0b01100110,
	0b01100110,
	0b01111110,
	0b01100110,
	0b01100110,
	0b01100110,

	0B00000000,
	0B00111100,
	0B01000010,
	0B01000000,
	0B01001110,
	0B01000010,
	0B01000010,
	0B00111100,

	0B0000000,
	0B1111000,
	0B1000100,
	0B1000100,
	0B1111000,
	0B1000000,
	0B1000000,
	0B1000000};
*/

uint8_t smile[] = {
0,0,0,0,0,0,0,0,
0b00111100,
0b01111110,
0b11011011,
0b11111111,
0b11011011,
0b01111110,
0b00111100,
0,0,0,0,0,0,0,0};

uint8_t frown[] = {
0,0,0,0,0,0,0,0,
0b00111100,
0b01111110,
0b11011011,
0b11111111,
0b11000011,
0b01111101,
0b00111100,
0,0,0,0,0,0,0,0};


void updateMatrix() //function to put what's in display[] on the LED display
{
	//loop through each row, then send it to the matrixes
	for (char i=0;i<8;i++)
	{
		unsigned long long column;//a place to store the column of the matrix that we're currently working with
		for (char j=(sizeof display)-1;j >= 0;j--)//Have j count down not up to reverse the row before it's sent
		{
			column = column << 1; //shift left 1
			column = column | ((display[j] >> i) & 1);//put the ith bit of display[j] in the lsb of row
		}

		//column is done, now send it over SPI
		SPI_PORT &= ~(1<<SPI_SS); // Pull Slave_Select low

		for (char k=0;k<NUMBEROFSCREENS;k++)//repeat based on number of matrices attached
		{
			SPDR = i+1;//send column number to be updated
			while( !(SPSR & (1<<SPIF)) );// Wait for transmission complete
			SPDR = column >> 8*k;//send the first bit of "row" (8*0), then the second (8*1), etc.
			while( !(SPSR & (1<<SPIF)) );// Wait for transmission complete
		}

		SPI_PORT |= (1<<SPI_SS); // Pull Slave Select High
	}
}

void setup() 
{
	//initalizations
	Serial.begin(9600);
	initSPI0();
	updateMatrix();

	DDRB &= ~(1 << DDB0);//set pin B0 (the pushbutton) as an input

}


char row = 23;
unsigned int currentRow = 0b1111000000;
char isGoingRight = 1;
char oneShotFlag = 0;
char restartFlag = 0;
void loop() 
{
	if (BUTTON)
	{
		if (!oneShotFlag)//one-shot handling
		{
			if (row != 23)//hande the case where the first row just gets placed
			{
				//AND current row with the one below
				display[row] = display[row+1] & display[row];
				updateMatrix();//send to display
			}

			if (!display[row] || !row)//handle winning + loosing
			{
				for (char i=0;i<6;i++)//flash screen
				{
					for (char j=0;j < (sizeof display);j++) display[j] = ~display[j];//invert display
					updateMatrix();//send to display
					_delay_ms(500);
				}
				//frown or smile
				if (!display[row]) for (char i=0;i < (sizeof display);i++) display[i] = frown[i]; //handle loosing
				else for (char i=0;i < (sizeof display);i++) display[i] = smile[i]; //handle winning

				updateMatrix();//send to display
				_delay_ms(5000000000000000);

				restartFlag = 1;//set flag to restart the game
			}

			if (!restartFlag)
			{
				//count how many ones there are in the row so the length of the cursor in the next row will be the same
				char countOfOnes = 0;
				for (char i=0;i<8;i++) if ((display[row]>>i)&1) countOfOnes++;

				row--;//move up one row

				//find where the stack is so we can put the cursor there
				char whereToPutCursor = 4;
				for (char i=0;i<8;i++) if (((int)pow(2,countOfOnes)>>i)&1) whereToPutCursor++;

				//(int)pow(2,countOfOnes) -> create int with countOfOnes 1s
				//shift by whereToPutCursor so it's above the previous row
				currentRow = (int)pow(2,countOfOnes) << whereToPutCursor;
			}
			else //need to reset everything
			{
			  memset(display, 0, sizeof(display));//blank display
			 	row = 23;
				currentRow = 0b1111000000;
				isGoingRight = 1;
				restartFlag = 0;
			}
		}
		oneShotFlag=1;//one-shot handling
	}
	else oneShotFlag=0;//one-shot handling

	//if lsb or msb is 1, need to switch directions 
	if ((currentRow & 0b10) || (currentRow & 0b0100000000000000)) isGoingRight = !isGoingRight;

	//shift left or right, depending
	if (isGoingRight) currentRow = currentRow >> 1;
	else currentRow = currentRow << 1;

	display[row] = (uint8_t)(currentRow >> 4);//update array
	updateMatrix();//send to display

	_delay_ms(100);


}