#define F_CPU 16000000UL
#include <avr/io.h>
#include <util/delay.h>
// PORT DEFINES
#define LED_Direction DDRC
#define LED_PORT PORTC
#define DIGIT_Direction DDRB
#define DIGIT_PORT PORTB
#define BUTTON_Direction DDRA
#define BUTTON_Vcc PORTA
#define BUTTON_PORT PINA
#define STATE_NONE_PRESSED 0x00
#define STATE_SOME_PRESSED 0xff
int main(void){ // setting ports as inputs and output
    LED_Direction |= 0xff;
    LED_PORT = 0xff;
    DIGIT_Direction |= 0xff;
    DIGIT_PORT = 0xff;
    BUTTON_Direction |= 0x00;
    BUTTON_Vcc = 0xff;
    BUTTON_PORT = 0xff;

    char symbols[]={0xC0,0xF9,0xA4,0xB0,0x99,0x92,0x82,0xF8,0x80,0x90}; // 0-9 number to 7segment display translation table
    char yes[] = {0x91, 0x86,0x92,0xff}; // 'yes' in 7seg
    char no[] = {0xC8, 0xC0,0xff,0xff}; // 'no' in 7seg
    char pin[]={0,0,0,0}; // output values: 'yes', 'no', 'no vote', 'invalid vote (yes and no)'
    char votes[7] = {}; //votes of every button (1=yes, 2=no, 3=invalid, 0=no-vote)
    char buttons = 0x00;
    char button_state = STATE_NONE_PRESSED;
    char key[8];

    for(int i=0; i<8; i++){
        key[i] = ~(1<<i);
    }
    int state = 0;
    int allow = 0;
    int yess= 0;
    int nos = 0;
    while(1) { //output clear
        pin[0] = 0;
        pin[1] = 0;
        pin[2] = 0;
        pin[3] = 0;
        for(int j = 6; j >= 0 ; j--){  //count votes
            if(votes[j] == 0){
                pin[2]++;
            }
            if(votes[j] == 1){
                pin[0]++;
            }
            if(votes[j] == 2){
                pin[1]++;
            }
            if(votes[j] == 3){
                pin[3]++;
            }
        } //output in 7segment
        if(state < 2){ //if voting in pending
            for(int i=0;i<4;i++){  //for every digit
                if(state == 0){ //state 0 = voting for yes
                    if(i < 3){
                    LED_PORT = yes[i];
                    }else{
                    LED_PORT = symbols[yess];
                    }
                }
                if(state == 1){ //state 1 = voting for no
                    if(i < 3){
                        LED_PORT = no[i];
                        }else{
                        LED_PORT = symbols[nos];
                    }
                }
                DIGIT_PORT = ~(0x01 << i); //shift 1bit to output on another digit
                _delay_ms(4);
            }
        }else{
            for(int i=0;i<4;i++){ //if state 2 = end of voting
                if(state == 2){
                    LED_PORT = symbols[pin[i]];
                }
                    DIGIT_PORT = ~(0x01 << i);
                    _delay_ms(4);
                }
        }  //voting
        buttons = BUTTON_PORT;
        if(button_state == STATE_NONE_PRESSED){
            if(buttons != 0xff){
                button_state = STATE_SOME_PRESSED;
                if(state < 2){
                    for(int i = 6; i >= 0 ; i--){
                        if(state){ // if state != 0  (voting for no)
                            if(buttons == key[i]){  //if key 1-6 pressed -> vote
                                if(votes[i] > 1){
                                    votes[i] -= 2;
                                    nos--;
                                } else {
                                    votes[i] += 2;
                                    nos++;
                                }
                                allow = 1;
                            }
                            if(buttons == key[7] && allow == 1){ //if key 7 pressed -> change state
                                state = 2;
                            }
                        }else{ //if state == 0 (voting for yes)
                            if(buttons == key[i]){  //if key 1-6 pressed -> vote
                                if(votes[i] == 1){
                                    votes[i] = 0;
                                    yess--;
                                } else{
                                    votes[i] = 1;
                                    yess++;
                                }
                            }
                            if(buttons == key[7]){ //if key 7 pressed -> change state
                                state = 1;
                            }
                        }
                    }
                }
            }
        }
        if(button_state == STATE_SOME_PRESSED){ // Wait for buttons to stop being pressed
            if(buttons == 0xff){
                button_state = STATE_NONE_PRESSED;
            }
        }
    }
}