#include <Adafruit_NeoPixel.h>

#define PIN_LED 2
#define NUMPIXELS 4 

//LED-Key-Zuordnung
const uint8_t key[] = { 4, A2, 12, 7 };
const uint8_t led[] = { 2, 3, 1, 0 };


Adafruit_NeoPixel pixels(NUMPIXELS, PIN_LED, NEO_GRB + NEO_KHZ800);


//Funktion für LED aktiver/inaktiver Zustand
void set_led(int l, bool state) {
    uint32_t colors_en[] = { pixels.Color(0, 255, 0), pixels.Color(255, 0, 0), pixels.Color(0, 0, 255), pixels.Color(255, 255, 0) };
    uint32_t colors_dis[] = { pixels.Color(0, 50, 0), pixels.Color(50, 0, 0), pixels.Color(0, 0, 50), pixels.Color(25, 25, 0) };

    if(state) {
      pixels.setPixelColor(led[l], colors_en[l]);
    } else pixels.setPixelColor(led[l], colors_dis[l]);

    pixels.show();
}


void setup() {
	pixels.begin();

	randomSeed(analogRead(0)+analogRead(1)+analogRead(3)+analogRead(4));

	//Eingänge
	pinMode(key[0], INPUT); 
	pinMode(key[1], INPUT); 
	pinMode(key[2], INPUT); 
	pinMode(key[3], INPUT); 

	//Pullup
	digitalWrite(key[0], HIGH);
	digitalWrite(key[1], HIGH);
	digitalWrite(key[2], HIGH);
	digitalWrite(key[3], HIGH);
}

//Zustände
enum { intro, fail, input, show };
int state = intro;

int intro_ct = 50;
int error_red_val = 255;

uint8_t valuehistory[255];
uint8_t valuehistory_position = 0;

unsigned long timer1 = millis();

void loop() {
	//Introanimation
	if(state == intro) {
		int i = random(4);

		set_led(0, i==0);
		set_led(1, i==1);
		set_led(2, i==2);
		set_led(3, i==3);

		delay(100);

		intro_ct--;
		if(intro_ct == 0) state = fail; 
	}

	//Rot Blinken
	if(state == fail) {
		//Animation
		if(millis()-timer1 > 100) {
			error_red_val = (error_red_val==255) ? 50 : 255;

			timer1 = millis();
		}
		for (uint8_t i = 0; i < 4; i++)
		{
			pixels.setPixelColor(i, pixels.Color(error_red_val, 0, 0));
		}
		pixels.show();

		//reset saved values
		valuehistory_position = 0;

		//Tansaktion
		if(!digitalRead(key[0])||!digitalRead(key[1])||!digitalRead(key[2])||!digitalRead(key[3])) {
			state = show;

			set_led(0, false);
			set_led(1, false);
			set_led(2, false);
			set_led(3, false);

			delay(1000);
		}
	}

	//Abspielen
	if(state == show) {
		valuehistory[valuehistory_position] = random(4);

		for (uint8_t i = 0; i <= valuehistory_position; i++)
		{
			set_led(0, valuehistory[i]==0);
			set_led(1, valuehistory[i]==1);
			set_led(2, valuehistory[i]==2);
			set_led(3, valuehistory[i]==3);

			delay(500);

			set_led(0, false);
			set_led(1, false);
			set_led(2, false);
			set_led(3, false);

			delay(500);
		}

		state = input;
	}

	//Eingabe
	if(state == input) {
		for(uint8_t i = 0; i <= valuehistory_position; i++) {
			while(digitalRead(key[0])&&digitalRead(key[1])&&digitalRead(key[2])&&digitalRead(key[3]));

			bool correct = (valuehistory[i]==0&&!digitalRead(key[0])) || (valuehistory[i]==1&&!digitalRead(key[1])) || (valuehistory[i]==2&&!digitalRead(key[2])) || (valuehistory[i]==3&&!digitalRead(key[3]));

			set_led(0, !digitalRead(key[0]));
			set_led(1, !digitalRead(key[1]));
			set_led(2, !digitalRead(key[2]));
			set_led(3, !digitalRead(key[3]));

			delay(500);

			set_led(0, false);
			set_led(1, false);
			set_led(2, false);
			set_led(3, false);


			if(correct) {
				state = show;
				delay(100);
			} else {
				state = fail;
				break;
			}
		}

		delay(1000);

		valuehistory_position++;
	}  
}