#include <AccelStepper.h>
#include <LiquidCrystal.h>

#define step 2
#define dir 3
#define trig 7
#define echo 6
#define rs 8
#define en 9
#define d4 10
#define d5 11
#define d6 12
#define d7 13

LiquidCrystal lcd(rs, en, d4, d5, d6, d7);
AccelStepper stepper(AccelStepper::DRIVER, step, dir);

int doorpos = 0;
int entry_count = 0;
const int threshold_dist = 30;

void setup() {
    lcd.begin(16, 2);
    lcd.print("Door: Closed");
    pinMode(trig, OUTPUT);
    pinMode(echo, INPUT);
    stepper.setMaxSpeed(1000);
    stepper.setAcceleration(500);
    Serial1.begin(115200);
    Serial1.println("System Initialized");
}

void loop() {
    long distance = avg_dist();
    Serial1.print("Distance: ");
    Serial1.println(distance);

    if (distance < threshold_dist && doorpos == 0) {
        open();
    } else if (distance >= threshold_dist && doorpos == 1) {
        close();
    }
    delay(200);
}

long avg_dist() {
    long tot_dist = 0;
    int readings = 5;
    for (int i = 0; i < readings; i++) {
        long duration;
        digitalWrite(trig, LOW);
        delayMicroseconds(2);
        digitalWrite(trig, HIGH);
        delayMicroseconds(10);
        digitalWrite(trig, LOW);
        duration = pulseIn(echo, HIGH);
        long distance = (duration * 0.034) / 2;
        tot_dist += distance;
        delay(50);
    }
    return tot_dist / readings;
}

void open() {
    stepper.moveTo(200);
    stepper.runToPosition();
    doorpos = 1;
    entry_count++;
    display_stat();
}

void close() {
    stepper.moveTo(0);
    stepper.runToPosition();
    doorpos = 0;
    display_stat();
}

void display_stat() {
    lcd.clear();
    lcd.print("Door: ");
    if (doorpos == 1) {
        lcd.print("Open");
    } else {
        lcd.print("Closed");
    }
    lcd.setCursor(0, 1);
    lcd.print("Entries: ");
    lcd.print(entry_count);
}