#include <LiquidCrystal.h>
#include <EEPROM.h>

// THIS DOES NOT KEEP TIME, AND HAS NO WAY OF KEEPING TIME! THIS CODE DOES NOT SUPPORT TIME AS A WAY OF KNOWING HOW LATE IT IS IN A DAY!

LiquidCrystal lcd(3, 4, 5, 6, 7, 8);

/*
  A0 - exit (left)
  A1 - enter (right)
  A2 - up
  A3 - down
*/

// ↓↓↓ Configs ↓↓↓
unsigned int wheelCircum = 2194;    // wheel circumference in millimeters (changeable in settings)
byte configh = 16;  // abbbbbbb, a → unit, (0 - km/h, 1 - mi/h,),, b → 7-bit number (number of seconds before speed zeroes itself)
byte configl = 50;  // low byte of configs, one 8-bit number (refresh time in hundredths of a second)

int zerotime = 0;  // number of seconds before speed gets zeroed out
byte units = 0;  // kilometers ( + per hour) as default
byte mover = 0;


// ↑↑↑ Configs ↑↑↑

float time = 1000000.00;
unsigned long present = 0;
unsigned long present2 = 0;
unsigned long present4 = 0;
unsigned long past2 = 0;
unsigned long past4 = 0;
unsigned long past5 = 0;
unsigned long ridetime = 0;  // total ride time in ms (will not count first 10 wheel rotations to get stable data)
unsigned long ridetime2 = 0;  // total ride time in seconds (will not count first 10 wheel rotations to get stable data)

float kmph = 0;
float kmphShown = 0;
float kmphmax = 0;  // maximum speed
float mph = 0;
float mphmax = 0;

float dist = 0;
float velocity = 0;
float maxvel = 0;

String veldelim = "";
String distdelim = "";

float km = 0;
float mi = 0;

float intermid = 0;
float intermid2 = 0;
float intermid3 = 0;
float intermid4 = 0;
float intermid5 = 0;
unsigned long count = 0;
unsigned long count2 = 0;

int isinmenu = 0;
int page = 0;
int subpage = 0;

int arwhorpos = 0;  // horizontal position of arrow in number editing

unsigned int arwvertpos = 0;  // arrow vertical position in menu item selection

int incrementer = 1;

void setup() {
  int iswritten = 0;
  EEPROM.get(0, iswritten);

if(iswritten <= 2) {
  EEPROM.put(0, 4);
  EEPROM.put(2, wheelCircum);
  EEPROM.write(4, configh);
  EEPROM.write(5, configl);
} else {
  EEPROM.get(2, wheelCircum);
  configh = EEPROM.read(4);
  configl = EEPROM.read(5);
}

units = configh & 128;

  zerotime = configh & 127;

  pinMode(3, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(2, INPUT_PULLUP);       // Magnet Sensor

  pinMode(A0, INPUT_PULLUP);
  pinMode(A1, INPUT_PULLUP);
  pinMode(A2, INPUT_PULLUP);
  pinMode(A3, INPUT_PULLUP);

  delay(250);

  lcd.begin(20, 4);

  delay(250);

  lcd.print("New and improved");
  lcd.setCursor(0, 1);
  lcd.print("Bicycle speedometer");
  lcd.setCursor(0, 2);
  lcd.print("With more features!");
  lcd.setCursor(0, 3);
  lcd.print("Now has menus!");
  delay(3000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Very adjustable!");
  lcd.setCursor(0, 1);
  lcd.print("So many settings!");
  lcd.setCursor(0, 2);
  lcd.print("A great improvement");
  lcd.setCursor(0, 3);
  lcd.print("over the old version");

  attachInterrupt(digitalPinToInterrupt(2), zeroing, FALLING);

  delay(3200);

  lcd.clear();

}

void zeroing () {
  count = count + 1;
  time = present2 - past2;
  past2 = present2;
  count2 = 0;
  ridetime = ridetime + time;
}

void loop() {

  if((!(units))) {
    velocity = kmphShown;
    veldelim = "km/hr";
    distdelim = "km";
    maxvel = kmphmax;
    dist = km;
  }

  if(units) {
    velocity = mph;
    veldelim = "mi/hr";
    distdelim = "mi";
    maxvel = mphmax;
    dist = mi;
  }

if(isinmenu < 2 && digitalRead(A1) == LOW) {  // if we are less than 3 menus deep and enter is pressed
    delay(250);
    isinmenu = isinmenu + 1;
  }

  if(isinmenu > 0 && digitalRead(A0) == LOW) {
    delay(250);

    if(isinmenu <= 1) {
      EEPROM.put(2, wheelCircum);
      configh = configh & 128;
      configh = configh | zerotime;
      EEPROM.write(4, configh);
      EEPROM.write(5, configl);
    }

    isinmenu = isinmenu - 1;
  }

if(isinmenu == 1) {

  arwvertpos = arwvertpos % 4;

    if((!(digitalRead(A3)))) {
      delay(250);
      arwvertpos = arwvertpos + 1;
    }

    if((!(digitalRead(A2)))) {
      delay(250);
      arwvertpos = arwvertpos - 1;
    }

  }

  if(isinmenu == 2) {

    switch(arwvertpos) {

      case 0:
        if((!(digitalRead(A3) && digitalRead(A2)))) {
          delay(250);
          units = units + 1;
          units = units % 2;

          if(units) {
            configh = configh | 128;
          } else {
            configh = configh & 127;
          }
          
        }
        break;

      case 1:
        if(!(digitalRead(A2))) {
          delay(250);
          wheelCircum = wheelCircum + incrementer;
        }
        if(!(digitalRead(A3))) {
          delay(250);
          wheelCircum = wheelCircum - incrementer;
        }
        if(!(digitalRead(A1))) {
          arwhorpos = arwhorpos + 1;
          arwhorpos = arwhorpos % 4;
          delay(250);
        }
        break;

      case 2:    
        if(!(digitalRead(A2))) {
          delay(250);
          zerotime = zerotime + incrementer;
        }

        if(!(digitalRead(A3))) {
          delay(250);
          zerotime = zerotime - incrementer;
        }

        if(!(digitalRead(A1))) {
          arwhorpos = arwhorpos + 1;
          arwhorpos = arwhorpos % 4;
          delay(250);
        }
          break;

          case 3:    
        if(!(digitalRead(A2))) {
          delay(250);
          configl = configl + incrementer;
        }

        if(!(digitalRead(A3))) {
          delay(250);
          configl = configl - incrementer;
        }

        if(!(digitalRead(A1))) {
          arwhorpos = arwhorpos + 1;
          arwhorpos = arwhorpos % 4;
          delay(250);
        }
          break;

    }

  }

  if(present - past5 > (configl * 10)) {
    lcd.clear();
    past5 = present;

  if(isinmenu == 1) {
    lcd.print(" System of units    ");  // row 1
    lcd.print(" Zeroing time       ");  // row 3
    lcd.print(" Wheel circumference");  // row 2
    lcd.print(" LCD Refresh time   ");  // row 4
    lcd.setCursor(0, arwvertpos);
    lcd.print(">");
  }

  if(isinmenu == 2) {

    switch(arwvertpos) {

      case 0:
        lcd.print(" Measurement units: ");
        lcd.setCursor(1, 2);
        if((!(units))) {
          lcd.print("Metric    (km, /hr)");
        } else {
          lcd.print("Imperial  (mi, /hr)");
        }
        break;

      case 1:
      if(wheelCircum >= 1000) {mover = 3;}
      if(wheelCircum < 1000 && wheelCircum >= 100) {mover = 4;}
      if(wheelCircum < 100 && wheelCircum >= 10) {mover = 5;}
      if(wheelCircum < 10) {mover = 6;}
        lcd.setCursor(0, 0);
        lcd.print("Wheel circumference:");
        lcd.setCursor(mover, 2);
        lcd.print(wheelCircum);
        lcd.setCursor((arwhorpos + 3), 3);
        lcd.write(94);
        lcd.setCursor(9, 2);
        lcd.print("millimeters");
        break;

      case 2:
        if(zerotime >= 1000) {mover = 3;}
        if(zerotime < 1000 && zerotime >= 100) {mover = 4;}
        if(zerotime < 100 && zerotime >= 10) {mover = 5;}
        if(zerotime < 10) {mover = 6;}
        lcd.setCursor(0, 0);
        lcd.print("Zeroing time:");
        lcd.setCursor(mover, 2);
        lcd.print(zerotime);
        lcd.setCursor((arwhorpos + 3), 3);
        lcd.write(94);
        lcd.setCursor(9, 2);
        lcd.print("seconds");
        break;

      case 3:
        if(configl >= 1000) {mover = 1;}
        if(configl < 1000 && configl >= 100) {mover = 2;}
        if(configl < 100 && configl >= 10) {mover = 3;}
        if(configl < 10) {mover = 4;}
        lcd.setCursor(0, 0);
        lcd.print("LCD Refresh time:");
        lcd.setCursor(mover, 2);
        lcd.print(configl);
        lcd.setCursor((arwhorpos + 1), 3);
        lcd.write(94);
        lcd.setCursor(6, 2);
        lcd.print("1/100ths of 1s");
        break;

    }

  }

  if((!(isinmenu))) {
    lcd.setCursor(0, 0);
    lcd.print("Speed: ");
    lcd.print(velocity);
    lcd.setCursor(15, 0);
    lcd.print(veldelim);
    lcd.setCursor(0, 1);
    lcd.print("Trip: ");
    lcd.print(dist);
    lcd.setCursor(18, 1);
    lcd.print(distdelim);
    lcd.setCursor(0, 2);
    lcd.print("MaxSPD: ");
    lcd.print(maxvel);
    lcd.setCursor(15, 2);
    lcd.print(veldelim);
    lcd.setCursor(0, 3);
    lcd.print("Time:");
    lcd.print(ridetime2);
    lcd.setCursor(13, 3);
    lcd.print("Seconds");
  }

  

  }
/*
lcd.print();
lcd.setCursor(, );
*/
  switch(arwhorpos) {

    case 0:
      incrementer = 1000;
      break;

    case 1:
      incrementer = 100;
      break;

    case 2:
      incrementer = 10;
      break;

    case 3:
      incrementer = 1;
      break;

  }

  ridetime2 = ridetime / 1000;

  if (count <= 9) {
    ridetime = 0;
  }

  mph = kmphShown / 1.609344;
  mphmax = kmphmax / 1.609344;
  mi = km / 1.609344;

  present = millis();
  present2 = millis();
  present4 = millis();

  if (kmphmax <= kmph) {
    kmphmax = kmph;
  }

  intermid5 = wheelCircum * count;
  km = intermid5 / 1000000;

  intermid = 1000 / time;
  intermid2 = intermid * wheelCircum;
  intermid3 = intermid2 * 3600;
  intermid4 = intermid3 / 1000000;
  kmph = intermid4;

  if (present4 - past4 >= 1000) {
    count2 = count2 + 1;
    past4 = present4;
  }

  if (count2 <= zerotime - 1) {
    kmphShown = kmph;
  }

  if (count2 >= zerotime) {
    kmphShown = 0;
  }

}