#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

int echoPin =A0;
int trigPin =A1;

int offset = 2;

char keys[4][3] = {
  {'1','2','3'},
  {'4','5','6'},
  {'7','8','9'},
  {'*','0','#'}
};
byte _R[4]   = {9, 8, 7, 6};
byte _C[3] = {5, 4, 3};
char key;
String rx;
int count;
int radius,height,length,width;
unsigned long maxVolume,volume;
bool Mode =0; // 0 cubic   1 cylyndric
Keypad keypad = Keypad(makeKeymap(keys),_R,_C,4,3);

LiquidCrystal_I2C lcd(0x27,16,2);

void setup() {
  lcd.init();
  lcd.backlight();
  lcd.clear();
  pinMode(trigPin, OUTPUT);
  wizard();
}

void loop() {
  if(Mode){
    volume = constrain(height-distance(),0,400);
    volume = (pow(radius,2)*3.14)*volume/1000;
  }else{
    volume = constrain(height-distance(),0,400);
    volume = ((length/100)*(width/100)*(volume/100))*1000;
  }
  lcd.setCursor(0,1);
  lcd.print(volume);
  lcd.print(" L  ");
  lcd.setCursor(10,1);
  lcd.print(floor((volume*100)/maxVolume),0);
  lcd.print(" %  ");
  delay(200);
}

void wizard(){
  lcd.clear();
  lcd.print("1 pour Cubic");
  lcd.setCursor(0,1);
  lcd.print("2 pour Cylyndric");
  do{
    key = keypad.waitForKey();
  }while(key != '1' and  key != '2');
  if(key=='1'){
    Mode = 0;
    lcd.clear();
    lcd.print("Cubic");
    lcd.setCursor(0,1);
    lcd.print("Length:    cm");
    readKeypad();
    length = rx.toInt();
    lcd.setCursor(0,1);
    lcd.print("Width :    cm");
    readKeypad();
    width = rx.toInt();
    lcd.setCursor(0,1);
    lcd.print("Height:    cm");
    readKeypad();
    height = rx.toInt();
    maxVolume = ((length/100)*(width/100)*(height/100))*1000;
    lcd.clear();
    lcd.print("Max Volume:");
    lcd.setCursor(0,1);
    lcd.print(maxVolume);
    lcd.print(" L");
  }else{
    Mode=1;
    lcd.clear();
    lcd.print("cylender");
    lcd.setCursor(0,1);
    lcd.print("Radius:    cm");
    readKeypad();
    radius = rx.toInt();
    lcd.setCursor(0,1);
    lcd.print("Height:    cm");
    readKeypad();
    height = rx.toInt();
    maxVolume = (pow(radius,2)*3.14)*height/1000;
    lcd.clear();
    lcd.print("Max Volume:");
    lcd.setCursor(0,1);
    lcd.print(maxVolume);
    lcd.print(" L");
  }
  delay(3000);
  lcd.clear();
  lcd.setCursor(0,0);
  lcd.print("Volume (litre):");
}
      
float distance(){
  digitalWrite(trigPin, 0);
  delayMicroseconds(2);
  digitalWrite(trigPin, 1);
  delayMicroseconds(10);
  digitalWrite(trigPin, 0);
  long duration = pulseIn(echoPin, 1);
  return((duration*.0343)/2)-offset;
}

void readKeypad(){
  count=0;
  rx="   ";
  while(1){
    key = keypad.waitForKey();
    if(key=='#')break;
    if(key=='*'){
      if(count>0)count--;
      rx[count]=' ';
    }else if(count<3){
      rx[count]=key;
      count++;
    }
    lcd.setCursor(8,1);
    lcd.print(rx);
  }
}