#include <LiquidCrystal_I2C.h>
#include <Wire.h>
#include <Keypad.h>
#include "HX711.h"

LiquidCrystal_I2C lcd_1(0x27, 16, 2);  // disply configuration

const int ROW_NUM = 4;     // four rows  // keypad configuration
const int COLUMN_NUM = 4;  // four columns
char keys[ROW_NUM][COLUMN_NUM] = {
  { '1', '2', '3', 'A' },
  { '4', '5', '6', 'B' },
  { '7', '8', '9', 'C' },
  { '*', '0', '#', 'D' }
};
byte pin_rows[ROW_NUM] = { 9, 8, 7, 6 };       // connect to the row pinouts of the keypad
byte pin_column[COLUMN_NUM] = { 5, 4, 3, 2 };  // connect to the column pinouts of the keypad
Keypad customKeypad = Keypad(makeKeymap(keys), pin_rows, pin_column, ROW_NUM, COLUMN_NUM);

const int BUZZER_PIN = 10;  // buzzer configuration

#define calibration_factor -7050.0  //This value is obtained using the SparkFun_HX711_Calibration sketch
#define LOADCELL_DOUT_PIN A0
#define LOADCELL_SCK_PIN A1
HX711 scale;

int trigPin = 12;  // TRIG pin // ultrasonic sensor configuration
int echoPin = 11;  // ECHO pin
float duration_us, distance_cm;

// Input buffer string
#define MAXBUF 20
char buf[MAXBUF];
// Pointer to the last string buffer char
byte ptr = 0;
bool PhoneInput = false;
// The final string containing the phone number
char PhoneNo[20];
// The entered age (0=no age entered)
byte Age = 0;
enum  {
  S_Idle,     // defaults to 0
  S_Phone,    // defaults to 1
  S_Age,      // defaults to 2
  S_Gender,   // defaults to 3
  S_Height,   // defaults to 4
  S_Weight,   // defaults to 5
  S_Receipt,  // defaults to 6

 }
  State = S_Idle;
int Scale_Mode = 0;
char customKey = customKeypad.getKey();

void displayscreen() {  // screen saver

  lcd_1.setCursor(4, 0);
  lcd_1.print("*iScale*");
  lcd_1.setCursor(2, 1);
  lcd_1.print("!Your Scale!");
  lcd_1.scrollDisplayLeft();
  delay(200);
  lcd_1.scrollDisplayRight();
}

/*void weight() {  // weight measurement module to be activated later

  Serial.print("Reading: ");
  Serial.print(scale.get_units(), 1);  //scale.get_units() returns a float
  Serial.print(" lbs");                //You can change this to kg but you'll need to refactor the calibration_factor
  Serial.println();
  delay(1000);
  /*if(Scale_Mode != 0){
    State = S_Phone;
  }
  switch (GetKey("CD")) {
    case 'C':
     State = S_Phone; 
      return;
    case 'D':
     State = S_Phone;
      return;
  }*/
//}*/

void weight2() {  // weight measurement module to be activated later

  Serial.print("Reading: ");
  Serial.print(scale.get_units(), 1);  //scale.get_units() returns a float
  Serial.print(" lbs");                //You can change this to kg but you'll need to refactor the calibration_factor
  Serial.println();
  delay(1000);
  State = S_Receipt;
}

void Height() {  // height measurement module
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration_us = pulseIn(echoPin, HIGH);
  distance_cm = 0.017 * duration_us;
  //lcd_1.clear();
  // lcd_1.setCursor(0, 1);
  // lcd_1.print("Height: ");
  // lcd_1.print(distance_cm);
  Serial.print("Height: ");
  Serial.println(distance_cm);
  delay(1000);
  State = S_Weight;
  
}

byte GetKey(const char* Allowed, bool ShowChar = true) {
  byte NumAllowed = strlen(Allowed);
  char customKey = customKeypad.getKey();
  if (customKey != NO_KEY && ptr < MAXBUF - 1) {
    for (byte i = 0; i < NumAllowed; ++i) {
      if (customKey == Allowed[i]) {
        Scale_Mode = 1;
        tone(BUZZER_PIN, 750, 100);  // make a beep sound
        if (ShowChar) {
          // Replace this with LCD print, if needed
          Serial.print(customKey);
        }
        buf[ptr++] = customKey;
        buf[ptr] = 0x0;  // Always end the string with 0x0
        return customKey;
      }
    }
  }
  return NO_KEY;
}

void BufReset() {
  ptr = 0;
  buf[0] = 0x0;
}

void weight3() {  // weight measurement module to be activated later

  switch (GetKey("0CD")) {
    case 'C':
     State = S_Phone; 
      return;
    case 'D':
     State = S_Phone;
      return;   
    case '0':
     State = S_Phone;
      return;    
  }
  Serial.print("Reading: ");
  Serial.print(scale.get_units(), 1);  //scale.get_units() returns a float
  Serial.print(" lbs");                //You can change this to kg but you'll need to refactor the calibration_factor
  Serial.println();
  delay(400);
}

void setup() {
  Serial.begin(9600);
  pinMode(BUZZER_PIN, OUTPUT);

  lcd_1.init();  // initialize the lcd
  lcd_1.init();
  // Print a message to the LCD.
  lcd_1.backlight();

  Serial.println("HX711 scale demo");  // load cell module to be activated
  scale.begin(LOADCELL_DOUT_PIN, LOADCELL_SCK_PIN);
  //scale.set_scale(calibration_factor); //This value is obtained by using the SparkFun_HX711_Calibration sketch
  //scale.tare();

  // Start input
  PhoneInput = true;
  //Serial.print("Enter phone number ending with '#': ");
}

void loop() {
   Height();
  /*// DEBUG ONLY ----------------------
  static int OldState = -1;
  if (State != OldState) {
    OldState = State;
    Serial.print("State: ");
    Serial.println(State);
  }
  // ---------------------------------

  switch (State) {
    case S_Idle:
      weight3();
      //displayscreen();
      //State = S_Weight;
      //State = S_Phone;
      break;
    case S_Phone:
      GetPhone();
      // Move to next state
      //State = S_Age;
      break;
    case S_Age:
      GetAge();
      // Move to next state
      //State = S_Gender;
      break;
    case S_Gender:
      GetGender();
      // Move to next state
      //State = S_Height;
      break;
    case S_Height:
      Height();
      // Move to next state
      //State = S_Weight ;
      break;
    case S_Weight:
      weight2();
      // Move to next state
      /* if (Scale_Mode = 0) {
                     State = S_Idle; }
                else if (Scale_Mode = 1) {
                     State = S_Receipt;
                 }
      // State = S_Receipt;
      break;
    case S_Receipt:
      GetReceipt();
      // Move to next state
      //State = S_Idle;
      Scale_Mode = 0;
      break;
  }*/
}

void GetPhone() {
  switch (GetKey("0123456789#CD")) {
    case '#':
      // Phone end
      strcpy(PhoneNo, buf);
      BufReset();
      Serial.println();
      // Reset buffer
      PhoneInput = false;
      Serial.print("Thank you, entered phone number is: ");
      Serial.println(PhoneNo);
      State = S_Age;
      return;
    case 'C':
      BufReset();
      Serial.println(" *CLEAR*");
      // Send the prompt again
      Serial.print(": ");
      return;
    case 'D':
      BufReset();
      Serial.println(" *RESET*");
      State = S_Idle;
      return;
  }
}

void GetAge() {
  switch (GetKey("0123456789CD")) {
    case 'C':
      BufReset();
      Serial.println(" *CLEAR*");
      // Send the prompt again
      Serial.print(": ");
      return;
    case 'D':
      BufReset();
      Serial.println(" *RESET*");
      // Next state
      //State = S_WAIT;
      State = S_Idle;
      return;
  }
  if (strlen(buf) == 2) {
    // Two digits have been entered!
    //atoi(Age, buf);
    Age = atoi(buf);
    Serial.print("Thank you, your age is: ");
    Serial.println(Age);
    BufReset();
    State = S_Gender;
  }
}

void GetGender() {
  //Serial.println("please select your Gender");
  //Serial.println("Male=* / Female=#");
  switch (GetKey("*#CD")) {
    case 'C':
      BufReset();
      Serial.println(" *CLEAR*");
      // Send the prompt again
      Serial.print(": ");
      return;
    case 'D':
      BufReset();
      Serial.println(" *RESET*");
      State = S_Idle;
      return;
    case '*':
      BufReset();
      Serial.println(" *You are a male*");  // this data to be sent to the computer for furthur calculations
      State = S_Height;
      return;
    case '#':
      BufReset();
      Serial.println(" *You are a female*");
      State = S_Height;
      return;
  }
}

void GetReceipt() {
  switch (GetKey("0*#CD")) {
    case '0':
      State = S_Phone;
      return;
    case 'C':
      BufReset();
      Serial.println(" *CLEAR*");
      // Send the prompt again
      Serial.print(": ");
      return;
    case 'D':
      BufReset();
      Serial.println(" *RESET*");
      State = S_Idle;
      return;
    case '*':
      BufReset();
      Serial.println(" *You choose to print a receipt *");  // this data to be sent to the computer for furthur calculations
      displayscreen();
      State = S_Idle;
      return;
    case '#':
      BufReset();
      Serial.println(" *You choose not to print a receipt*");
      displayscreen();
      State = S_Idle;
      return;
  }
}