/// Include the LiquidCrystal library
#include <LiquidCrystal.h>

// Set up pins for the LCD display (Pin LCD = Pin arduino)
const int RS = 8;
const int EN = 9;
const int d4 = 4;
const int d5 = 5;
const int d6 = 6;
const int d7 = 7;
// const int pin_BL = 10; // arduino pin wired to LCD backlight circuit

// Initialize the library with the numbers of the interface pins
LiquidCrystal lcd(RS, EN, d4, d5, d6, d7);

// define custom characters for arrows
byte upArrow[8] = {
    B00100,
    B01110,
    B11111,
    B00100,
    B00100,
    B00100,
    B00100,
    B00100};

byte downArrow[8] = {
    B00100,
    B00100,
    B00100,
    B00100,
    B00100,
    B11111,
    B01110,
    B00100};

// define some values used by the panel and buttons
int lcd_key = 0;
int adc_key_in = 0;
#define btnRIGHT 0
#define btnUP 1
#define btnDOWN 2
#define btnLEFT 3
#define btnSELECT 4
#define btnNONE 5

// Test Short and long press
unsigned long currentMillis = 0;
const unsigned long SlowDelay = 150;  // Délai entre 2 appuis
const unsigned long FastDelay = 1000; // Délai entre 2 incrémentation lors d'un appui
const unsigned long FastStep = 1000;  // pas d'incrémentation lors d'un appui long
unsigned long LastAction = 0;

// Define constant for the relay pin
const int RELAY = 3;

// Define variables for the menu state
int menu = 0;              // 0: main menu, 1: start test, 2: stop test, 3: configure test
int maxActuations = 10;    // default value for the maximum number of actuations
int currentActuations = 0; // current number of actuations

// Define variable for the relay state
bool relayOn = false;

// Msg Coniguration
char *messagePadded = " LEFT:Config SELECT:Start/Pause ";

void setup()
{

  lcd.createChar(0, upArrow);   // Create UpArrow
  lcd.createChar(1, downArrow); // Create downArrow

  // Set up the LCD's number of columns and rows:
  lcd.begin(16, 2);
  lcd.setCursor(0, 0);

  // Set the relay pin as output
  pinMode(RELAY, OUTPUT);

  // Turn off the relay
  digitalWrite(RELAY, LOW);

  // Display the main menu
  lcd.print("Main Menu");
  delay(1000);

  for (int letter = 0; letter <= strlen(messagePadded) - 16; letter++) // From 0 to upto n-16 characters supply to below function
  {
    showLetters(0, letter);
  }
}

void showLetters(int printStart, int startLetter)
{
  lcd.setCursor(printStart, 1);
  for (int letter = startLetter; letter <= startLetter + 15; letter++) // Print only 16 chars in Line #2 starting 'startLetter'
  {
    lcd.print(messagePadded[letter]);
  }
  lcd.print(" ");
  delay(250);
}

// function for reading the LCD puttons -- taken from LCD shield test code written by Mark Bramwell, July 2010
int read_LCD_buttons()
{
  adc_key_in = analogRead(0); // read the value from the sensor
  // my buttons when read are centered at these valies: 0, 144, 329, 504, 741
  // we add approx 50 to those values and check to see if we are close
  if (adc_key_in > 1000)
    return btnNONE; // We make this the 1st option for speed reasons since it will be the most likely result
  // For V1.1 us this threshold
  if (adc_key_in < 50)
    return btnRIGHT;
  if (adc_key_in < 250)
    return btnUP;
  if (adc_key_in < 450)
    return btnDOWN;
  if (adc_key_in < 650)
    return btnLEFT;
  if (adc_key_in < 850)
    return btnSELECT;

  return btnNONE; // when all others fail, return this...
}

void loop()
{

  // Read user inputs from the keyboard
  lcd_key = read_LCD_buttons(); // read the buttons

  unsigned long currentMillis = millis(); // Test Short and long press

  // Check which button is pressed and change the menu state accordingly
  switch (lcd_key) // Select button
  {
  case btnSELECT:
  {

    if (menu == 0)
    { // Main menu -> Start test
      menu = 1;
      lcd.begin(16, 2);
      lcd.print("Starting test...");
      delay(1000); // Wait for a second
      lcd.clear();
      lcd.print("Test in progress");
    }

    else if (menu == 1)
    { // Start test -> Stop test
      menu = 2;
      lcd.clear();
      lcd.print("Stopping test...");
      delay(1000); // Wait for a second
      lcd.clear();
      lcd.print("Test stopped");
    }

    else if (menu == 2)
    { // Stop test -> Main menu
      menu = 0;
      lcd.clear();
      lcd.print("Main Menu");
      for (int letter = 0; letter <= strlen(messagePadded) - 16; letter++) // From 0 to upto n-16 characters supply to below function
      {
        showLetters(0, letter);
      }
    }

    else if (menu == 3)
    { // Configure test -> Main menu
      menu = 0;
      lcd.clear();
      lcd.print("Main Menu");
      for (int letter = 0; letter <= strlen(messagePadded) - 16; letter++) // From 0 to upto n-16 characters supply to below function
      {
        showLetters(0, letter);
      }
    }
    break;
  }

  case btnLEFT:
  { // Left button

    if (menu == 0)
    { // Main menu -> Configure test
      menu = 3;
      lcd.clear();
      lcd.print("Configure test");

      // Print use of arrow keys
      lcd.setCursor(0, 1);
      lcd.write(byte(0)); // print up arrow
      lcd.print(":+1000  ");

      // lcd.setCursor(1,1); // set cursor to second column of first row
      lcd.write(byte(1)); // print down arrow
      lcd.print(":-1000");
      delay(500);
      lcd.clear();
      lcd.write(byte(0)); // print up arrow
      lcd.print(":+1000  ");

      // lcd.setCursor(1,1); // set cursor to second column of first row
      lcd.write(byte(1)); // print down arrow
      lcd.print(":-1000");
    }
    break;
  }

  case btnUP:
  { // Up button

    if (menu == 3)
    { // Configure test -> Increase max actuations by one

      if ((currentMillis - LastAction) > FastDelay)
      {
        maxActuations = maxActuations + FastStep;
        lcd.setCursor(0, 1); // Move to the second row
        lcd.print("Max: ");
        lcd.print(maxActuations);
        // delay(150);
        LastAction = currentMillis;
      }

      if ((currentMillis - LastAction) > SlowDelay)
      {
        maxActuations++;
        lcd.setCursor(0, 1); // Move to the second row
        lcd.print("Max: ");
        lcd.print(maxActuations);
        // delay(150);
        LastAction = currentMillis;
      }
    }
    break;
  }

  case btnDOWN:
  { // Down button

    if (menu == 3)
    { // Configure test -> Decrease max actuations by one
      if ((currentMillis - LastAction) > FastDelay)
      {
        maxActuations = maxActuations - FastStep;
        lcd.setCursor(0, 1); // Move to the second row
        lcd.print("Max: ");
        lcd.print(maxActuations);
        // delay(150);
        LastAction = currentMillis;
      }

      if ((currentMillis - LastAction) > SlowDelay)
      {
        maxActuations--;
        lcd.setCursor(0, 1); // Move to the second row
        lcd.print("Max: ");
        lcd.print(maxActuations);
        // delay(150);
        LastAction = currentMillis;
      }

      if (maxActuations < 1)
        maxActuations = 1; // Prevent negative values
      lcd.setCursor(0, 1); // Move to the second row
      lcd.print("                ");
      lcd.setCursor(0, 1);
      lcd.print("Max: ");
      lcd.print(maxActuations);
      delay(150);
    }
    break;
  }

  case btnRIGHT:
  { // Right button

    if (menu == 3)
    { // Configure test -> Reset max actuations to default value
      maxActuations = 10;
      lcd.setCursor(0, 1); // Move to the second row
      lcd.print("                ");
      lcd.setCursor(0, 1);
      lcd.print("Max: ");
      lcd.print(maxActuations);
    }
    break;
  }
  case btnNONE:
  {
    // if no button was pressed, do nothing
    break;
  }
  }

  // Check if the test is in progress
  if (menu == 1)
  {

    // Check if the current actuations are less than the max actuations
    if (currentActuations < maxActuations)
    {

      // Toggle the relay state
      relayOn = !relayOn;

      // Set the relay pin accordingly
      digitalWrite(RELAY, relayOn ? HIGH : LOW);

      // Increment the current actuations if the relay is on
      if (relayOn)
        currentActuations++;

      // Display the current and max actuations on the LCD
      lcd.setCursor(0, 1); // Move to the second row
      lcd.print("Cur: ");
      lcd.print(currentActuations);
      lcd.print(" Max: ");
      lcd.print(maxActuations);

      // Wait for half a second
      delay(500);
    }

    else
    { // Test is done

      // Turn off the relay
      digitalWrite(RELAY, LOW);

      // Display the test result on the LCD
      lcd.clear();
      lcd.print("Test completed");
      lcd.setCursor(0, 1); // Move to the second row
      lcd.print("Press SELECT");

      // Reset the current actuations
      currentActuations = 0;

      menu = 2;
    }
  }
}