#include <Servo.h>
#include <LiquidCrystal_I2C.h>
#include <EEPROM.h>

LiquidCrystal_I2C lcd(0x27, 16, 2);
Servo servos[4]; //servo identities

byte barLine[8] = {0b00000, 0b00000, 0b11111, 0b11111, 0b11111, 0b11111, 0b00000, 0b00000};

#define button1 2 //----------------
#define button2 3 //|    BUTTON    |
#define button3 4 //|  PIN NUMBERS |
#define button4 5 //----------------
#define coinSlot 6 // coin slot counter wire to pin 6
#define LED 7 // LED Anode to pin 7 for processing indicator
#define vending 8 // vendin button to pin 8
#define changeBTN 9
#define acceptBTN 10
#define settingBTN 11
#define relayRes 12
#define sensor1 50
#define sensor2 51
#define sensor3 52
#define sensor4 53

int sensorPins[] = {sensor1, sensor2, sensor3, sensor4};

//Iteam amount variables
int itemvalue1; // Replace 10 with the actual value for item #1
int itemvalue2; // Replace 20 with the actual value for item #2
int itemvalue3; // Replace 30 with the actual value for item #3
int itemvalue4; // Replace 40 with the actual value for item #4

//button selection variables
const int numItems = 4;
int itemValues[numItems] = {itemvalue1, itemvalue2, itemvalue3, itemvalue4};
int buttonPins[numItems] = {button1, button2, button3, button4};
int buttonStatus;

//coin slot variables
int coinBalance;
int pulse;
int coinSlotStatus;
int buttonPressed;
int selectedItem; // Track the selected item
bool coinsInserted = false;

//vending item variables
int vendingStatus;
boolean userBalance = false;

int setDone;
boolean settingsDone = false;
int changeBTNState;

void setup() {
  // put your setup code here, to run once:
  initializing();

  pinMode(sensor1, INPUT_PULLUP);
  pinMode(sensor2, INPUT_PULLUP);
  pinMode(sensor3, INPUT_PULLUP);
  pinMode(sensor4, INPUT_PULLUP);
  pinMode(button1, INPUT_PULLUP);
  pinMode(button2, INPUT_PULLUP);
  pinMode(button3, INPUT_PULLUP);
  pinMode(button4, INPUT_PULLUP);
  pinMode(coinSlot, INPUT_PULLUP);
  pinMode(LED, OUTPUT);
  pinMode(vending, INPUT_PULLUP);
  pinMode(changeBTN, INPUT_PULLUP);
  pinMode(acceptBTN, INPUT_PULLUP);
  pinMode(settingBTN, INPUT_PULLUP);
  pinMode(relayRes, OUTPUT);

  servos[0].attach(30); // Attach servo1 to pin 30
  servos[1].attach(31); // Attach servo2 to pin 31
  servos[2].attach(32); // Attach servo3 to pin 32
  servos[3].attach(33); // Attach servo4 to pin 33

  // Load item values from EEPROM
  for (int i = 0; i < 4; i++) {
    itemValues[i] = EEPROM.read(i); // Read from EEPROM
  }
}

void loop() {
  checkSensorStatus(); // Check sensor status before item selection
  
  //Wait until one of the item buttons is pressed.
  itemSelection();
  //After one of the buttons is pressed, execute the LCD display.

  //INSERT COIN
  insertCoin();
 // INSERT COINS ends here.

  // VENDING the item selected
  vendingItem();
  // Vending done. Select item again.

  settingsMenu();
}

void balanceDisplay(){
  delay(1000);
  char lcdBuffer[16];
  sprintf(lcdBuffer, "  Bal. PHP%d.00", coinBalance);
  lcd.setCursor(0, 0);
  lcd.print(lcdBuffer);
}

void vendingDisplay() {
  lcd.clear();
  LEDindicator();
  delay(500);
  char lcdBuffer[16];
  sprintf(lcdBuffer, "  Bal. PHP%d.00", coinBalance);
  lcd.setCursor(0, 0);
  lcd.print("  ITEM  VENDED");
  lcd.setCursor(0, 1);
  lcd.print(lcdBuffer);
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("   THANK  YOU");
  delay(2000);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("  SELECT  ITEM");
  lcd.setCursor(0, 1);
  lcd.print("PRESS THE BUTTON");
  LEDindicator();
}

void loading(){
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("    LOADING");
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(3, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(4, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(5, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(6, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(7, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(8, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(9, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(10, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(11, barLine);
  lcd.setCursor(11, 1);
  lcd.write(byte(0));
  delay(5);
  lcd.createChar(0, barLine);
  lcd.setCursor(12, 1);
  lcd.write(byte(0));
  delay(5);
  delay(1000);
  digitalWrite(LED, LOW);

}

void initializing(){
  lcd.init();
  lcd.backlight();
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("  INITIALIZNG");
  lcd.setCursor(0, 1);
  lcd.print(" VENDING  MACH.");
  delay(1000);
  loading();
  digitalWrite(LED, HIGH);
  delay(500);
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("  SELECT  ITEM");
  lcd.setCursor(0, 1);
  lcd.print("PRESS THE BUTTON");
}

void itemSelection() {
  for (int i = 0; i < numItems; i++) {
    int buttonStatus = digitalRead(buttonPins[i]);
    int sensorStatus = digitalRead(sensorPins[i]);

    if (buttonStatus == 0 && !coinsInserted && sensorStatus != LOW) {
      // Check if the button is pressed, coins are not inserted, and the sensor is not LOW
      buttonPressed = 1;
      selectedItem = i; // Track the selected item
      LEDindicator();
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("    ITEM #" + String(i + 1, DEC));
      lcd.setCursor(0, 1);
      lcd.print("  IS  SELECTED");
      delay(1000);
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("  INSERT COINS");
      lcd.setCursor(0, 1);
      lcd.print("    PHP ");
      lcd.setCursor(8, 1);
      lcd.print(itemValues[i]);
      balanceDisplay();
    } else if (buttonStatus == 0 && sensorStatus == LOW) {
      // If the sensor is LOW, indicate that the item is unavailable
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("ITEM UNAVAILABLE");
      lcd.setCursor(0, 1);
      lcd.print(" SELECT  OTHERS");
      delay(2000);
      lcd.clear();
      initializing(); // You can call the initializing function to return to the initial state
    }
  }
}

void LEDindicator(){
      digitalWrite(LED, LOW);
      delay(200);
      digitalWrite(LED, HIGH);
      delay(200);
      digitalWrite(LED, LOW);
      delay(200);
      digitalWrite(LED, HIGH);
}

void insertCoin(){
    if (buttonPressed == 1) { // If no button is pressed, coinslot is disabled.
    coinSlotStatus = digitalRead(coinSlot); // wait to insert coins.
    delay(30);
    if (coinSlotStatus == LOW) {
      digitalWrite(LED, LOW);
      userBalance = true;
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print(" COINS INSERTED");
      pulse += 1;
      char lcdBuffer[16];
      sprintf(lcdBuffer, " Bal. PHP %d.00", pulse);
      lcd.setCursor(0, 1);
      lcd.print(lcdBuffer);
      delay(30);
      // Set the coinsInserted flag to true
      coinsInserted = true;
    }
  }
}

void vendingItem(){
  vendingStatus = digitalRead(vending);
  if (vendingStatus == 0 && buttonPressed == 1 && pulse >= itemValues[selectedItem]) {
    coinBalance = pulse - itemValues[selectedItem];
    buttonPressed = 0;
    userBalance = false;
    servos[selectedItem].writeMicroseconds(2000); // rotate
    delay(950);
    servos[selectedItem].writeMicroseconds(1500);  // stop
    delay(500);
    vendingDisplay();
    pulse = coinBalance;
    coinsInserted = false;
  }
}

void tone1(){
  
}

void checkSensorStatus() {
  for (int i = 0; i < numItems; i++) {
    int buttonStatus = digitalRead(buttonPins[i]);
    int sensorStatus = digitalRead(sensorPins[i]);

    if (buttonStatus == 0 && sensorStatus == LOW) {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("ITEM UNAVAILABLE");
      lcd.setCursor(0, 1);
      lcd.print(" SELECT  OTHERS");
      delay(2000);
      lcd.clear();
      initializing(); // You can call the initializing function to return to the initial state
    }
  }
}

void settingsMenu(){
  // Wait to press settingBTN
  if (digitalRead(settingBTN) == LOW) {
    setDone = 1;
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print(" SETTINGS  MENU");
    lcd.setCursor(0, 1);
    lcd.print("CHANGE THE PRICE");
    delay(1000);
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("CHANGE THE PRICE");
    lcd.setCursor(0, 1);
    displayItemValue(selectedItem + 1, itemValues[selectedItem]);
    settingsDone = true;
    delay(1000);
  }

  // After settingBTN is pressed, wait to press changeBTN
  if (settingsDone == true) {
    changeBTNState = digitalRead(changeBTN);
    if (changeBTNState == LOW && setDone == 1) {
      if (itemValues[selectedItem] < 99) {
        itemValues[selectedItem] += 1;
      } else {
        itemValues[selectedItem] = 0; // Reset to 0 if it reaches 99
      }
      displayItemValue(selectedItem + 1, itemValues[selectedItem]);
      delay(150);
    }
  }

  // Press acceptBTN to finish setting an item and move to the next one
  if (digitalRead(acceptBTN) == LOW && settingsDone) {
    selectedItem++;
    if (selectedItem >= 4) {
      // All items are done, exit the settings
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("  ALL SETTINGS");
      lcd.setCursor(0, 1);
      lcd.print("    ARE DONE");
      settingsDone = false;

      // Save item values to EEPROM
      for (int i = 0; i < 4; i++) {
        EEPROM.write(i, itemValues[i]); // Write to EEPROM
      }
      delay(1000);
      digitalWrite(relayRes, HIGH);
    } else {
      lcd.clear();
      lcd.setCursor(0, 0);
      lcd.print("CHANGE THE PRICE");
      lcd.setCursor(0, 1);
      displayItemValue(selectedItem + 1, itemValues[selectedItem]);
      delay(1000);
    }
  }
}

void displayItemValue(int itemNumber, int itemValue) {
  lcd.setCursor(0, 1);
  char lcdBuffer[16];
  sprintf(lcdBuffer, "ITEM %d: P%d.00", itemNumber, itemValue);
  lcd.print(lcdBuffer);
}