#include <Wire.h>
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 16, 2);

const int upButtonPin = 10;
const int okButtonPin = 11;
const int downButtonPin = 9;
const int cancelButtonPin = 8;
const int AC = 7;

int batteryPercentage = 0;
float chargingPower = 0;
float chargingTime = 0;
float numberchargingTime = 0;
int numberBatteryPercentage = 0;
float numberChargingPower = 0;

int cancelCount = 0;
int okCount = 0;
bool buttonPressed = false;
bool conditionUsed = false;
bool newDigit = false;

bool isLedOn = false;
int delayButtonClick = 200;
int deleteLetters = 2000;
int On_Off_LCD = 2000;

void setup() {
  lcd.init();
  lcd.begin(16, 2);
  lcd.backlight();
  pinMode(upButtonPin, INPUT_PULLUP);
  pinMode(okButtonPin, INPUT_PULLUP);
  pinMode(downButtonPin, INPUT_PULLUP);
  pinMode(cancelButtonPin, INPUT_PULLUP);
  pinMode(AC, OUTPUT);
  digitalWrite(AC, HIGH);
  conditionUsed = true;
  isLedOn = true;
  displayNumber();
}

void loop() {
  if (okCount == 0) {
    if (numberChargingPower == 0 && !buttonPressed) {
      if (digitalRead(cancelButtonPin) == LOW && !buttonPressed) {
        delay(delayButtonClick);
        switch (cancelCount) {
          case 0:
            buttonPressed = false;
            lcd.noBacklight();
            cancelCount = 1;
            break;
          case 1:
            buttonPressed = false;
            lcd.backlight();
            cancelCount = 0;
            break;
          default:
            cancelCount = 0;
            break;
        }
      }
    }

    if (!conditionUsed) {
      if (digitalRead(cancelButtonPin) == LOW && !conditionUsed) {
        delay(delayButtonClick);
        switch (cancelCount) {
          case 0:
            digitalWrite(AC, HIGH);
            cancelCount = 1;
            isLedOn = true;
            break;
          case 1:
            lcd.backlight();
            conditionUsed = true;
            buttonPressed = false;
            cancelCount = 0;
            break;
        }
      }
    }
  }

  handleOkPress();
  handleNumberControl();

  if (okCount == 6) {
    //displayNumber();
    handleNumberControl();
    chargingPower = numberChargingPower;
    batteryPercentage = numberBatteryPercentage;
    calculateChargingTime();
    countDownTimer();
  }
}

void handleOkPress() {
  if (digitalRead(okButtonPin) == LOW) {
    delay(delayButtonClick);
    okCount++;

    if (!isLedOn) {
      conditionUsed = true;
      if (digitalRead(AC) == LOW) {
        digitalWrite(AC, HIGH);
        isLedOn = true;
      }
    }

    switch (okCount) {
      case 1:
        newDigit = true;
        if (numberChargingPower == 0) {
          numberChargingPower = 0;
        } else {
          numberChargingPower *= 10;
        }
        lcd.backlight();
        displayNumber();
        break;
      case 2:
        newDigit = true;
        if (numberChargingPower == 0) {
          numberChargingPower = 0;
        } else {
          numberChargingPower *= 10;
        }
        displayNumber();
        break;
      case 3:
        if (numberChargingPower > 120.0) {
          numberChargingPower = 120.0;
        }
        numberChargingPower = (float)numberChargingPower;
        displayNumber();
        break;
      case 4:
        newDigit = false;
        numberBatteryPercentage = 0;
        displayNumber();
        break;
      case 5:
        newDigit = true;
        numberBatteryPercentage *= 10;
        displayNumber();
        break;
    }
  }
}

void handleNumberControl() {
  static unsigned long lastDebounceTime = 0;
  const unsigned long debounceDelay = delayButtonClick;

  // If charging power is greater than 0, show the display and set cancelCount to 1
  if (numberChargingPower > 0) {
    lcd.backlight();
    cancelCount = 1;
  }

  if (okCount < 4) {
    // Handle the up button press
    if (digitalRead(upButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();

      if (!isLedOn) {
        buttonPressed = false;
        buttonPressed = 0;
        conditionUsed = true;

        if (digitalRead(AC) == LOW) {
          digitalWrite(AC, HIGH);
          isLedOn = true;
        }
      }

      if (okCount == 3) {
        float decimalPart = numberChargingPower - (int)numberChargingPower;
        if (decimalPart < 0.9) {
          numberChargingPower += 0.1;
        } else {
          numberChargingPower -= 0.9;
        }
      } else {
        if (newDigit) {
          if ((int)numberChargingPower % 10 < 9) {
            numberChargingPower++;
          } else {
            numberChargingPower -= 9;
          }
        } else {
          if ((int)numberChargingPower < 9) {
            numberChargingPower++;
          } else {
            numberChargingPower = 0;
          }
        }
      }

      if (numberChargingPower > 120.0) numberChargingPower = 120.0;
      displayNumber();
    }

    // Handle the down button press
    if (digitalRead(downButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();

      if (!isLedOn) {
        buttonPressed = false;
        buttonPressed = 0;
        conditionUsed = true;

        if (digitalRead(AC) == LOW) {
          digitalWrite(AC, HIGH);
          isLedOn = true;
        } else {
          isLedOn = true;
        }
      }

      if (okCount == 3) {
        float decimalPart = numberChargingPower - (int)numberChargingPower;
        if (decimalPart > 0.0) {
          numberChargingPower -= 0.1;
        } else {
          numberChargingPower += 0.9;
        }
      } else {
        if (newDigit) {
          if ((int)numberChargingPower % 10 > 0) {
            numberChargingPower--;
          } else {
            numberChargingPower += 9;
          }
        } else {
          if ((int)numberChargingPower > 0) {
            numberChargingPower--;
          } else {
            numberChargingPower = 9;
          }
        }
      }

      if (numberChargingPower > 120.0) numberChargingPower = 120.0;
      displayNumber();
    }

    // Handle the cancel button press
    if (digitalRead(cancelButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();
      if (okCount > 0) {
        if (okCount == 3) {
          numberChargingPower = (int)numberChargingPower;
          okCount--;
        } else {
          numberChargingPower = (int)(numberChargingPower / 10);
          okCount--;
        }
      } else {
        numberChargingPower = 0.0;
        okCount = 0;
      }
      newDigit = false;
      displayNumber();
    }
  }

  // Handle control when okCount is greater than 3
  if (okCount > 3) {
    // Handle the up button press for battery percentage
    if (digitalRead(upButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();

      if (newDigit) {
        if (numberBatteryPercentage % 10 < 9) {
          numberBatteryPercentage++;
        } else {
          numberBatteryPercentage -= 9;
        }
      } else {
        if (numberBatteryPercentage < 9) {
          numberBatteryPercentage++;
        } else {
          numberBatteryPercentage = 0;
        }
      }

      displayNumber();
    }

    // Handle the down button press for battery percentage
    if (digitalRead(downButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();

      if (newDigit) {
        if (numberBatteryPercentage % 10 > 0) {
          numberBatteryPercentage--;
        } else {
          numberBatteryPercentage += 9;
        }
      } else {
        if (numberBatteryPercentage > 0) {
          numberBatteryPercentage--;
        } else {
          numberBatteryPercentage = 9;
        }
      }

      displayNumber();
    }

    // Handle the cancel button press for battery percentage
    if (digitalRead(cancelButtonPin) == LOW && millis() - lastDebounceTime > debounceDelay) {
      lastDebounceTime = millis();
      if (okCount > 0) {
        if (okCount == 3) {
          numberBatteryPercentage = numberBatteryPercentage;
          okCount--;
        } else {
          numberBatteryPercentage = numberBatteryPercentage / 10;
          okCount--;
        }
      } else {
        numberBatteryPercentage = 0;
        okCount = 0;
      }
      newDigit = false;
      displayNumber();
    }
  }
}

void displayNumber() {
  if (okCount < 4) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Power: ");
    lcd.setCursor(0, 1);
    lcd.print("        ");
    lcd.setCursor(0, 1);
    char buffer[8];  // ใช้เก็บค่าที่จัดรูปแบบ

    if (okCount == 1) {
      // แสดงตัวเลข 2 หลัก เช่น "01", "05"
      sprintf(buffer, "%02d", (int)numberChargingPower);
    } else if (okCount == 2) {
      // แสดงตัวเลข 3 หลัก เช่น "001", "105"
      sprintf(buffer, "%03d", (int)numberChargingPower);
    } else if (okCount == 3) {
      // แสดงตัวเลขแบบ 3 หลัก + ทศนิยม เช่น "001.0"
      sprintf(buffer, "%03d.%01d", (int)numberChargingPower, (int)((numberChargingPower - (int)numberChargingPower) * 10));
    } else {
      // แสดงตัวเลขปกติ (ไม่มีศูนย์นำหน้า)
      sprintf(buffer, "%d", (int)numberChargingPower);
    }

    lcd.print(buffer);  // แสดงผลตามรูปแบบที่กำหนด
    lcd.print("W");     // เพิ่ม "W" เพื่อแสดง Watt หลังตัวเลข
  }
  if (okCount > 3) {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Battery: ");
    lcd.setCursor(9, 0);
    lcd.print("        ");
    lcd.setCursor(9, 0);
    if (numberBatteryPercentage < 10 && newDigit) {
      lcd.print("0");
    }
    lcd.print(numberBatteryPercentage);
    lcd.print("%");  // เพิ่มเครื่องหมาย % หลังตัวเลข
  }
}
void calculateChargingTime() {
  if (chargingPower > 120.0) chargingPower = 120.0;
  float remainingPercentage = 100 - batteryPercentage;
  float energyToCharge = 19.0 * remainingPercentage / 100.0;
  numberchargingTime = energyToCharge / chargingPower;
  lcd.clear();
  lcd.setCursor(0, 0);
  lcd.print("Charging time:");
  digitalWrite(AC, HIGH);
  if (numberchargingTime>= 1) {
    int hours = (int)numberchargingTime;
    int minutes = (int)((numberchargingTime - hours) * 60);
    int seconds = (int)((numberchargingTime - hours) * 3600 - minutes * 60);
    lcd.setCursor(0, 1);
    lcd.print(hours);
    lcd.print("Hr ");
    lcd.print(minutes);
    lcd.print("min ");
    lcd.print(seconds);
    lcd.print("sec");
  } else if (numberchargingTime < 1 && numberchargingTime >= (1.0 / 60)) {
    int minutes = (int)(numberchargingTime * 60);
    int seconds = (int)((numberchargingTime * 3600) - minutes * 60);
    lcd.setCursor(0, 1);
    lcd.print(minutes);
    lcd.print("min ");
    lcd.print(seconds);
    lcd.print("sec");
  } else {
    int seconds = (int)(numberchargingTime * 3600);
    lcd.setCursor(0, 1);
    lcd.print(seconds);
    lcd.print("sec");
  }
  delay(3000);
  chargingTime = numberchargingTime;
  lcd.clear();
}
void countDownTimer() {
  lcd.setCursor(0, 0);
  lcd.print("Finished in:");
  lcd.noBacklight();
  unsigned long startTime = millis();
  int buttonStateOK = 0;
  unsigned long lastOkPressTime = 0;
  while (true) {
    long remainingTime = (chargingTime * 3600000) - (millis() - startTime);
    if (digitalRead(okButtonPin) == LOW) {
      buttonStateOK = 1;
    } else {
      buttonStateOK = 0;
    }
    if (digitalRead(cancelButtonPin) == LOW) {
      lcd.clear();
      lcd.backlight();
      lcd.print("Cancelled!");
      digitalWrite(AC, HIGH);
      numberChargingPower = 0;
      numberBatteryPercentage = 0;
      okCount = 0;
      chargingPower = 0;
      chargingTime = 0;
      cancelCount = 0;

      delay(1000);
      lcd.clear();

      buttonPressed = false;
      conditionUsed = true;
      newDigit = false;
      displayNumber();
      return;
    }
    switch (buttonStateOK) {
      case 1:
        if (millis() - lastOkPressTime) {
          lastOkPressTime = millis();
          lcd.backlight();
        }
        break;
      default:
        if (millis() - lastOkPressTime >= On_Off_LCD) {
          lcd.noBacklight();
        }
        break;
    }
    switch (remainingTime <= 0) {
      case true:
        lcd.clear();
        lcd.print("Finished!");
        digitalWrite(AC, LOW);
        numberChargingPower = 0;
        numberBatteryPercentage = 0;
        okCount = 0;
        chargingPower = 0;
        chargingTime = 0;
        cancelCount = 0;

        delay(deleteLetters);
        lcd.noBacklight();
        isLedOn = false;
        newDigit = false;
        buttonPressed = true;
        conditionUsed = false;
        displayNumber();
        return;
      case false:
        break;
    }
    int hours = remainingTime / 3600000;
    int minutes = (remainingTime % 3600000) / 60000;
    int seconds = ((remainingTime % 3600000) % 60000) / 1000;
    lcd.setCursor(0, 1);
    char buffer[9];
    sprintf(buffer, "%02d:%02d:%02d", hours, minutes, seconds);
    lcd.print(buffer);
  }
}