#include <Wire.h>
#include <LiquidCrystal_I2C.h>

#define UP_BUTTON 2
#define DOWN_BUTTON 3
#define ENTER_BUTTON 4
#define BACK_BUTTON 5
#define BUZZER 6
#define RELAY_WATER 7
#define RELAY_DRAIN 8
#define RELAY_WASH 9
#define RELAY_DRYER 10

LiquidCrystal_I2C lcd(0x27, 16, 2);

int menuIndex = 0;
int washCycles = 1;
int washTime = 1;
int waterLevel = 1;
int dryerTime = 1;
bool inProcess = false;

void setup() {
    pinMode(UP_BUTTON, INPUT_PULLUP);
    pinMode(DOWN_BUTTON, INPUT_PULLUP);
    pinMode(ENTER_BUTTON, INPUT_PULLUP);
    pinMode(BACK_BUTTON, INPUT_PULLUP);
    pinMode(BUZZER, OUTPUT);
    pinMode(RELAY_WATER, OUTPUT);
    pinMode(RELAY_DRAIN, OUTPUT);
    pinMode(RELAY_WASH, OUTPUT);
    pinMode(RELAY_DRYER, OUTPUT);
    
    lcd.init();
    lcd.backlight();
    showWelcomeScreen();
}

void loop() {
    if (!inProcess) {
        showMenu();
    }
}

void showWelcomeScreen() {
    lcd.clear();
    lcd.setCursor(0, 0);
    lcd.print("Washing Machine");
    lcd.setCursor(0, 1);
    lcd.print("V1.0 Press Enter");
    waitForButton(ENTER_BUTTON);
    showMenu();
}

void showMenu() {
    menuIndex = 0;
    while (true) {
        lcd.setCursor(0, 0);
        lcd.print(menuIndex == 0 ? "> Wash Timer  " : "  Wash Timer  ");
        lcd.setCursor(0, 1);
        lcd.print(menuIndex == 1 ? "> Dryer      " : "  Dryer      ");
        
        int btn = getButtonPress();
        if (btn == UP_BUTTON && menuIndex > 0) menuIndex--;
        if (btn == DOWN_BUTTON && menuIndex < 1) menuIndex++;
        if (btn == ENTER_BUTTON) {
            if (menuIndex == 0) setupWashTimer();
            else setupDryer();
        }
        if (btn == BACK_BUTTON) return;  // Implementing back button functionality
    }
}

void setupWashTimer() {
    lcd.clear();
    lcd.print("Select Cycles:");
    while (true) {
        lcd.setCursor(0, 1);
        lcd.print("Cycles: ");
        lcd.print(washCycles);
        lcd.print("  ");
        int btn = getButtonPress();
        if (btn == UP_BUTTON && washCycles < 4) washCycles++;
        if (btn == DOWN_BUTTON && washCycles > 1) washCycles--;
        if (btn == ENTER_BUTTON) break;
        if (btn == BACK_BUTTON) return;
    }
    setupWashTime();
}

void setupWashTime() {
    lcd.clear();
    lcd.print("Set Wash Time");
    while (true) {
        lcd.setCursor(0, 1);
        lcd.print("Time: ");
        lcd.print(washTime);
        lcd.print(" min  ");
        int btn = getButtonPress();
        if (btn == UP_BUTTON && washTime < 10) washTime++;
        if (btn == DOWN_BUTTON && washTime > 1) washTime--;
        if (btn == ENTER_BUTTON) break;
        if (btn == BACK_BUTTON) return;
    }
    setupWaterLevel();
}

void setupWaterLevel() {
    lcd.clear();
    lcd.print("Set Water Level");
    while (true) {
        lcd.setCursor(0, 1);
        lcd.print("Level: ");
        lcd.print(waterLevel);
        lcd.print("  ");
        int btn = getButtonPress();
        if (btn == UP_BUTTON && waterLevel < 7) waterLevel++;
        if (btn == DOWN_BUTTON && waterLevel > 1) waterLevel--;
        if (btn == ENTER_BUTTON) break;
        if (btn == BACK_BUTTON) return;
    }
    startWashingProcess();
}

void startWashingProcess() {
    lcd.clear();
    lcd.print("Begin Wash?");
    lcd.setCursor(0, 1);
    lcd.print("Press Enter");
    waitForButton(ENTER_BUTTON);
    
    for (int i = 0; i < washCycles; i++) {
        lcd.clear();
        lcd.print("Filling Water...");
        digitalWrite(RELAY_WATER, HIGH);
        delay(waterLevel * 2000);
        digitalWrite(RELAY_WATER, LOW);
        
        lcd.clear();
        lcd.print("Washing...");
        digitalWrite(RELAY_WASH, HIGH);
        delay(washTime * 60000);
        digitalWrite(RELAY_WASH, LOW);
        
        lcd.clear();
        lcd.print("Draining...");
        digitalWrite(RELAY_DRAIN, HIGH);
        delay(5000);
        digitalWrite(RELAY_DRAIN, LOW);
    }
    digitalWrite(BUZZER, HIGH);
    delay(3000);
    digitalWrite(BUZZER, LOW);
    showMenu();
}

void setupDryer() {
    lcd.clear();
    lcd.print("Set Dryer Time");
    while (true) {
        lcd.setCursor(0, 1);
        lcd.print("Time: ");
        lcd.print(dryerTime);
        lcd.print(" min  ");
        int btn = getButtonPress();
        if (btn == UP_BUTTON && dryerTime < 10) dryerTime++;
        if (btn == DOWN_BUTTON && dryerTime > 1) dryerTime--;
        if (btn == ENTER_BUTTON) break;
        if (btn == BACK_BUTTON) return;
    }
    startDryingProcess();
}

void startDryingProcess() {
    lcd.clear();
    lcd.print("Drying...");
    digitalWrite(RELAY_DRYER, HIGH);
    for (int i = dryerTime; i > 0; i--) {
        lcd.setCursor(0, 1);
        lcd.print(i);
        lcd.print(" min left  ");
        delay(60000);
    }
    digitalWrite(RELAY_DRYER, LOW);
    digitalWrite(BUZZER, HIGH);
    delay(3000);
    digitalWrite(BUZZER, LOW);
    showMenu();
}

int getButtonPress() {
    while (true) {
        if (!digitalRead(UP_BUTTON)) return debounceButton(UP_BUTTON);
        if (!digitalRead(DOWN_BUTTON)) return debounceButton(DOWN_BUTTON);
        if (!digitalRead(ENTER_BUTTON)) return debounceButton(ENTER_BUTTON);
        if (!digitalRead(BACK_BUTTON)) return debounceButton(BACK_BUTTON);
    }
}

int debounceButton(int button) {
    delay(200);
    while (!digitalRead(button));
    return button;
}

void waitForButton(int button) {
    while (digitalRead(button));
    delay(200);
}