#include <Arduino.h>
#include <Wire.h>
#include <Adafruit_SSD1306.h>
#include <EEPROM.h>

#define OLED_SDA 5  // Change to your desired SDA pin
#define OLED_SCL 4  // Change to your desired SCL pin

// GPIO pins for buttons
#define OK_BUTTON_PIN 13    		// DEFAULT IT'S HIGH  SET to LOW
#define UP_BUTTON_PIN 14   		// DEFAULT IT'S HIGH  SET to LOW
#define DOWN_BUTTON_PIN 12  	// DEFAULT IT'S HIGH  SET to LOW

// SH110X OLED Display
#define OLED_RESET -1
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define SSD1306_I2C_ADDRESS 0x3C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

const int MAX_MENU_SETUP_ITEMS = 2;

int selectedDigit = 0;
bool shouldBlink = true;
int pinDigits[4] = {0, 0, 0, 0};
bool settingPIN = false;
bool changingPIN = false;
int enteredPIN[4] = {0, 0, 0, 0};
int savedPIN[4] = {1, 2, 3, 4}; // Default PIN
bool upButtonPressed = false;
bool okButtonPressed = false;
bool downButtonPressed = false;
int lastSetupMenuInteraction = 0;

// Define the possible menu states
enum MenuState {
    MainMenu,
    SetupMenu
};

MenuState currentMenuState = MainMenu;
int selectedMenuItem = 0;

enum SetupMenuState {
    SystemMenu,
    BackToMain
};

SetupMenuState currentSetupMenuState = SystemMenu;
int selectedSetupMenuItem = 0;

// Function prototypes
void splachScreen();
void displaySetupMenu();
void handleSetupMenu();
void handleMenuStats();
void handleOKButton();
void handleSetPIN();
void displaySetPIN();
void handleChangePIN();
void displayChangePIN();

void setup() {
    Serial.begin(115200); // Initialize Serial
    Wire.begin(OLED_SDA, OLED_SCL); // Initialize I2C with custom pins
    EEPROM.begin(4096);  // Specify the size of EEPROM (4096 bytes for 4kb AT24C328)

    // Initialize SH1106G OLED Display
    if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
        Serial.println(F("Error: SSD1306 OLED Display allocation failed"));
    } else {
      Serial.println(F("OLED display initialized"));
    } 

    splachScreen();
  
    pinMode(UP_BUTTON_PIN, INPUT_PULLUP);
    pinMode(DOWN_BUTTON_PIN, INPUT_PULLUP);
    pinMode(OK_BUTTON_PIN, INPUT_PULLUP);
  

}

void splachScreen() {
    display.clearDisplay();
    display.setTextSize(2);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(17, 25);
    display.print("PAKFONES");
    display.display();
    delay(1000);

    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(40, 25);
    display.print("LOADING");
    display.setCursor(53, 35);

    for (int i = 0; i < 3; i++) {
      delay(600);
      display.print(".");
      display.display();
    }
}


void displayMainMenu() {
    display.clearDisplay();
    display.setTextSize(1);
    display.setTextColor(SSD1306_WHITE);
    display.setCursor(40, 25);
    display.print("MAIN MENU");
    display.display();
}


// Function to handle the Setup Menu
void displaySetupMenu() {
    display.clearDisplay(); // Clear the display
    display.setTextSize(1);
    display.setCursor(7, 3);  // Adjust the vertical position
    display.print("=== SETTING MENU ===");

    // Increase the space between title and menu items
    int verticalSpacing = 3;  // Adjust to your preferred spacing

    // Define the setup menu items
    String setupMenuItems[] = {"SYSTEM SETTINGS", "EXIT"};

    // Calculate the y-coordinate for the selected
    int selectedY = 15 + selectedSetupMenuItem * 10;

    // Number of items that can fit on the screen
    int itemsPerPage = 2;

    // Calculate the first visible item based on the selectedSetupMenuItem
    int firstVisibleItem = selectedSetupMenuItem - itemsPerPage / 2;

    // Ensure the firstVisibleItem is within bounds
    if (firstVisibleItem + itemsPerPage > MAX_MENU_SETUP_ITEMS) {
        firstVisibleItem = MAX_MENU_SETUP_ITEMS - itemsPerPage;
    }
    if (firstVisibleItem < 0) {
        firstVisibleItem = 0;
    }

    // Calculate the last visible item
    int lastVisibleItem = firstVisibleItem + itemsPerPage - 1;

    // Draw the scrolling ">" shape before the selected item
    for (int i = 0; i < itemsPerPage; i++) {
        display.setCursor(0, 15 + i * 10 + verticalSpacing); // Add the verticalSpacing
        if (i + firstVisibleItem == selectedSetupMenuItem) {
            display.print(">");
        } else {
            display.print(" ");
        }
    }

    // Draw the menu item names with extra space
    for (int i = 0; i < itemsPerPage; i++) {
        int itemIndex = i + firstVisibleItem;
        display.setCursor(10, 15 + i * 10 + verticalSpacing); // Add the verticalSpacing
        display.print(setupMenuItems[itemIndex]);
    }

    display.display(); // Update the display
    //delay(50);
}

// Function to handle Setup menu menu
void handleSetupMenu() {

    // Wait for ok button to be realesed
    while (digitalRead(OK_BUTTON_PIN) == LOW) {delay(50);}
    // Display the Control Center menu
    displaySetupMenu();

    // Serial.println("Entering handleSetupMenuMenu() loop");

    // Determine the action based on the selected Control Center menu item
    while (true) {
        // Adjust menu selection using UP button
        if (digitalRead(UP_BUTTON_PIN) == LOW) {
            upButtonPressed = true;
            ////beep(); // Beep on button press
        }

        if (upButtonPressed) {
            // Serial.println("Up button pressed");
            selectedSetupMenuItem = (selectedSetupMenuItem - 1 + MAX_MENU_SETUP_ITEMS) % MAX_MENU_SETUP_ITEMS;
            upButtonPressed = false;
            displaySetupMenu();
            delay(149);  // Adjust the delay to slow down the scrolling
        }

        // Adjust menu selection using DOWN button
        if (digitalRead(DOWN_BUTTON_PIN) == LOW) {
            downButtonPressed = true;
            //beep(); // Beep on button press
        }

        if (downButtonPressed) {
            // Serial.println("Down button pressed");
            selectedSetupMenuItem = (selectedSetupMenuItem + 1) % MAX_MENU_SETUP_ITEMS;
            downButtonPressed = false;
            displaySetupMenu();
            delay(149);  // Adjust the delay to slow down the scrolling
        }

        // Check if the OK button is pressed
        bool okButtonPressed = (digitalRead(OK_BUTTON_PIN) == LOW);

        if (okButtonPressed) {
            //beep(); // Beep on button press
            // Determine the action based on the selected Setup menu item
            switch (selectedSetupMenuItem) {
                case SystemMenu:  // Implement actions for OK button in AutoFill state
                currentSetupMenuState = SystemMenu;
                Serial.println("System menu activated");
                return;  // Exit the loop after processing the OK button

            case BackToMain:// Implement actions for OK button in BackToMain state
                    currentMenuState = MainMenu;
                    Serial.println("BackToMain clicked - Returning to Main Menu");
                return;  // Exit the loop after processing the OK button
            }

            delay(149);  // Avoid continuous button presses
            
        }

       // delay(50);  // Adjust the delay based on your button behavior
        
    }
}

// Function to handle OK button
void handleOKButton() {
    //// Serial.println("Handling OK Button");
    int okButtonState = digitalRead(OK_BUTTON_PIN);

   // // Serial.print("OK Button State: ");
   // // Serial.println(okButtonState);

    if (okButtonState == LOW && !okButtonPressed) {
        // Serial.println("OK Button Pressed");
        unsigned long buttonPressStartTime = millis();
        bool setupMenuActivated = false;
        bool beeped = false;  // Flag to track whether the beep has been played

        while (digitalRead(OK_BUTTON_PIN) == LOW && millis() - buttonPressStartTime < 1000) {
            // Beep only once during the button press
            if (!beeped) {
                //beep();  // Beep on the initial button press
                beeped = true;  // Set the flag to true after beeping
            }
            // Continue holding the button
        }

        if (millis() - buttonPressStartTime >= 1000) {
            // Serial.println("Setup Menu Activated");
            setupMenuActivated = true;
        }

        if (setupMenuActivated) {
            // Serial.println("Entering Setup Menu");
            currentMenuState = SetupMenu;
            selectedSetupMenuItem = 0;
            lastSetupMenuInteraction = millis();
            displaySetupMenu();
            
            // Wait for the OK button to be released to avoid accidental clicks
            while (digitalRead(OK_BUTTON_PIN) == LOW) {
                delay(50);
            }

            // Reset the flag when the button is released
            okButtonPressed = false;

            // Add a delay to ensure the Setup Menu stays on the screen
            //delay(50);
        }
    }
}

void handleMenuStats() {
    switch (currentMenuState) {
        case MainMenu:
            displayMainMenu();
            break;

        case SetupMenu:
            displaySetupMenu();
            handleSetupMenu();
            break;

        default:
            Serial.println("Unhandled menu state.");
            break;
    }
}

void handleSetPIN() {

}

void displaySetPIN() {

}

void handleChangePIN() {

}

void displayChangePIN() {

}

void loop() {
  handleMenuStats(); // Handle Menu States
  handleOKButton();

}