#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET    -1
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

int VRx = A0;
int VRy = A1;
int SW = 2;

void update(float x, float y, bool pressed);

void setup() {
  Serial.begin(9600);

  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println("SSD1306 initialization failed");
    while (1);
  }

  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);

  display.drawRoundRect(92, 10, 11, 15, 2, WHITE);   // Up
  display.drawTriangle(88, 10, 106, 10, 97, 1, WHITE);
  display.drawRoundRect(76, 26, 15, 11, 2, WHITE);   // Left
  display.drawTriangle(76, 22, 76, 40, 67, 31, WHITE);
  display.drawRoundRect(92, 38, 11, 15, 2, WHITE);   // Down
  display.drawTriangle(88, 52, 106, 52, 97, 61, WHITE);
  display.drawRoundRect(104, 26, 15, 11, 2, WHITE);   // Right
  display.drawTriangle(118, 22, 118, 40, 127, 31, WHITE);
  display.drawCircle(97, 31, 5, WHITE);  

  display.display();
  delay(2000);

  pinMode(SW, INPUT_PULLUP);
}

void loop() {
  int rawX = analogRead(VRx);
  int rawY = analogRead(VRy);
  bool pressed = (digitalRead(SW) == LOW);

  float x = -(rawX - 512.0) / 512.0;
  float y = (rawY - 512.0) / 512.0;
  x = constrain(x, -1.0, 1.0);
  y = constrain(y, -1.0, 1.0);

  // Redraw UI each frame
  display.clearDisplay();

  display.drawRoundRect(92, 10, 11, 15, 2, WHITE);   // Up
  display.drawTriangle(88, 10, 106, 10, 97, 1, WHITE);
  display.drawRoundRect(76, 26, 15, 11, 2, WHITE);   // Left
  display.drawTriangle(76, 22, 76, 40, 67, 31, WHITE);
  display.drawRoundRect(92, 38, 11, 15, 2, WHITE);   // Down
  display.drawTriangle(88, 52, 106, 52, 97, 61, WHITE);
  display.drawRoundRect(104, 26, 15, 11, 2, WHITE);   // Right
  display.drawTriangle(118, 22, 118, 40, 127, 31, WHITE);
  display.drawCircle(97, 31, 5, WHITE);              // Center

  update(x, y, pressed);

  display.display();
  delay(100);
}

void update(float x, float y, bool pressed){
  if (pressed) {
    // Blink center and show message
    display.fillCircle(64, 31, 5, WHITE);
    display.setCursor(40, 54);
    display.setTextSize(1);
    display.print("Pressed!");
    return;
  }

  if (x == 0 && y == 0) {
    display.fillCircle(97, 31, 5, WHITE);  // Center
  } else if (x > 0) {
    display.fillRoundRect(104, 26, 15, 11, 2, WHITE);
    display.fillTriangle(118, 22, 118, 40, 127, 31, WHITE);  // Right
  } else if (x < 0) {
    display.fillRoundRect(76, 26, 15, 11, 2, WHITE);
    display.fillTriangle(76, 22, 76, 40, 67, 31, WHITE);  // Left
  }
  
  if (y > 0) {
    display.fillRoundRect(92, 10, 11, 15, 2, WHITE);
    display.fillTriangle(88, 10, 106, 10, 97, 1, WHITE);   // Up
  } else if (y < 0) {
    display.fillRoundRect(92, 38, 11, 15, 2, WHITE);
    display.fillTriangle(88, 52, 106, 52, 97, 61, WHITE);  // Down
  }
}