// ESP32-S3 N16R8 + ILI9341 + XPT2046-compatible touch.
// Libraries: Adafruit ILI9341, Adafruit GFX Library, XPT2046_Touchscreen.
// LCD: SCK=12 MOSI=11 CS=10 DC=9 RESET=8. LCD SDO disconnected.
// Touch: T_CLK=12 T_DIN=11 T_DO=13 T_CS=7 T_IRQ=6 (polled).
// SD disconnected. Keep the existing working power/backlight connections.
// No startup calibration. Adjust touch mapping constants below if needed.
#include <SPI.h>
#include <Adafruit_GFX.h>
#include <Adafruit_ILI9341.h>
#include <XPT2046_Touchscreen.h>
#include <math.h>

Adafruit_ILI9341 tft(&SPI, 9, 10, 8);
XPT2046_Touchscreen touch(7);
// Small off-screen canvas avoids visible erase/redraw flashes.
GFXcanvas16 eyes(280, 112);
// Approximate raw range after touch.setRotation(1), not calibrated pixels.
constexpr int TOUCH_MIN_X = 200, TOUCH_MAX_X = 3900;
constexpr int TOUCH_MIN_Y = 200, TOUCH_MAX_Y = 3900;
constexpr bool TOUCH_SWAP_XY = false;
constexpr bool TOUCH_FLIP_X = true, TOUCH_FLIP_Y = true;
constexpr uint32_t IDLE_AFTER_MS = 15000;
uint32_t idleBlinkAt = 0, idleLookAt = 0;
bool idle = false, idleLookingAway = false;
float gazeX = 0, gazeY = 0, targetX = 0, targetY = 0;
uint32_t lastTouch = 0, blinkStart = 0, lastFrame = 0, lastDown = 0;
bool looking = false, blinking = false, contact = false;
int previousX = 999, previousY = 999, previousOpen = -1;

void renderEyes(int dx, int dy, int opening) {
  eyes.fillScreen(ILI9341_BLACK);
  for (int i = 0; i < 2; ++i) {
    int x = i == 0 ? 72 : 208;
    eyes.fillRoundRect(x-49, 12, 98, 88, 30, ILI9341_WHITE);
    eyes.fillCircle(x+dx, 56+dy, 25, ILI9341_CYAN);
    eyes.fillCircle(x+dx, 56+dy, 14, ILI9341_BLACK);
    eyes.fillCircle(x+dx-7, 49+dy, 5, ILI9341_WHITE);
    int cover = (100-opening)*44/100;
    if (cover > 0) {
      eyes.fillRect(x-50, 12, 100, cover, ILI9341_BLACK);
      eyes.fillRect(x-50, 100-cover, 100, cover, ILI9341_BLACK);
    }
    if (opening < 7) eyes.fillRoundRect(x-39, 54, 78, 4, 2, ILI9341_CYAN);
  }
  tft.drawRGBBitmap(20, 54, eyes.getBuffer(), 280, 112);
}

void setup() {
  Serial.begin(115200);
  pinMode(10, OUTPUT); digitalWrite(10, HIGH);
  pinMode(7, OUTPUT); digitalWrite(7, HIGH);
  pinMode(6, INPUT_PULLUP);
  SPI.begin(12, 13, 11, 10);
  tft.begin(10000000);
  tft.setRotation(1);
  touch.begin(SPI);
  touch.setRotation(1);
  if (!eyes.getBuffer()) {
    tft.fillScreen(ILI9341_RED);
    Serial.println("Eye canvas allocation failed.");
    while (true) delay(1000);
  }
  randomSeed(micros());
  tft.fillScreen(ILI9341_BLACK);
  tft.setTextColor(ILI9341_CYAN);
  tft.setTextSize(2);
  tft.setCursor(46, 207);
  tft.print("Touch to look!");
  lastFrame = lastTouch = millis();
}

void loop() {
  uint32_t now = millis();
  if (touch.touched()) {
    TS_Point p = touch.getPoint();
    float rawX = TOUCH_SWAP_XY ? p.y : p.x;
    float rawY = TOUCH_SWAP_XY ? p.x : p.y;
    float px = constrain((rawX-TOUCH_MIN_X)*319.0f/(TOUCH_MAX_X-TOUCH_MIN_X), 0.0f, 319.0f);
    if (TOUCH_FLIP_X) px = 319.0f-px;
    float py = constrain((rawY-TOUCH_MIN_Y)*239.0f/(TOUCH_MAX_Y-TOUCH_MIN_Y), 0.0f, 239.0f);
    if (TOUCH_FLIP_Y) py = 239.0f-py;
    idle = false;
    idleLookingAway = false;
    if (!contact) { blinking = true; blinkStart = now; }
    contact = true;
    lastDown = lastTouch = now;
    looking = true;
    targetX = (px-159.5f)/159.5f*20.0f;
    targetY = (py-119.5f)/119.5f*14.0f;
  } else if (contact && now-lastDown > 100) {
    contact = false; // Short release debounce prevents repeated blinks.
  }
  if (looking && now-lastTouch >= 3000) {
    looking = false;
    targetX = targetY = 0;
  }
  // "Unattended" currently means no touch, not camera-based presence detection.
  if (!contact && !looking && now-lastTouch >= IDLE_AFTER_MS) {
    if (!idle) {
      idle = true;
      idleLookingAway = false;
      idleBlinkAt = now + random(400, 1600);
      idleLookAt = now + random(900, 2200);
    }
    if (!blinking && int32_t(now-idleBlinkAt) >= 0) {
      blinking = true;
      blinkStart = now;
      idleBlinkAt = now + random(2500, 6500);
    }
    if (int32_t(now-idleLookAt) >= 0) {
      idleLookingAway = !idleLookingAway;
      if (idleLookingAway) {
        targetX = random(0, 2) ? random(9, 21) : -random(9, 21);
        targetY = random(-12, 13);
        idleLookAt = now + random(800, 2000);
      } else {
        targetX = targetY = 0;
        idleLookAt = now + random(1800, 4500);
      }
    }
  }
  if (now-lastFrame < 33) { delay(2); return; }
  float dt = (now-lastFrame)/1000.0f;
  lastFrame = now;
  float blend = 1.0f-expf(-12.0f*dt);
  gazeX += (targetX-gazeX)*blend;
  gazeY += (targetY-gazeY)*blend;
  int opening = 100;
  if (blinking) {
    uint32_t elapsed = now-blinkStart;
    if (elapsed < 100) opening = 100-int(elapsed);
    else if (elapsed < 170) opening = 0;
    else if (elapsed < 330) opening = int((elapsed-170)*100/160);
    else blinking = false;
  }
  int dx = lroundf(gazeX), dy = lroundf(gazeY);
  if (dx != previousX || dy != previousY || opening != previousOpen) {
    renderEyes(dx, dy, opening);
    previousX = dx; previousY = dy; previousOpen = opening;
  }
}