ESP32-3248S035C iphone with text

#include <Arduino.h>
#include <SPI.h>
#include <SD.h>
#include <WiFi.h>
#include <nvs_flash.h>
#include <HTTPClient.h>
#include <WiFiClientSecure.h>
#include <time.h>
#include <TFT_eSPI.h>
#include <TAMC_GT911.h>
#include "messinger.h"

// ESP32-3248S035C: display, touch, and card slot are built into this screen.
#define SD_CS_PIN 5
#define SD_SCK_PIN 18
#define SD_MISO_PIN 19
#define SD_MOSI_PIN 23
#define TOUCH_SDA_PIN 33
#define TOUCH_SCL_PIN 32
#define TOUCH_IRQ_PIN 21
#define TOUCH_RESET_PIN 25
#define TFT_BACKLIGHT_PIN 27


enum Page { HOME, SETTINGS, BROWSER, STORE, PHOTOS, PIXEL, FILES, SCREEN_TIME, DEVICE, CHESS, CHECKERS, SUDOKU, GAME_WIFI, MESSENGER, CALC, NOTES, WEATHER, CLOCKAPP, NOTIFICATIONS };

enum GameType { CHESS_GAME, CHECKERS_GAME, SUDOKU_GAME };
enum GameMode { TWO_PLAYER_MODE, AI_OFF_MODE, WIFI_MODE };


// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations

// Forward declarations
void pixelPushUndo();
void pixelPushRedo();

void drawNoteInput();
void drawNoteKeyboard();

uint16_t pixelColor(int i);
void pixelSnapshot(uint16_t *to);
void pixelFlood(int sx,int sy,uint16_t replacement);
void drawPixelCell(int index);
void drawPixelCanvas();
void pixelRestoreCanvas(const uint16_t *snapshot);
void pixelStrokeTo(int px, int py);
void drawPixelPickControl();
void drawPixelEraseControl();
void drawPixelUndoControl();
void drawPixelRedoControl();
void savePixelArt();
void savePixelName(int slot);

void drawBrowserQuery();
void drawBrowserResult();

void addNotification(const String &text);

bool readPhoto(int slot, uint16_t pixels[1024], uint8_t &size);
String jsonValue(const String &s,const String &key);

bool inside(int x,int y);
bool sameChessSide(char a,char b);
bool chessClear(int fx,int fy,int tx,int ty);
bool chessAttacked(int tx,int ty,bool byWhite);
bool chessInCheck(bool white);
bool chessShapeOK(int fx,int fy,int tx,int ty);
bool chessLegal(int fx,int fy,int tx,int ty);
bool chessHasMove(bool white);
void chessStatus();
void checkersStatus();
void playChessMove(int fx,int fy,int tx,int ty,bool transmit);
bool checkerRed(char p);
bool checkerCaptureAt(int fx,int fy);
bool checkersAnyCapture(bool red);
bool checkerMoveOK(int fx,int fy,int tx,int ty);
bool checkerHasMove(bool red);
void playCheckerMove(int fx,int fy,int tx,int ty,bool transmit);
void doAiMove();
void doChessAiMove();
void doCheckersAiMove();

void drawAiPrompt();
void drawAiReply();
String makeAiReply(const String &prompt);
String simpleMathReply(String question);
int spellingDistance(const String &a, const String &b);
String correctSpelling(const String &text);
String urlEncode(const String &text);
String jsonStringValue(const String &json, const String &key);
String lookupFact(const String &prompt);

void label(const String &s, int x, int y, uint16_t fg, uint16_t bg, int size);
void roundButton(int x,int y,int w,int h,const String &s,uint16_t fill,uint16_t fg);
void nav(const String &title);
void card(int x,int y,int color,const String &name,const String &glyph);
void drawSettings();
void drawBrowser();
void drawStore();
void drawPhotos();
void drawFiles();
void drawScreenTime();
void drawDevice();
void drawCalc();
void drawCalcDisplay();
void calculatorKey(const String &key);
void drawNotes();
void drawNotifications();
void refreshNotificationAges();
void drawHomeNotificationBell();
void drawClock();
void drawWeather();
void refreshWeather();
void drawPhotoSlot(int slot, int x, int y, int boxW, int boxH);
void drawPixelStudio();
void drawPixelName();
void refreshClock();
void beginNetworkTime();
String networkTimeText(bool includeSeconds);
void drawHomeClock();
void resetGames();
void chessSquare(int x,int y);
void checkerSquare(int x,int y);
void gameTop(const String&s);
void drawGameWifi();
void sendMove(int fx,int fy,int tx,int ty);
void chessTap(int x,int y);
void countCheckers();
void checkerTap(int x,int y);
void receiveMove();
void tap(int x,int y);

TFT_eSPI tft;
TAMC_GT911 touch(TOUCH_SDA_PIN, TOUCH_SCL_PIN, TOUCH_IRQ_PIN, TOUCH_RESET_PIN, 320, 480);
bool sdCardReady = false;



Page page = HOME;
GameType gameType = CHESS_GAME;
GameMode gameMode = TWO_PLAYER_MODE;
int homeScreen = 0;
bool locked = false;
uint32_t liftedAt = 0;
uint32_t launchedAt = 0;
// Home-screen touches wait until the finger lifts, so a left/right swipe never
// accidentally opens the icon where the swipe began.
bool homeSwipeTracking = false;
int homeSwipeStartX = 0, homeSwipeStartY = 0;

const uint16_t GAME_PORT = 3334;
WiFiServer gameServer(GAME_PORT);
WiFiClient gamePeer;
bool hosting = false, joining = false;
uint32_t retryAt = 0;
uint32_t aiMoveAt = 0;
String savedIp = "192.168.1.96";
char chess[8][8], checkers[8][8];
// Medium-to-hard presets. A new shared round rotates to a different full map.
const uint8_t sudokuPuzzles[3][81] = {
 {5,3,0,0,7,0,0,0,0,6,0,0,1,9,5,0,0,0,0,9,8,0,0,0,0,6,0,8,0,0,0,6,0,0,0,3,4,0,0,8,0,3,0,0,1,7,0,0,0,2,0,0,0,6,0,6,0,0,0,0,2,8,0,0,0,0,4,1,9,0,0,5,0,0,0,0,8,0,0,7,9},
 {0,0,0,2,6,0,7,0,1,6,8,0,0,7,0,0,9,0,1,9,0,0,0,4,5,0,0,8,2,0,1,0,0,0,4,0,0,0,4,6,0,2,9,0,0,0,5,0,0,0,3,0,2,8,0,0,9,3,0,0,0,7,4,0,4,0,0,5,0,0,3,6,7,0,3,0,1,8,0,0,0},
 {0,2,0,6,0,8,0,0,0,5,8,0,0,0,9,7,0,0,0,0,0,0,4,0,0,0,0,3,7,0,0,0,0,5,0,0,6,0,0,0,0,0,0,0,4,0,0,8,0,0,0,0,1,3,0,0,0,0,2,0,0,0,0,0,9,8,0,0,0,3,6,0,0,0,6,0,0,3,0,5,0}
};
const uint8_t sudokuAnswers[3][81] = {
 {5,3,4,6,7,8,9,1,2,6,7,2,1,9,5,3,4,8,1,9,8,3,4,2,5,6,7,8,5,9,7,6,1,4,2,3,4,2,6,8,5,3,7,9,1,7,1,3,9,2,4,8,5,6,9,6,1,5,3,7,2,8,4,2,8,7,4,1,9,6,3,5,3,4,5,2,8,6,1,7,9},
 {4,3,5,2,6,9,7,8,1,6,8,2,5,7,1,4,9,3,1,9,7,8,3,4,5,6,2,8,2,6,1,9,5,3,4,7,3,7,4,6,8,2,9,1,5,9,5,1,7,4,3,6,2,8,5,1,9,3,2,6,8,7,4,2,4,8,9,5,7,1,3,6,7,6,3,4,1,8,2,5,9},
 {1,2,3,6,7,8,9,4,5,5,8,4,2,3,9,7,6,1,9,6,7,1,4,5,3,2,8,3,7,2,4,6,1,5,8,9,6,9,1,5,8,2,4,3,7,4,5,8,7,9,3,6,1,2,8,3,5,9,2,6,1,7,4,2,1,9,8,5,4,3,6,7,7,4,6,3,1,7,2,5,8}
};
uint8_t sudokuPuzzle[81], sudokuAnswer[81], sudokuBoard[81];
int sudokuMap = 0;
int sudokuCell = -1, sudokuMistakes = 0;
bool sudokuStarted = false;
int pickedX = -1, pickedY = -1;
bool whiteTurn = true, redTurn = true, gameDone = false;
String result = "";
String noteText = "My Note";
bool noteCaps = false;
bool noteNumbers = false;
String calc = "0";
float calcStored = 0.0f;
char calcOperation = 0;
bool calcFreshNumber = true;
String aiPrompt = "";
String aiReply = "Ask about this ESP phone, Wi-Fi, games, notes, weather, or time.";
bool aiCaps = false;
bool aiNumbers = false;
int storeNotice = -1;
int selectedPhoto = -1;
String weatherPlace = "";
String weatherNow = "Tap REFRESH to load weather";
String weatherHigh = "--";
String weatherLow = "--";
int weatherCode = -1;
// Pixel Studio edits a 16 by 16 picture and saves it in the existing
// size-byte + RGB565 format used by Photos and Messenger.
// Keep up to seven complete drawing changes. Each undo step has a matching redo step.
uint16_t pixelCanvas[256], pixelUndo[7][256], pixelRedo[7][256];
uint8_t pixelUndoCount = 0, pixelRedoCount = 0;
uint16_t pixelSelected = TFT_RED;
String pixelName = "New picture";
bool pixelErase = false, pixelEye = false, pixelNaming = false, pixelPalette = false;
bool pixelRenameExisting = false;
// Pixel-art names use the same Shift / 123 / SPACE / BACK keyboard as text chat.
bool pixelNameCaps = false, pixelNameNumbers = false;
bool pixelStrokeActive = false;
int pixelLastX = -1, pixelLastY = -1;
int fileGalleryPage = 0;
int fileGallerySelected = -1;
const int PIXEL_ART_SLOTS = 20;
const int MAX_NOTIFICATIONS = 20;
String notificationTexts[MAX_NOTIFICATIONS];
uint32_t notificationReceivedAt[MAX_NOTIFICATIONS];
int notificationCount = 1;
int unreadNotificationCount = 1;
uint32_t lastNotificationDraw = 0;
uint32_t lastClockDraw = 0;
uint32_t lastHomeClockDraw = 0;
uint32_t lastNtpAttempt = 0;
bool networkTimeReady = false;

// Keep a separate alert for every received message or save result.
void addNotification(const String &text) {
  if (notificationCount >= MAX_NOTIFICATIONS) {
    for (int i = 0; i < MAX_NOTIFICATIONS - 1; i++) {
      notificationTexts[i] = notificationTexts[i + 1];
      notificationReceivedAt[i] = notificationReceivedAt[i + 1];
    }
    notificationCount = MAX_NOTIFICATIONS - 1;
  }
  notificationTexts[notificationCount] = text;
  notificationReceivedAt[notificationCount] = millis();
  notificationCount++;
  unreadNotificationCount++;
  // A new alert changes the badge immediately, even while the launcher is open.
  // The alert list itself is redrawn only when its contents changed.
  if (page == HOME) drawHomeNotificationBell();
  else if (page == NOTIFICATIONS) drawNotifications();
}

void drawHome();
void open(Page p);
void drawChess(bool full=true);
void drawCheckers(bool full=true);
void drawSudoku(bool full=true);
void sudokuTap(int x,int y);
void sendSudokuState();

void label(const String &s, int x, int y, uint16_t fg, uint16_t bg, int size=1) { tft.setTextColor(fg,bg); tft.setTextSize(size); tft.setCursor(x,y); tft.print(s); }
void roundButton(int x,int y,int w,int h,const String &s,uint16_t fill,uint16_t fg=TFT_WHITE) { tft.fillRoundRect(x,y,w,h,12,fill); label(s,x+(w-(int)s.length()*6)/2,y+h/2-4,fg,fill); }
void nav(const String &title) {
  // Each app starts on an opaque black page: launcher icons never show underneath it.
  tft.fillScreen(TFT_BLACK);
  tft.fillRect(0,0,320,56,TFT_BLACK);
  tft.drawFastHLine(0,55,320,tft.color565(48,48,52));
  roundButton(8,10,58,33,"HOME",tft.color565(35,35,39));
  label("<",15,18,TFT_WHITE,tft.color565(35,35,39),2);
  label(title,78,18,TFT_WHITE,TFT_BLACK,2);
}
void card(int x,int y,int color,const String &name,const String &glyph) {
  // Phone-style app tile: a clean rounded square, a thin pale edge, and a small
  // lower shadow. This follows the colorful icon-grid look without reusing any
  // company logo artwork.
  tft.fillRoundRect(x+3,y+5,62,62,17,tft.color565(8,27,50));
  tft.fillRoundRect(x-1,y-1,64,64,17,tft.color565(248,251,255));
  tft.fillRoundRect(x,y,62,62,16,color);
  tft.drawRoundRect(x,y,62,62,16,tft.color565(225,246,255));
  // A narrow shine along the top edge makes the tile look layered, not flat.
  tft.drawRoundRect(x+3,y+3,56,56,13,tft.color565(255,255,255));
  if (name == "Chess") {
    // A white king and a black pawn make the Chess icon recognizable at a glance.
    tft.fillRect(x+20,y+17,22,4,TFT_WHITE);
    tft.fillCircle(x+31,y+25,6,TFT_WHITE);
    tft.fillTriangle(x+22,y+42,x+40,y+42,x+35,y+28,TFT_WHITE);
    tft.fillRoundRect(x+18,y+43,26,6,3,TFT_WHITE);
    tft.fillCircle(x+46,y+43,7,TFT_BLACK);
    tft.fillRect(x+38,y+49,16,4,TFT_BLACK);
  } else if (name == "Checkers") {
    // Red and blue counters on a tiny board make the Checkers icon distinct.
    for(int r=0;r<3;r++) for(int c=0;c<3;c++) {
      uint16_t sq=((r+c)&1)?tft.color565(235,235,235):tft.color565(65,65,72);
      tft.fillRect(x+14+c*12,y+22+r*10,12,10,sq);
    }
    tft.fillCircle(x+20,y+28,7,TFT_RED);
    tft.drawCircle(x+20,y+28,5,TFT_YELLOW);
    tft.fillCircle(x+43,y+47,7,TFT_BLUE);
    tft.drawCircle(x+43,y+47,5,TFT_CYAN);
  } else {
    // Each tile has a deliberately different, high-contrast pictogram. The
    // symbol is drawn directly on the colored square, like a modern app grid;
    // no black box or pale oval is placed behind its artwork.
    tft.setTextDatum(MC_DATUM);
    tft.setTextColor(TFT_WHITE,color);
    tft.setTextSize(3);
    if(name=="Messenger" || name=="Chat") { /* layered blue chat bubble */ tft.fillCircle(x+31,y+39,20,tft.color565(20,108,245)); tft.fillRoundRect(x+13,y+26,36,24,10,TFT_WHITE); tft.fillTriangle(x+20,y+46,x+19,y+54,x+28,y+49,TFT_WHITE); tft.fillCircle(x+23,y+38,2,tft.color565(20,108,245)); tft.fillCircle(x+31,y+38,2,tft.color565(20,108,245)); tft.fillCircle(x+39,y+38,2,tft.color565(20,108,245)); }
    else if(name=="AI Chat" || name=="AI") { /* centered black tile with a balanced white geometric AI mark */
      const uint16_t violet=tft.color565(120,78,246), blue=tft.color565(50,190,255), glow=tft.color565(198,172,255);
      // A new luminous assistant orb: centered, colorful, and separate from the old black mark.
      tft.fillCircle(x+31,y+39,22,tft.color565(72,43,170));
      tft.fillCircle(x+31,y+39,18,violet);
      tft.fillCircle(x+31,y+39,13,blue);
      tft.fillCircle(x+27,y+34,6,glow);
      tft.fillCircle(x+27,y+34,3,TFT_WHITE);
      tft.drawLine(x+20,y+48,x+25,y+43,TFT_WHITE);
      tft.drawLine(x+37,y+46,x+42,y+51,TFT_WHITE);
      tft.fillCircle(x+19,y+49,3,TFT_WHITE);
      tft.fillCircle(x+43,y+52,3,TFT_WHITE);
      tft.drawCircle(x+31,y+39,22,TFT_WHITE);
      // Old black-tile outline removed.
      // Old geometric logo strokes removed.
      // Keep all arms inside one centered 36-pixel square so the mark does not
      // lean down or right in either the launcher grid or the bottom dock.
      //
      //
      //
      //
      //
      //
      //
      //
      //
      //
    }
    else if(name=="App Store") { /* three luminous strokes form an app-store A */ tft.fillCircle(x+31,y+39,20,tft.color565(72,92,240)); tft.drawLine(x+20,y+49,x+31,y+24,TFT_WHITE); tft.drawLine(x+31,y+24,x+44,y+49,TFT_WHITE); tft.drawLine(x+24,y+42,x+40,y+42,TFT_WHITE); tft.fillCircle(x+20,y+49,2,TFT_WHITE); tft.fillCircle(x+44,y+49,2,TFT_WHITE); }
    else if(name=="Settings" || name=="Setup") { for(int a=0;a<8;a++){float r=a*0.785f;tft.fillCircle(x+31+(int)(12*cos(r)),y+39+(int)(12*sin(r)),4,TFT_WHITE);} tft.fillCircle(x+31,y+39,12,TFT_WHITE); tft.fillCircle(x+31,y+39,5,color); }
    else if(name=="Calculator") { /* a real mini calculator face, not a character tile */ tft.fillRoundRect(x+15,y+20,32,37,7,TFT_WHITE); tft.fillRoundRect(x+19,y+24,24,8,2,tft.color565(55,66,80)); for(int rr=0;rr<2;rr++)for(int cc=0;cc<3;cc++)tft.fillCircle(x+22+cc*9,y+40+rr*8,3,cc==2?tft.color565(255,146,34):tft.color565(95,105,116)); }
    else if(name=="Notes") { /* cream paper with a folded corner and warm writing lines */ tft.fillRoundRect(x+16,y+19,31,38,5,tft.color565(255,246,190)); tft.fillTriangle(x+38,y+19,x+47,y+19,x+47,y+29,tft.color565(250,207,72)); tft.drawFastHLine(x+21,y+35,20,tft.color565(237,152,40)); tft.drawFastHLine(x+21,y+42,17,tft.color565(237,152,40)); tft.drawFastHLine(x+21,y+49,13,tft.color565(237,152,40)); }
    else if(name=="Drawing") { /* four overlapping color petals make a gallery flower */ tft.fillCircle(x+24,y+34,11,TFT_YELLOW); tft.fillCircle(x+38,y+34,11,TFT_RED); tft.fillCircle(x+24,y+47,11,tft.color565(44,192,111)); tft.fillCircle(x+38,y+47,11,tft.color565(48,151,245)); tft.fillCircle(x+31,y+40,7,TFT_WHITE); }
    else if(name=="Files" || name=="Storage") { /* a dimensional blue folder with a paper tab */ tft.fillRoundRect(x+14,y+27,35,25,5,tft.color565(47,145,242)); tft.fillRoundRect(x+17,y+22,16,11,4,tft.color565(102,190,255)); tft.fillRoundRect(x+17,y+34,29,14,3,tft.color565(114,197,255)); }
    else if(name=="Clock") { /* clean black-and-white analog clock */ tft.fillCircle(x+31,y+39,20,TFT_WHITE); tft.drawCircle(x+31,y+39,18,tft.color565(40,40,45)); for(int a=0;a<12;a++){float r=a*0.5236f;tft.fillCircle(x+31+(int)(14*cos(r)),y+39+(int)(14*sin(r)),1,TFT_BLACK);} tft.drawLine(x+31,y+39,x+31,y+27,TFT_BLACK); tft.drawLine(x+31,y+39,x+41,y+44,TFT_BLACK); tft.fillCircle(x+31,y+39,2,TFT_RED); }
    else if(name=="Weather") { /* glossy sun peeking through a soft cloud */ for(int a=0;a<8;a++){float r=a*0.785f;tft.drawLine(x+23+(int)(14*cos(r)),y+32+(int)(14*sin(r)),x+23+(int)(19*cos(r)),y+32+(int)(19*sin(r)),TFT_YELLOW);} tft.fillCircle(x+23,y+32,12,TFT_YELLOW); tft.fillCircle(x+39,y+43,10,TFT_WHITE); tft.fillCircle(x+30,y+45,12,TFT_WHITE); tft.fillRoundRect(x+23,y+43,28,11,6,TFT_WHITE); }
    else if(name=="Screen Time") { tft.drawCircle(x+31,y+37,16,TFT_WHITE); tft.drawLine(x+31,y+37,x+31,y+25,TFT_WHITE); }
    else if(name=="Device Info") { tft.fillRoundRect(x+20,y+19,22,37,4,TFT_WHITE); tft.setTextColor(color,TFT_WHITE); tft.setTextSize(2); tft.drawString("i",x+31,y+30); }
    else tft.drawString(glyph,x+31,y+34);
  }
  // Draw the app name transparently so no black rectangle sits behind it.
  tft.setTextDatum(MC_DATUM);
  tft.setTextColor(TFT_WHITE);
  tft.setTextSize(1);
  tft.drawString(name,x+31,y+76);
  tft.setTextDatum(TL_DATUM);
}

String networkTimeText(bool includeSeconds) {
  if (!networkTimeReady) return includeSeconds ? "--:--:--" : "--:--";
  struct tm timeInfo;
  if (!getLocalTime(&timeInfo, 10)) { networkTimeReady = false; return includeSeconds ? "--:--:--" : "--:--"; }
  char stamp[10];
  strftime(stamp, sizeof(stamp), includeSeconds ? "%H:%M:%S" : "%H:%M", &timeInfo);
  return String(stamp);
}

void beginNetworkTime() {
  if (WiFi.status() != WL_CONNECTED || networkTimeReady || millis() - lastNtpAttempt < 10000) return;
  lastNtpAttempt = millis();
  // Eastern Time automatically changes between EST and daylight-saving EDT.
  configTzTime("EST5EDT,M3.2.0/2,M11.1.0/2", "pool.ntp.org", "time.nist.gov");
  struct tm timeInfo;
  networkTimeReady = getLocalTime(&timeInfo, 1200);
}

void drawHomeClock() {
  // Redraw only the transparent-looking status strip.  It restores the wallpaper
  // behind the clock rather than putting time or Wi-Fi inside black rectangles.
  for (int y = 0; y < 38; y += 2) {
    uint8_t r = 10 + (y * 2 / 38), g = 105 + (y * 8 / 38), b = 175 - (y * 4 / 38);
    tft.fillRect(0, y, 320, 2, tft.color565(r, g, b));
  }
  tft.setTextColor(TFT_WHITE);
  tft.setTextSize(2);
  tft.setCursor(16, 12);
  tft.print(networkTimeText(false));
  tft.setTextSize(1);
  tft.setCursor(78, 18);
  tft.setTextColor(tft.color565(220, 245, 255));
  tft.print(networkTimeReady ? "ET" : "sync");
  tft.setTextColor(TFT_WHITE);
  tft.setCursor(228, 15);
  tft.print(WiFi.status() == WL_CONNECTED ? "Wi-Fi" : "No Wi-Fi");
  // A small signal mark replaces a heavy status container.
  uint16_t signal = WiFi.status() == WL_CONNECTED ? TFT_WHITE : TFT_LIGHTGREY;
  tft.drawFastVLine(294, 25, 4, signal);
  tft.drawFastVLine(299, 21, 8, signal);
  tft.drawFastVLine(304, 17, 12, signal);
}

void drawHome() {
  page=HOME;
  // A layered blue/teal wallpaper gives the small screen the same clean phone feel.
  // Use 16 broad wallpaper bands rather than 120 tiny strips. This preserves the
  // layered blue wallpaper while greatly reducing display commands on each Home redraw.
  for(int y=0;y<480;y+=16) {
    uint8_t r=10+(y*22/480), g=105+(y*70/480), b=175-(y*35/480);
    tft.fillRect(0,y,320,16,tft.color565(r,g,b));
  }
  tft.fillCircle(292,302,150,tft.color565(37,173,183));
  tft.fillCircle(42,420,130,tft.color565(33,105,205));
  drawHomeClock();
  drawHomeNotificationBell();
  const char* names[16]={"Messenger","AI Chat","App Store","Settings","Chess","Checkers","Sudoku","Calculator","Notes","Drawing","Photos","Clock","Weather","Screen Time","Storage","Device Info"};
  const char* icons[16]={"M","AI","A","G","C","D","9","+","N","P","F","o","~","T","S","i"};
  uint16_t colors[16]={TFT_DARKGREEN,tft.color565(91,70,230),TFT_MAGENTA,TFT_DARKGREY,TFT_BLUE,TFT_ORANGE,tft.color565(30,115,180),TFT_ORANGE,TFT_PURPLE,TFT_CYAN,TFT_DARKGREY,TFT_ORANGE,TFT_CYAN,TFT_PURPLE,TFT_DARKGREY,TFT_BLUE};
  int start=homeScreen*12, count=min(12,16-start);
  for(int i=0;i<count;i++){int x=17+(i%4)*77,y=78+(i/4)*103;card(x,y,colors[start+i],names[start+i],icons[start+i]);}
  // The dock stays in one place like a phone, and the page control switches the remaining apps.
  // A soft glass-like dock separates the always-ready apps from the wallpaper.
  tft.fillRoundRect(10,395,300,74,26,tft.color565(24,83,157));
  tft.drawRoundRect(10,395,300,74,26,tft.color565(170,235,255));
  tft.drawFastHLine(31,399,258,tft.color565(109,194,230));
  // Four 62-pixel icons with equal gaps: this is centered inside the 300-pixel dock.
  card(17,401,TFT_DARKGREEN,"Chat","M");
  card(92,401,tft.color565(91,70,230),"AI","AI");
  card(167,401,TFT_PURPLE,"Notes","N");
  card(242,401,TFT_DARKGREY,"Setup","G");
  tft.fillCircle(151,385,homeScreen?4:6,TFT_WHITE);
  tft.fillCircle(169,385,homeScreen?6:4,TFT_WHITE);
}

// A simple black alert circle makes notifications easy to spot on the Home screen.
void drawHomeNotificationBell() {
  // Restore the small wallpaper area, then draw a black circle with a white !.
  tft.fillCircle(287, 50, 16, tft.color565(19, 126, 171));
  tft.fillCircle(287, 50, 14, TFT_BLACK);
  tft.setTextDatum(MC_DATUM);
  tft.setTextColor(TFT_WHITE, TFT_BLACK);
  tft.setTextSize(2);
  tft.drawString("!", 287, 50);
  tft.setTextDatum(TL_DATUM);
  if (unreadNotificationCount > 0) {
    tft.fillCircle(304, 37, 10, TFT_RED);
    tft.drawCircle(304, 37, 10, tft.color565(255, 177, 180));
    tft.setTextDatum(MC_DATUM); tft.setTextColor(TFT_WHITE, TFT_RED); tft.setTextSize(1);
    tft.drawString(unreadNotificationCount > 9 ? "9+" : String(unreadNotificationCount), 304, 37);
    tft.setTextDatum(TL_DATUM);
  }
}

void drawSettings(){
  nav("Settings");
  tft.fillRoundRect(12,69,296,34,9,tft.color565(30,30,32));
  label("Search",43,80,TFT_LIGHTGREY,tft.color565(30,30,32));
  tft.drawCircle(29,85,6,TFT_LIGHTGREY); tft.drawLine(33,89,38,94,TFT_LIGHTGREY);
  tft.fillRoundRect(12,113,296,65,12,tft.color565(30,30,32));
  tft.fillCircle(45,145,22,tft.color565(245,207,151));
  label("ESP Phone",78,128,TFT_WHITE,tft.color565(30,30,32),2);
  String storageLine = "Insert microSD card";
  if (sdCardReady) {
    float freeGb = (SD.totalBytes() - SD.usedBytes()) / 1073741824.0f;
    storageLine = String(freeGb, 2) + " GB free on microSD";
  }
  label(storageLine,78,151,TFT_LIGHTGREY,tft.color565(30,30,32));
  const char* a[]={"Wi-Fi","Display & brightness","Downloads","Storage","Screen Time","About this ESP Phone"};
  const uint16_t icon[]={TFT_BLUE,TFT_ORANGE,TFT_PURPLE,TFT_GREEN,TFT_MAGENTA,TFT_DARKGREY};
  for(int i=0;i<6;i++){
    int y=190+i*45; uint16_t bg=tft.color565(30,30,32);
    tft.fillRoundRect(12,y,296,40,9,bg); tft.fillRoundRect(21,y+7,26,26,6,icon[i]);
    label(i==0?"~":"",28,y+13,TFT_WHITE,icon[i],2);
    label(a[i],58,y+13,TFT_WHITE,bg); label(">",281,y+12,TFT_LIGHTGREY,bg,2);
  }
}
void drawAiPrompt(){
  tft.fillRoundRect(12,67,296,42,16,TFT_WHITE);
  String shown=aiPrompt.length()?aiPrompt:"Ask the AI helper";
  label(shown.substring(max(0,(int)shown.length()-36)),23,82,aiPrompt.length()?TFT_BLACK:TFT_DARKGREY,TFT_WHITE);
}
String urlEncode(const String &text) {
  const char *hex = "0123456789ABCDEF";
  String encoded;
  for (size_t i = 0; i < text.length(); i++) {
    uint8_t c = (uint8_t)text.charAt(i);
    if ((c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') ||
        (c >= '0' && c <= '9') || c == '-' || c == '_' || c == '.') encoded += (char)c;
    else { encoded += '%'; encoded += hex[c >> 4]; encoded += hex[c & 15]; }
  }
  return encoded;
}

String jsonStringValue(const String &json, const String &key) {
  int p = json.indexOf("\"" + key + "\":\"");
  if (p < 0) return "";
  p += key.length() + 4;
  String value;
  bool escaped = false;
  for (; p < (int)json.length(); p++) {
    char c = json.charAt(p);
    if (escaped) {
      if (c == 'n') value += ' ';
      else if (c == 't') value += ' ';
      else value += c;
      escaped = false;
    } else if (c == '\\') escaped = true;
    else if (c == '\"') break;
    else value += c;
  }
  return value;
}

String lookupFact(const String &prompt) {
  if (WiFi.status() != WL_CONNECTED) return "Connect to Wi-Fi first, then tap ASK for a general answer.";
  WiFiClientSecure secure;
  secure.setInsecure();
  HTTPClient http;
  http.setTimeout(9000);
  String searchUrl = "https://en.wikipedia.org/w/api.php?action=query&list=search&srsearch=" + urlEncode(prompt) + "&format=json&utf8=1";
  if (!http.begin(secure, searchUrl)) return "I could not reach the answer service. Try again.";
  int status = http.GET();
  String search = status == 200 ? http.getString() : "";
  http.end();
  String title = jsonStringValue(search, "title");
  if (!title.length()) return "I could not find a clear answer. Try using a few different words.";
  if (!http.begin(secure, "https://en.wikipedia.org/api/rest_v1/page/summary/" + urlEncode(title))) return "I found a topic but could not open its answer.";
  status = http.GET();
  String summary = status == 200 ? http.getString() : "";
  http.end();
  String answer = jsonStringValue(summary, "extract");
  if (!answer.length()) return "I found " + title + ", but it has no short answer.";
  // Keep the reply card readable; the first sentence is usually the direct answer.
  int end = answer.indexOf('.');
  if (end > 20) answer = answer.substring(0, end + 1);
  if (answer.length() > 150) answer = answer.substring(0, 147) + "...";
  return answer;
}

String simpleMathReply(String question) {
  // This small calculator understands a simple pair of numbers such as
  // "2 * 2", "what is 8 plus 4", or "10 divided by 2" without Wi-Fi.
  question.toLowerCase();
  question.replace("multiplied by", "*");
  question.replace("times", "*");
  question.replace("divided by", "/");
  question.replace("plus", "+");
  question.replace("minus", "-");
  int firstDigit = -1;
  for (int i = 0; i < (int)question.length(); i++) {
    if (isDigit(question.charAt(i)) || question.charAt(i) == '.') { firstDigit = i; break; }
  }
  if (firstDigit < 0) return "";
  String expression = question.substring(firstDigit);
  float left = 0.0f, right = 0.0f;
  char operation = 0;
  if (sscanf(expression.c_str(), "%f %c %f", &left, &operation, &right) != 3) return "";
  // Only accept calculator operators. This prevents ordinary fact questions
  // containing a year or another number from being treated as arithmetic.
  if (operation != '+' && operation != '-' && operation != '*' && operation != 'x' && operation != '/') return "";
  if (operation == 'x') operation = '*';
  if (operation == '/' && right == 0.0f) return "You cannot divide by zero.";
  float answer = left;
  if (operation == '+') answer += right;
  else if (operation == '-') answer -= right;
  else if (operation == '*') answer *= right;
  else answer /= right;
  String shown = String(answer, 4);
  while (shown.indexOf('.') >= 0 && shown.endsWith("0")) shown.remove(shown.length() - 1);
  if (shown.endsWith(".")) shown.remove(shown.length() - 1);
  return String(left, 4) + " " + operation + " " + String(right, 4) + " = " + shown;
}

int spellingDistance(const String &a, const String &b) {
  // Small edit-distance check: one missing, extra, or wrong letter still matches.
  int la=a.length(), lb=b.length();
  if(abs(la-lb)>2) return 3;
  int row[18], next[18];
  for(int j=0;j<=lb;j++) row[j]=j;
  for(int i=1;i<=la;i++) {
    next[0]=i;
    for(int j=1;j<=lb;j++) next[j]=min(min(row[j]+1,next[j-1]+1),row[j-1]+(a.charAt(i-1)==b.charAt(j-1)?0:1));
    for(int j=0;j<=lb;j++) row[j]=next[j];
  }
  return row[lb];
}

String correctSpelling(const String &text) {
  // Correct only familiar app/question words, so names and unusual fact queries stay intact.
  const char* words[]={"hello","what","when","where","weather","wifi","internet","sudoku","chess","checkers","messenger","notes","clock","time","pixel","photos","files","storage","settings","divide","division","america","formed","founded","independence"};
  String fixed="", token="";
  for(int i=0;i<=text.length();i++) {
    char ch=i<text.length()?text.charAt(i):' ';
    if(isAlphaNumeric(ch)) token+=ch;
    else {
      if(token.length()>2) {
        String lower=token; lower.toLowerCase();
        int best=3; const char* match=nullptr;
        for(unsigned int w=0;w<sizeof(words)/sizeof(words[0]);w++) { int d=spellingDistance(lower,words[w]); if(d<best){best=d;match=words[w];} }
        if(match && best<=((lower.length()>6)?2:1)) token=String(match);
      }
      fixed+=token; fixed+=ch; token="";
    }
  }
  fixed.trim();
  return fixed;
}

String makeAiReply(const String &prompt){
  // Correct common phone-keyboard slips before local answers or an online lookup.
  String question=correctSpelling(prompt); question.trim();
  String q=question; q.toLowerCase();
  q.replace("amarica","america");
  q.replace("amerca","america");
  q.replace("forned","formed");
  q.replace("foundeded","founded");
  q.replace("whats ","what is ");
  if(!q.length()) return "Type a question, then tap ASK.";
  if(q=="hi" || q=="hello" || q=="hey" || q.startsWith("hi ") || q.startsWith("hello ")) return "Hi, how are you? What would you like to ask?";
  String mathAnswer = simpleMathReply(q);
  if(mathAnswer.length()) return mathAnswer;
  if(q.indexOf("wifi")>=0 || q.indexOf("wi-fi")>=0 || q.indexOf("internet")>=0) return "Open Messenger to choose Wi-Fi. Saved Wi-Fi is tried first.";
  if(q.indexOf("time")>=0 || q.indexOf("clock")>=0) return "The clock uses Wi-Fi time and shows Eastern Time when connected.";
  if(q.indexOf("weather")>=0) return "Open Weather and tap REFRESH after Wi-Fi connects.";
  if(q.indexOf("note")>=0) return "Notes save to /notes.txt on the microSD card.";
  if(q.indexOf("chess")>=0 || q.indexOf("checker")>=0) return "Choose 2 PLAY, AI, or WI-FI at the top of either game.";
  if(q.indexOf("mess")>=0 || q.indexOf("text")>=0) return "Messenger keeps listening for new texts and adds an alert for each one.";
  if(q.indexOf("america")>=0 && (q.indexOf("formed")>=0 || q.indexOf("founded")>=0 || q.indexOf("independ")>=0 || q.indexOf("born")>=0)) return "The United States declared independence from Great Britain on July 4, 1776.";
  // For general questions, use the corrected words with Wikipedia's live summary service.
  return lookupFact(q);
}
void drawAiReply(){
  // A taller, layered answer card keeps useful answers visible without covering the keyboard.
  uint16_t bg=tft.color565(35,30,62);
  tft.fillRoundRect(12,119,296,132,18,bg);
  tft.fillRoundRect(22,130,34,34,10,tft.color565(100,76,245));
  label("*",33,138,TFT_WHITE,tft.color565(100,76,245),2);
  label("AI CHAT",68,136,TFT_CYAN,bg,2);
  String first=aiReply.substring(0,min(40,(int)aiReply.length()));
  String second=aiReply.length()>40?aiReply.substring(40,min(80,(int)aiReply.length())):"";
  String third=aiReply.length()>80?aiReply.substring(80,min(120,(int)aiReply.length())):"";
  label(first,25,174,TFT_WHITE,bg);
  if(second.length()) label(second,25,194,TFT_WHITE,bg);
  if(third.length()) label(third,25,214,TFT_WHITE,bg);
}
void drawBrowser(){
  nav("AI Chat");
  drawAiPrompt();
  roundButton(252,73,48,29,"ASK",tft.color565(91,70,230));
  drawAiReply();
  // Match Messenger's text keyboard: Shift, 123, letters, SPACE, BACK, and SEND.
  // AI Chat deliberately has no emoji key or emoji page.
  tft.fillRect(0,326,320,154,TFT_LIGHTGREY);
  const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
  const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
  for(int r=0;r<3;r++){const char* line=aiNumbers?digits[r]:letters[r];int n=strlen(line),gap=1,w=(320-(n-1)*gap)/n,x=(320-(n*(w+gap)-gap))/2,y=326+r*37;for(int i=0;i<n;i++){tft.fillRoundRect(x+i*(w+gap),y,w,36,5,TFT_WHITE);tft.drawRoundRect(x+i*(w+gap),y,w,36,5,TFT_DARKGREY);char key=line[i];if(!aiNumbers&&!aiCaps)key=tolower((unsigned char)key);label(String(key),x+i*(w+gap)+w/2-3,y+8,TFT_BLACK,TFT_WHITE,2);}}
  roundButton(4,438,48,40,aiCaps?"SHIFT":"shift",TFT_BLACK);
  roundButton(55,438,39,40,aiNumbers?"ABC":"123",TFT_BLACK);
  roundButton(97,438,116,40,"SPACE",TFT_WHITE,TFT_BLACK);
  roundButton(216,438,50,40,"BACK",TFT_BLACK);
  roundButton(269,438,47,40,"ASK",tft.color565(91,70,230));
}
void drawStore(){
  nav("App Store"); label("Discover",18,71,TFT_WHITE,TFT_BLACK,2);
  const char* app[]={"Messenger","Chess","Checkers","Notes"}; const char* detail[]={"Chat with another ESP32","Board game with Wi-Fi play","Local or Wi-Fi board game","Keep short notes"}; uint16_t c[]={TFT_DARKGREEN,TFT_BLUE,TFT_ORANGE,TFT_PURPLE};
  for(int i=0;i<4;i++){int y=99+i*72;tft.fillRoundRect(14,y,292,62,12,TFT_DARKGREY);tft.fillRoundRect(23,y+9,44,44,11,c[i]);label(app[i],78,y+10,TFT_WHITE,TFT_DARKGREY,2);label(detail[i],78,y+34,TFT_LIGHTGREY,TFT_DARKGREY);roundButton(230,y+16,60,28,storeNotice==i?"OPEN":"GET",storeNotice==i?TFT_GREEN:TFT_BLUE);}
  label("Built-in apps need no download.",55,401,TFT_LIGHTGREY,TFT_BLACK); }
bool readPhoto(int slot, uint16_t pixels[1024], uint8_t &size){if(!sdCardReady)return false;String path=String("/pixel_art_")+slot+".bin";File f=SD.open(path.c_str(),FILE_READ);if(!f)return false;bool ok=f.read(&size,1)==1&&(size==8||size==16||size==32);if(ok)ok=f.read((uint8_t*)pixels,size*size*2)==size*size*2;f.close();return ok;}
void drawPhotoSlot(int slot,int x,int y,int boxW,int boxH){tft.fillRoundRect(x,y,boxW,boxH,8,TFT_DARKGREY);uint16_t pixels[1024];uint8_t size=0;if(!readPhoto(slot,pixels,size)){label("EMPTY",x+12,y+boxH/2-4,TFT_LIGHTGREY,TFT_DARKGREY);return;}int scale=max(1,min((boxW-10)/size,(boxH-24)/size));int pw=size*scale,ph=size*scale,px=x+(boxW-pw)/2,py=y+4;for(int r=0;r<size;r++)for(int c=0;c<size;c++)tft.fillRect(px+c*scale,py+r*scale,scale,scale,pixels[r*size+c]);String title=String(slot+1);File n=SD.open((String("/pixel_art_")+slot+".txt").c_str(),FILE_READ);if(n){title=n.readString();title.trim();n.close();}label(title.substring(0,16),x+7,y+boxH-15,TFT_WHITE,TFT_DARKGREY);}
void drawPhotos(){nav("Drawing");label("Saved pixel art",72,68,TFT_WHITE,TFT_BLACK,2);if(!sdCardReady){label("Insert a microSD card to see saved art.",20,112,TFT_ORANGE,TFT_BLACK);return;}if(selectedPhoto>=0){drawPhotoSlot(selectedPhoto,36,95,248,248);roundButton(72,370,176,40,"BACK TO GALLERY",TFT_BLUE);roundButton(72,420,176,36,"DELETE THIS ART",TFT_RED);return;}for(int i=0;i<6;i++)drawPhotoSlot(i,15+(i%2)*150,100+(i/2)*96,140,86);roundButton(72,405,176,38,"NEW PIXEL ART",TFT_PURPLE);}
uint16_t pixelColor(int i){
  // Nine hue rows run bright-to-dark (red through pink); row ten is gray.
  if(i>=144){uint8_t v=(i-144)*255/15;return tft.color565(v,v,v);}
  uint8_t band=i/16,shade=i%16;float h=band*40.0f;float v=1.0f-shade*0.045f;float s=0.82f;float c=v*s,x=c*(1-fabs(fmod(h/60.0f,2)-1)),m=v-c;float r=0,g=0,b=0;
  if(h<60){r=c;g=x;}else if(h<120){r=x;g=c;}else if(h<180){g=c;b=x;}else if(h<240){g=x;b=c;}else if(h<300){r=x;b=c;}else{r=c;b=x;}
  return tft.color565((uint8_t)((r+m)*255),(uint8_t)((g+m)*255),(uint8_t)((b+m)*255));
}
void pixelSnapshot(uint16_t *to){memcpy(to,pixelCanvas,sizeof(pixelCanvas));}
void pixelPushUndo(){
  if(pixelUndoCount >= 7){
    memmove(pixelUndo[0], pixelUndo[1], sizeof(pixelUndo[0]) * 6);
    pixelUndoCount = 6;
  }
  pixelSnapshot(pixelUndo[pixelUndoCount++]);
  pixelRedoCount = 0;
}
void pixelPushRedo(){
  if(pixelRedoCount >= 7){
    memmove(pixelRedo[0], pixelRedo[1], sizeof(pixelRedo[0]) * 6);
    pixelRedoCount = 6;
  }
  // Save the picture currently on screen before Undo restores an older one.
  pixelSnapshot(pixelRedo[pixelRedoCount++]);
}
// These helpers touch only the canvas square or button that actually changed.
void drawPixelCell(int index){int px=index%16,py=index/16;tft.fillRect(8+px*19,65+py*19,19,19,pixelCanvas[index]);}
void drawPixelCanvas(){for(int i=0;i<256;i++)drawPixelCell(i);}
// Restore a history picture without repainting the whole Pixel Studio page.
// Only cells whose color really changed are sent to the display.
void pixelRestoreCanvas(const uint16_t *snapshot){
  for(int i=0;i<256;i++){
    if(pixelCanvas[i]!=snapshot[i]){
      pixelCanvas[i]=snapshot[i];
      drawPixelCell(i);
    }
  }
}
void drawPixelPickControl(){roundButton(140,383,38,36,"PICK",pixelEye?TFT_GREEN:TFT_DARKGREY);}
void drawPixelEraseControl(){roundButton(181,383,47,36,"ERASE",pixelErase?TFT_RED:TFT_DARKGREY);}
void drawPixelUndoControl(){roundButton(48,383,43,36,"UNDO",TFT_DARKGREY);}
void drawPixelRedoControl(){roundButton(94,383,43,36,"REDO",TFT_DARKGREY);}
void pixelStrokeTo(int px,int py){
  if(px<0||px>15||py<0||py>15)return;
  if(pixelEye){int index=py*16+px;pixelSelected=pixelCanvas[index];pixelEye=false;pixelStrokeActive=false;tft.fillRoundRect(11,385,32,32,7,pixelSelected);tft.drawRoundRect(11,385,32,32,7,TFT_WHITE);drawPixelPickControl();return;}
  if(!pixelStrokeActive){pixelPushUndo();pixelStrokeActive=true;pixelLastX=px;pixelLastY=py;}
  int x0=pixelLastX,y0=pixelLastY,dx=abs(px-x0),sx=x0<px?1:-1,dy=-abs(py-y0),sy=y0<py?1:-1,err=dx+dy;
  while(true){int index=y0*16+x0;uint16_t color=pixelErase?TFT_BLACK:pixelSelected;if(pixelCanvas[index]!=color){pixelCanvas[index]=color;drawPixelCell(index);}if(x0==px&&y0==py)break;int e2=2*err;if(e2>=dy){err+=dy;x0+=sx;}if(e2<=dx){err+=dx;y0+=sy;}}
  pixelLastX=px;pixelLastY=py;
}
void pixelFlood(int sx,int sy,uint16_t replacement){uint16_t old=pixelCanvas[sy*16+sx];if(old==replacement)return;pixelCanvas[sy*16+sx]=replacement;bool changed=true;while(changed){changed=false;for(int y=0;y<16;y++)for(int x=0;x<16;x++)if(pixelCanvas[y*16+x]==old){bool near=(x&&pixelCanvas[y*16+x-1]==replacement)||(x<15&&pixelCanvas[y*16+x+1]==replacement)||(y&&pixelCanvas[(y-1)*16+x]==replacement)||(y<15&&pixelCanvas[(y+1)*16+x]==replacement);if(near){pixelCanvas[y*16+x]=replacement;changed=true;}}}}
void drawPixelStudio(){
  nav(pixelPalette ? "Pixel colors" : "Pixel Studio");
  if(pixelPalette){
    label("160 colors - tap one to paint with it",23,68,TFT_LIGHTGREY,TFT_BLACK);
    for(int i=0;i<160;i++){int x=(i%16)*20,y=92+(i/16)*26;uint16_t c=pixelColor(i);tft.fillRect(x,y,20,26,c);if(c==pixelSelected)tft.drawRect(x+1,y+1,18,24,TFT_WHITE);}
    label("Each color row goes light to dark. Last row: black to white.",10,365,TFT_LIGHTGREY,TFT_BLACK);
    roundButton(55,410,210,42,"BACK TO PIXEL ART",TFT_BLUE);
    return;
  }
  // Draw a clean 16 by 16 canvas with no visible white grid lines.
  // Individual taps repaint only one 19-pixel square below.
  tft.fillRect(8,65,304,304,TFT_BLACK);
  drawPixelCanvas();
  tft.fillRoundRect(5,377,310,48,10,tft.color565(42,42,47));
  tft.fillRoundRect(11,385,32,32,7,pixelSelected);tft.drawRoundRect(11,385,32,32,7,TFT_WHITE);
  drawPixelUndoControl();
  drawPixelRedoControl();
  drawPixelPickControl();
  drawPixelEraseControl();
  roundButton(231,383,38,36,"FILL",TFT_BLUE);
  roundButton(272,383,40,36,"COLOR",TFT_PURPLE);
  roundButton(8,434,70,37,"SAVE",TFT_GREEN);
  roundButton(82,434,82,37,"PHOTOS",TFT_BLUE);
  roundButton(168,434,55,37,"NEW",TFT_PURPLE);
  label(pixelName.substring(0,14),229,448,TFT_WHITE,TFT_BLACK);
}
void drawPixelName(){
  nav("Name picture");
  tft.fillRoundRect(12,66,296,52,12,TFT_WHITE);
  String shown=pixelName.substring(max(0,(int)pixelName.length()-28));
  label(shown,23,84,TFT_BLACK,TFT_WHITE,2);
  // Same key positions and modes as the Messenger text keyboard.
  tft.fillRect(0,326,320,154,TFT_LIGHTGREY);
  const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
  const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
  for(int r=0;r<3;r++){const char* line=pixelNameNumbers?digits[r]:letters[r];int n=strlen(line),gap=1,w=(320-(n-1)*gap)/n,x=(320-(n*(w+gap)-gap))/2,y=326+r*37;for(int i=0;i<n;i++){tft.fillRoundRect(x+i*(w+gap),y,w,36,5,TFT_WHITE);tft.drawRoundRect(x+i*(w+gap),y,w,36,5,TFT_DARKGREY);char key=line[i];if(!pixelNameNumbers&&!pixelNameCaps)key=tolower((unsigned char)key);label(String(key),x+i*(w+gap)+w/2-3,y+8,TFT_BLACK,TFT_WHITE,2);}}
  roundButton(4,438,48,40,pixelNameCaps?"SHIFT":"shift",TFT_BLACK);
  roundButton(55,438,39,40,pixelNameNumbers?"ABC":"123",TFT_BLACK);
  roundButton(97,438,116,40,"SPACE",TFT_WHITE,TFT_BLACK);
  roundButton(216,438,50,40,"BACK",TFT_BLACK);
  roundButton(269,438,47,40,"SAVE",TFT_GREEN);
}
void savePixelArt(){
  if(!sdCardReady){addNotification("Insert microSD to save pixel art");return;}
  int slot=-1;
  for(int i=0;i<PIXEL_ART_SLOTS;i++){uint16_t p[1024];uint8_t s;if(!readPhoto(i,p,s)){slot=i;break;}}
  if(slot<0){addNotification("Pixel Gallery is full - delete art first");return;}
  String path=String("/pixel_art_")+slot+".bin";
  SD.remove(path.c_str());
  File f=SD.open(path.c_str(),FILE_WRITE);
  if(!f){addNotification("Could not save pixel art");return;}
  uint8_t size=16; f.write(&size,1); f.write((uint8_t*)pixelCanvas,512); f.close();
  String namePath=String("/pixel_art_")+slot+".txt";
  SD.remove(namePath.c_str());
  File n=SD.open(namePath.c_str(),FILE_WRITE);if(n){n.print(pixelName);n.close();}
  addNotification("Saved "+pixelName+" to Pixel Gallery");
}
void savePixelName(int slot){
  if(!sdCardReady || slot<0 || slot>=PIXEL_ART_SLOTS)return;
  String namePath=String("/pixel_art_")+slot+".txt";
  SD.remove(namePath.c_str());
  File n=SD.open(namePath.c_str(),FILE_WRITE);
  if(n){n.print(pixelName);n.close();addNotification("Renamed pixel art to "+pixelName);}
  else addNotification("Could not rename pixel art");
}
void drawFiles(){
  nav("Photos");
  if(!sdCardReady){label("microSD card not found",42,90,TFT_RED,TFT_BLACK,2);label("Insert the card, then open Files again.",24,128,TFT_LIGHTGREY,TFT_BLACK);return;}
  if(fileGallerySelected>=0){
    label("Pixel Gallery",85,68,TFT_WHITE,TFT_BLACK,2);
    drawPhotoSlot(fileGallerySelected,36,95,248,248);
    roundButton(20,370,86,38,"BACK",TFT_BLUE);
    roundButton(116,370,88,38,"RENAME",TFT_PURPLE);
    roundButton(214,370,86,38,"DELETE",TFT_RED);
    roundButton(56,423,208,38,"NEW PIXEL ART",TFT_GREEN);
    return;
  }
  label("Pixel Gallery",98,68,TFT_WHITE,TFT_BLACK,2);
  float freeGb=(SD.totalBytes()-SD.usedBytes())/1073741824.0f;
  label(String(freeGb,2)+" GB free",116,91,TFT_GREEN,TFT_BLACK);
  int first=fileGalleryPage*6;
  for(int i=0;i<6;i++)drawPhotoSlot(first+i,15+(i%2)*150,110+(i/2)*91,140,82);
  roundButton(12,392,62,34,"PREV",fileGalleryPage>0?TFT_BLUE:TFT_DARKGREY);
  roundButton(82,392,156,34,"NEW PIXEL ART",TFT_GREEN);
  roundButton(246,392,62,34,"NEXT",fileGalleryPage<((PIXEL_ART_SLOTS-1)/6)?TFT_BLUE:TFT_DARKGREY);
  label(String("Page ")+(fileGalleryPage+1)+" of "+String((PIXEL_ART_SLOTS+5)/6),106,439,TFT_LIGHTGREY,TFT_BLACK);
}
void drawScreenTime(){nav("Screen Time");label("Today",126,90,TFT_WHITE,TFT_BLACK,2); uint32_t mins=(millis()-launchedAt)/60000; label(String(mins)+" minutes",88,142,TFT_GREEN,TFT_BLACK,4);label("Time this phone has been switched on",43,203,TFT_LIGHTGREY,TFT_BLACK);}
void drawDevice(){nav("About");label("ESP32 Screen Phone",52,90,TFT_WHITE,TFT_BLACK,2);label("320 x 480 touch display",55,136,TFT_LIGHTGREY,TFT_BLACK);label("Wi-Fi: "+String(WiFi.status()==WL_CONNECTED?WiFi.localIP().toString():"Not connected"),23,169,TFT_GREEN,TFT_BLACK);label(sdCardReady?"Storage: microSD available":"Storage: insert microSD",23,203,sdCardReady?TFT_GREEN:TFT_ORANGE,TFT_BLACK);}
void drawCalcDisplay(){
  // Only this display rectangle changes when a calculator key is tapped.
  tft.fillRoundRect(12,68,296,67,12,TFT_BLACK);
  String shown=calc.length()?calc:"0";
  if(shown.length()>15)shown=shown.substring(shown.length()-15);
  tft.setTextDatum(TR_DATUM);
  tft.setTextColor(TFT_WHITE,TFT_BLACK);
  tft.setTextSize(3);
  tft.drawString(shown,294,86);
  tft.setTextDatum(TL_DATUM);
}
void calculatorKey(const String &key){
  if(key=="C"){calc="0";calcStored=0;calcOperation=0;calcFreshNumber=true;}
  else if(key=="+/-"){if(calc!="0"){if(calc.charAt(0)=='-')calc.remove(0,1);else calc="-"+calc;}}
  else if(key=="%") { calc=String(calc.toFloat()/100.0f,4); calcFreshNumber=true; }
  else if(key=="+"||key=="-"||key=="x"||key=="/") { calcStored=calc.toFloat();calcOperation=key.charAt(0);calcFreshNumber=true; }
  else if(key=="="){
    float right=calc.toFloat(),answer=calcStored;
    if(calcOperation=='+')answer+=right; else if(calcOperation=='-')answer-=right; else if(calcOperation=='x')answer*=right; else if(calcOperation=='/'){if(right==0){calc="Error";calcOperation=0;calcFreshNumber=true;drawCalcDisplay();return;}answer/=right;}
    calc=String(answer,4);while(calc.indexOf('.')>=0&&calc.endsWith("0"))calc.remove(calc.length()-1);if(calc.endsWith("."))calc.remove(calc.length()-1);calcOperation=0;calcFreshNumber=true;
  } else {
    if(calcFreshNumber||calc=="0"){calc=key;calcFreshNumber=false;}else if(key=="."&&calc.indexOf('.')<0)calc+=key;else if(key!=".")calc+=key;
  }
  drawCalcDisplay();
}
void drawCalc(){
  nav("Calculator");
  drawCalcDisplay();
  const char* keys[]={"C","+/-","%","/","7","8","9","x","4","5","6","-","1","2","3","+","0",".","=","="};
  uint16_t keyColors[]={TFT_DARKGREY,TFT_DARKGREY,TFT_DARKGREY,TFT_ORANGE,TFT_DARKGREY,TFT_DARKGREY,TFT_DARKGREY,TFT_ORANGE,TFT_DARKGREY,TFT_DARKGREY,TFT_DARKGREY,TFT_ORANGE,TFT_DARKGREY,TFT_DARKGREY,TFT_DARKGREY,TFT_ORANGE,TFT_DARKGREY,TFT_DARKGREY,TFT_ORANGE,TFT_ORANGE};
  for(int row=0;row<5;row++)for(int col=0;col<4;col++){int i=row*4+col;roundButton(15+col*76,151+row*57,62,47,keys[i],keyColors[i]);}
}
// Notes uses the same typing layout as Messenger: Shift, 123/ABC, Space,
// Back, and a right-side action key.  These helpers let typing redraw only
// the white note area instead of flashing the whole page or keyboard.
void drawNoteInput(){
  tft.fillRoundRect(12,66,296,104,12,TFT_WHITE);
  label("My Note",25,77,TFT_ORANGE,TFT_WHITE,2);
  String shown=noteText.substring(max(0,(int)noteText.length()-42));
  label(shown,24,116,TFT_BLACK,TFT_WHITE,2);
}
void drawNoteKeyboard(){
  tft.fillRect(0,326,320,154,TFT_LIGHTGREY);
  const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
  const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
  for(int r=0;r<3;r++){
    const char* line=noteNumbers?digits[r]:letters[r];
    int n=strlen(line),gap=2,w=(320-4-(n-1)*gap)/n,x=(320-(n*(w+gap)-gap))/2,y=328+r*35;
    for(int i=0;i<n;i++){
      tft.fillRoundRect(x+i*(w+gap),y,w,33,4,TFT_WHITE);
      tft.drawRoundRect(x+i*(w+gap),y,w,33,4,TFT_DARKGREY);
      char key=line[i]; if(!noteNumbers&&!noteCaps)key=tolower((unsigned char)key);
      label(String(key),x+i*(w+gap)+w/2-3,y+8,TFT_BLACK,TFT_WHITE,2);
    }
  }
  roundButton(4,438,48,40,noteCaps?"SHIFT":"shift",TFT_BLACK);
  roundButton(55,438,39,40,noteNumbers?"ABC":"123",TFT_BLACK);
  roundButton(97,438,116,40,"SPACE",TFT_WHITE,TFT_BLACK);
  roundButton(216,438,50,40,"BACK",TFT_BLACK);
  roundButton(269,438,47,40,"SAVE",TFT_BLUE);
}
void drawNotes(){
  nav("Notes");
  drawNoteInput();
  label("Your note is saved on the microSD card.",35,210,TFT_LIGHTGREY,TFT_BLACK);
  drawNoteKeyboard();
}
void drawNotifications(){
  nav("Notifications");
  label("Notifications",22,72,TFT_WHITE,TFT_BLACK,3);
  label(notificationCount ? "Latest alerts" : "No notifications yet",22,101,TFT_LIGHTGREY,TFT_BLACK);
  uint16_t bg=tft.color565(34,34,38);
  int shown=min(4,notificationCount);
  for(int row=0;row<shown;row++){
    int index=notificationCount-1-row, y=119+row*78;
    tft.fillRoundRect(12,y,296,68,16,bg);
    // A black circle with a white ! marks each alert.
    tft.fillCircle(42, y+34, 17, TFT_BLACK);
    tft.setTextDatum(MC_DATUM);
    tft.setTextColor(TFT_WHITE, TFT_BLACK);
    tft.setTextSize(2);
    tft.drawString("!", 42, y+34);
    tft.setTextDatum(TL_DATUM);
    label("Messenger",72,y+12,TFT_WHITE,bg,2);
    label(notificationTexts[index].substring(0,34),72,y+39,TFT_LIGHTGREY,bg);
    uint32_t ageSeconds = (millis() - notificationReceivedAt[index]) / 1000;
    String age = ageSeconds < 2 ? "now" : String(ageSeconds) + "s";
    label(age,263,y+14,TFT_LIGHTGREY,bg);
  }
  if(notificationCount>4) label("Showing the latest 4 alerts",69,440,TFT_LIGHTGREY,TFT_BLACK);
  lastNotificationDraw = millis() / 1000;
}

// Only the tiny relative-time fields change once per second. This avoids the
// visible flash caused by repainting the whole Notifications page every tick.
void refreshNotificationAges() {
  if (page != NOTIFICATIONS) return;
  const uint16_t bg = tft.color565(34,34,38);
  int shown = min(4, notificationCount);
  for (int row = 0; row < shown; row++) {
    int index = notificationCount - 1 - row;
    int y = 119 + row * 78;
    tft.fillRect(258, y + 10, 42, 17, bg);
    uint32_t ageSeconds = (millis() - notificationReceivedAt[index]) / 1000;
    String age = ageSeconds < 2 ? "now" : String(ageSeconds) + "s";
    label(age, 263, y + 14, TFT_LIGHTGREY, bg);
  }
  lastNotificationDraw = millis() / 1000;
}
void refreshClock(){
  tft.fillRect(34,155,260,55,TFT_BLACK);
  label(networkTimeText(true),45,170,TFT_CYAN,TFT_BLACK,4);
  lastClockDraw=millis()/1000;
}
void drawClock(){
  nav("Clock");
  label("CLOCK",111,105,TFT_WHITE,TFT_BLACK,3);
  refreshClock();
  label(networkTimeReady?"Real time from Wi-Fi (Eastern Time)":"Waiting for Wi-Fi time",30,250,TFT_LIGHTGREY,TFT_BLACK);
}
String jsonValue(const String &s,const String &key){
  int p=s.indexOf("\""+key+"\":");
  if(p<0)return "";
  p+=key.length()+3;
  int e=s.indexOf(',',p);
  if(e<0)e=s.indexOf('}',p);
  String v=s.substring(p,e);
  v.replace("\"","");
  return v;
}
// Read a number only from one named JSON object.  Open-Meteo also sends units
// and dates elsewhere in its reply, so a whole-reply search can select a date.
String jsonObjectValue(const String &json,const String &objectName,const String &key){
  int objectAt=json.indexOf("\""+objectName+"\":{");
  if(objectAt<0)return "";
  int objectEnd=json.indexOf('}',objectAt);
  if(objectEnd<0)return "";
  String object=json.substring(objectAt,objectEnd+1);
  return jsonValue(object,key);
}
String jsonFirstArrayValue(const String &json,const String &objectName,const String &key){
  int objectAt=json.indexOf("\""+objectName+"\":{");
  if(objectAt<0)return "";
  int objectEnd=json.indexOf('}',objectAt);
  if(objectEnd<0)return "";
  int keyAt=json.indexOf("\""+key+"\":[",objectAt);
  if(keyAt<0||keyAt>objectEnd)return "";
  int start=keyAt+key.length()+4;
  int end=json.indexOf(',',start);
  if(end<0||end>objectEnd)end=json.indexOf(']',start);
  if(end<0)return "";
  return json.substring(start,end);
}
String weatherText(){
  if(weatherCode < 0) return weatherNow;
  if(weatherCode == 0) return "Clear sky";
  if(weatherCode <= 3) return "Partly cloudy";
  if(weatherCode <= 48) return "Foggy";
  if(weatherCode <= 67) return "Rain showers";
  if(weatherCode <= 77) return "Snow showers";
  if(weatherCode <= 82) return "Heavy showers";
  return "Thunderstorms";
}
void drawWeatherSymbol(int cx,int cy){
  bool rainy=weatherCode>=51 && weatherCode<=82;
  bool cloudy=weatherCode>=1 || weatherCode<0;
  if(!rainy || cloudy){
    tft.fillCircle(cx-13,cy-12,19,TFT_YELLOW);
    for(int a=0;a<8;a++){float r=a*0.785f;tft.drawLine(cx-13+(int)(25*cos(r)),cy-12+(int)(25*sin(r)),cx-13+(int)(31*cos(r)),cy-12+(int)(31*sin(r)),TFT_YELLOW);}
  }
  if(cloudy){tft.fillCircle(cx-3,cy+4,15,TFT_WHITE);tft.fillCircle(cx+14,cy+5,20,TFT_WHITE);tft.fillCircle(cx+31,cy+10,12,TFT_WHITE);tft.fillRect(cx-4,cy+5,36,17,TFT_WHITE);}
  if(rainy)for(int i=0;i<3;i++)tft.drawLine(cx+i*13,cy+30,cx-4+i*13,cy+40,TFT_CYAN);
}
void refreshWeather(){
  if(WiFi.status()!=WL_CONNECTED){weatherNow="Connect to Wi-Fi first";weatherPlace="";weatherCode=-1;drawWeather();return;}
  HTTPClient http;
  // Weather is optional. Keep a failed hotspot/Internet lookup from freezing
  // the screen for seven seconds after the user taps Refresh.
  http.setConnectTimeout(900);
  http.setTimeout(1800);
  if(!http.begin("http://ip-api.com/json/?fields=status,city,lat,lon")){weatherNow="Location lookup failed";drawWeather();return;}
  int status=http.GET();String place=status==200?http.getString():"";http.end();
  String lat=jsonValue(place,"lat"),lon=jsonValue(place,"lon");weatherPlace=jsonValue(place,"city");
  if(!lat.length()||!lon.length()){weatherNow="Location unavailable";drawWeather();return;}
  String url="http://api.open-meteo.com/v1/forecast?latitude="+lat+"&longitude="+lon+"&current=temperature_2m,weather_code&daily=temperature_2m_max,temperature_2m_min&temperature_unit=fahrenheit&timezone=auto";
  if(!http.begin(url)){weatherNow="Weather service unavailable";drawWeather();return;}
  status=http.GET();String data=status==200?http.getString():"";http.end();
  // Use the actual current and daily data objects, never the matching unit labels.
  String temp=jsonObjectValue(data,"current","temperature_2m");
  if(!temp.length()){weatherNow="No weather reply";drawWeather();return;}
  weatherNow=temp+" F";
  weatherCode=jsonObjectValue(data,"current","weather_code").toInt();
  weatherHigh=jsonFirstArrayValue(data,"daily","temperature_2m_max");
  weatherLow=jsonFirstArrayValue(data,"daily","temperature_2m_min");
  if(!weatherHigh.length())weatherHigh="--";
  if(!weatherLow.length())weatherLow="--";
  drawWeather();
}
void drawWeather(){
  nav("Weather");
  const uint16_t navy=tft.color565(13,25,62), blue=tft.color565(35,91,204), cardBlue=tft.color565(55,111,220), panel=tft.color565(28,39,74);
  // This complete scene is drawn only on entry or after the Refresh button is tapped.
  tft.fillRect(0,56,320,424,navy);
  tft.fillRoundRect(12,70,296,220,25,blue);
  tft.fillRoundRect(12,70,296,76,25,cardBlue);
  label(weatherPlace.length()?weatherPlace:"Local weather",27,87,TFT_WHITE,cardBlue,2);
  label(weatherText(),27,116,TFT_WHITE,cardBlue);
  String temp=weatherNow;int sp=temp.indexOf(" F");if(sp>0)temp=temp.substring(0,sp)+"°F";
  // A temperature uses the large type only after a real weather reply arrives.
  // The longer loading/error messages get their own two-line area on the left,
  // while the illustration stays on the right, so neither can cover the other.
  bool hasTemperature = weatherCode >= 0 && sp > 0;
  if (hasTemperature) {
    label(temp,25,155,TFT_WHITE,blue,4);
    label("NOW",28,218,TFT_CYAN,blue);
  } else {
    String first = temp;
    String second = "";
    int cut = first.lastIndexOf(' ', 20);
    if (cut > 0 && first.length() > 20) {
      second = first.substring(cut + 1);
      first = first.substring(0, cut);
    }
    label(first,25,160,TFT_WHITE,blue,2);
    if (second.length()) label(second,25,187,TFT_WHITE,blue,2);
    label("Tap the button below",25,228,TFT_CYAN,blue);
  }
  drawWeatherSymbol(246,164);
  tft.fillRoundRect(12,303,142,75,17,panel);
  tft.fillRoundRect(166,303,142,75,17,panel);
  label("TODAY'S HIGH",26,318,TFT_LIGHTGREY,panel);
  label(weatherHigh+"°",27,342,TFT_WHITE,panel,3);
  label("TONIGHT'S LOW",180,318,TFT_LIGHTGREY,panel);
  label(weatherLow+"°",181,342,TFT_WHITE,panel,3);
  tft.fillRoundRect(12,391,296,42,14,panel);
  label(WiFi.status()==WL_CONNECTED?"Uses your Wi-Fi location":"Connect Wi-Fi in Settings to update",25,406,WiFi.status()==WL_CONNECTED?TFT_CYAN:TFT_ORANGE,panel);
  roundButton(42,443,236,30,"REFRESH WEATHER",TFT_BLUE);
}

void resetSudoku(bool nextMap=false){ if(nextMap) sudokuMap=(sudokuMap+1)%3; memcpy(sudokuPuzzle,sudokuPuzzles[sudokuMap],sizeof(sudokuPuzzle)); memcpy(sudokuAnswer,sudokuAnswers[sudokuMap],sizeof(sudokuAnswer)); memcpy(sudokuBoard,sudokuPuzzle,sizeof(sudokuBoard)); sudokuCell=-1; sudokuMistakes=0; sudokuStarted=false; }
void sendSudokuState(){
  if(!gamePeer || !gamePeer.connected()) return;
  gamePeer.printf("P,%d,%d,%d\\n",sudokuMap,sudokuMistakes,gameDone?1:0);
  for(int i=0;i<81;i++) if(sudokuBoard[i]) gamePeer.printf("S,%d,%d\\n",i,sudokuBoard[i]);
  if(gameDone && sudokuMistakes>=3) gamePeer.print("L\\n");
  else if(gameDone) gamePeer.print("F\\n");
}
void resetGames(){resetSudoku();const char*c[]={"rnbqkbnr","pppppppp","........","........","........","........","PPPPPPPP","RNBQKBNR"};for(int y=0;y<8;y++)for(int x=0;x<8;x++){chess[y][x]=c[y][x];checkers[y][x]=((y<3||y>4)&&((x+y)&1))?(y<3?'r':'b'):'.';}pickedX=pickedY=-1;whiteTurn=redTurn=true;gameDone=false;result="";}
void chessSquare(int x,int y){
  int s=38,ox=8,oy=112,cx=ox+x*s+19,cy=oy+y*s+19;
  uint16_t b=(x+y)&1?TFT_DARKGREEN:TFT_LIGHTGREY;
  tft.fillRect(ox+x*s,oy+y*s,s,s,b);
  if(x==pickedX&&y==pickedY)tft.drawRect(ox+x*s+2,oy+y*s+2,s-4,s-4,TFT_YELLOW);
  char p=chess[y][x]; if(p=='.')return;
  uint16_t pc=isupper(p)?TFT_WHITE:TFT_BLACK;
  uint16_t edge=isupper(p)?TFT_DARKGREY:TFT_LIGHTGREY;
  char kind=tolower((unsigned char)p);
  // Detailed, outlined silhouettes: the shapes match the familiar rook, knight,
  // bishop, queen, king, and pawn appearance instead of letter-like markers.
  tft.fillRoundRect(cx-14,cy+10,28,6,3,pc);
  tft.drawRoundRect(cx-14,cy+10,28,6,3,edge);
  if(kind=='p'){
    tft.fillCircle(cx,cy-7,6,pc); tft.drawCircle(cx,cy-7,6,edge);
    tft.fillTriangle(cx-8,cy+9,cx+8,cy+9,cx,cy-1,pc);
  } else if(kind=='r'){
    tft.fillRect(cx-10,cy-7,20,16,pc); tft.drawRect(cx-10,cy-7,20,16,edge);
    tft.fillRect(cx-11,cy-11,5,6,pc); tft.fillRect(cx-2,cy-11,5,6,pc); tft.fillRect(cx+6,cy-11,5,6,pc);
    tft.drawFastHLine(cx-10,cy-4,20,edge);
  } else if(kind=='n'){
    tft.fillTriangle(cx-10,cy+9,cx+10,cy+9,cx+6,cy-12,pc);
    tft.fillCircle(cx+3,cy-6,6,pc); tft.drawPixel(cx+5,cy-8,edge);
    tft.drawLine(cx-10,cy+9,cx+6,cy-12,edge); tft.drawLine(cx+6,cy-12,cx+10,cy+9,edge);
  } else if(kind=='b'){
    tft.fillCircle(cx,cy-9,6,pc); tft.drawLine(cx-3,cy-12,cx+3,cy-6,edge);
    tft.fillTriangle(cx-9,cy+9,cx+9,cy+9,cx,cy-3,pc); tft.drawTriangle(cx-9,cy+9,cx+9,cy+9,cx,cy-3,edge);
  } else if(kind=='q'){
    tft.fillCircle(cx-8,cy-10,3,pc); tft.fillCircle(cx,cy-13,3,pc); tft.fillCircle(cx+8,cy-10,3,pc);
    tft.fillTriangle(cx-11,cy+9,cx+11,cy+9,cx,cy-5,pc); tft.drawTriangle(cx-11,cy+9,cx+11,cy+9,cx,cy-5,edge);
    tft.drawFastHLine(cx-9,cy+5,18,edge);
  } else {
    tft.fillRect(cx-2,cy-14,4,13,pc); tft.fillRect(cx-7,cy-10,14,4,pc);
    tft.fillTriangle(cx-10,cy+9,cx+10,cy+9,cx,cy-3,pc); tft.drawTriangle(cx-10,cy+9,cx+10,cy+9,cx,cy-3,edge);
    tft.drawFastHLine(cx-7,cy-10,14,edge);
  }
}
void checkerSquare(int x,int y){int s=38,ox=8,oy=112;uint16_t b=(x+y)&1?TFT_DARKGREY:TFT_LIGHTGREY;tft.fillRect(ox+x*s,oy+y*s,s,s,b);if(x==pickedX&&y==pickedY)tft.drawRect(ox+x*s+2,oy+y*s+2,s-4,s-4,TFT_YELLOW);char p=checkers[y][x];if(p!='.'){int cx=ox+x*s+19,cy=oy+y*s+19;uint16_t z=p=='r'?TFT_RED:TFT_BLUE;tft.fillCircle(cx,cy+2,14,TFT_BLACK);tft.fillCircle(cx,cy,13,z);tft.drawCircle(cx,cy,10,p=='r'?TFT_YELLOW:TFT_CYAN);}}
void gameTop(const String&s){
  nav(s);
  roundButton(78,61,76,34,"2 PLAY",gameMode==TWO_PLAYER_MODE?TFT_BLUE:TFT_DARKGREY);
  roundButton(160,61,74,34,"AI",gameMode==AI_OFF_MODE?TFT_BLUE:TFT_DARKGREY);
  roundButton(240,61,72,34,"WI-FI",gameMode==WIFI_MODE?TFT_BLUE:TFT_DARKGREY);
  roundButton(10,426,300,42,"NEW GAME",TFT_GREEN);
}
void checkersStatus(){
  tft.fillRect(0,96,320,16,TFT_BLACK);
  label(gameDone?result:(redTurn?"Red's turn":"Blue's turn"),10,99,gameDone?TFT_YELLOW:TFT_WHITE,TFT_BLACK);
}
void drawCheckers(bool full){
  if(full){
    gameTop("Checkers");
    for(int y=0;y<8;y++)for(int x=0;x<8;x++)checkerSquare(x,y);
  }
  checkersStatus();
}
void drawSudoku(bool full){
  if(full){
    nav("Sudoku");
    label("Local pass-and-play puzzle",55,64,TFT_CYAN,TFT_BLACK,2);
    if(gameDone && sudokuMistakes >= 3) label("Round over - start a new puzzle",38,92,TFT_RED,TFT_BLACK,2);
    else label(String("Mistakes: ")+sudokuMistakes+" / 3",96,92,sudokuMistakes==0?TFT_WHITE:TFT_ORANGE,TFT_BLACK,2);
    const int ox=16,oy=112,s=32;
    for(int r=0;r<9;r++)for(int c=0;c<9;c++){
      int i=r*9+c; uint16_t bg=sudokuPuzzle[i]?tft.color565(48,48,55):tft.color565(24,24,29);
      if(i==sudokuCell) bg=tft.color565(45,84,145);
      tft.fillRect(ox+c*s,oy+r*s,s,s,bg);
      tft.drawRect(ox+c*s,oy+r*s,s,s,tft.color565(90,90,98));
      if(c%3==0)tft.drawFastVLine(ox+c*s,oy,288,TFT_WHITE);
      if(r%3==0)tft.drawFastHLine(ox,oy+r*s,288,TFT_WHITE);
      if(sudokuBoard[i]) label(String(sudokuBoard[i]),ox+c*s+11,oy+r*s+8,sudokuPuzzle[i]?TFT_WHITE:TFT_CYAN,bg,2);
    }
    tft.drawRect(ox,oy,288,288,TFT_WHITE);
    for(int n=1;n<=9;n++) roundButton(8+(n-1)*34,404,30,30,String(n),TFT_DARKGREY);
    roundButton(70,446,180,28,"NEW PUZZLE",TFT_BLUE);
  }
}
void sudokuTap(int x,int y){
  // This is a local puzzle: it does not host, join, or use Wi-Fi.
  if(gameDone){
    if(y>=446&&y<480){resetSudoku(true);gameDone=false;result="";drawSudoku();}
    return;
  }
  if(y>=112&&y<400&&x>=16&&x<304){int c=(x-16)/32,r=(y-112)/32,i=r*9+c;if(!sudokuPuzzle[i]){sudokuCell=i;drawSudoku();}return;}
  if(y>=404&&y<438&&sudokuCell>=0){int n=(x-8)/34+1;if(n<1||n>9)return;if(sudokuAnswer[sudokuCell]!=n){sudokuMistakes++; sudokuCell=-1; if(sudokuMistakes>=3){gameDone=true;result="3 mistakes - puzzle locked";addNotification("Sudoku locked after 3 mistakes");} drawSudoku();return;} sudokuBoard[sudokuCell]=n; sudokuCell=-1; bool complete=true;for(int i=0;i<81;i++)if(!sudokuBoard[i])complete=false;if(complete){gameDone=true;result="Puzzle complete!";addNotification("Sudoku puzzle complete!");}drawSudoku();return;}
  if(y>=446&&y<480){resetSudoku(true);gameDone=false;result="";drawSudoku();}
}
void drawGameWifi(){tft.fillScreen(TFT_BLACK);nav(gameType==CHESS_GAME?"Chess Wi-Fi":gameType==CHECKERS_GAME?"Checkers Wi-Fi":"Sudoku Wi-Fi");label(gameType==SUDOKU_GAME?"Race to solve the same puzzle":"Play on two ESP32 screens",44,107,TFT_WHITE,TFT_BLACK,2);roundButton(22,145,276,57,"HOST GAME",TFT_BLUE);roundButton(22,220,276,57,"JOIN SAVED IP",TFT_GREEN);roundButton(22,295,276,50,"OPEN MESSENGER SETUP",TFT_DARKGREY);label("IP: "+savedIp,64,375,TFT_LIGHTGREY,TFT_BLACK);}
void sendMove(int fx,int fy,int tx,int ty){if(gamePeer&&gamePeer.connected())gamePeer.printf("M,%d,%d,%d,%d\n",fx,fy,tx,ty);}

bool inside(int x,int y){return x>=0&&x<8&&y>=0&&y<8;}
bool sameChessSide(char a,char b){return a!='.'&&b!='.'&&(isupper((unsigned char)a)==isupper((unsigned char)b));}
bool chessClear(int fx,int fy,int tx,int ty){int dx=(tx>fx)-(tx<fx),dy=(ty>fy)-(ty<fy);for(fx+=dx,fy+=dy;fx!=tx||fy!=ty;fx+=dx,fy+=dy)if(chess[fy][fx]!='.')return false;return true;}
bool chessAttacked(int tx,int ty,bool byWhite){
  int pawnY=ty+(byWhite?1:-1); if(inside(tx-1,pawnY)&&chess[pawnY][tx-1]==(byWhite?'P':'p'))return true; if(inside(tx+1,pawnY)&&chess[pawnY][tx+1]==(byWhite?'P':'p'))return true;
  const int nx[]={1,2,2,1,-1,-2,-2,-1},ny[]={-2,-1,1,2,2,1,-1,-2}; for(int i=0;i<8;i++)if(inside(tx+nx[i],ty+ny[i])&&chess[ty+ny[i]][tx+nx[i]]==(byWhite?'N':'n'))return true;
  for(int d=0;d<8;d++){int dx=(d==0||d==1||d==7)?1:(d==3||d==4||d==5)?-1:0,dy=(d==1||d==2||d==3)?1:(d==5||d==6||d==7)?-1:0;for(int x=tx+dx,y=ty+dy;inside(x,y);x+=dx,y+=dy){char p=chess[y][x];if(p=='.')continue;if(isupper((unsigned char)p)==byWhite){char k=tolower((unsigned char)p);if((d%2==0&&(k=='r'||k=='q'))||(d%2==1&&(k=='b'||k=='q'))||(abs(x-tx)<=1&&abs(y-ty)<=1&&k=='k'))return true;}break;}}
  return false;
}
bool chessInCheck(bool white){for(int y=0;y<8;y++)for(int x=0;x<8;x++)if(chess[y][x]==(white?'K':'k'))return chessAttacked(x,y,!white);return true;}
bool chessShapeOK(int fx,int fy,int tx,int ty){
  if(!inside(fx,fy)||!inside(tx,ty)||(fx==tx&&fy==ty))return false;char p=chess[fy][fx],q=chess[ty][tx];if(p=='.'||sameChessSide(p,q)||tolower((unsigned char)q)=='k')return false;int dx=tx-fx,dy=ty-fy,ax=abs(dx),ay=abs(dy);char k=tolower((unsigned char)p);
  if(k=='p'){int dir=isupper((unsigned char)p)?-1:1,start=isupper((unsigned char)p)?6:1;if(dx==0&&dy==dir&&q=='.')return true;if(dx==0&&dy==2*dir&&fy==start&&q=='.'&&chess[fy+dir][fx]=='.')return true;return ax==1&&dy==dir&&q!='.';}
  if(k=='n')return (ax==1&&ay==2)||(ax==2&&ay==1); if(k=='b')return ax==ay&&chessClear(fx,fy,tx,ty); if(k=='r')return (ax==0||ay==0)&&chessClear(fx,fy,tx,ty); if(k=='q')return (ax==ay||ax==0||ay==0)&&chessClear(fx,fy,tx,ty); if(k=='k')return ax<=1&&ay<=1; return false;
}
bool chessLegal(int fx,int fy,int tx,int ty){if(!chessShapeOK(fx,fy,tx,ty))return false;char save[8][8];memcpy(save,chess,sizeof(chess));char p=chess[fy][fx];chess[ty][tx]=p;chess[fy][fx]='.';bool ok=!chessInCheck(isupper((unsigned char)p));memcpy(chess,save,sizeof(chess));return ok;}
bool chessHasMove(bool white){for(int y=0;y<8;y++)for(int x=0;x<8;x++)if(chess[y][x]!='.'&&(isupper((unsigned char)chess[y][x])==white))for(int ty=0;ty<8;ty++)for(int tx=0;tx<8;tx++)if(chessLegal(x,y,tx,ty))return true;return false;}
void chessStatus(){tft.fillRect(0,96,320,16,TFT_BLACK);label(gameDone?result:(whiteTurn?"White's turn":"Black's turn"),10,99,gameDone?TFT_YELLOW:TFT_WHITE,TFT_BLACK);}
void drawChess(bool full){if(full){gameTop("Chess");for(int y=0;y<8;y++)for(int x=0;x<8;x++)chessSquare(x,y);}chessStatus();}
void playChessMove(int fx,int fy,int tx,int ty,bool transmit){
  char moving=chess[fy][fx];
  chess[ty][tx]=moving;
  chess[fy][fx]='.';
  pickedX=pickedY=-1;
  whiteTurn=!whiteTurn;
  if(chessInCheck(whiteTurn)){
    if(!chessHasMove(whiteTurn)){gameDone=true;result=whiteTurn?"Checkmate - Black wins!":"Checkmate - White wins!";}
    else result=whiteTurn?"White is in check":"Black is in check";
  }else if(!chessHasMove(whiteTurn)){gameDone=true;result="Stalemate";}
  else result="";
  // A move changes only these two squares and the small status strip.
  chessSquare(fx,fy);
  chessSquare(tx,ty);
  chessStatus();
  if(transmit)sendMove(fx,fy,tx,ty);
}
void chessTap(int x,int y){
  // In AI mode the person is White, so Black is reserved for the computer.
  if(gameDone||y<112||y>=416||(gameMode==AI_OFF_MODE&&!whiteTurn))return;
  int bx=(x-8)/38,by=(y-112)/38;if(!inside(bx,by))return;
  if(pickedX<0){char p=chess[by][bx];if(p!='.'&&isupper((unsigned char)p)==whiteTurn){pickedX=bx;pickedY=by;chessSquare(bx,by);}return;}
  if(chessLegal(pickedX,pickedY,bx,by)){playChessMove(pickedX,pickedY,bx,by,true);return;}
  char p=chess[by][bx];int oldX=pickedX,oldY=pickedY;pickedX=pickedY=-1;chessSquare(oldX,oldY);
  if(p!='.'&&isupper((unsigned char)p)==whiteTurn){pickedX=bx;pickedY=by;chessSquare(bx,by);}
}

bool checkerRed(char p){return p=='r'||p=='R';} bool checkerKing(char p){return p=='R'||p=='B';}
bool checkerCaptureAt(int fx,int fy){char p=checkers[fy][fx];if(p=='.')return false;for(int dy=-1;dy<=1;dy+=2){if(!checkerKing(p)&&dy!=(checkerRed(p)?1:-1))continue;for(int dx=-1;dx<=1;dx+=2){int mx=fx+dx,my=fy+dy,tx=fx+2*dx,ty=fy+2*dy;if(inside(tx,ty)&&checkers[ty][tx]=='.'&&checkers[my][mx]!='.'&&checkerRed(checkers[my][mx])!=checkerRed(p))return true;}}return false;}
bool checkersAnyCapture(bool red){for(int y=0;y<8;y++)for(int x=0;x<8;x++)if(checkers[y][x]!='.'&&checkerRed(checkers[y][x])==red&&checkerCaptureAt(x,y))return true;return false;}
bool checkerMoveOK(int fx,int fy,int tx,int ty){if(!inside(fx,fy)||!inside(tx,ty)||checkers[ty][tx]!='.')return false;char p=checkers[fy][fx];if(p=='.')return false;int dx=abs(tx-fx),dy=ty-fy,ady=abs(dy);if(dx!=ady||(dx!=1&&dx!=2))return false;if(!checkerKing(p)&&dy!=(checkerRed(p)?dx:-dx))return false;if(dx==2){char mid=checkers[(fy+ty)/2][(fx+tx)/2];return mid!='.'&&checkerRed(mid)!=checkerRed(p);}return !checkersAnyCapture(checkerRed(p));}
bool checkerHasMove(bool red){for(int y=0;y<8;y++)for(int x=0;x<8;x++)if(checkers[y][x]!='.'&&checkerRed(checkers[y][x])==red)for(int ty=0;ty<8;ty++)for(int tx=0;tx<8;tx++)if(checkerMoveOK(x,y,tx,ty))return true;return false;}
void countCheckers(){int r=0,b=0;for(int y=0;y<8;y++)for(int x=0;x<8;x++){if(checkers[y][x]!='.'&&checkerRed(checkers[y][x]))r++;if(checkers[y][x]!='.'&&!checkerRed(checkers[y][x]))b++;}if(!r){gameDone=true;result="Blue wins!";}else if(!b){gameDone=true;result="Red wins!";}else if(!checkerHasMove(redTurn)){gameDone=true;result=redTurn?"Blue wins - Red is stuck":"Red wins - Blue is stuck";}}
void playCheckerMove(int fx,int fy,int tx,int ty,bool transmit){
  char p=checkers[fy][fx];
  bool jump=abs(tx-fx)==2;
  int capturedX=(fx+tx)/2, capturedY=(fy+ty)/2;
  checkers[ty][tx]=p;
  checkers[fy][fx]='.';
  if(jump)checkers[capturedY][capturedX]='.';
  if((checkerRed(p)&&ty==7)||(!checkerRed(p)&&ty==0))checkers[ty][tx]=checkerRed(p)?'R':'B';
  pickedX=pickedY=-1;
  countCheckers();
  if(!gameDone&&jump&&checkerCaptureAt(tx,ty)){
    pickedX=tx;pickedY=ty;
    result=redTurn?"Red must jump again":"Blue must jump again";
  }else if(!gameDone){redTurn=!redTurn;result="";countCheckers();}
  // Redraw the moved counter, its empty old square, and a captured counter only.
  checkerSquare(fx,fy);
  checkerSquare(tx,ty);
  if(jump)checkerSquare(capturedX,capturedY);
  if(pickedX>=0)checkerSquare(pickedX,pickedY);
  checkersStatus();
  if(transmit)sendMove(fx,fy,tx,ty);
}
void checkerTap(int x,int y){
  // In AI mode the person is Red, so Blue is reserved for the computer.
  if(gameDone||y<112||y>=416||(gameMode==AI_OFF_MODE&&!redTurn))return;
  int bx=(x-8)/38,by=(y-112)/38;if(!inside(bx,by))return;
  if(pickedX<0){char p=checkers[by][bx];if(p!='.'&&checkerRed(p)==redTurn&&(!checkersAnyCapture(redTurn)||checkerCaptureAt(bx,by))){pickedX=bx;pickedY=by;checkerSquare(bx,by);}return;}
  if(checkerMoveOK(pickedX,pickedY,bx,by)){playCheckerMove(pickedX,pickedY,bx,by,true);return;}
  if(pickedX==bx&&pickedY==by&&result.length()==0){checkerSquare(pickedX,pickedY);pickedX=pickedY=-1;}
}
// A simple on-device opponent: it takes a legal capture first, then the first legal move.
// Chess uses Black; Checkers uses Blue. It runs after a short pause so the player's move is visible.
void doChessAiMove(){
  int bestFx=-1,bestFy=-1,bestTx=-1,bestTy=-1,bestScore=-1;
  for(int fy=0;fy<8;fy++)for(int fx=0;fx<8;fx++) if(chess[fy][fx]!='.'&&!isupper((unsigned char)chess[fy][fx]))
    for(int ty=0;ty<8;ty++)for(int tx=0;tx<8;tx++) if(chessLegal(fx,fy,tx,ty)){
      char taken=chess[ty][tx]; int score=taken=='.'?0:1;
      if(tolower((unsigned char)taken)=='q')score=5;
      else if(tolower((unsigned char)taken)=='r')score=4;
      else if(tolower((unsigned char)taken)=='b'||tolower((unsigned char)taken)=='n')score=3;
      if(score>bestScore){bestScore=score;bestFx=fx;bestFy=fy;bestTx=tx;bestTy=ty;}
    }
  if(bestFx>=0)playChessMove(bestFx,bestFy,bestTx,bestTy,false);
}
void doCheckersAiMove(){
  int bestFx=-1,bestFy=-1,bestTx=-1,bestTy=-1; bool mustJump=checkersAnyCapture(false);
  for(int fy=0;fy<8&&bestFx<0;fy++)for(int fx=0;fx<8&&bestFx<0;fx++) if(checkers[fy][fx]!='.'&&!checkerRed(checkers[fy][fx]))
    for(int ty=0;ty<8&&bestFx<0;ty++)for(int tx=0;tx<8;tx++) if(checkerMoveOK(fx,fy,tx,ty)&&(!mustJump||abs(tx-fx)==2)){
      bestFx=fx;bestFy=fy;bestTx=tx;bestTy=ty;
    }
  if(bestFx>=0)playCheckerMove(bestFx,bestFy,bestTx,bestTy,false);
}
void doAiMove(){
  if(gameDone||gameMode!=AI_OFF_MODE)return;
  if(gameType==CHESS_GAME&&!whiteTurn)doChessAiMove();
  if(gameType==CHECKERS_GAME&&!redTurn)doCheckersAiMove();
}

void receiveMove(){
  if(!gamePeer||!gamePeer.available())return;
  // A partial Wi-Fi packet must not make touch wait for the normal stream timeout.
  gamePeer.setTimeout(8);
  String m=gamePeer.readStringUntil('\n');
  m.trim();
  if(gameType==SUDOKU_GAME){int cell,value,map,mistakes,finished;
  if(sscanf(m.c_str(),"S,%d,%d",&cell,&value)==2&&cell>=0&&cell<81&&sudokuAnswer[cell]==value){sudokuBoard[cell]=value;if(page==SUDOKU)drawSudoku();}
  else if(sscanf(m.c_str(),"P,%d,%d,%d",&map,&mistakes,&finished)==3){sudokuMap=(map%3+3)%3;resetSudoku();sudokuMistakes=mistakes;gameDone=finished!=0;result=gameDone?(sudokuMistakes>=3?"You win - other player made 3 mistakes!":"Other player finished first"):"";if(page==SUDOKU)drawSudoku();}
  else if(m=="F"){gameDone=true;result="Other player finished first";if(page==SUDOKU)drawSudoku();addNotification("Other player won Sudoku");}
  else if(m=="L"){gameDone=true;result="You win - other player made 3 mistakes!";if(page==SUDOKU)drawSudoku();addNotification("You won Wi-Fi Sudoku!");}
  else if(m.startsWith("N,")){sudokuMap=(m.substring(2).toInt()%3+3)%3;resetSudoku();gameDone=false;result="";if(page==SUDOKU)drawSudoku();}
  return;}int fx,fy,tx,ty;if(sscanf(m.c_str(),"M,%d,%d,%d,%d",&fx,&fy,&tx,&ty)!=4||!inside(fx,fy)||!inside(tx,ty))return;if(gameType==CHESS_GAME){if(chessLegal(fx,fy,tx,ty))playChessMove(fx,fy,tx,ty,false);}else if(checkerMoveOK(fx,fy,tx,ty))playCheckerMove(fx,fy,tx,ty,false);}

void open(Page p){page=p;  if(p==SETTINGS)drawSettings();else if(p==BROWSER)drawBrowser();else if(p==STORE)drawStore();else if(p==PHOTOS)drawPhotos();else if(p==PIXEL)drawPixelStudio();else if(p==FILES)drawFiles();else if(p==SCREEN_TIME)drawScreenTime();else if(p==DEVICE)drawDevice();else if(p==CALC)drawCalc();else if(p==NOTES)drawNotes();else if(p==NOTIFICATIONS)drawNotifications();else if(p==CLOCKAPP)drawClock();else if(p==WEATHER)drawWeather();else if(p==MESSENGER)Messenger::draw();else if(p==CHESS){gameType=CHESS_GAME;drawChess();}else if(p==CHECKERS){gameType=CHECKERS_GAME;drawCheckers();}else if(p==SUDOKU){gameType=SUDOKU_GAME;drawSudoku();}}
void tap(int x,int y){if(page==MESSENGER){Messenger::tap(x,y);return;}if(page!=HOME&&x<72&&y<55){pixelNaming=false;drawHome();return;}if(page==HOME){
  if(x>=270&&y>=30&&y<70){unreadNotificationCount=0;open(NOTIFICATIONS);return;}
  if(y>=370&&y<397){homeScreen=x<160?0:1;drawHome();return;}
  if(y>=397){if(x<86)open(MESSENGER);else if(x<162)open(BROWSER);else if(x<238)open(NOTES);else open(SETTINGS);return;}
  if(x<12||x>315||y<75||y>365)return;
  int col=(x-17)/77,row=(y-78)/103;if(col<0||col>3||row<0||row>2)return;
  int n=homeScreen*12+row*4+col;if(n>=16)return;
  Page map[]={MESSENGER,BROWSER,STORE,SETTINGS,CHESS,CHECKERS,SUDOKU,CALC,NOTES,PIXEL,FILES,CLOCKAPP,WEATHER,SCREEN_TIME,FILES,DEVICE};open(map[n]);return;}if(page==SETTINGS){  if(y>=190&&y<230){Messenger::openWifiSetup();return;}
  else if(y>=325&&y<365)open(FILES);
  else if(y>=370&&y<410)open(SCREEN_TIME);
  else if(y>=415&&y<470)open(DEVICE);
  return; } if(page==BROWSER){
  if(y>=438&&y<475){
    if(x<52){aiCaps=!aiCaps;drawBrowser();return;}
    if(x<94){aiNumbers=!aiNumbers;drawBrowser();return;}
    if(x<213){aiPrompt+=' ';drawAiPrompt();return;}
    if(x<266){if(aiPrompt.length())aiPrompt.remove(aiPrompt.length()-1);drawAiPrompt();return;}
    aiReply=makeAiReply(aiPrompt);
    aiPrompt="";  // Start each new question with a clean input box.
    drawAiPrompt();
    drawAiReply();
    return;
  }
  if(y>=326&&y<436){
    int row=(y-326)/37;
    const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
    const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
    const char* line=aiNumbers?digits[row]:letters[row];
    int n=strlen(line),gap=1,w=(320-(n-1)*gap)/n,start=(320-(n*(w+gap)-gap))/2,i=(x-start)/(w+gap);
    if(i>=0&&i<n&&x>=start+i*(w+gap)&&x<start+i*(w+gap)+w){char key=line[i];if(!aiNumbers&&!aiCaps)key=tolower((unsigned char)key);aiPrompt+=key;drawAiPrompt();}
    return;
  }
  if(y>=67&&y<109&&x>=252){
    aiReply=makeAiReply(aiPrompt);
    aiPrompt="";  // Clear the completed question so typing can begin immediately.
    drawAiPrompt();
    drawAiReply();
  }
  return;
 }
 if(page==NOTIFICATIONS){
   // Every visible alert comes from Messenger or a phone action. Tapping one
   // takes the user straight to Messenger so a new text from the other screen
   // can be read and answered immediately.
   if(y>=119&&y<431){open(MESSENGER);}
   return;
 }
 if(page==PHOTOS){if(selectedPhoto>=0){if(y>=370&&y<410){selectedPhoto=-1;drawPhotos();}else if(y>=420&&y<458){String path=String("/pixel_art_")+selectedPhoto+".bin";SD.remove(path.c_str());SD.remove((String("/pixel_art_")+selectedPhoto+".txt").c_str());selectedPhoto=-1;addNotification("Pixel art deleted");drawPhotos();}return;}if(y>=405&&y<445){open(PIXEL);return;}if(y>=100&&y<388){int col=x>=165?1:0,row=(y-100)/96,slot=row*2+col;if(slot>=0&&slot<6){uint16_t pixels[1024];uint8_t size=0;if(readPhoto(slot,pixels,size)){selectedPhoto=slot;drawPhotos();}}}return;}
 if(pixelNaming){
   // The naming page deliberately uses the same touch zones as Messenger.
   // Only the small white name field changes while letters are typed.
   if(y>=438&&y<475){
     if(x<52){pixelNameCaps=!pixelNameCaps;drawPixelName();return;}
     if(x<94){pixelNameNumbers=!pixelNameNumbers;drawPixelName();return;}
     if(x<213){pixelName+=' ';}
     else if(x<266){if(pixelName.length())pixelName.remove(pixelName.length()-1);}
     else{
       if(pixelRenameExisting) savePixelName(fileGallerySelected);
       else savePixelArt();
       pixelNaming=false; pixelRenameExisting=false; pixelNameCaps=false; pixelNameNumbers=false; open(FILES); return;
     }
     tft.fillRoundRect(12,66,296,52,12,TFT_WHITE);
     String shown=pixelName.substring(max(0,(int)pixelName.length()-28));
     label(shown,23,84,TFT_BLACK,TFT_WHITE,2);
     return;
   }
   if(y>=328&&y<436){
     int row=(y-328)/35;
     const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
     const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
     const char* line=pixelNameNumbers?digits[row]:letters[row];
     int n=strlen(line),gap=1,w=(320-(n-1)*gap)/n,start=(320-(n*(w+gap)-gap))/2,i=(x-start)/(w+gap);
     if(i>=0&&i<n&&x>=start+i*(w+gap)&&x<start+i*(w+gap)+w){
       char key=line[i];if(!pixelNameNumbers&&!pixelNameCaps)key=tolower((unsigned char)key);
       pixelName+=key;
       tft.fillRoundRect(12,66,296,52,12,TFT_WHITE);
       String shown=pixelName.substring(max(0,(int)pixelName.length()-28));
       label(shown,23,84,TFT_BLACK,TFT_WHITE,2);
     }
   }
   return;
 }
 if(page==PIXEL){
   if(pixelPalette){
     if(y>=92&&y<352){int col=x/20,row=(y-92)/26,i=row*16+col;if(col>=0&&col<16&&row>=0&&row<10){pixelSelected=pixelColor(i);pixelErase=false;pixelEye=false;pixelPalette=false;drawPixelStudio();}return;}
     if(y>=410&&y<452){pixelPalette=false;drawPixelStudio();} return;
   }
   if(y>=65&&y<369&&x>=8&&x<312){
     int px=(x-8)/19,py=(y-65)/19;
     if(px>=0&&px<16&&py>=0&&py<16){
       // The first square starts one undoable stroke; held-finger movement adds
       // nearby squares without redrawing the toolbar or the rest of the page.
       pixelStrokeTo(px,py);
     }
     return;
   }
   if(y>=377&&y<425){
     pixelStrokeActive=false;
     if(x>=48&&x<94){
       if(pixelUndoCount){
         // Undo swaps the visible art into Redo, then restores the most recent
         // saved before-stroke picture.  The history is kept even for a one-pixel tap.
         if(pixelRedoCount >= 7){memmove(pixelRedo[0],pixelRedo[1],sizeof(pixelRedo[0])*6);pixelRedoCount=6;}
         pixelSnapshot(pixelRedo[pixelRedoCount++]);
         pixelUndoCount--;
         pixelRestoreCanvas(pixelUndo[pixelUndoCount]);
         drawPixelUndoControl();drawPixelRedoControl();
       }
     }
     else if(x>=94&&x<140){
       if(pixelRedoCount){
         // Redo performs the opposite swap, so Undo remains available afterwards.
         if(pixelUndoCount >= 7){memmove(pixelUndo[0],pixelUndo[1],sizeof(pixelUndo[0])*6);pixelUndoCount=6;}
         pixelSnapshot(pixelUndo[pixelUndoCount++]);
         pixelRedoCount--;
         pixelRestoreCanvas(pixelRedo[pixelRedoCount]);
         drawPixelUndoControl();drawPixelRedoControl();
       }
     }
     else if(x>=140&&x<181){pixelEye=!pixelEye;drawPixelPickControl();}
     else if(x>=181&&x<231){pixelErase=!pixelErase;drawPixelEraseControl();}
     else if(x>=231&&x<272){pixelPushUndo();pixelFlood(0,0,pixelErase?TFT_BLACK:pixelSelected);drawPixelCanvas();drawPixelUndoControl();drawPixelRedoControl();}
     else if(x>=272){pixelPalette=true;drawPixelStudio();return;}
     return;
   }
   if(y>=434&&y<475){
     if(x<80){pixelNaming=true;pixelRenameExisting=false;pixelNameCaps=false;pixelNameNumbers=false;drawPixelName();}
     else if(x<166){fileGallerySelected=-1;open(FILES);}
     else if(x<224){memset(pixelCanvas,0,sizeof(pixelCanvas));memset(pixelUndo,0,sizeof(pixelUndo));memset(pixelRedo,0,sizeof(pixelRedo));pixelUndoCount=0;pixelRedoCount=0;pixelName="New picture";drawPixelStudio();}
     return;
   }
   return;
 }
 if(page==FILES){
   if(fileGallerySelected>=0){
     if(y>=370&&y<408){
       if(x<106){fileGallerySelected=-1;drawFiles();}
       else if(x<204){
         String path=String("/pixel_art_")+fileGallerySelected+".txt";
         File n=SD.open(path.c_str(),FILE_READ);
         pixelName=n?n.readString():String("Pixel art"); if(n)n.close(); pixelName.trim();
         pixelNaming=true;pixelRenameExisting=true;pixelNameCaps=false;pixelNameNumbers=false;drawPixelName();
       } else {SD.remove((String("/pixel_art_")+fileGallerySelected+".bin").c_str());SD.remove((String("/pixel_art_")+fileGallerySelected+".txt").c_str());addNotification("Pixel art deleted");fileGallerySelected=-1;drawFiles();}
       return;
     }
     if(y>=423&&y<461){memset(pixelCanvas,0,sizeof(pixelCanvas));memset(pixelUndo,0,sizeof(pixelUndo));memset(pixelRedo,0,sizeof(pixelRedo));pixelName="New picture";open(PIXEL);return;}
     return;
   }
   if(y>=392&&y<426){
     if(x<74&&fileGalleryPage>0){fileGalleryPage--;drawFiles();}
     else if(x>=82&&x<238){memset(pixelCanvas,0,sizeof(pixelCanvas));memset(pixelUndo,0,sizeof(pixelUndo));memset(pixelRedo,0,sizeof(pixelRedo));pixelName="New picture";open(PIXEL);}
     else if(x>=246&&fileGalleryPage<((PIXEL_ART_SLOTS-1)/6)){fileGalleryPage++;drawFiles();}
     return;
   }
   if(y>=110&&y<356){int col=x>=165?1:0,row=(y-110)/91,slot=fileGalleryPage*6+row*2+col;uint16_t pixels[1024];uint8_t size=0;if(slot<PIXEL_ART_SLOTS&&readPhoto(slot,pixels,size)){fileGallerySelected=slot;drawFiles();}return;}
   return;
 }
 if(page==WEATHER){if(y>=443&&y<478){refreshWeather();}return;}
 if(page==STORE){if(y>=99&&y<387&&x>=220){int choice=(y-99)/72;if(storeNotice==choice){Page appPage[]={MESSENGER,CHESS,CHECKERS,NOTES};open(appPage[choice]);}else{storeNotice=choice;drawStore();}}return;}
 if(page==SUDOKU){sudokuTap(x,y);return;}
 if(page==CHESS||page==CHECKERS){
   if(y>=426&&y<468){
     // Start the selected game over while keeping the currently selected mode.
     resetGames();
     if(page==CHESS)drawChess();else drawCheckers();
     return;
   }
   if(y>=61&&y<95){
     if(x>=78&&x<156){gameMode=TWO_PLAYER_MODE;if(page==CHESS)drawChess();else drawCheckers();}
     else if(x>=160&&x<236){gameMode=AI_OFF_MODE;aiMoveAt=millis();if(page==CHESS)drawChess();else drawCheckers();}
     else if(x>=240){gameMode=WIFI_MODE;page=GAME_WIFI;drawGameWifi();}
     return;
   }
   if(page==CHESS)chessTap(x,y);else checkerTap(x,y);return;
 }if(page==GAME_WIFI){if(y>=145&&y<202){gameMode=WIFI_MODE;hosting=true;joining=false;gameServer.begin();page=gameType==CHESS_GAME?CHESS:(gameType==CHECKERS_GAME?CHECKERS:SUDOKU);if(page==CHESS)drawChess();else if(page==CHECKERS)drawCheckers();else drawSudoku();}else if(y>=220&&y<277){gameMode=WIFI_MODE;hosting=false;joining=true;retryAt=0;page=gameType==CHESS_GAME?CHESS:(gameType==CHECKERS_GAME?CHECKERS:SUDOKU);if(page==CHESS)drawChess();else if(page==CHECKERS)drawCheckers();else drawSudoku();}else if(y>=295&&y<345)open(MESSENGER);return; }if(page==CALC){
   if(y>=151&&y<436&&x>=15&&x<319){
     int row=(y-151)/57,col=(x-15)/76;
     if(row>=0&&row<5&&col>=0&&col<4){const char* keys[]={"C","+/-","%","/","7","8","9","x","4","5","6","-","1","2","3","+","0",".","=","="};calculatorKey(keys[row*4+col]);}
   }
   return;
 }
 if(page==NOTES){
   if(y>=438&&y<475){
     if(x<52){noteCaps=!noteCaps;drawNoteKeyboard();return;}
     if(x<94){noteNumbers=!noteNumbers;drawNoteKeyboard();return;}
     if(x<213){noteText+=' ';drawNoteInput();return;}
     if(x<266){if(noteText.length())noteText.remove(noteText.length()-1);drawNoteInput();return;}
     if(sdCardReady){
       SD.remove("/notes.txt");
       File f=SD.open("/notes.txt",FILE_WRITE);
       if(f){f.print(noteText);f.close();addNotification("Note saved to microSD");}
       else addNotification("Could not save note to microSD");
     } else addNotification("Insert microSD to save notes");
     return;
   }
   if(y>=328&&y<436){
     int row=(y-328)/35;
     const char* letters[]={"QWERTYUIOP","ASDFGHJKL","ZXCVBNM"};
     const char* digits[]={"1234567890",".-/:;()@#","$&?!'\"+=_"};
     const char* line=noteNumbers?digits[row]:letters[row];
     int n=strlen(line),gap=1,w=(320-(n-1)*gap)/n,start=(320-(n*(w+gap)-gap))/2,i=(x-start)/(w+gap);
     if(i>=0&&i<n&&x>=start+i*(w+gap)&&x<start+i*(w+gap)+w){
       char key=line[i];if(!noteNumbers&&!noteCaps)key=tolower((unsigned char)key);
       noteText+=key;drawNoteInput();
     }
   }
   return;
 }
}

void setup(){
  Serial.begin(115200);
  launchedAt=millis();
  pinMode(TFT_BACKLIGHT_PIN,OUTPUT);
  digitalWrite(TFT_BACKLIGHT_PIN,HIGH);
  tft.init();
  tft.setRotation(0);
  Wire.begin(TOUCH_SDA_PIN,TOUCH_SCL_PIN,400000);
  touch.begin();
  touch.setRotation(1);
  SPI.begin(SD_SCK_PIN,SD_MISO_PIN,SD_MOSI_PIN,SD_CS_PIN);
  sdCardReady=SD.begin(SD_CS_PIN);
  // Earlier firmware filled the ESP32's internal Wi-Fi settings area. Messenger
  // stores its credentials on the microSD card, so clearing this stale area is
  // safe and gives the Wi-Fi driver room to join the network the user selects.
  esp_err_t nvsResult = nvs_flash_erase();
  if (nvsResult == ESP_OK) nvs_flash_init();
  WiFi.persistent(false);
  WiFi.mode(WIFI_STA);
  WiFi.setAutoReconnect(false);
  Messenger::beginAutoConnect();
  beginNetworkTime();
  resetGames();
  drawHome();
}
void loop(){
  touch.read();
  if(!touch.isTouched){
    pixelStrokeActive=false;
    pixelLastX=pixelLastY=-1;
    // Home is tap-only: releasing a finger never changes pages.
    homeSwipeTracking=false;
    if(locked){
      if(!liftedAt)liftedAt=millis();
      else if(millis()-liftedAt>55)locked=false;
    }
  }else{
    liftedAt=0;
    int x=touch.points[0].x,y=touch.points[0].y;
    if(!locked){
      locked=true;
      // Open buttons immediately on touch. The page dots remain the only
      // launcher control for moving between the two app pages.
      if(x>=0&&x<320&&y>=0&&y<480)tap(x,y);
    }else if(page==PIXEL&&!pixelPalette&&!pixelNaming&&x>=8&&x<312&&y>=65&&y<369){
      pixelStrokeTo((x-8)/19,(y-65)/19);
    }
  }
  // Keep the chat connection listening even while Home, Weather, or another app is open.
  // Incoming messages can therefore update the phone-wide notification badge immediately.
  Messenger::tick();
  beginNetworkTime();
  if(page==HOME && millis()/60000!=lastHomeClockDraw){lastHomeClockDraw=millis()/60000;drawHomeClock();}
  if(page==CLOCKAPP&&millis()/1000!=lastClockDraw)refreshClock();
  // Relative times change once per second, but their small text fields are the
  // only part of Notifications repainted. New alerts redraw the list in addNotification().
  if(page==NOTIFICATIONS&&millis()/1000!=lastNotificationDraw) refreshNotificationAges();
  if((page==CHESS||page==CHECKERS)&&gameMode==AI_OFF_MODE&&!gameDone&&millis()-aiMoveAt>450){
    bool aiTurn=(page==CHESS&&!whiteTurn)||(page==CHECKERS&&!redTurn);
    if(aiTurn){aiMoveAt=millis();doAiMove();}
  }
  if((page==CHESS||page==CHECKERS||page==SUDOKU)&&WiFi.status()==WL_CONNECTED){
    if(hosting&&(!gamePeer||!gamePeer.connected())){WiFiClient c=gameServer.available();if(c){gamePeer=c;if(gameType==SUDOKU_GAME)sendSudokuState();}}
    if(joining&&(!gamePeer||!gamePeer.connected())&&millis()-retryAt>3000){
      retryAt=millis();
      IPAddress ip;
      // Do not let a powered-off second screen stall touch while TCP waits.
      if(ip.fromString(savedIp)&&gamePeer.connect(ip,GAME_PORT,80)){if(gameType==SUDOKU_GAME)gamePeer.print("Q\\n");}
    }
    receiveMove();
  }
  // Let Wi-Fi run, while returning to touch and drawing on the next millisecond.
  delay(1);
}