Pixel-Style Mini OS

#include <Arduino.h>
#include <M5Unified.h>
#include <WiFi.h>
#include <HTTPClient.h>
#include <Preferences.h>
#include <lvgl.h>
#include <esp_system.h>
#include <esp_heap_caps.h>


struct VideoInfo { const char *title; const char *channel; uint32_t color; };


// Forward declarations

// Forward declarations

// Forward declarations
static void saveVideoGateway(lv_event_t *);

static void restoreBackground();

static void flushDisplay(lv_display_t *d, const lv_area_t *a, uint8_t *pixels);
static void readTouch(lv_indev_t *, lv_indev_data_t *data);
static void setStatus();
static void styleLabel(lv_obj_t *obj, const lv_font_t *font, lv_color_t color);
static void addCard(const char *heading, const char *detail, int y, int h);
static void clearPage(const char *title, const char *subtitle);
static void navHome(lv_event_t *);
static void navBack(lv_event_t *);
static void navApps(lv_event_t *);
static void makeNav();
static void fieldFocused(lv_event_t *e);
static String fetchText(const char *url);
static void browserFetch(lv_event_t *);
static void createVideoCard(int index, int y);
static void connectWiFi(lv_event_t *);
static void chooseBackground(lv_event_t *e);
static void chooseKeyboard(lv_event_t *e);
static void chooseSaver(lv_event_t *e);
static void restartDevice(lv_event_t *);
static void brightnessChanged(lv_event_t *e);
static void dismissSaver(lv_event_t *);
static void showSaver();
static void checkGestureAndSaver();
static void bootFinished(lv_timer_t *t);
static void showBoot();

static constexpr uint16_t DRAW_W = 720;
static constexpr uint16_t DRAW_LINES = 24;
static constexpr uint32_t IDLE_MS = 60000;
static constexpr int NAV_H = 92;
static constexpr int TOP_ZONE = 70;
static constexpr int SWIPE_DISTANCE = 105;
static const char *DEFAULT_BROWSER_URL = "http://worldtimeapi.org/api/ip";

static lv_color_t drawBuffer[DRAW_W * DRAW_LINES];
static Preferences preferences;
static uint16_t screenW = 720, screenH = 1280;
static lv_display_t *displayDriver;
static lv_obj_t *root, *content, *titleLabel, *subtitleLabel, *statusLabel, *keyboard;
static lv_obj_t *ssidField, *passwordField, *browserField, *videoGatewayField, *messageLabel, *brightnessLabel;
static lv_obj_t *screensaver;
static lv_obj_t *bootOverlay;
static String browserUrl = DEFAULT_BROWSER_URL;
// A gateway you control may provide authorised low-resolution JPEG/MJPEG previews.
// The Tab5 decodes those JPEG frames locally; it does not bypass YouTube's web player.
static String videoGatewayUrl = "";
static String backgroundName = "Obsidian";
static String keyboardStyle = "abc";
static String saverStyle = "Clock";
static lv_color_t backgroundColor = lv_color_hex(0x151218);
static bool latestPressed = false, touchDown = false, controlUsed = false, saverVisible = false;
static int latestX = 0, latestY = 0, startY = 0;
static uint32_t lastTouchMs = 0, lastStatusMs = 0;

static const lv_color_t SURFACE = lv_color_hex(0x211F26);
static const lv_color_t CARD = lv_color_hex(0x2B2930);
static const lv_color_t TEXT = lv_color_hex(0xE8E0EA);
static const lv_color_t MUTED = lv_color_hex(0xCAC4D0);
static const lv_color_t PIXEL_BLUE = lv_color_hex(0xA8C7FA);

static void showHome(lv_event_t *e = nullptr);
static void showBrowser(lv_event_t *e = nullptr);
static void showVideo(lv_event_t *e = nullptr);
static void showSettings(lv_event_t *e = nullptr);
static void showControl(lv_event_t *e = nullptr);
static void showSettingsConnections(lv_event_t *e = nullptr);
static void showSettingsAppearance(lv_event_t *e = nullptr);
static void showSettingsInput(lv_event_t *e = nullptr);
static void showSettingsSystem(lv_event_t *e = nullptr);
static void applyBackground();
static void hideKeyboard();

static void flushDisplay(lv_display_t *d, const lv_area_t *a, uint8_t *pixels) {
  M5.Display.pushImage(a->x1, a->y1, a->x2 - a->x1 + 1, a->y2 - a->y1 + 1,
                       reinterpret_cast<lgfx::rgb565_t *>(pixels));
  lv_display_flush_ready(d);
}

static void readTouch(lv_indev_t *, lv_indev_data_t *data) {
  latestPressed = M5.Touch.getCount() > 0;
  if (latestPressed) {
    const auto &p = M5.Touch.getDetail(0);
    latestX = constrain((int)p.x, 0, (int)screenW - 1);
    latestY = constrain((int)p.y, 0, (int)screenH - 1);
    data->point.x = latestX;
    data->point.y = latestY;
    lastTouchMs = millis();
  }
  data->state = latestPressed ? LV_INDEV_STATE_PRESSED : LV_INDEV_STATE_RELEASED;
}

static void setStatus() {
  if (!statusLabel) return;
  String state = WiFi.status() == WL_CONNECTED ? "● " + WiFi.SSID() : "○ Offline";
  lv_label_set_text(statusLabel, state.c_str());
}

static void styleLabel(lv_obj_t *obj, const lv_font_t *font = nullptr, lv_color_t color = TEXT) {
  lv_obj_set_style_text_color(obj, color, 0);
  if (font) lv_obj_set_style_text_font(obj, font, 0);
}

static lv_obj_t *button(lv_obj_t *parent, const char *text, int x, int y, int w, int h, lv_event_cb_t cb = nullptr, void *data = nullptr) {
  lv_obj_t *b = lv_button_create(parent);
  lv_obj_set_pos(b, x, y); lv_obj_set_size(b, w, h);
  lv_obj_set_style_bg_color(b, CARD, 0); lv_obj_set_style_bg_color(b, PIXEL_BLUE, LV_STATE_PRESSED);
  lv_obj_set_style_radius(b, 26, 0); lv_obj_set_style_border_width(b, 0, 0);
  if (cb) lv_obj_add_event_cb(b, cb, LV_EVENT_CLICKED, data);
  lv_obj_t *l = lv_label_create(b); lv_label_set_text(l, text); styleLabel(l, &lv_font_montserrat_20);
  lv_label_set_long_mode(l, LV_LABEL_LONG_WRAP); lv_obj_set_width(l, w - 22); lv_obj_center(l);
  return b;
}

static void addCard(const char *heading, const char *detail, int y, int h = 116) {
  lv_obj_t *card = lv_obj_create(content);
  lv_obj_set_pos(card, 0, y); lv_obj_set_size(card, screenW - 40, h);
  lv_obj_set_style_bg_color(card, CARD, 0); lv_obj_set_style_border_width(card, 0, 0); lv_obj_set_style_radius(card, 28, 0);
  lv_obj_t *head = lv_label_create(card); lv_label_set_text(head, heading); styleLabel(head, &lv_font_montserrat_20); lv_obj_set_pos(head, 22, 16);
  lv_obj_t *detailLabel = lv_label_create(card); lv_label_set_text(detailLabel, detail); styleLabel(detailLabel, nullptr, MUTED);
  lv_obj_set_width(detailLabel, screenW - 84); lv_label_set_long_mode(detailLabel, LV_LABEL_LONG_WRAP); lv_obj_set_pos(detailLabel, 22, 51);
}

static void clearPage(const char *title, const char *subtitle) {
  hideKeyboard();
  lv_obj_clean(content);
  lv_label_set_text(titleLabel, title); lv_label_set_text(subtitleLabel, subtitle);
  lv_obj_scroll_to_y(content, 0, LV_ANIM_OFF);
}

static void navHome(lv_event_t *) { showHome(); }
static void navBack(lv_event_t *) { showHome(); }
static void navApps(lv_event_t *) { showHome(); }

static lv_obj_t *navButton(lv_obj_t *parent, const char *label, int x, lv_event_cb_t cb) {
  // Use plain text rather than optional symbol-font glyphs: every Tab5 build can show these labels.
  lv_obj_t *b = lv_button_create(parent);
  lv_obj_set_pos(b, x, 14); lv_obj_set_size(b, 180, 62);
  lv_obj_set_style_radius(b, 31, 0);
  lv_obj_set_style_bg_color(b, lv_color_hex(0x34313B), 0);
  lv_obj_set_style_bg_opa(b, LV_OPA_COVER, 0);
  lv_obj_set_style_bg_color(b, PIXEL_BLUE, LV_STATE_PRESSED);
  lv_obj_set_style_border_width(b, 0, 0);
  lv_obj_add_event_cb(b, cb, LV_EVENT_CLICKED, nullptr);
  lv_obj_t *l = lv_label_create(b); lv_label_set_text(l, label); styleLabel(l, &lv_font_montserrat_20); lv_obj_center(l);
  return b;
}
static void makeNav() {
  lv_obj_t *nav = lv_obj_create(root);
  lv_obj_set_size(nav, screenW, NAV_H); lv_obj_set_pos(nav, 0, screenH - NAV_H);
  lv_obj_set_style_bg_color(nav, lv_color_hex(0x1B191F), 0); lv_obj_set_style_bg_opa(nav, LV_OPA_COVER, 0);
  lv_obj_set_style_border_width(nav, 0, 0); lv_obj_set_style_radius(nav, 0, 0);
  navButton(nav, "Back", 30, navBack);
  navButton(nav, "Home", 270, navHome);
  navButton(nav, "Apps", 510, navApps);
}

static void fieldFocused(lv_event_t *e) {
  if (!keyboard) return;
  lv_obj_t *field = (lv_obj_t *)lv_event_get_target(e);
  // Make a tap reliable even when LVGL has not yet applied its normal focus state.
  lv_obj_add_state(field, LV_STATE_FOCUSED);
  lv_keyboard_set_textarea(keyboard, field);
  lv_keyboard_set_mode(keyboard, keyboardStyle == "123" ? LV_KEYBOARD_MODE_NUMBER : LV_KEYBOARD_MODE_TEXT_LOWER);
  lv_obj_remove_flag(keyboard, LV_OBJ_FLAG_HIDDEN);
  // This is an overlay, never a card within the scrollable page.
  lv_obj_move_foreground(keyboard);
  lv_obj_scroll_to_view_recursive(field, LV_ANIM_ON);
}
static void hideKeyboard() {
  if (keyboard) {
    lv_keyboard_set_textarea(keyboard, nullptr);
    lv_obj_add_flag(keyboard, LV_OBJ_FLAG_HIDDEN);
  }
}

static lv_obj_t *textField(const char *hint, int y, bool secret = false) {
  lv_obj_t *field = lv_textarea_create(content);
  lv_obj_set_pos(field, 0, y); lv_obj_set_size(field, screenW - 40, 64);
  lv_textarea_set_one_line(field, true); lv_textarea_set_placeholder_text(field, hint); lv_textarea_set_password_mode(field, secret);
  lv_obj_set_style_bg_color(field, CARD, 0); lv_obj_set_style_text_color(field, TEXT, 0); lv_obj_set_style_border_color(field, PIXEL_BLUE, LV_STATE_FOCUSED); lv_obj_set_style_radius(field, 18, 0);
  // Some touch controllers report a click before a focus transition, so accept both.
  lv_obj_add_event_cb(field, fieldFocused, LV_EVENT_FOCUSED, nullptr);
  lv_obj_add_event_cb(field, fieldFocused, LV_EVENT_CLICKED, nullptr);
  return field;
}

static String fetchText(const char *url) {
  if (WiFi.status() != WL_CONNECTED) return "Not connected. Open Settings, then Connections, and join Wi-Fi first.";
  HTTPClient http; http.setTimeout(7000);
  if (!http.begin(url)) return "Could not open that address.";
  int code = http.GET(); String result = code > 0 ? http.getString() : "The network request failed."; http.end();
  result.replace("\n", " "); if (result.length() > 850) result = result.substring(0, 850) + "…";
  return "HTTP " + String(code) + "\n" + result;
}

static void browserFetch(lv_event_t *) {
  String value = lv_textarea_get_text(browserField); value.trim();
  if (!value.startsWith("http://") && !value.startsWith("https://")) { lv_label_set_text(messageLabel, "Use a full address starting with http:// or https://."); return; }
  browserUrl = value; preferences.begin("pixel-desk", false); preferences.putString("browser-url", browserUrl); preferences.end();
  hideKeyboard(); lv_label_set_text(messageLabel, "Fetching readable page data…"); lv_timer_handler();
  String answer = fetchText(browserUrl.c_str()); lv_label_set_text(messageLabel, answer.c_str());
}

static void showHome(lv_event_t *) {
  clearPage("Pixel Desk", "Portrait launcher • swipe down from the top for quick controls.");
  button(content, "Web Browser", 0, 0, (screenW - 60) / 2, 150, showBrowser);
  button(content, "YouTube\nLow data", (screenW - 40) / 2, 0, (screenW - 60) / 2, 150, showVideo);
  button(content, "Settings", 0, 168, (screenW - 60) / 2, 150, showSettings);
  addCard("Quick controls", "Swipe down from the very top edge for brightness, network, and screen-saver controls.", 340, 132);
  addCard("Phone-style navigation", "The round bottom buttons give you Back, Home, and Apps.", 490, 104);
}

static void showBrowser(lv_event_t *) {
  clearPage("Web Browser", "Fetches readable web data; it is not a full HTML page renderer.");
  browserField = textField("https://example.com/data", 0); lv_textarea_set_text(browserField, browserUrl.c_str());
  button(content, "Save URL and fetch page", 0, 82, screenW - 40, 72, browserFetch);
  messageLabel = lv_label_create(content); lv_obj_set_pos(messageLabel, 4, 180); lv_obj_set_width(messageLabel, screenW - 48); lv_label_set_long_mode(messageLabel, LV_LABEL_LONG_WRAP); styleLabel(messageLabel, nullptr, TEXT);
  lv_label_set_text(messageLabel, "Tap the address box to type. The saved address remains after a restart.");
}


static const VideoInfo videos[] = {
  {"Daily science in 60 seconds", "Open learning feed", 0x3D6E70},
  {"Tiny desk studio session", "Public music channel", 0x74558D},
  {"How touch screens work", "Tech explainer", 0x8B5A48}
};
static int selectedVideo = 0;
static void videoOptions(lv_event_t *e);
static void showMiniPlayer(lv_event_t *);
static void loadGatewayFrame(lv_event_t *);
static void setVideoBackground(lv_event_t *);
static void watchVideo(lv_event_t *);

static void createVideoCard(int index, int y) {
  lv_obj_t *b = button(content, videos[index].title, 0, y, screenW - 40, 142, nullptr);
  lv_obj_set_style_bg_color(b, lv_color_hex(videos[index].color), 0);
  lv_obj_add_event_cb(b, videoOptions, LV_EVENT_LONG_PRESSED, (void *)(intptr_t)index);
  lv_obj_add_event_cb(b, showMiniPlayer, LV_EVENT_CLICKED, (void *)(intptr_t)index);
  lv_obj_t *small = lv_label_create(b); lv_label_set_text(small, videos[index].channel); styleLabel(small, nullptr, TEXT); lv_obj_set_pos(small, 18, 102);
}
static void saveVideoGateway(lv_event_t *) {
  videoGatewayUrl = lv_textarea_get_text(videoGatewayField); videoGatewayUrl.trim();
  preferences.begin("pixel-desk", false); preferences.putString("video-gateway", videoGatewayUrl); preferences.end();
  hideKeyboard();
}
static void showVideo(lv_event_t *) {
  clearPage("YouTube • low data", "Tap a video for its mini player. Press and hold for more options.");
  videoGatewayField = textField("https://your-gateway.example/frame.jpg", 0);
  lv_textarea_set_text(videoGatewayField, videoGatewayUrl.c_str());
  button(content, "Save permitted JPEG stream", 0, 76, screenW - 40, 58, saveVideoGateway);
  for (int i = 0; i < 3; ++i) createVideoCard(i, 150 + i * 158);
  addCard("Video decoding", "The Tab5 decodes JPEG preview frames from the saved permitted gateway. Direct YouTube web streams are not supported.", 630, 148);
}
static void videoOptions(lv_event_t *e) {
  selectedVideo = (int)(intptr_t)lv_event_get_user_data(e);
  clearPage("Video options", videos[selectedVideo].title);
  button(content, "Set thumbnail colour\nas background", 0, 0, screenW - 40, 100, setVideoBackground);
  button(content, "Watch in mini player", 0, 118, screenW - 40, 100, showMiniPlayer);
  button(content, "Watch", 0, 236, screenW - 40, 100, watchVideo);
}
static void setVideoBackground(lv_event_t *) {
  backgroundName = String("Video colour ") + String(selectedVideo + 1);
  backgroundColor = lv_color_hex(videos[selectedVideo].color);
  preferences.begin("pixel-desk", false); preferences.putString("background", backgroundName); preferences.end(); applyBackground(); showHome();
}
static void loadGatewayFrame(lv_event_t *e) {
  if (!messageLabel) return;
  if (!videoGatewayUrl.startsWith("http://") && !videoGatewayUrl.startsWith("https://")) { lv_label_set_text(messageLabel, "Save a full http:// or https:// JPEG-frame address first."); return; }
  if (WiFi.status() != WL_CONNECTED) { lv_label_set_text(messageLabel, "Connect to Wi-Fi before loading the preview."); return; }
  lv_label_set_text(messageLabel, "Downloading and decoding JPEG frame…");
  HTTPClient http; http.setTimeout(10000);
  if (!http.begin(videoGatewayUrl)) { lv_label_set_text(messageLabel, "Could not open the video gateway."); return; }
  int status = http.GET(); int bytes = http.getSize();
  if (status != HTTP_CODE_OK || bytes <= 0 || bytes > 450000) { http.end(); lv_label_set_text(messageLabel, "Gateway must return one JPEG image under 450 KB."); return; }
  uint8_t *jpg = (uint8_t *)heap_caps_malloc(bytes, MALLOC_CAP_SPIRAM | MALLOC_CAP_8BIT);
  if (!jpg) { http.end(); lv_label_set_text(messageLabel, "Not enough memory for this preview frame."); return; }
  WiFiClient *stream = http.getStreamPtr(); size_t received = stream->readBytes(jpg, bytes); http.end();
  if (received != (size_t)bytes) { free(jpg); lv_label_set_text(messageLabel, "The preview frame download was incomplete."); return; }
  // M5GFX performs the JPEG decode on the Tab5 and draws the resulting image locally.
  M5.Display.drawJpg(jpg, received, 10, 190, screenW - 20, 300);
  free(jpg); lv_label_set_text(messageLabel, "Decoded JPEG preview. Tap Load preview to refresh it.");
}
static void showMiniPlayer(lv_event_t *e) {
  if (e && lv_event_get_user_data(e)) selectedVideo = (int)(intptr_t)lv_event_get_user_data(e);
  clearPage("Mini player", videos[selectedVideo].title);
  lv_obj_t *art = lv_obj_create(content); lv_obj_set_pos(art, 0, 0); lv_obj_set_size(art, screenW - 40, 330); lv_obj_set_style_bg_color(art, lv_color_hex(videos[selectedVideo].color), 0); lv_obj_set_style_radius(art, 30, 0); lv_obj_set_style_border_width(art, 0, 0);
  lv_obj_t *note = lv_label_create(art);
  String decoderText = videoGatewayUrl.length() ? "JPEG decoder ready\nOpen stream in Browser" : "Add a permitted JPEG\nstream in the YouTube app";
  lv_label_set_text(note, decoderText.c_str()); styleLabel(note, &lv_font_montserrat_20); lv_obj_center(note);
  button(content, "Load preview frame", 0, 345, screenW - 40, 64, loadGatewayFrame);
  messageLabel = lv_label_create(content); lv_obj_set_pos(messageLabel, 4, 425); lv_obj_set_width(messageLabel, screenW - 48); lv_label_set_long_mode(messageLabel, LV_LABEL_LONG_WRAP); styleLabel(messageLabel, nullptr, TEXT);
  lv_label_set_text(messageLabel, "This is a real JPEG decoder for one authorised gateway frame. Direct YouTube web-player streams are not supported.");
}
static void watchVideo(lv_event_t *) { showMiniPlayer(nullptr); }

static void connectWiFi(lv_event_t *) {
  const char *ssid = lv_textarea_get_text(ssidField); const char *pass = lv_textarea_get_text(passwordField);
  if (!strlen(ssid)) { lv_label_set_text(messageLabel, "Enter your Wi-Fi name first."); return; }
  preferences.begin("pixel-desk", false); preferences.putString("ssid", ssid); preferences.putString("password", pass); preferences.end();
  hideKeyboard(); lv_label_set_text(messageLabel, "Connecting… this can take a few seconds."); WiFi.disconnect(); WiFi.begin(ssid, pass);
}

static void showSettings(lv_event_t *) {
  clearPage("Settings", "Choose a category.");
  button(content, "Connections", 0, 0, screenW - 40, 94, showSettingsConnections);
  button(content, "Appearance", 0, 112, screenW - 40, 94, showSettingsAppearance);
  button(content, "Keyboard and screen saver", 0, 224, screenW - 40, 94, showSettingsInput);
  button(content, "System", 0, 336, screenW - 40, 94, showSettingsSystem);
}
static void showSettingsConnections(lv_event_t *) {
  clearPage("Connections", "Wi-Fi details are saved on this Tab5.");
  preferences.begin("pixel-desk", true); String ssid = preferences.getString("ssid", ""); String pass = preferences.getString("password", ""); preferences.end();
  ssidField = textField("Wi-Fi name", 0); passwordField = textField("Wi-Fi password", 78, true); lv_textarea_set_text(ssidField, ssid.c_str()); lv_textarea_set_text(passwordField, pass.c_str());
  button(content, "Save and connect", 0, 158, screenW - 40, 72, connectWiFi);
  messageLabel = lv_label_create(content); lv_obj_set_pos(messageLabel, 4, 250); lv_obj_set_width(messageLabel, screenW - 48); styleLabel(messageLabel, nullptr, TEXT);
  String state = WiFi.status() == WL_CONNECTED ? "Connected to " + WiFi.SSID() : "Not connected"; lv_label_set_text(messageLabel, state.c_str());
  addCard("Bluetooth", "Bluetooth controls are not available through the Tab5 Arduino wireless link. Wi-Fi is available here.", 310, 128);
}
static void chooseBackground(lv_event_t *e) {
  int value = (int)(intptr_t)lv_event_get_user_data(e);
  if (value == 0) { backgroundName = "Obsidian"; backgroundColor = lv_color_hex(0x151218); }
  if (value == 1) { backgroundName = "Violet"; backgroundColor = lv_color_hex(0x302B45); }
  if (value == 2) { backgroundName = "Forest"; backgroundColor = lv_color_hex(0x203A35); }
  preferences.begin("pixel-desk", false); preferences.putString("background", backgroundName); preferences.end(); applyBackground(); showSettingsAppearance();
}
static void showSettingsAppearance(lv_event_t *) {
  clearPage("Appearance", "Choose a background colour for your phone-style home screen.");
  button(content, "Obsidian", 0, 0, screenW - 40, 82, chooseBackground, (void *)0);
  button(content, "Violet", 0, 100, screenW - 40, 82, chooseBackground, (void *)1);
  button(content, "Forest", 0, 200, screenW - 40, 82, chooseBackground, (void *)2);
  addCard("Current background", backgroundName.c_str(), 310, 104);
}
static void chooseKeyboard(lv_event_t *e) { keyboardStyle = (int)(intptr_t)lv_event_get_user_data(e) ? "123" : "abc"; preferences.begin("pixel-desk", false); preferences.putString("keyboard", keyboardStyle); preferences.end(); showSettingsInput(); }
static void chooseSaver(lv_event_t *e) { int choice = (int)(intptr_t)lv_event_get_user_data(e); saverStyle = choice == 0 ? "Off" : choice == 1 ? "Clock" : "Colour pulse"; preferences.begin("pixel-desk", false); preferences.putString("saver", saverStyle); preferences.end(); showSettingsInput(); }
static void showSettingsInput(lv_event_t *) {
  clearPage("Keyboard and screen saver", "Every text box opens this keyboard when you tap it.");
  button(content, "Letters keyboard", 0, 0, (screenW - 60) / 2, 82, chooseKeyboard, (void *)0);
  button(content, "Number keyboard", (screenW - 40) / 2, 0, (screenW - 60) / 2, 82, chooseKeyboard, (void *)1);
  addCard("Keyboard now", keyboardStyle == "123" ? "Number keyboard" : "Letters keyboard", 105, 94);
  button(content, "Screen saver: off", 0, 220, screenW - 40, 70, chooseSaver, (void *)0);
  button(content, "Screen saver: clock", 0, 304, screenW - 40, 70, chooseSaver, (void *)1);
  button(content, "Screen saver: colour pulse", 0, 388, screenW - 40, 70, chooseSaver, (void *)2);
  addCard("Screen saver now", saverStyle.c_str(), 480, 94);
}
static void restartDevice(lv_event_t *) { lv_label_set_text(messageLabel, "Restarting the Tab5…"); delay(300); esp_restart(); }
static void showSettingsSystem(lv_event_t *) {
  clearPage("System", "System tools for this Tab5.");
  button(content, "Restart Tab5", 0, 0, screenW - 40, 82, restartDevice);
  messageLabel = lv_label_create(content); lv_obj_set_pos(messageLabel, 4, 110); styleLabel(messageLabel, nullptr, MUTED); lv_label_set_text(messageLabel, "Restart closes apps and reloads your saved Wi-Fi, background, keyboard, and screen saver choices."); lv_obj_set_width(messageLabel, screenW - 48); lv_label_set_long_mode(messageLabel, LV_LABEL_LONG_WRAP);
}

static void brightnessChanged(lv_event_t *e) { int val = lv_slider_get_value((lv_obj_t *)lv_event_get_target(e)); M5.Display.setBrightness(val); String s = "Brightness " + String(val) + "%"; lv_label_set_text(brightnessLabel, s.c_str()); }
static void showControl(lv_event_t *) {
  clearPage("Control centre", "Swipe down from the top edge to open this page.");
  brightnessLabel = lv_label_create(content); lv_obj_set_pos(brightnessLabel, 2, 0); styleLabel(brightnessLabel, &lv_font_montserrat_20); lv_label_set_text(brightnessLabel, "Brightness 75%");
  lv_obj_t *slider = lv_slider_create(content); lv_obj_set_pos(slider, 0, 50); lv_obj_set_width(slider, screenW - 40); lv_slider_set_range(slider, 20, 100); lv_slider_set_value(slider, 75, LV_ANIM_OFF); lv_obj_add_event_cb(slider, brightnessChanged, LV_EVENT_VALUE_CHANGED, nullptr);
  addCard("Network", WiFi.status() == WL_CONNECTED ? "Wi-Fi connected" : "Wi-Fi offline — open Settings > Connections.", 100);
  addCard("Screen saver", saverStyle.c_str(), 232);
}

static void applyBackground() { if (root) lv_obj_set_style_bg_color(root, backgroundColor, 0); }
static void restoreBackground() {
  if (backgroundName == "Violet") backgroundColor = lv_color_hex(0x302B45);
  else if (backgroundName == "Forest") backgroundColor = lv_color_hex(0x203A35);
  else if (backgroundName == "Video colour 1") backgroundColor = lv_color_hex(videos[0].color);
  else if (backgroundName == "Video colour 2") backgroundColor = lv_color_hex(videos[1].color);
  else if (backgroundName == "Video colour 3") backgroundColor = lv_color_hex(videos[2].color);
  else { backgroundName = "Obsidian"; backgroundColor = lv_color_hex(0x151218); }
}
static void dismissSaver(lv_event_t *) { if (screensaver) { lv_obj_add_flag(screensaver, LV_OBJ_FLAG_HIDDEN); saverVisible = false; lastTouchMs = millis(); } }
static void showSaver() {
  if (saverStyle == "Off" || saverVisible || !screensaver) return;
  lv_obj_clean(screensaver); lv_obj_set_style_bg_color(screensaver, saverStyle == "Colour pulse" ? lv_color_hex(0x3D526B) : lv_color_hex(0x08070A), 0);
  lv_obj_remove_flag(screensaver, LV_OBJ_FLAG_HIDDEN); saverVisible = true;
  lv_obj_t *l = lv_label_create(screensaver); String s;
  if (saverStyle == "Clock") { unsigned long seconds = millis() / 1000UL; s = String("Pixel Desk\n") + String((seconds / 3600UL) % 24UL) + ":" + String((seconds / 60UL) % 60UL); }
  else s = "Pixel Desk\nTouch to wake";
  lv_label_set_text(l, s.c_str()); styleLabel(l, &lv_font_montserrat_32); lv_obj_center(l);
  if (saverStyle == "Colour pulse") { lv_anim_t pulse; lv_anim_init(&pulse); lv_anim_set_var(&pulse, screensaver); lv_anim_set_values(&pulse, 80, 255); lv_anim_set_duration(&pulse, 1300); lv_anim_set_playback_duration(&pulse, 1300); lv_anim_set_repeat_count(&pulse, LV_ANIM_REPEAT_INFINITE); lv_anim_set_exec_cb(&pulse, [](void *obj, int32_t value) { lv_obj_set_style_bg_opa((lv_obj_t *)obj, (lv_opa_t)value, 0); }); lv_anim_start(&pulse); }
}
static void checkGestureAndSaver() {
  if (latestPressed && saverVisible) { dismissSaver(nullptr); return; }
  if (!latestPressed) { touchDown = false; controlUsed = false; }
  else if (!touchDown) { touchDown = true; startY = latestY; }
  else if (!controlUsed && startY <= TOP_ZONE && latestY - startY >= SWIPE_DISTANCE) { controlUsed = true; showControl(); }
  if (!latestPressed && !saverVisible && millis() - lastTouchMs > IDLE_MS) showSaver();
}
static void bootFinished(lv_timer_t *t) {
  lv_timer_delete(t);
  if (bootOverlay) {
    lv_obj_delete(bootOverlay);
    bootOverlay = nullptr;
  }
  showHome();
}
static void showBoot() {
  // Keep the permanent UI objects alive; this panel sits above them briefly.
  bootOverlay = lv_obj_create(root);
  lv_obj_set_size(bootOverlay, screenW, screenH);
  lv_obj_set_pos(bootOverlay, 0, 0);
  lv_obj_set_style_bg_color(bootOverlay, backgroundColor, 0);
  lv_obj_set_style_border_width(bootOverlay, 0, 0);
  lv_obj_set_style_radius(bootOverlay, 0, 0);
  lv_obj_move_foreground(bootOverlay);
  lv_obj_t *logo = lv_label_create(bootOverlay);
  lv_label_set_text(logo, "Pixel Desk");
  styleLabel(logo, &lv_font_montserrat_32, PIXEL_BLUE);
  lv_obj_align(logo, LV_ALIGN_CENTER, 0, -40);
  lv_obj_t *bar = lv_bar_create(bootOverlay);
  lv_obj_set_size(bar, 330, 16);
  lv_obj_align(bar, LV_ALIGN_CENTER, 0, 35);
  lv_bar_set_range(bar, 0, 100);
  lv_bar_set_value(bar, 100, LV_ANIM_ON);
  lv_timer_create(bootFinished, 950, nullptr);
}

void setup() {
  // ST7123 Tab5 panels can retain state after a USB/warm reset.  Let the integrated
  // touch-and-display controller settle before M5GFX probes its DSI panel ID.
  delay(1200);
  auto cfg = M5.config(); M5.begin(cfg);
  // Rotation 0 is the Tab5's upright portrait panel orientation; M5Unified maps GT911 to this same surface.
  M5.Display.setRotation(0); screenW = M5.Display.width(); screenH = M5.Display.height(); M5.Display.setBrightness(75);
  Serial.begin(115200); Serial.printf("Tab5 portrait: %u x %u; touch %s\n", screenW, screenH, M5.Touch.isEnabled() ? "enabled" : "disabled");
  preferences.begin("pixel-desk", true); String ssid = preferences.getString("ssid", ""); String pass = preferences.getString("password", ""); browserUrl = preferences.getString("browser-url", DEFAULT_BROWSER_URL); videoGatewayUrl = preferences.getString("video-gateway", ""); backgroundName = preferences.getString("background", "Obsidian"); keyboardStyle = preferences.getString("keyboard", "abc"); saverStyle = preferences.getString("saver", "Clock"); preferences.end();
  restoreBackground();
  if (ssid.length()) WiFi.begin(ssid.c_str(), pass.c_str());
  lv_init(); lv_tick_set_cb([]() -> uint32_t { return millis(); });
  displayDriver = lv_display_create(screenW, screenH); lv_display_set_color_format(displayDriver, LV_COLOR_FORMAT_RGB565); lv_display_set_buffers(displayDriver, drawBuffer, nullptr, sizeof(drawBuffer), LV_DISPLAY_RENDER_MODE_PARTIAL); lv_display_set_flush_cb(displayDriver, flushDisplay);
  lv_indev_t *touch = lv_indev_create(); lv_indev_set_type(touch, LV_INDEV_TYPE_POINTER); lv_indev_set_display(touch, displayDriver); lv_indev_set_read_cb(touch, readTouch);
  root = lv_screen_active(); applyBackground();
  titleLabel = lv_label_create(root); lv_obj_set_pos(titleLabel, 22, 38); styleLabel(titleLabel, &lv_font_montserrat_32);
  subtitleLabel = lv_label_create(root); lv_obj_set_pos(subtitleLabel, 24, 84); lv_obj_set_width(subtitleLabel, screenW - 48); lv_label_set_long_mode(subtitleLabel, LV_LABEL_LONG_WRAP); styleLabel(subtitleLabel, nullptr, MUTED);
  statusLabel = lv_label_create(root); lv_obj_set_pos(statusLabel, 24, 120); styleLabel(statusLabel, nullptr, PIXEL_BLUE);
  content = lv_obj_create(root); lv_obj_set_pos(content, 20, 160); lv_obj_set_size(content, screenW - 20, screenH - 160 - NAV_H); lv_obj_set_style_bg_opa(content, LV_OPA_TRANSP, 0); lv_obj_set_style_border_width(content, 0, 0); lv_obj_set_style_pad_all(content, 0, 0);
  // Put the keyboard on LVGL's top layer so pages, navigation, and cards can never cover it.
  keyboard = lv_keyboard_create(lv_layer_top());
  lv_obj_set_size(keyboard, screenW, 370);
  lv_obj_set_pos(keyboard, 0, screenH - 370);
  lv_obj_set_style_bg_color(keyboard, lv_color_hex(0x1B191F), 0);
  lv_obj_set_style_bg_opa(keyboard, LV_OPA_COVER, 0);
  lv_obj_add_event_cb(keyboard, [](lv_event_t *event) {
    lv_event_code_t code = lv_event_get_code(event);
    if (code == LV_EVENT_READY || code == LV_EVENT_CANCEL) hideKeyboard();
  }, LV_EVENT_ALL, nullptr);
  lv_obj_add_flag(keyboard, LV_OBJ_FLAG_HIDDEN);
  makeNav();
  screensaver = lv_obj_create(root); lv_obj_set_size(screensaver, screenW, screenH); lv_obj_set_pos(screensaver, 0, 0); lv_obj_set_style_border_width(screensaver, 0, 0); lv_obj_add_flag(screensaver, LV_OBJ_FLAG_HIDDEN); lv_obj_add_event_cb(screensaver, dismissSaver, LV_EVENT_CLICKED, nullptr);
  lastTouchMs = millis(); setStatus(); showBoot();
}
void loop() {
  M5.update(); lv_timer_handler(); checkGestureAndSaver();
  // USB serial control is available for diagnostics on Windows; it is not Android ADB.
  if (Serial.available()) {
    String command = Serial.readStringUntil('\n'); command.trim(); command.toUpperCase();
    if (command == "HOME") showHome();
    else if (command == "SETTINGS") showSettings();
    else if (command == "CONTROL") showControl();
    else if (command == "RESTART") esp_restart();
    else Serial.println("Commands: HOME, SETTINGS, CONTROL, RESTART");
  }
  if (millis() - lastStatusMs > 1000) { setStatus(); lastStatusMs = millis(); }
  delay(5);
}