Wi-Fi Motion Alarm

// Motion Alarm (Wi-Fi) for the Arduino UNO R4 WiFi.// Same alarm as MotionAlarm (R3), plus a phone app served over the home Wi-Fi// and alerts through the free ntfy app.//// Wiring (same holes as the R3 version, except the buzzer)://   Motion sensor (3 female-to-male wires): GND -> pin 4, OUT -> pin 3, VCC -> pin 2//     (if VCC and GND are the other way round, the program notices and swaps them)//   Keypad (8 male-to-male wires), its holes left to right with the keys facing up://     12, 11, 10, 9, 8, 7, 6, 5//   Buzzer: through the ULN2003 driver board from the starter kit, because R4//     pins only give 8 mA (R3: 20 mA). Driver "+" -> 5V, "-" -> GND,//     IN1 -> A0, IN4 -> A3. The buzzer's two pins go in the two END holes of the//     driver's white socket, either way round: one end hole is the + supply and//     the other is OUT1 or OUT4 (depending on the board), and A0 and A3 are//     driven together, so either one works.//   Light: the built-in "L" light (pin 13), and icons on the 12x8 LED matrix.//// How it works (same as the R3 version)://   OFF -> type the code -> ARMING (15 s to leave) -> ARMED -> movement ->//   COUNTDOWN (15 s to type the code) -> ALARM (siren until the code).//   The code works on the keypad and in the phone app.//   Change the code: while OFF, press *, new code, #, new code again, #.//// Wi-Fi://   The first time (or after pressing # five times while OFF), it makes its own//   network "Motion-Alarm-Setup". Join it with the phone and open//   http://192.168.4.1 to pick the home Wi-Fi and type its password. The//   password stays on the board (EEPROM) - it never goes anywhere else.//   Once on the home Wi-Fi, the app is at http://<its address>/, and ntfy gets//   an "Alarm is online" message with the link. Phone alerts are sent to//   ntfy.sh on a random topic made the first time it starts (shown in the app)://   armed, turned off (and by what), motion detected (the moment the countdown//   starts), and the siren going off (loudest). The motion alert goes out before//   the 15 s countdown starts, so sending it doesn't eat into that time. Other//   alerts wait until nobody is using the keypad (sending takes a second or two).//// Serial: "?" status, "i" Wi-Fi info, "t" test siren, "m" mute, "k" show keys,//   "d" turn off, "r" reset the code to the default, "w" Wi-Fi setup mode.#include <WiFiS3.h>#include <EEPROM.h>#include "FspTimer.h"#include "Arduino_LED_Matrix.h"#include "web_pages.h"#include "icon.h"const int PIR_PIN = 3;int pirVcc = 2;            // pins 2 and 4 trade places if the sensor'sint pirGnd = 4;            // power wires turn out to be the other way roundconst int BUZ_A = A0;      // to the driver's IN1const int BUZ_A2 = A3;     // to the driver's IN4, driven the same as BUZ_Aconst int BUZ_B = -1;      // opposite-phase output for a push-pull driver, or -1const int LIGHT = 13;const int ROW_PINS[4] = {12, 11, 10, 9};const int COL_PINS[4] = {8, 7, 6, 5};const char KEYS[4][4] = {  {'1', '2', '3', 'A'},  {'4', '5', '6', 'B'},  {'7', '8', '9', 'C'},  {'*', '0', '#', 'D'},};const unsigned long WARMUP_MS = 60000UL;const unsigned long EXIT_MS = 15000UL;     // time to walk away after armingconst unsigned long ENTRY_MS = 15000UL;    // time to type the code after movementconst unsigned long DEAF_MS = 5000UL;      // ignore the sensor this long after a soundconst unsigned long CHANGE_TIMEOUT_MS = 30000UL;const unsigned int WAIL_LOW = 1800;const unsigned int WAIL_HIGH = 3000;const unsigned long WAIL_MS = 1000UL;      // one up-and-down sweepconst byte MAX_CODE = 8;const char DEFAULT_CODE[] = "1234";const char SETUP_SSID[] = "Motion-Alarm-Setup";// EEPROM layoutconst int EE_MUTE = 0;const int EE_STATE = 1;const int EE_CODE_MAGIC = 2;const int EE_CODE_LEN = 3;const int EE_CODE = 4;           // up to 8 bytesconst int EE_WIFI_MAGIC = 16;const int EE_SSID = 17;          // 33 bytesconst int EE_PASS = 50;          // 65 bytesconst int EE_TOPIC_MAGIC = 120;const int EE_TOPIC = 121;        // 17 bytesconst int EE_FORCE_SETUP = 140;const byte MUTE_MAGIC = 0xA5;const byte CODE_MAGIC = 0x5C;const byte WIFI_MAGIC = 0x57;const byte TOPIC_MAGIC = 0x7A;const byte FORCE_MAGIC = 0x3C;enum State : byte { DISARMED = 0, ARMED = 1, ALARM = 2, ARMING = 3, ENTRY = 4 };State state = DISARMED;struct Note { bool used; byte prio; char title[32]; char body[80]; char tags[24]; };   // a waiting phone alertbool muted;bool sounding = false;bool echoKeys = false;unsigned long stateStart = 0;unsigned long deafUntil = 0;unsigned long testUntil = 0;unsigned long motionCount = 0;unsigned long warmStart = 0;bool powerConfirmed = false; // the sensor has shown it's powered the right way roundbyte swaps = 0;unsigned long lastPowerCheck = 0;char code[MAX_CODE];byte codeLen;char typed[MAX_CODE];        // the last keys typed (rolling)byte typedLen = 0;byte changeStep = 0;         // 0 = not changing, 1 = first entry, 2 = confirmchar newCode[MAX_CODE];byte newLen = 0;char firstCode[MAX_CODE];byte firstLen = 0;unsigned long lastKeyAt = 0;byte hashCount = 0;          // # presses in a row while OFF (5 = Wi-Fi setup)// ---------- History (shown in the app) ----------struct Event { unsigned long ms; char m[40]; };const int MAX_EVENTS = 10;Event events[MAX_EVENTS];int eventCount = 0;void addEvent(const char *m) {  memmove(&events[1], &events[0], sizeof(Event) * (MAX_EVENTS - 1));  events[0].ms = millis();  strncpy(events[0].m, m, sizeof(events[0].m) - 1);  events[0].m[sizeof(events[0].m) - 1] = 0;  if (eventCount < MAX_EVENTS) eventCount++;  Serial.print(F("Event: "));  Serial.println(m);}// ---------- LED matrix icons ----------ArduinoLEDMatrix matrix;const char *const ICON_OFF[8] = {  "............", "....####....", "...#....#...", "...#....#...",  "...#....#...", "...#....#...", "....####....", "............"};const char *const ICON_ARMED[8] = {  "....####....", "...#....#...", "...#....#...", "..########..",  "..########..", "..###..###..", "..########..", "..########.."};const char *const ICON_ARMING[8] = {  "....####....", "...#....#...", "........#...", "..########..",  "..########..", "..###..###..", "..########..", "..########.."};const char *const ICON_COUNT[8] = {  "..########..", "...#....#...", "....#..#....", ".....##.....",  ".....##.....", "....#..#....", "...#.##.#...", "..########.."};const char *const ICON_ALARM[8] = {  ".....##.....", ".....##.....", ".....##.....", ".....##.....",  ".....##.....", "............", ".....##.....", ".....##....."};const char *const ICON_WIFI[8] = {  "............", "...######...", "..#......#..", ".#..####..#.",  "...#....#...", ".....##.....", ".....##.....", "............"};const char *const ICON_BLANK[8] = {  "............", "............", "............", "............",  "............", "............", "............", "............"};void showIcon(const char *const rows[8]) {  static const char *const *shown = nullptr;  if (rows == shown) return;  shown = rows;  static uint8_t buf[8][12];  for (int r = 0; r < 8; r++)    for (int c = 0; c < 12; c++) buf[r][c] = rows[r][c] == '#';  matrix.renderBitmap(buf, 8, 12);}// ---------- Sound: a timer flips the buzzer output ----------// The pitch is changed with set_period(), which takes effect at the next tick.// (set_frequency() closes and reopens the timer every time, which made the// sweep grind.) The wail itself runs inside the timer interrupt: every 2.5 ms of// sound it steps to the next pitch, so it stays smooth even while the main// program is busy for a second or two sending a phone alert.//// Each tick flips the output, and the timer's next period is set to the length// of the phase after the one starting now (the period register is buffered).// dutyPm is how much of each wave the buzzer is pushed (per thousand): less// than 500 pushes it more gently, which can stop a buzzer rattling.FspTimer sirenTimer;volatile bool buzLevel = false;bool sirenReady = false;float timerClock = 0;                // timer counts per secondconst int WAIL_STEPS = 400;          // pitch steps in one up-and-down sweepuint32_t wailFull[WAIL_STEPS];       // timer counts per whole wave at each stepuint32_t stepCounts = 1;             // timer counts in one stepconst uint16_t DEFAULT_DUTY = 500;volatile uint16_t dutyPm = DEFAULT_DUTY;volatile bool wailing = false;volatile int wailIdx = 0;volatile uint32_t wailAcc = 0;volatile uint32_t curFull = 1;       // counts per whole wave right nowvolatile uint32_t activeLen = 1;     // length of the phase that is runninguint32_t phaseLen(uint32_t full, bool high) {  uint32_t on = (uint32_t)((uint64_t)full * dutyPm / 1000);  return high ? on : full - on;}void sirenTick(timer_callback_args_t *) {  buzLevel = !buzLevel;  digitalWrite(BUZ_A, buzLevel);  digitalWrite(BUZ_A2, buzLevel);  if (BUZ_B >= 0) digitalWrite(BUZ_B, !buzLevel);  if (wailing) {    wailAcc += activeLen;    if (wailAcc >= stepCounts) {      wailAcc -= stepCounts;      if (++wailIdx >= WAIL_STEPS) wailIdx = 0;      curFull = wailFull[wailIdx];    }  }  activeLen = phaseLen(curFull, buzLevel);   // what the buffer loaded for this phase  sirenTimer.set_period(phaseLen(curFull, !buzLevel));}uint32_t fullWaveCounts(float hz) {  return (uint32_t)(timerClock / hz + 0.5f);}void sirenSetup() {  uint8_t type = 0;  int8_t ch = FspTimer::get_available_timer(type);  if (ch < 0) { Serial.println(F("No free timer for the siren")); return; }  sirenTimer.begin(TIMER_MODE_PERIODIC, type, ch, 4800.0f, 50.0f, sirenTick, nullptr);  sirenTimer.setup_overflow_irq(4);  // ahead of the LED matrix and Wi-Fi interrupts  sirenTimer.open();  sirenTimer.stop();  sirenTimer.set_period_buffer(true);  timerClock = (float)sirenTimer.get_period_raw() * 4800.0f;  stepCounts = (uint32_t)(timerClock * WAIL_MS / WAIL_STEPS / 1000.0f);  int half = WAIL_STEPS / 2;  for (int i = 0; i < WAIL_STEPS; i++) {    float f = i < half ? WAIL_LOW + (WAIL_HIGH - WAIL_LOW) * (float)i / half                       : WAIL_HIGH - (WAIL_HIGH - WAIL_LOW) * (float)(i - half) / half;    wailFull[i] = fullWaveCounts(f);  }  sirenReady = true;}void startTimer() {  if (!sounding) {    sirenTimer.start();    sounding = true;  }}// A steady note.void soundOn(unsigned int hz) {  if (!sirenReady) return;  noInterrupts();  wailing = false;  curFull = fullWaveCounts(hz);  activeLen = phaseLen(curFull, false);  interrupts();  if (!sounding) sirenTimer.set_period(phaseLen(curFull, true));  startTimer();}// The up-and-down siren (runs by itself until soundOff).void wailOn() {  if (!sirenReady || (wailing && sounding)) return;  noInterrupts();  wailIdx = 0;  wailAcc = 0;  curFull = wailFull[0];  activeLen = phaseLen(curFull, false);  wailing = true;  interrupts();  if (!sounding) sirenTimer.set_period(phaseLen(curFull, true));  startTimer();}void soundOff() {  if (sounding && sirenReady) sirenTimer.stop();  sounding = false;  wailing = false;  buzLevel = false;  digitalWrite(BUZ_A, LOW);  digitalWrite(BUZ_A2, LOW);  if (BUZ_B >= 0) digitalWrite(BUZ_B, LOW);  deafUntil = millis() + DEAF_MS;}void tone2(unsigned int hz, unsigned int ms) {  if (!muted) soundOn(hz);  digitalWrite(LIGHT, HIGH);  delay(ms);  soundOff();  digitalWrite(LIGHT, LOW);}void click()    { tone2(2400, 25); }void twoBeeps() { tone2(2400, 80); delay(80); tone2(2400, 80); }void goodTone() { tone2(1800, 100); tone2(2700, 160); }void badTone()  { tone2(500, 450); }// Called every loop while the siren should be on: keeps it wailing, flashes the light.void updateSiren(unsigned long now) {  digitalWrite(LIGHT, ((now - stateStart) / 100) % 2 == 0);  if (muted) { if (sounding) soundOff(); }  else wailOn();}// ---------- Phone alerts (ntfy) ----------char topic[17];Note notes[6];char armedBy[10] = "keypad"; // who armed it, for the "armed" alertunsigned long lastNoteFail = 0;void queueNote(const char *title, const char *body, byte prio, const char *tags) {  for (Note &n : notes) {    if (n.used) continue;    n.used = true;    n.prio = prio;    strncpy(n.title, title, sizeof(n.title) - 1); n.title[sizeof(n.title) - 1] = 0;    strncpy(n.body, body, sizeof(n.body) - 1);    n.body[sizeof(n.body) - 1] = 0;    strncpy(n.tags, tags, sizeof(n.tags) - 1);    n.tags[sizeof(n.tags) - 1] = 0;    return;  }}// ---------- Wi-Fi and the app ----------char wifiSsid[33];char wifiPass[65];bool haveWifi = false;bool setupMode = false;bool wifiUp = false;unsigned long lastWifiTry = 0;unsigned long lastWifiCheck = 0;WiFiServer server(80);char netNames[12][33];int netCount = 0;byte wrongTries = 0;unsigned long lockUntil = 0;const char *ipStr() {  static char buf[16];  IPAddress ip = setupMode ? IPAddress(192, 168, 4, 1) : WiFi.localIP();  snprintf(buf, sizeof buf, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);  return buf;}void readEepromString(int at, char *dst, int size) {  for (int i = 0; i < size; i++) dst[i] = EEPROM.read(at + i);  dst[size - 1] = 0;}void writeEepromString(int at, const char *src, int size) {  for (int i = 0; i < size; i++) {    char c = i < (int)strlen(src) ? src[i] : 0;    EEPROM.update(at + i, c);  }}void loadWifi() {  haveWifi = EEPROM.read(EE_WIFI_MAGIC) == WIFI_MAGIC;  if (haveWifi) {    readEepromString(EE_SSID, wifiSsid, sizeof wifiSsid);    readEepromString(EE_PASS, wifiPass, sizeof wifiPass);    haveWifi = wifiSsid[0] != 0;  }}void loadTopic() {  if (EEPROM.read(EE_TOPIC_MAGIC) == TOPIC_MAGIC) {    readEepromString(EE_TOPIC, topic, sizeof topic);    if (strlen(topic) == 16) return;  }  // A random name nobody would guess, so only you get the alerts.  unsigned long seed = micros();  for (int i = 0; i < 32; i++) seed = seed * 31 + analogRead(A3) + (analogRead(A4) << 4) + (analogRead(A5) << 8);  randomSeed(seed);  strcpy(topic, "alarm-");  const char *chars = "abcdefghijkmnpqrstuvwxyz23456789";  for (int i = 6; i < 16; i++) topic[i] = chars[random(32)];  topic[16] = 0;  writeEepromString(EE_TOPIC, topic, sizeof topic);  EEPROM.update(EE_TOPIC_MAGIC, TOPIC_MAGIC);}void startSetupMode() {  setupMode = true;  Serial.println(F("Wi-Fi setup: looking for networks..."));  netCount = 0;  int n = WiFi.scanNetworks();  for (int i = 0; i < n && netCount < 12; i++) {    const char *s = WiFi.SSID(i);    if (!s || !s[0]) continue;    bool dup = false;    for (int j = 0; j < netCount; j++) if (!strcmp(netNames[j], s)) dup = true;    if (dup) continue;    strncpy(netNames[netCount], s, 32);    netNames[netCount][32] = 0;    netCount++;  }  WiFi.config(IPAddress(192, 168, 4, 1));  if (WiFi.beginAP(SETUP_SSID) != WL_AP_LISTENING) {    Serial.println(F("Couldn't start the setup network"));    return;  }  delay(1000);  server.begin();  Serial.print(F("Setup network \""));  Serial.print(SETUP_SSID);  Serial.println(F("\" is on. Join it and open http://192.168.4.1"));  addEvent("Wi-Fi setup mode");}bool connectWifi() {  lastWifiTry = millis();  Serial.print(F("Joining Wi-Fi \""));  Serial.print(wifiSsid);  Serial.println(F("\"..."));  int st = WiFi.begin(wifiSsid, wifiPass);  if (st != WL_CONNECTED) {    Serial.print(F("Couldn't join the Wi-Fi ("));    Serial.print(st == WL_NO_SSID_AVAIL ? F("network not found / too weak")               : st == WL_CONNECT_FAILED ? F("refused - usually the password")               : F("no answer"));    Serial.print(F(", code "));    Serial.print(st);    Serial.println(F(") - will keep trying every minute"));    return false;  }  unsigned long t0 = millis();  while (WiFi.localIP() == IPAddress(0, 0, 0, 0) && millis() - t0 < 8000) delay(100);  wifiUp = true;  server.begin();  Serial.print(F("On Wi-Fi. App: http://"));  Serial.println(ipStr());  char body[64];  snprintf(body, sizeof body, "Tap to open the app: http://%s/", ipStr());  queueNote("Alarm is online", body, 2, "house");  addEvent("Connected to Wi-Fi");  return true;}void startWifi() {  if (WiFi.status() == WL_NO_MODULE) {    Serial.println(F("Wi-Fi chip not answering - running without Wi-Fi"));    return;  }  bool force = EEPROM.read(EE_FORCE_SETUP) == FORCE_MAGIC;  if (force) EEPROM.update(EE_FORCE_SETUP, 0);  if (force || !haveWifi) startSetupMode();  else connectWifi();}// Keep the Wi-Fi going without getting in the way of the alarm: never while// someone needs the keypad (arming or the countdown).void tendWifi(unsigned long now) {  if (setupMode || !haveWifi) return;  if (now - lastWifiCheck < 10000UL) return;  lastWifiCheck = now;  if (wifiUp && WiFi.status() != WL_CONNECTED) {    wifiUp = false;    Serial.println(F("Lost the Wi-Fi"));  }  if (!wifiUp && (state == DISARMED || state == ARMED || state == ALARM) && now - lastWifiTry >= 60000UL)    connectWifi();}bool postNote(const Note &n, unsigned long waitMs = 5000, int connectMs = 0) {  WiFiSSLClient cl;  if (connectMs) cl.setConnectionTimeout(connectMs);  if (!cl.connect("ntfy.sh", 443)) return false;  cl.print("POST /"); cl.print(topic); cl.println(" HTTP/1.1");  cl.println("Host: ntfy.sh");  cl.print("Title: "); cl.println(n.title);  cl.print("Priority: "); cl.println(n.prio);  if (n.tags[0]) { cl.print("Tags: "); cl.println(n.tags); }  cl.print("Click: http://"); cl.print(ipStr()); cl.println("/");  cl.print("Content-Length: "); cl.println(strlen(n.body));  cl.println("Connection: close");  cl.println();  cl.print(n.body);  unsigned long t0 = millis();  char line[24];  int len = 0;  while (millis() - t0 < waitMs && len < (int)sizeof(line) - 1) {    if (!cl.available()) { delay(5); continue; }    char c = cl.read();    if (c == '\n') break;    line[len++] = c;  }  line[len] = 0;  cl.stop();  return strstr(line, " 200") != nullptr;}// Motion seen while armed: tell the phone right away (with short time limits,// since the countdown is about to start). If it can't go now, it's queued.void sendMotionAlert() {  Note m = {true, 4, "Motion detected", "Movement seen - 15 s to type the code before the siren.", "warning"};  if (wifiUp) {    digitalWrite(LIGHT, HIGH);    bool ok = postNote(m, 2000, 3000);    digitalWrite(LIGHT, LOW);    if (ok) {      Serial.println(F("Alert sent: Motion detected"));      return;    }  }  queueNote(m.title, m.body, m.prio, m.tags);}// Sends waiting alerts. Each one takes a second or two, so not while someone// is using the keypad.void sendNotes(unsigned long now) {  if (!wifiUp || state == ENTRY || state == ARMING) return;  if (lastNoteFail && now - lastNoteFail < 30000UL) return;  for (Note &n : notes) {    if (!n.used) continue;    if (postNote(n)) {      n.used = false;      lastNoteFail = 0;      Serial.print(F("Alert sent: "));      Serial.println(n.title);    } else {      lastNoteFail = millis();      Serial.println(F("Couldn't send an alert - will try again"));    }    return;   // one at a time, back to the alarm in between  }}// ----- tiny web server -----bool readLine(WiFiClient &c, char *buf, int size, unsigned long timeout) {  int n = 0;  unsigned long t0 = millis();  while (millis() - t0 < timeout) {    if (!c.available()) { if (!c.connected()) break; delay(1); continue; }    char ch = c.read();    if (ch == '\r') continue;    if (ch == '\n') { buf[n] = 0; return true; }    if (n < size - 1) buf[n++] = ch;  }  buf[n] = 0;  return n > 0;}void sendHead(WiFiClient &c, int status, const char *type, size_t len) {  c.print("HTTP/1.1 ");  c.print(status);  c.println(status == 200 ? " OK" : status == 404 ? " Not Found" : " Bad Request");  c.print("Content-Type: "); c.println(type);  c.print("Content-Length: "); c.println(len);  c.println("Cache-Control: no-store");  c.println("Connection: close");  c.println();}void sendBytes(WiFiClient &c, const char *type, const uint8_t *p, size_t len) {  sendHead(c, 200, type, len);  while (len) {    size_t k = len > 1024 ? 1024 : len;    c.write(p, k);    p += k;    len -= k;  }}void sendText(WiFiClient &c, const char *type, const char *s) {  sendBytes(c, type, (const uint8_t *)s, strlen(s));}// Adds s to a JSON string being built, with quotes and escapes.void jsonStr(char *out, size_t size, const char *s) {  size_t n = strlen(out);  if (n + 2 >= size) return;  out[n++] = '"';  for (; *s && n + 3 < size; s++) {    if (*s == '"' || *s == '\\') out[n++] = '\\';    if ((unsigned char)*s < 0x20) continue;    out[n++] = *s;  }  out[n++] = '"';  out[n] = 0;}void jsonAdd(char *out, size_t size, const char *s) {  strncat(out, s, size - strlen(out) - 1);}// Value of key in a form body like "a=arm&c=1234", with %xx and + decoded.bool formValue(const char *body, const char *key, char *out, int size) {  int kl = strlen(key);  const char *p = body;  while (p && *p) {    if (!strncmp(p, key, kl) && p[kl] == '=') {      p += kl + 1;      int n = 0;      while (*p && *p != '&' && n < size - 1) {        if (*p == '+') { out[n++] = ' '; p++; }        else if (*p == '%' && p[1] && p[2]) {          char hex[3] = {p[1], p[2], 0};          out[n++] = (char)strtol(hex, nullptr, 16);          p += 3;        } else out[n++] = *p++;      }      out[n] = 0;      return true;    }    p = strchr(p, '&');    if (p) p++;  }  out[0] = 0;  return false;}const char *stateName() {  switch (state) {    case DISARMED: return "OFF";    case ARMING:   return "ARMING";    case ARMED:    return "ARMED";    case ENTRY:    return "COUNTDOWN";    case ALARM:    return "ALARM";  }  return "?";}void sendStatus(WiFiClient &c) {  static char j[1400];  unsigned long now = millis();  long left = 0;  if (state == ARMING) left = ((long)EXIT_MS - (long)(now - stateStart) + 999) / 1000;  if (state == ENTRY) left = ((long)ENTRY_MS - (long)(now - stateStart) + 999) / 1000;  if (left < 0) left = 0;  long locked = (lockUntil && (long)(lockUntil - now) > 0) ? (long)(lockUntil - now) / 1000 + 1 : 0;  snprintf(j, sizeof j,           "{\"state\":\"%s\",\"left\":%ld,\"muted\":%s,\"motion\":%s,\"alarms\":%lu,\"locked\":%ld,\"topic\":\"%s\",\"events\":[",           stateName(), left, muted ? "true" : "false", digitalRead(PIR_PIN) ? "true" : "false",           motionCount, locked, topic);  for (int i = 0; i < eventCount; i++) {    char item[24];    snprintf(item, sizeof item, "%s{\"ago\":%lu,\"m\":", i ? "," : "", (now - events[i].ms) / 1000);    jsonAdd(j, sizeof j, item);    jsonStr(j, sizeof j, events[i].m);    jsonAdd(j, sizeof j, "}");  }  jsonAdd(j, sizeof j, "]}");  sendText(c, "application/json", j);}void reply(WiFiClient &c, bool ok, const char *msg) {  char j[120] = "";  jsonAdd(j, sizeof j, ok ? "{\"ok\":true,\"msg\":" : "{\"ok\":false,\"msg\":");  jsonStr(j, sizeof j, msg);  jsonAdd(j, sizeof j, "}");  sendText(c, "application/json", j);}void handleCmd(WiFiClient &c, const char *body) {  char a[12], given[12];  formValue(body, "a", a, sizeof a);  formValue(body, "c", given, sizeof given);  unsigned long now = millis();  if (lockUntil && (long)(lockUntil - now) > 0) { reply(c, false, "Too many wrong codes - wait a minute"); return; }  if (strlen(given) != codeLen || memcmp(given, code, codeLen)) {    if (++wrongTries >= 5) { wrongTries = 0; lockUntil = now + 60000UL; addEvent("Wrong codes on the phone"); }    reply(c, false, "Wrong code");    return;  }  wrongTries = 0;  if (!strcmp(a, "arm")) {    if (state != DISARMED) { reply(c, false, "It's already on"); return; }    reply(c, true, "Arming - 15 s to leave");    goodTone();    strcpy(armedBy, "phone");    setState(ARMING);    addEvent("Armed from phone");  } else if (!strcmp(a, "disarm")) {    if (state == DISARMED) { reply(c, false, "It's already off"); return; }    reply(c, true, "Turned off");    turnOff("phone");  } else if (!strcmp(a, "test")) {    if (state != DISARMED) { reply(c, false, "Turn it off first"); return; }    reply(c, true, "Testing the siren");    stateStart = millis();    testUntil = millis() + 3000;    addEvent("Siren test");  } else if (!strcmp(a, "mute")) {    muted = !muted;    EEPROM.update(EE_MUTE, muted ? MUTE_MAGIC : 0xFF);    if (muted && sounding) soundOff();    reply(c, true, muted ? "Sound off (light only)" : "Sound on");  } else {    reply(c, false, "Unknown command");  }}void sendSetupInfo(WiFiClient &c) {  static char j[700];  snprintf(j, sizeof j, "{\"topic\":\"%s\",\"nets\":[", topic);  for (int i = 0; i < netCount; i++) {    if (i) jsonAdd(j, sizeof j, ",");    jsonStr(j, sizeof j, netNames[i]);  }  jsonAdd(j, sizeof j, "]}");  sendText(c, "application/json", j);}void handleWifiForm(WiFiClient &c, const char *body) {  char s[33], p[65];  formValue(body, "s", s, sizeof s);  formValue(body, "p", p, sizeof p);  if (!s[0]) { reply(c, false, "No Wi-Fi name"); return; }  writeEepromString(EE_SSID, s, sizeof wifiSsid);  writeEepromString(EE_PASS, p, sizeof wifiPass);  EEPROM.update(EE_WIFI_MAGIC, WIFI_MAGIC);  reply(c, true, "Saved");  c.flush();  delay(500);  c.stop();  Serial.print(F("Wi-Fi saved: \""));  Serial.print(s);  Serial.println(F("\". Restarting to join it."));  delay(1000);  NVIC_SystemReset();}void handleWeb() {  static unsigned long lastPoll = 0;  if (!wifiUp && !setupMode) return;  if (millis() - lastPoll < 20) return;  lastPoll = millis();  WiFiClient c = server.available();  if (!c) return;  char req[120], hdr[120];  if (!readLine(c, req, sizeof req, 500)) { c.stop(); return; }  int contentLen = 0;  while (readLine(c, hdr, sizeof hdr, 500) && hdr[0])    if (!strncasecmp(hdr, "Content-Length:", 15)) contentLen = atoi(hdr + 15);  static char body[260];  int n = 0;  unsigned long t0 = millis();  while (n < contentLen && n < (int)sizeof(body) - 1 && millis() - t0 < 500) {    if (c.available()) body[n++] = c.read();    else delay(1);  }  body[n] = 0;  bool post = !strncmp(req, "POST ", 5);  char *path = strchr(req, ' ');  if (!path) { c.stop(); return; }  path++;  char *end = strpbrk(path, " ?");  if (end) *end = 0;  if (setupMode) {    if (post && !strcmp(path, "/api/wifi")) handleWifiForm(c, body);    else if (!strcmp(path, "/api/setupinfo")) sendSetupInfo(c);    else sendText(c, "text/html; charset=utf-8", SETUP_HTML);   // every other address shows the setup page  } else {    if (!strcmp(path, "/") || !strcmp(path, "/index.html")) sendText(c, "text/html; charset=utf-8", APP_HTML);    else if (!strcmp(path, "/api/status")) sendStatus(c);    else if (post && !strcmp(path, "/api/cmd")) handleCmd(c, body);    else if (!strcmp(path, "/manifest.json")) sendText(c, "application/manifest+json", MANIFEST_JSON);    else if (!strcmp(path, "/icon.png")) sendBytes(c, "image/png", ICON_PNG, sizeof ICON_PNG);    else { sendHead(c, 404, "text/plain", 9); c.print("Not found"); }  }  c.flush();  c.stop();}// ---------- State ----------void setState(State s) {  state = s;  stateStart = millis();  EEPROM.update(EE_STATE, s == ARMING ? ARMED : s);   // power loss while arming = armed  switch (s) {    case DISARMED: Serial.println(F("OFF - disarmed")); break;    case ARMING:   Serial.println(F("Arming - leave within 15 s")); break;    case ARMED:    Serial.println(F("ARMED - watching for motion")); break;    case ENTRY:    Serial.println(F("Countdown - 15 s to type the code")); break;    case ALARM:    Serial.println(F("ALARM - siren on")); break;  }}bool sensorWarm() {  return millis() - warmStart >= WARMUP_MS;}// Turns the alarm off, from the keypad or the phone.void turnOff(const char *by) {  State was = state;  bool wasAlarm = state == ALARM;  if (wasAlarm) {    soundOff();    digitalWrite(LIGHT, LOW);    delay(300);  }  goodTone();  setState(DISARMED);  char m[40];  snprintf(m, sizeof m, "Turned off by %s", by);  addEvent(m);  char body[80];  if (wasAlarm) {    snprintf(body, sizeof body, "The siren was turned off by %s.", by);    queueNote("Alarm stopped", body, 4, "white_check_mark");  } else if (was == ENTRY) {    snprintf(body, sizeof body, "Movement was seen, then it was turned off by %s in time.", by);    queueNote("Alarm turned off", body, 3, "unlock");  } else if (was == ARMED) {    snprintf(body, sizeof body, "Turned off by %s.", by);    queueNote("Alarm turned off", body, 3, "unlock");  }   // cancelled while arming: it was never on, so no alert}// ---------- Code ----------void loadCode() {  if (EEPROM.read(EE_CODE_MAGIC) == CODE_MAGIC) {    codeLen = EEPROM.read(EE_CODE_LEN);    if (codeLen >= 4 && codeLen <= MAX_CODE) {      for (byte i = 0; i < codeLen; i++) code[i] = EEPROM.read(EE_CODE + i);      return;    }  }  codeLen = strlen(DEFAULT_CODE);  memcpy(code, DEFAULT_CODE, codeLen);}void saveCode(const char *c, byte len) {  memcpy(code, c, len);  codeLen = len;  EEPROM.update(EE_CODE_LEN, len);  for (byte i = 0; i < len; i++) EEPROM.update(EE_CODE + i, c[i]);  EEPROM.update(EE_CODE_MAGIC, CODE_MAGIC);}bool typedMatches() {  if (typedLen < codeLen) return false;  return memcmp(typed + typedLen - codeLen, code, codeLen) == 0;}void codeAccepted() {  if (state == DISARMED) {    goodTone();    strcpy(armedBy, "keypad");    setState(ARMING);    addEvent("Armed by keypad");  } else {    turnOff("keypad");  }}void handleChange(char k) {  if (k == '*') {    changeStep = 0;    badTone();    Serial.println(F("Code change cancelled"));    return;  }  if (k != '#') {    if (newLen >= MAX_CODE) {      changeStep = 0;      badTone();      Serial.println(F("Code change cancelled - too long (8 keys max)"));      return;    }    newCode[newLen++] = k;    click();    return;  }  if (changeStep == 1) {    if (newLen < 4) {      changeStep = 0;      badTone();      Serial.println(F("Code change cancelled - too short (4 keys min)"));      return;    }    memcpy(firstCode, newCode, newLen);    firstLen = newLen;    newLen = 0;    changeStep = 2;    twoBeeps();    Serial.println(F("Type the new code again, then #"));  } else {    changeStep = 0;    if (newLen == firstLen && memcmp(newCode, firstCode, newLen) == 0) {      saveCode(newCode, newLen);      goodTone();      Serial.println(F("New code saved"));      addEvent("Code changed");    } else {      badTone();      Serial.println(F("The two codes didn't match - kept the old code"));    }  }}void onKey(char k) {  lastKeyAt = millis();  if (echoKeys) { Serial.print(F("Key: ")); Serial.println(k); }  if (changeStep) { handleChange(k); return; }  if (state == DISARMED) {    hashCount = k == '#' ? hashCount + 1 : 0;    if (hashCount >= 5) {       // # five times while OFF: Wi-Fi setup      Serial.println(F("Restarting into Wi-Fi setup"));      twoBeeps();      EEPROM.update(EE_FORCE_SETUP, FORCE_MAGIC);      delay(300);      NVIC_SystemReset();    }  }  if (k == '*' && state == DISARMED) {    changeStep = 1;    newLen = 0;    twoBeeps();    Serial.println(F("Changing the code: type the new one, then #"));    return;  }  if (state != ALARM) click();  if (k == '*' || k == '#') {     // clears what's been typed    typedLen = 0;    return;  }  if (typedLen == MAX_CODE) {    memmove(typed, typed + 1, MAX_CODE - 1);    typedLen--;  }  typed[typedLen++] = k;  if (typedMatches()) {    typedLen = 0;    codeAccepted();  }}// ---------- Keypad ----------char scanKeypad() {  char found = 0;  for (int r = 0; r < 4; r++) {    pinMode(ROW_PINS[r], OUTPUT);    digitalWrite(ROW_PINS[r], LOW);    delayMicroseconds(5);    for (int c = 0; c < 4; c++)      if (!digitalRead(COL_PINS[c])) found = KEYS[r][c];    pinMode(ROW_PINS[r], INPUT_PULLUP);  }  return found;}void pollKeypad() {  static unsigned long lastScan = 0;  static char lastRead = 0, stableKey = 0;  static byte same = 0;  if (millis() - lastScan < 10) return;  lastScan = millis();  char k = scanKeypad();  if (k != lastRead) { lastRead = k; same = 0; return; }  if (same < 3) same++;  if (same == 2 && k != stableKey) {   // the same for 30 ms: a real press    stableKey = k;    if (k) onKey(k);  }}// ---------- Motion sensor power and wiring checks ----------void powerSensor() {  pinMode(pirGnd, OUTPUT);  digitalWrite(pirGnd, LOW);  pinMode(pirVcc, OUTPUT);  digitalWrite(pirVcc, HIGH);}bool powerPinsOk() {  return digitalRead(pirVcc) == HIGH && digitalRead(pirGnd) == LOW;}// Tells "something is holding OUT HIGH" apart from "nothing is connected", which// both read HIGH with the pull-up: pull the pin LOW for a moment and let go.// Something driving it brings it straight back up; a loose wire stays LOW.bool outDriven() {  digitalWrite(PIR_PIN, LOW);  pinMode(PIR_PIN, OUTPUT);  delayMicroseconds(10);  pinMode(PIR_PIN, INPUT);  delayMicroseconds(5);  bool driven = digitalRead(PIR_PIN);  pinMode(PIR_PIN, INPUT_PULLUP);  return driven;}// A sensor with VCC and GND swapped isn't damaged (it has a protection diode),// but its GND pin is then at 5V and leaks through the chip to OUT, so OUT looks// like non-stop motion. To spot that, cut the power for half a millisecond:// a sensor powered the right way keeps going on its capacitors, while the// back-to-front one drops OUT straight away. If that happens, swap pins 2 and 4.void checkPower() {  if (!digitalRead(PIR_PIN)) {      // only a properly powered sensor can pull OUT LOW    powerConfirmed = true;    Serial.println(F("Sensor power: OK"));    return;  }  if (!outDriven()) return;         // loose OUT wire: nothing to learn yet  digitalWrite(pirVcc, LOW);  delayMicroseconds(500);  bool held = outDriven();  digitalWrite(pirVcc, HIGH);  if (held) {    powerConfirmed = true;    Serial.println(F("Sensor power: OK"));    return;  }  int t = pirVcc; pirVcc = pirGnd; pirGnd = t;  swaps++;  powerSensor();  delay(2);  if (swaps >= 2 || !powerPinsOk()) {    if (swaps < 2 || !powerPinsOk()) { t = pirVcc; pirVcc = pirGnd; pirGnd = t; powerSensor(); }    powerConfirmed = true;          // stop trying    Serial.println(F("Sensor power: couldn't work it out - please check the VCC and GND wires"));    return;  }  Serial.println(F("Sensor power: VCC and GND wires are the other way round - fixed it in the program"));  warmStart = millis();             // it has to settle again}void printSensorCheck() {  if (!powerPinsOk()) {    Serial.println(F("Sensor: power pins 2/4 are overloaded - check the VCC and GND wires"));  } else if (!digitalRead(PIR_PIN)) {    Serial.println(F("Sensor: connected, no motion"));  } else if (outDriven()) {    Serial.println(F("Sensor: OUT is HIGH (motion right now)"));  } else {    Serial.println(F("Sensor: not answering - OUT wire loose, or no power on VCC/GND"));  }  Serial.print(F("Sensor power: VCC on pin "));  Serial.print(pirVcc);  Serial.print(F(", GND on pin "));  Serial.print(pirGnd);  Serial.println(powerConfirmed ? F(" (confirmed)") : F(" (still checking)"));}void printWifiInfo() {  if (setupMode) {    Serial.print(F("Wi-Fi: setup mode, network \""));    Serial.print(SETUP_SSID);    Serial.println(F("\", page http://192.168.4.1"));  } else if (!haveWifi) {    Serial.println(F("Wi-Fi: not set up"));  } else {    Serial.print(F("Wi-Fi: \""));    Serial.print(wifiSsid);    Serial.print(wifiUp ? F("\" connected, app http://") : F("\" not connected"));    if (wifiUp) {      Serial.print(ipStr());      Serial.print(F("/  signal "));      Serial.print(WiFi.RSSI());      Serial.print(F(" dBm"));    }    Serial.println();  }  Serial.print(F("ntfy topic: "));  Serial.println(topic);}void printStatus() {  Serial.print(F("State: "));  Serial.print(stateName());  Serial.print(sensorWarm() ? F(" | sensor ready") : F(" | sensor warming up"));  Serial.print(F(" | sound "));  Serial.print(muted ? F("OFF") : F("ON"));  Serial.print(F(" | code length "));  Serial.print(codeLen);  Serial.print(F(" | alarms so far: "));  Serial.println(motionCount);  printSensorCheck();  printWifiInfo();}void handleSerial() {  while (Serial.available()) {    char c = Serial.read();    if (c == '?') {      printStatus();    } else if (c == 'i') {      printWifiInfo();    } else if (c == 'n' && !setupMode) {   // Wi-Fi networks in range, with signal strength      Serial.print(F("Wi-Fi chip firmware: "));      Serial.println(WiFi.firmwareVersion());      int n = WiFi.scanNetworks();      Serial.print(n);      Serial.println(F(" networks:"));      for (int i = 0; i < n; i++) {        Serial.print(F("  "));        Serial.print(WiFi.RSSI(i));        Serial.print(F(" dBm  "));        Serial.println(WiFi.SSID(i));      }    } else if (c == 'V') {          // the siren at 3 strengths, to compare by ear      const uint16_t duties[3] = {500, 300, 150};      for (int k = 0; k < 3; k++) {        dutyPm = duties[k];        Serial.print(F("Version "));        Serial.print(k + 1);        Serial.print(F(": push "));        Serial.print(duties[k] / 10);        Serial.println(F("%"));        wailOn();        delay(3500);        soundOff();        delay(1500);      }      dutyPm = DEFAULT_DUTY;    } else if (c == 'T') {          // longer test, with the program busy for 1.5 s      Serial.println(F("Test siren, 6 s, busy for 1.5 s like when sending an alert"));      stateStart = millis();      testUntil = millis() + 6000;      updateSiren(millis());      delay(1500);    } else if (c == 't') {      Serial.println(F("Test siren"));      stateStart = millis();      testUntil = millis() + 3000;    } else if (c == 'm') {      muted = !muted;      EEPROM.update(EE_MUTE, muted ? MUTE_MAGIC : 0xFF);      if (muted && sounding) soundOff();      Serial.println(muted ? F("Sound OFF (light only)") : F("Sound ON"));    } else if (c == 'k') {      echoKeys = !echoKeys;      Serial.println(echoKeys ? F("Showing keys") : F("Not showing keys"));    } else if (c == 'd') {      if (state != DISARMED) turnOff("computer");    } else if (c == 'r') {      saveCode(DEFAULT_CODE, strlen(DEFAULT_CODE));      Serial.println(F("Code reset to the default"));    } else if (c == 'w') {      Serial.println(F("Restarting into Wi-Fi setup"));      EEPROM.update(EE_FORCE_SETUP, FORCE_MAGIC);      delay(300);      NVIC_SystemReset();    }  }}void updateMatrix(unsigned long now) {  switch (state) {    case DISARMED: showIcon(setupMode ? ICON_WIFI : ICON_OFF); break;    case ARMING:   showIcon((now / 500) % 2 ? ICON_ARMING : ICON_BLANK); break;    case ARMED:    showIcon(ICON_ARMED); break;    case ENTRY:    showIcon(ICON_COUNT); break;    case ALARM:    showIcon((now / 250) % 2 ? ICON_ALARM : ICON_BLANK); break;  }}void setup() {  Serial.begin(9600);  matrix.begin();  powerSensor();  pinMode(PIR_PIN, INPUT_PULLUP);   // reads HIGH if the OUT wire is missing, not random  pinMode(LIGHT, OUTPUT);  for (int i = 0; i < 4; i++) {    pinMode(ROW_PINS[i], INPUT_PULLUP);    pinMode(COL_PINS[i], INPUT_PULLUP);  }  pinMode(BUZ_A, OUTPUT);  digitalWrite(BUZ_A, LOW);  pinMode(BUZ_A2, OUTPUT);  digitalWrite(BUZ_A2, LOW);  if (BUZ_B >= 0) { pinMode(BUZ_B, OUTPUT); digitalWrite(BUZ_B, LOW); }  sirenSetup();  muted = EEPROM.read(EE_MUTE) == MUTE_MAGIC;  loadCode();  loadTopic();  loadWifi();  warmStart = millis();  Serial.println(F("Motion alarm (Wi-Fi) starting"));  byte saved = EEPROM.read(EE_STATE);  if (saved == ALARM) {    setState(ALARM);                // it was going off: keep going until the code    addEvent("Still going off after a restart");    queueNote("ALARM going off!", "The alarm restarted while going off, and it's still going.", 5, "rotating_light");  } else if (saved == ENTRY) {    setState(ENTRY);                // unplugged during the countdown: start it again  } else if (saved == ARMED) {    strcpy(armedBy, "restart");    setState(ARMING);    stateStart = millis() - EXIT_MS;   // no walk-away time needed, just the warm-up    twoBeeps();  } else {    setState(DISARMED);    twoBeeps();  }  updateMatrix(millis());  startWifi();}void loop() {  handleSerial();  pollKeypad();  unsigned long now = millis();  if (!powerConfirmed && now - lastPowerCheck >= 2000UL) {    lastPowerCheck = now;    checkPower();    now = millis();  }  if (changeStep && now - lastKeyAt >= CHANGE_TIMEOUT_MS) {    changeStep = 0;    badTone();    Serial.println(F("Code change cancelled - took too long"));  }  switch (state) {    case DISARMED:      if ((long)(testUntil - now) > 0) updateSiren(now);      else if (sounding) { soundOff(); digitalWrite(LIGHT, LOW); }      break;    case ARMING: {      unsigned long t = now - stateStart;      static unsigned long lastTick = 0;      if (t < EXIT_MS && now - lastTick >= 1000) {        lastTick = now;        tone2(2400, 40);      }      if (t >= EXIT_MS && sensorWarm()) {        tone2(2700, 300);        setState(ARMED);        char body[64];        if (!strcmp(armedBy, "restart")) snprintf(body, sizeof body, "Armed again after the alarm restarted.");        else snprintf(body, sizeof body, "Armed by %s. Watching for movement.", armedBy);        queueNote("Alarm armed", body, 3, "lock");      }      break;    }    case ARMED:      digitalWrite(LIGHT, (now - stateStart) % 2000 < 60);      if ((long)(now - deafUntil) >= 0 && digitalRead(PIR_PIN) && outDriven()) {        motionCount++;        Serial.print(F("MOTION #"));        Serial.println(motionCount);        addEvent("Motion - countdown");        setState(ENTRY);        sendMotionAlert();        stateStart = millis();   // the 15 s starts once the alert has gone      }      break;    case ENTRY: {      // A warning beep every second, every half second in the last 5 s.      unsigned long t = now - stateStart;      static unsigned long lastBeep = 0;      unsigned long gap = t < ENTRY_MS - 5000 ? 1000 : 500;      if (t >= ENTRY_MS) {        setState(ALARM);        addEvent("ALARM! Siren on");        queueNote("ALARM going off!", "Movement was seen and the code wasn't typed in time.", 5, "rotating_light");      } else if (now - lastBeep >= gap || t < 50) {        lastBeep = now;        tone2(2000, 70);      }      break;    }    case ALARM:      updateSiren(now);      break;  }  updateMatrix(now);  handleWeb();  now = millis();  sendNotes(now);  tendWifi(now);}