WiFi Monkey Deterrent Speaker

#include <Arduino.h>
#include <WiFi.h>
#include <WebServer.h>
#include <ESPmDNS.h>
#include <Preferences.h>
#include <DFRobotDFPlayerMini.h>


// Forward declarations
bool cooldownActive();
String statusJson();
bool playDeterrent(const char *source);
void handleTrigger();
void handleStatus();
void handleSetupForm();
void handleSaveWifi();
void startSetupAccessPoint();
bool connectToLocalWifi();
void setupNetwork();

constexpr int DFPLAYER_RX_PIN = 16;  // DFPlayer TX -> ESP32 RX
constexpr int DFPLAYER_TX_PIN = 17;  // ESP32 TX -> 1k resistor -> DFPlayer RX
constexpr int TEST_BUTTON_PIN = 27;
constexpr uint32_t COOLDOWN_MS = 60000UL;
constexpr uint8_t FIRST_TRACK = 1;
constexpr uint8_t LAST_TRACK = 4;
constexpr uint8_t PLAYBACK_VOLUME = 26;  // DFPlayer range: 0 to 30

const char *SETUP_AP_NAME = "GardenDeterrent-Setup";
const char *SETUP_AP_PASSWORD = "change-me-now";
const char *TRIGGER_KEY = "replace-this-local-key";

HardwareSerial dfSerial(2);
DFRobotDFPlayerMini player;
WebServer server(80);
Preferences preferences;

bool playerReady = false;
bool wasButtonPressed = false;
uint32_t lastTriggerMs = 0;
String stationSsid;
String stationPassword;

bool cooldownActive() {
  return lastTriggerMs != 0 && (uint32_t)(millis() - lastTriggerMs) < COOLDOWN_MS;
}

String statusJson() {
  String json = "{\"ready\":" + String(playerReady ? "true" : "false");
  json += ",\"cooldown\":" + String(cooldownActive() ? "true" : "false");
  json += ",\"cooldown_remaining_seconds\":";
  if (cooldownActive()) {
    json += String((COOLDOWN_MS - (millis() - lastTriggerMs) + 999UL) / 1000UL);
  } else {
    json += "0";
  }
  json += ",\"ip\":\"" + WiFi.localIP().toString() + "\"}";
  return json;
}

bool playDeterrent(const char *source) {
  if (!playerReady) {
    server.send(503, "application/json", "{\"accepted\":false,\"reason\":\"audio_player_not_ready\"}");
    return false;
  }
  if (cooldownActive()) {
    server.send(429, "application/json", "{\"accepted\":false,\"reason\":\"cooldown_active\"}");
    return false;
  }

  uint8_t track = random(FIRST_TRACK, LAST_TRACK + 1);
  player.playMp3Folder(track);
  lastTriggerMs = millis();
  Serial.printf("Triggered by %s; playing /mp3/%04u.mp3\n", source, track);
  return true;
}

void handleTrigger() {
  String suppliedKey = server.hasArg("key") ? server.arg("key") : "";
  if (suppliedKey != TRIGGER_KEY) {
    server.send(403, "application/json", "{\"accepted\":false,\"reason\":\"invalid_key\"}");
    return;
  }
  if (playDeterrent("network")) {
    server.send(202, "application/json", "{\"accepted\":true,\"cooldown_seconds\":60}");
  }
}

void handleStatus() {
  server.send(200, "application/json", statusJson());
}

void handleSetupForm() {
  const char page[] =
      "<!doctype html><html><body><h2>Garden deterrent Wi-Fi setup</h2>"
      "<p>This setup page is local to the device and never uses the internet.</p>"
      "<form method='POST' action='/save'><label>Garden Wi-Fi name <input name='ssid' required></label><br>"
      "<label>Garden Wi-Fi password <input type='password' name='password' required></label><br>"
      "<button type='submit'>Save and restart</button></form></body></html>";
  server.send(200, "text/html", page);
}

void handleSaveWifi() {
  if (!server.hasArg("ssid") || !server.hasArg("password") || server.arg("ssid").length() == 0) {
    server.send(400, "text/plain", "Wi-Fi name and password are required.");
    return;
  }
  preferences.begin("deterrent", false);
  preferences.putString("ssid", server.arg("ssid"));
  preferences.putString("password", server.arg("password"));
  preferences.end();
  server.send(200, "text/html", "Saved. The device will restart now and join the local garden Wi-Fi.");
  delay(1000);
  ESP.restart();
}

void startSetupAccessPoint() {
  WiFi.mode(WIFI_AP);
  WiFi.softAP(SETUP_AP_NAME, SETUP_AP_PASSWORD);
  server.on("/", HTTP_GET, handleSetupForm);
  server.on("/save", HTTP_POST, handleSaveWifi);
  server.on("/status", HTTP_GET, handleStatus);
  server.begin();
  Serial.print("Setup hotspot IP: ");
  Serial.println(WiFi.softAPIP());
}

bool connectToLocalWifi() {
  WiFi.mode(WIFI_STA);
  WiFi.setHostname("monkey-deterrent");
  WiFi.begin(stationSsid.c_str(), stationPassword.c_str());
  Serial.print("Connecting to saved local Wi-Fi");
  uint32_t started = millis();
  while (WiFi.status() != WL_CONNECTED && millis() - started < 20000UL) {
    delay(250);
    Serial.print('.');
  }
  Serial.println();
  return WiFi.status() == WL_CONNECTED;
}

void setupNetwork() {
  preferences.begin("deterrent", true);
  stationSsid = preferences.getString("ssid", "");
  stationPassword = preferences.getString("password", "");
  preferences.end();

  if (stationSsid.length() == 0 || !connectToLocalWifi()) {
    Serial.println("No usable saved Wi-Fi; starting local setup hotspot.");
    startSetupAccessPoint();
    return;
  }

  if (MDNS.begin("monkey-deterrent")) {
    MDNS.addService("http", "tcp", 80);
  }
  server.on("/", HTTP_GET, []() {
    server.send(200, "text/plain", "Garden deterrent is online. POST /trigger with key=...; GET /status.");
  });
  server.on("/trigger", HTTP_POST, handleTrigger);
  server.on("/status", HTTP_GET, handleStatus);
  server.begin();
  Serial.print("Local network IP: ");
  Serial.println(WiFi.localIP());
}

void setup() {
  Serial.begin(115200);
  pinMode(TEST_BUTTON_PIN, INPUT_PULLUP);
  randomSeed(esp_random());

  dfSerial.begin(9600, SERIAL_8N1, DFPLAYER_RX_PIN, DFPLAYER_TX_PIN);
  if (player.begin(dfSerial, true, true)) {
    playerReady = true;
    player.volume(PLAYBACK_VOLUME);
    Serial.println("DFPlayer ready.");
  } else {
    Serial.println("DFPlayer not found; check its 5 V power, microSD card, and UART wires.");
  }
  setupNetwork();
}

void loop() {
  server.handleClient();

  bool pressed = digitalRead(TEST_BUTTON_PIN) == LOW;
  if (pressed && !wasButtonPressed) {
    if (playerReady && !cooldownActive()) {
      uint8_t track = random(FIRST_TRACK, LAST_TRACK + 1);
      player.playMp3Folder(track);
      lastTriggerMs = millis();
      Serial.printf("Manual test; playing /mp3/%04u.mp3\n", track);
    }
  }
  wasButtonPressed = pressed;
  delay(10);
}