/*
  Seeeduino XIAO ESP32-S3 + BMP280 -> WiFi -> UDP sender
  --------------------------------------------------------
  Reads temperature (°C) and pressure (hPa) from a BMP280 over I2C,
  along with the WiFi signal strength (RSSI), and sends them as a
  semicolon-delimited string (terminated with a newline) over UDP
  to a specified IP address and port 9999.
  Payload format: temperature;pressure;rssi\n
  Example:        24.53;1013.25;-58

  Wiring (I2C):
    XIAO ESP32-S3 SDA (D4/GPIO5)  -> BMP280 SDA
    XIAO ESP32-S3 SCL (D5/GPIO6)  -> BMP280 SCL
    3V3                           -> VCC
    GND                           -> GND

  Required libraries (install via Library Manager):
    - Adafruit BMP280 Library
    - Adafruit Unified Sensor
*/

#include <Wire.h>
#include <WiFi.h>
#include <WiFiUdp.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BMP280.h>

// ---------------- USER CONFIG ----------------
const char* WIFI_SSID     = "control-tower-24";
const char* WIFI_PASSWORD = "expaexpa";

// Destination for UDP packets
const char* UDP_TARGET_IP = "192.168.1.17";  // <-- change to your receiver's IP
const uint16_t UDP_TARGET_PORT = 9999;

// How often to read + send (ms)
const unsigned long SEND_INTERVAL_MS = 500;

// I2C pins for XIAO ESP32-S3 (default Wire pins)
const int I2C_SDA_PIN = 5;  // D4
const int I2C_SCL_PIN = 6;  // D5

// BMP280 I2C address: 0x76 (SDO to GND) or 0x77 (SDO to VCC)
const uint8_t BMP280_I2C_ADDRESS = 0x76;
// -----------------------------------------------

Adafruit_BMP280 bmp;
WiFiUDP udp;

unsigned long lastSendTime = 0;

void connectWiFi() {
  Serial.print("Connecting to WiFi");
  WiFi.mode(WIFI_STA);
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);

  while (WiFi.status() != WL_CONNECTED) {
    delay(400);
    Serial.print(".");
  }

  Serial.println();
  Serial.print("WiFi connected. IP address: ");
  Serial.println(WiFi.localIP());
}

void setup() {
  Serial.begin(115200);
  delay(1000); // give the serial monitor time to attach

  // Init I2C on XIAO ESP32-S3 pins
  Wire.begin(I2C_SDA_PIN, I2C_SCL_PIN);

  // Init BMP280
  if (!bmp.begin(BMP280_I2C_ADDRESS)) {
    Serial.println("Could not find a valid BMP280 sensor, check wiring or address!");
    while (1) {
      delay(1000);
    }
  }

  // Recommended settings for weather monitoring (see Adafruit example)
  bmp.setSampling(Adafruit_BMP280::MODE_NORMAL,
                  Adafruit_BMP280::SAMPLING_X2,   // temperature
                  Adafruit_BMP280::SAMPLING_X16,  // pressure
                  Adafruit_BMP280::FILTER_X16,
                  Adafruit_BMP280::STANDBY_MS_500);

  connectWiFi();
}

  long counter = 0;

void loop() {
  // Reconnect WiFi if dropped
  if (WiFi.status() != WL_CONNECTED) {
    connectWiFi();
  }

  unsigned long now = millis();
  if (now - lastSendTime >= SEND_INTERVAL_MS) {
    lastSendTime = now;

    float temperature = bmp.readTemperature();      // °C
    float pressure     = bmp.readPressure() / 100.0F; // Pa -> hPa
    long  rssi         = WiFi.RSSI();                 // dBm

    // Build payload: counter;temperature;pressure;rssi\n
    char payload[64];
    snprintf(payload, sizeof(payload), "%ld;%.2f;%.2f;%ld\n", counter, temperature, pressure, rssi);

    counter = counter + 1;

    Serial.print("Sending UDP packet: ");
    Serial.println(payload);

    udp.beginPacket(UDP_TARGET_IP, UDP_TARGET_PORT);
    udp.print(payload);
    udp.endPacket();
  }
}