#include <WiFi.h>
#include <esp_now.h>
#include <Adafruit_NeoPixel.h>

// --- NeoPixel-Definition ---
#define LED_PIN    1      // D1 = GPIO1
#define NUM_LEDS  40
Adafruit_NeoPixel strip(NUM_LEDS, LED_PIN, NEO_GRB + NEO_KHZ800);

// --- Sensor-Definition ---
#define MQ135_PIN  A0

// --- ESP-NOW-Peer-MAC (Empfänger) ---
uint8_t peerMAC[] = { 0xE4, 0xB0, 0x63, 0x41, 0xD1, 0x18 };

// --- Status-Codes ---
// 0 = Kalibrieren, 1 = gut, 2 = okay, 3 = schlecht
uint8_t state     = 0;
uint32_t baseAvg  = 0;   // Basiswert aus Kalibrierung
uint8_t failCount = 0;
uint16_t spinnerPos = 0;

// Callback: Sendestatus -> failCount
void onDataSent(const uint8_t *mac_addr, esp_now_send_status_t status) {
  if (status == ESP_NOW_SEND_SUCCESS) {
    failCount = 0;
  } else {
    failCount++;
  }
}

// „Breathing“ in Weiß (gesamte Dauer in ms)
void breatheWhite(uint16_t durationMs) {
  const int steps    = 50;
  const int halfMs   = durationMs / 2;
  const int delayMs  = halfMs / steps;
  // fade up
  for (int i = 0; i <= steps; i++) {
    strip.setBrightness(map(i, 0, steps, 0, 255));
    strip.fill(strip.Color(255,255,255), 0, NUM_LEDS);
    strip.show();
    delay(delayMs);
  }
  // fade down
  for (int i = steps; i >= 0; i--) {
    strip.setBrightness(map(i, 0, steps, 0, 255));
    strip.fill(strip.Color(255,255,255), 0, NUM_LEDS);
    strip.show();
    delay(delayMs);
  }
  strip.setBrightness(255);
}

// Spinner-Animation bei Verbindungsproblemen
void showSpinner() {
  strip.clear();
  for (uint8_t i = 0; i < 3; i++) {
    strip.setPixelColor((spinnerPos + i) % NUM_LEDS,
                        strip.Color(255,255,255));
  }
  strip.show();
  spinnerPos = (spinnerPos + 1) % NUM_LEDS;
  delay(100);
}

void setup() {
  Serial.begin(115200);

  // NeoPixel initialisieren + weißes Aufleuchten
  strip.begin();
  strip.fill(strip.Color(255,255,255), 0, NUM_LEDS);
  strip.setBrightness(255);
  strip.show();

  // WLAN & ESP-NOW init
  WiFi.mode(WIFI_STA);
  if (esp_now_init() != ESP_OK) {
    // Endlosschleife mit White-Flash
    while (true) {
      strip.fill(strip.Color(255,255,255), 0, NUM_LEDS);
      strip.show();
      delay(100);
      strip.clear();
      strip.show();
      delay(100);
    }
  }
  esp_now_register_send_cb(onDataSent);
  esp_now_peer_info_t peer = {};
  memcpy(peer.peer_addr, peerMAC, 6);
  peer.channel = 0; peer.encrypt = false;
  esp_now_add_peer(&peer);

  Serial.println("Starte Kalibrierung (60s)...");

  // Kalibrierung: 60 Messungen im 1s-Takt
  uint32_t sum = 0;
  for (int i = 0; i < 60; i++) {
    int raw = analogRead(MQ135_PIN);
    sum += raw;
    // Sende Kalibrierungs-Status
    state = 0;
    esp_now_send(peerMAC, &state, 1);
    // Weißes „Breathing“
    breatheWhite(1000);
  }
  baseAvg = sum / 60;
  Serial.printf("Kalibrierung fertig, Basis = %u\n", baseAvg);

  // LEDs aus nach Kalibrierung
  strip.clear();
  strip.show();
  delay(500);
}

void loop() {
  // 1) Sensor auslesen
  int raw = analogRead(MQ135_PIN);

  // 2) Klassifikation relativ zum Basiswert
  if      (raw <= baseAvg)         state = 1;  // gut
  else if (raw <= baseAvg * 1.2f)  state = 2;  // okay
  else                              state = 3;  // schlecht

  // 3) Status senden
  esp_now_send(peerMAC, &state, 1);

  // 4) Animation / Farblegende
  if (failCount >= 10) {
    showSpinner();
  } else {
    strip.clear();
    switch (state) {
      case 1:  // gut → Grün jede zweite LED
        for (int i = 0; i < NUM_LEDS; i += 2)
          strip.setPixelColor(i, strip.Color(0,150,0));
        break;
      case 2:  // okay → Gelb
        for (int i = 0; i < NUM_LEDS; i += 2)
          strip.setPixelColor(i, strip.Color(150,150,0));
        break;
      case 3:  // schlecht → Rot
        for (int i = 0; i < NUM_LEDS; i += 2)
          strip.setPixelColor(i, strip.Color(150,0,0));
        break;
    }
    strip.show();
    delay(1000);
  }
}