#include <WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>

#define WIFI_SSID "Wokwi-GUEST"
#define WIFI_PASSWORD ""
#define WIFI_CHANNEL 6

const char *MQTT_BROKER_ADRESS = "broker.mqtt.cool";
const uint16_t MQTT_PORT = 1883;
const char *MQTT_CLIENT_NAME = "nazalopez";
const char *MQTT_USER = "a";
const char *MQTT_PASS = "b";

#define buttonA 35
#define buttonB 33
#define buttonC 14

#define ledAzul 22
#define ledVerde 19
#define ledNaranja 18

#define DESARMADA 0
#define ARMADA 1
#define FUNCIONAMIENTO 2
#define ALERTA 3

int state = DESARMADA;

volatile bool buttonA_released = false;
volatile bool buttonB_released = false;
volatile bool buttonC_released = false;
volatile bool timerBlink_interrupted = false;
volatile bool alertaActivada = false;

TaskHandle_t HandleTask1;
hw_timer_t *timerBlink = NULL;

WiFiClient espClient;
PubSubClient mqttClient(espClient);

/* ================= WIFI ================= */

void ConnectWiFi() {
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD, WIFI_CHANNEL);
  Serial.print("Connecting to WiFi");
  while (WiFi.status() != WL_CONNECTED) {
    delay(100);
    Serial.print(".");
  }
  Serial.println(" Connected!");
}

/* ================= MQTT ================= */

void OnMqttReceived(char *topic, byte *payload, unsigned int length) {
  String message = "";
  for (unsigned int i = 0; i < length; i++) {
    message += (char)payload[i];
  }

  Serial.print("MQTT [");
  Serial.print(topic);
  Serial.print("] -> ");
  Serial.println(message);

  if (strcmp(topic, "interfaz/input") == 0) {
    if (message == "A") {
      buttonA_released = true;
    } else if (message == "B") {
      buttonB_released = true;
    } else if (message == "C") {
      buttonC_released = true;
    } else {
      Serial.println("Payload incorrecto");
    }
  }

  else if (strcmp(topic, "interfaz/alerta") == 0) {
    if (message == "ON") {
      alertaActivada = true;
    } else if (message == "OFF") {
      alertaActivada = false;
    }
  }
}

void InitMqtt() {
  mqttClient.setServer(MQTT_BROKER_ADRESS, MQTT_PORT);
  mqttClient.setCallback(OnMqttReceived);
}

void ConnectMqtt() {
  while (!mqttClient.connected()) {
    Serial.print("Connecting to MQTT...");
    if (mqttClient.connect(MQTT_CLIENT_NAME, MQTT_USER, MQTT_PASS)) {
      mqttClient.subscribe("interfaz/input");
      mqttClient.subscribe("interfaz/alerta");
      Serial.println(" OK");
    } else {
      Serial.print(" failed, rc=");
      Serial.println(mqttClient.state());
      delay(2000);
    }
  }
}

void HandleMqtt() {
  if (!mqttClient.connected()) {
    ConnectMqtt();
  }
  mqttClient.loop();
}

/* ================= ISR ================= */

void IRAM_ATTR timerBlink_int() {
  timerBlink_interrupted = true;
}

void IRAM_ATTR buttonA_ISR() {
  buttonA_released = true;
}

void IRAM_ATTR buttonB_ISR() {
  buttonB_released = true;
}

void IRAM_ATTR buttonC_ISR() {
  buttonC_released = true;
}

/* ================= FSM ================= */

void FSM(void *parameter) {
  while (true) {

    HandleMqtt();   // 🔥 MQTT siempre activo

    switch (state) {

      case DESARMADA:
        if (buttonA_released) {
          buttonA_released = false;
          state = ARMADA;
          timerStop(timerBlink);
          digitalWrite(ledAzul, HIGH);
        }

        if (timerBlink_interrupted) {
          timerBlink_interrupted = false;
          digitalWrite(ledAzul, !digitalRead(ledAzul));
        }

        if (alertaActivada) {
          state = ALERTA;
          timerStart(timerBlink);
        }
        break;

      case ARMADA:
        if (buttonB_released) {
          buttonB_released = false;
          state = FUNCIONAMIENTO;
          digitalWrite(ledVerde, HIGH);
          digitalWrite(ledAzul, LOW);
        }

        if (buttonA_released) {
          buttonA_released = false;
          state = DESARMADA;
          timerStart(timerBlink);
        }

        if (alertaActivada) {
          state = ALERTA;
          timerStart(timerBlink);
        }
        break;

      case FUNCIONAMIENTO:
        if (buttonB_released) {
          buttonB_released = false;
          state = ARMADA;
          digitalWrite(ledAzul, HIGH);
        }

        if (alertaActivada) {
          state = ALERTA;
          timerStart(timerBlink);
        }
        break;

      case ALERTA:
        if (buttonC_released) {
          buttonC_released = false;
          alertaActivada = false;
          state = DESARMADA;
        }

        if (timerBlink_interrupted) {
          timerBlink_interrupted = false;
          digitalWrite(ledAzul, !digitalRead(ledAzul));
          digitalWrite(ledNaranja, !digitalRead(ledNaranja));
        }
        break;
    }

    vTaskDelay(10 / portTICK_PERIOD_MS);
  }
}

/* ================= SETUP / LOOP ================= */

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

  ConnectWiFi();
  InitMqtt();

  pinMode(buttonA, INPUT_PULLUP);
  pinMode(buttonB, INPUT_PULLUP);
  pinMode(buttonC, INPUT_PULLUP);

  pinMode(ledAzul, OUTPUT);
  pinMode(ledVerde, OUTPUT);
  pinMode(ledNaranja, OUTPUT);

  attachInterrupt(digitalPinToInterrupt(buttonA), buttonA_ISR, FALLING);
  attachInterrupt(digitalPinToInterrupt(buttonB), buttonB_ISR, FALLING);
  attachInterrupt(digitalPinToInterrupt(buttonC), buttonC_ISR, FALLING);

  timerBlink = timerBegin(1000000);
  timerAttachInterrupt(timerBlink, &timerBlink_int);
  timerAlarm(timerBlink, 250000, true, 0);
  timerStart(timerBlink);

  xTaskCreatePinnedToCore(
    FSM,
    "FSM",
    4096,
    NULL,
    1,
    &HandleTask1,
    0
  );
}

void loop() {
  delay(10);
}