/*# =============================================================================
# UNIVERSIDAD INTERNACIONAL DE LA RIOJA (UNIR) - MAESTRÍA INDUSTRIA 4.0
# Autor: [Henry] - Versión: 10.1 Final - Fecha: [29/10/2025]
# =============================================================================*/


// ============ INCLUSIÓN DE BIBLIOTECAS ============
#include <Adafruit_Sensor.h> // Framework base de sensores Adafruit
#include <DHT.h>             // Driver específico para la familia de sensores DHT
#include <DHT_U.h>           // Capa de compatibilidad para el framework unificado (Unified)

// ============ CONFIGURACIÓN DE HARDWARE Y PINES ============
#define DHT_PIN 4               // GPIO4 para la línea de datos del sensor DHT22
#define TEMP_LED_PIN 14         // GPIO14 para indicador visual de alarma térmica
#define HUM_LED_PIN 15          // GPIO15 para indicador visual de alarma de humedad
#define TEMP_ACK_BUTTON_PIN 26  // GPIO26 para el pulsador de reconocimiento de temperatura
#define HUM_ACK_BUTTON_PIN 27   // GPIO27 para el pulsador de reconocimiento de humedad

// ============ UMBRALES Y PARÁMETROS DE OPERACIÓN ============
#define DHT_TYPE DHT22 // Define el modelo exacto de sensor utilizado

const float TEMP_ALARM_THRESHOLD = 45.0;      // Umbral térmico base para activación de alarma (°C)
const float HUM_ALARM_MIN_THRESHOLD = 25.0;   // Umbral mínimo de humedad para activación de alarma (%)
const float HUM_ALARM_MAX_THRESHOLD = 60.0;   // Umbral máximo de humedad para activación de alarma (%)

const float TEMP_HYSTERESIS = 1.0; // Margen de histéresis para temperatura (evita oscilaciones)
const float HUM_HYSTERESIS = 2.0;  // Margen de histéresis para humedad (evita oscilaciones)

const unsigned long SENSOR_READ_INTERVAL = 1000; // Intervalo entre lecturas del sensor (1000ms = 1s)
const unsigned long DEBOUNCE_DELAY = 200;         // Tiempo de anti-rebote para los pulsadores (200ms)

// ============ VARIABLES DE ESTADO GLOBALES ============
float current_temperature = 0.0;
float current_humidity = 0.0;
bool temp_alarm_active = false;
bool hum_alarm_active = false;
bool temp_alarm_acknowledged = false;
bool hum_alarm_acknowledged = false;
unsigned long last_sensor_read_time = 0;
unsigned long last_temp_button_time = 0;
unsigned long last_hum_button_time = 0;

// ============ INSTANCIAS DE OBJETOS ============
DHT_Unified dht(DHT_PIN, DHT_TYPE);

// ============ FUNCIÓN DE CONFIGURACIÓN PRINCIPAL (setup) ============
void setup() {
    Serial.begin(115200);
    Serial.println("Iniciando Sistema de Monitoreo Ambiental...");

    pinMode(TEMP_LED_PIN, OUTPUT);
    pinMode(HUM_LED_PIN, OUTPUT);
    digitalWrite(TEMP_LED_PIN, LOW);
    digitalWrite(HUM_LED_PIN, LOW);

    pinMode(TEMP_ACK_BUTTON_PIN, INPUT_PULLDOWN);
    pinMode(HUM_ACK_BUTTON_PIN, INPUT_PULLDOWN);

    dht.begin();
}

// ============ BUCLE DE EJECUCIÓN PRINCIPAL (loop) ============
void loop() {
    handle_sensor_readings();
    update_alarm_states();
    handle_acknowledge_buttons();
    update_led_indicators();
}

// ============ DEFINICIÓN DE FUNCIONES AUXILIARES ============

void handle_sensor_readings() {
    if (millis() - last_sensor_read_time >= SENSOR_READ_INTERVAL) {
        last_sensor_read_time = millis();
        sensors_event_t event;
        bool value_changed = false;

        dht.temperature().getEvent(&event);
        if (!isnan(event.temperature)) {
            if (event.temperature != current_temperature) {
                current_temperature = event.temperature;
                value_changed = true;
            }
        }
        dht.humidity().getEvent(&event);
        if (!isnan(event.relative_humidity)) {
            if (event.relative_humidity != current_humidity) {
                current_humidity = event.relative_humidity;
                value_changed = true;
            }
        }
        
        if (value_changed) {
            Serial.print("Cambio detectado -> ");
            Serial.print("Temperatura: ");
            Serial.print(current_temperature);
            Serial.print(" °C | Humedad: ");
            Serial.print(current_humidity);
            Serial.println(" %");
        }
    }
}

/**
 * @brief Evalúa las lecturas, actualiza el estado de las alarmas, y notifica
 * tanto la activación como la normalización de las condiciones.
 */
void update_alarm_states() {
    // --- Lógica de Temperatura ---
    const float temp_turn_off_threshold = TEMP_ALARM_THRESHOLD - TEMP_HYSTERESIS;
    if (!temp_alarm_active && current_temperature > TEMP_ALARM_THRESHOLD) {
        temp_alarm_active = true;
        Serial.println("*** ALARMA DE TEMPERATURA ACTIVADA ***");
    } else if (temp_alarm_active && current_temperature < temp_turn_off_threshold) {
        Serial.println("--- Condición de Temperatura Normalizada ---");
        temp_alarm_active = false;
        temp_alarm_acknowledged = false;
    }

    // --- Lógica de Humedad ---
    const float hum_turn_off_low_threshold = HUM_ALARM_MIN_THRESHOLD + HUM_HYSTERESIS;
    const float hum_turn_off_high_threshold = HUM_ALARM_MAX_THRESHOLD - HUM_HYSTERESIS;
    if (!hum_alarm_active && (current_humidity < HUM_ALARM_MIN_THRESHOLD || current_humidity > HUM_ALARM_MAX_THRESHOLD)) {
        hum_alarm_active = true;
        Serial.println("*** ALARMA DE HUMEDAD ACTIVADA ***");
    } else if (hum_alarm_active && (current_humidity > hum_turn_off_low_threshold && current_humidity < hum_turn_off_high_threshold)) {
        Serial.println("--- Condición de Humedad Normalizada ---");
        hum_alarm_active = false;
        hum_alarm_acknowledged = false;
    }
}

void handle_acknowledge_buttons() {
    if (digitalRead(TEMP_ACK_BUTTON_PIN) == HIGH) {
        if (millis() - last_temp_button_time > DEBOUNCE_DELAY) {
            if (temp_alarm_active) {
                temp_alarm_acknowledged = true;
                Serial.println("===> ALARMA DE TEMPERATURA RECONOCIDA <===");
            }
            last_temp_button_time = millis();
        }
    }

    if (digitalRead(HUM_ACK_BUTTON_PIN) == HIGH) {
        if (millis() - last_hum_button_time > DEBOUNCE_DELAY) {
            if (hum_alarm_active) {
                hum_alarm_acknowledged = true;
                Serial.println("===> ALARMA DE HUMEDAD RECONOCIDA <===");
            }
            last_hum_button_time = millis();
        }
    }
}

void update_led_indicators() {
    if (temp_alarm_active && !temp_alarm_acknowledged) {
        digitalWrite(TEMP_LED_PIN, HIGH);
    } else {
        digitalWrite(TEMP_LED_PIN, LOW);
    }

    if (hum_alarm_active && !hum_alarm_acknowledged) {
        digitalWrite(HUM_LED_PIN, HIGH);
    } else {
        digitalWrite(HUM_LED_PIN, LOW);
    }
}