import machine
from machine import Pin, ADC, PWM, I2C
from lcd_i2c import LCD
import time, math
import network
from umqtt.simple import MQTTClient
import ubinascii

# =========================
# Configuración WiFi
# =========================
SSID = "TuSSID"
PASS = "TuClave"

# =========================
# MQTT (HiveMQ Cloud / Adafruit IO)
# =========================
MQTT_BROKER = "broker.hivemq.com"   # o el broker que uses
MQTT_PORT = 8883                     # puerto TLS
MQTT_USER = ""                       # si aplica
MQTT_PASS = ""                       # si aplica
CLIENT_ID = ubinascii.hexlify(machine.unique_id())

TOPIC_PUBLISH = b"freecooling/status"
TOPIC_SUBSCRIBE = b"freecooling/cmd"

USER_PASSWORD = "1234"  # clave de usuario para cambiar persiana

# =========================
# Hardware
# =========================
adc_int = ADC(Pin(34))
adc_int.atten(ADC.ATTN_11DB)
adc_int.width(ADC.WIDTH_12BIT)

adc_ext = ADC(Pin(35))
adc_ext.atten(ADC.ATTN_11DB)
adc_ext.width(ADC.WIDTH_12BIT)

servo = PWM(Pin(23), freq=50)

sda = Pin(21, Pin.OUT)
scl = Pin(22, Pin.OUT)
i2c = I2C(0, sda=sda, scl=scl, freq=400000)
lcd_addr = i2c.scan()[0]
lcd = LCD(addr=lcd_addr, cols=16, rows=2, i2c=i2c)
lcd.begin()

boton_modo = Pin(18, Pin.IN, Pin.PULL_UP)

# =========================
# Parámetros
# =========================
T_MIN = 22.0
T_MAX = 24.0
HYST = 0.5
BETA = 3950
R0 = 10000
T0 = 298.15

DUTY_MIN = int(65535 * 0.025)
DUTY_MAX = int(65535 * 0.128)

modo_manual = False
manual_pos = 0
apertura = 0

# =========================
# Funciones
# =========================
def ntc_to_temp(adc_val, r_series=10000):
    if adc_val <= 0:
        return 0
    v = adc_val / 4095.0 * 3.3
    r_ntc = r_series * v / (3.3 - v)
    t = 1.0 / (1.0/T0 + (1.0/BETA) * math.log(r_ntc/R0)) - 273.15
    return t

def set_servo(percent):
    duty = DUTY_MIN + int((DUTY_MAX - DUTY_MIN) * percent / 100)
    servo.duty_u16(duty)

def mostrar_en_lcd(linea1, linea2=""):
    lcd.clear()
    lcd.print(linea1[:16])
    lcd.set_cursor(0,1)
    lcd.print(linea2[:16])

def decidir_apertura(t_int, t_ext, apertura_prev):
    apertura = apertura_prev
    if t_int < T_MIN - HYST:
        apertura = 0
    elif t_int > T_MAX + HYST and t_ext >= t_int:
        apertura = 0
    elif t_int > T_MIN:
        delta = t_int - t_ext
        if delta > 0:
            apertura = int((delta / 8.0) * 100)
            apertura = max(0, min(apertura, 100))
    apertura = round(apertura / 10) * 10
    return apertura

# =========================
# Callback MQTT
# =========================
def mqtt_callback(topic, msg):
    global apertura
    try:
        payload = msg.decode()
        # Espera formato "clave:pos" ej "1234:50"
        if ":" in payload:
            clave, pos = payload.split(":")
            if clave == USER_PASSWORD:
                pos = int(pos)
                pos = max(0, min(pos, 100))
                apertura = pos
                set_servo(apertura)
    except Exception as e:
        print("Error MQTT:", e)

# =========================
# Conexión WiFi
# =========================
wifi = network.WLAN(network.STA_IF)
wifi.active(True)
wifi.connect(SSID, PASS)
while not wifi.isconnected():
    time.sleep(0.5)
ip = wifi.ifconfig()[0]
print("Conectado en", ip)
mostrar_en_lcd("WiFi Conectado", ip)

# =========================
# Cliente MQTT
# =========================
client = MQTTClient(CLIENT_ID, MQTT_BROKER, port=MQTT_PORT, user=MQTT_USER, password=MQTT_PASS, ssl=True)
client.set_callback(mqtt_callback)
client.connect()
client.subscribe(TOPIC_SUBSCRIBE)

# =========================
# Bucle principal
# =========================
set_servo(apertura)

while True:
    t_int = ntc_to_temp(adc_int.read())
    t_ext = ntc_to_temp(adc_ext.read())

    # Botón modo manual
    if boton_modo.value() == 0:
        time.sleep_ms(300)
        if boton_modo.value() == 0:
            if not modo_manual:
                modo_manual = True
                manual_pos = 0
            else:
                manual_pos += 50
                if manual_pos > 100:
                    modo_manual = False
            time.sleep(1)

    if modo_manual:
        apertura = manual_pos
        set_servo(apertura)
        linea1 = "MODO MANUAL"
        linea2 = "Persiana:{}%".format(apertura)
    else:
        nueva_apertura = decidir_apertura(t_int, t_ext, apertura)
        if nueva_apertura != apertura:
            apertura = nueva_apertura
            set_servo(apertura)
        linea1 = "Int:{:.1f} Ext:{:.1f}".format(t_int, t_ext)
        linea2 = "Auto:{}%".format(apertura)

    mostrar_en_lcd(linea1, linea2)

    # Publicar estado en MQTT
    msg = "Int:{:.1f},Ext:{:.1f},Persiana:{}".format(t_int, t_ext, apertura)
    try:
        client.publish(TOPIC_PUBLISH, msg)
        client.check_msg()  # revisa si hay mensaje entrante
    except:
        pass

    time.sleep(2)