# =======================================
# Control de riego automático extendido
# Raspberry Pi Pico - MicroPython + OLED
# Autor: CAHV (2025-08-16)
# =======================================

from machine import Pin, ADC, I2C
from time import sleep, ticks_ms
from ssd1306 import SSD1306_I2C

# --- Pines ---
sensor = ADC(Pin(26))     # GP26 = ADC0
relay = Pin(15, Pin.OUT)  # GP15 controla relay

# --- OLED I2C ---
# Conecta OLED: VCC=3.3V, GND=GND, SDA=GP4, SCL=GP5
WIDTH = 128
HEIGHT = 64
i2c = I2C(0, sda=Pin(4), scl=Pin(5), freq=400000)

print("Dispositivos I2C detectados:", [hex(addr) for addr in i2c.scan()])

oled = SSD1306_I2C(WIDTH, HEIGHT, i2c, addr=0x3C)
oled.fill(0)
oled.text("OLED lista!", 0, 0)
oled.show()

# --- Calibración del sensor ---
DRY_REF = 60000   # suelo seco
WET_REF = 30000   # suelo húmedo

# --- Umbrales de control ---
ON_THRESHOLD = 35   # Enciende bomba si humedad% < 35
HYSTERESIS = 7      # Apaga cuando suba por encima de 42
MIN_ON_TIME = 5000  # 5 segundos mínimo encendido

# --- Estado interno ---
pump_on = False
last_on_time = 0

print("Sistema de riego automático listo...")

def raw_to_percent(raw):
    """Convierte lectura cruda (0–65535) a % humedad según calibración."""
    raw = max(min(raw, DRY_REF), WET_REF)
    pct = int((DRY_REF - raw) * 100 / (DRY_REF - WET_REF))
    return max(0, min(100, pct))

def set_pump(state):
    """Enciende/apaga la bomba vía relay."""
    global pump_on, last_on_time
    if state and not pump_on:
        relay.value(1)
        pump_on = True
        last_on_time = ticks_ms()
        print("Bomba ENCENDIDA")
    elif not state and pump_on:
        relay.value(0)
        pump_on = False
        print("Bomba APAGADA")

def actualizar_oled(humedad, pump_on):
    """Muestra datos en pantalla OLED"""
    oled.fill(0)  # limpiar pantalla
    oled.text("Riego Automatico", 0, 0)
    oled.text(f"Humedad: {humedad:3d}%", 0, 20)
    estado = "BOMBA: ON " if pump_on else "BOMBA: OFF"
    oled.text(estado, 0, 40)
    oled.show()

while True:
    raw = sensor.read_u16()
    humedad = raw_to_percent(raw)
    off_threshold = ON_THRESHOLD + HYSTERESIS

    print(f"RAW={raw}  HUM%={humedad}  Pump={pump_on}")

    if not pump_on:
        if humedad < ON_THRESHOLD:
            set_pump(True)
    else:
        elapsed = ticks_ms() - last_on_time
        if humedad > off_threshold and elapsed >= MIN_ON_TIME:
            set_pump(False)

    # Actualizar OLED
    actualizar_oled(humedad, pump_on)

    sleep(1)