# HaemoHelper — iBX020 Fault Monitor
# Main firmware for Raspberry Pi Pico 2W
# MicroPython

import time
import network
import machine
from machine import I2C, Pin

from config import (
    WIFI_SSID, WIFI_PASSWORD,
    I2C_SDA, I2C_SCL, I2C_FREQ,
    ADS1115_U3, ADS1115_U4,
    GPIO_DI, GPIO_T,
    DIVIDER_RATIO,
    CURRENT_ZERO_VOLTAGE, CURRENT_SENSITIVITY,
    SAMPLE_INTERVAL_MS
)
from ads1115 import ADS1115
from di_decoder import DIDecoder
from logger import Logger
from webserver import WebServer

# ─── Boot indicator ───────────────────────────────────────────────
led = Pin("LED", Pin.OUT)
def blink(n, ms=100):
    for _ in range(n):
        led.on(); time.sleep_ms(ms); led.off(); time.sleep_ms(ms)

print("\n╔══════════════════════════════╗")
print("║   HaemoHelper v1.0           ║")
print("║   iBX020 Fault Monitor       ║")
print("╚══════════════════════════════╝\n")
blink(3)

# ─── WiFi ─────────────────────────────────────────────────────────
print(f"Connecting to WiFi: {WIFI_SSID}")
wlan = network.WLAN(network.STA_IF)
wlan.active(True)
wlan.connect(WIFI_SSID, WIFI_PASSWORD)

timeout = 20
while not wlan.isconnected() and timeout > 0:
    led.toggle()
    time.sleep(0.5)
    timeout -= 1
    print(".", end="")

print()
if wlan.isconnected():
    ip = wlan.ifconfig()[0]
    print(f"Connected. IP: {ip}")
    print(f"Dashboard: http://{ip}")
    blink(5, 50)
    led.on()
else:
    print("WiFi failed — continuing without network")
    blink(10, 50)

# ─── I2C and ADC setup ────────────────────────────────────────────
print("\nInitialising I2C and ADC modules...")
i2c = I2C(0, sda=Pin(I2C_SDA), scl=Pin(I2C_SCL), freq=I2C_FREQ)

# Scan I2C bus
devices = i2c.scan()
print(f"I2C devices found: {[hex(d) for d in devices]}")

if ADS1115_U3 not in devices:
    print(f"WARNING: ADS1115 U3 (0x{ADS1115_U3:02x}) not found on I2C bus")
if ADS1115_U4 not in devices:
    print(f"WARNING: ADS1115 U4 (0x{ADS1115_U4:02x}) not found on I2C bus")

adc_u3 = ADS1115(i2c, ADS1115_U3)  # Voltage dividers
adc_u4 = ADS1115(i2c, ADS1115_U4)  # Current sensor

# ─── GPIO setup ───────────────────────────────────────────────────
pin_di = Pin(GPIO_DI, Pin.IN, Pin.PULL_DOWN)
pin_t  = Pin(GPIO_T,  Pin.IN, Pin.PULL_DOWN)
print(f"GPIO ready — D/I on GP{GPIO_DI}, T on GP{GPIO_T}")

# ─── Modules ──────────────────────────────────────────────────────
logger     = Logger()
di_decoder = DIDecoder()
server     = WebServer(logger, di_decoder)
server.start()

print("\nAll systems ready. Logging started.\n")

# ─── Timestamp helper ─────────────────────────────────────────────
def timestamp():
    t = time.localtime()
    return f"{t[0]:04d}-{t[1]:02d}-{t[2]:02d} {t[3]:02d}:{t[4]:02d}:{t[5]:02d}"

# ─── Voltage scaling ──────────────────────────────────────────────
def adc_to_fridge_voltage(adc_voltage):
    """Convert scaled ADC voltage back to original fridge circuit voltage"""
    if DIVIDER_RATIO == 0:
        return 0.0
    return adc_voltage / DIVIDER_RATIO

def adc_to_current(adc_voltage):
    """Convert HSTS016L output voltage to amps"""
    return (adc_voltage - CURRENT_ZERO_VOLTAGE) / CURRENT_SENSITIVITY

# ─── Main loop ────────────────────────────────────────────────────
last_sample_ms = 0
last_di_event_code = None

print("timestamp,psu_v,fan_v,ssr_v,ctrl_v,current_a,t_state,di_state,di_code")

while True:
    now_ms = time.ticks_ms()

    # ── Sample all channels at 1Hz ──────────────────────────────
    if time.ticks_diff(now_ms, last_sample_ms) >= SAMPLE_INTERVAL_MS:
        last_sample_ms = now_ms
        ts = timestamp()

        # Read voltage channels from U3
        psu_v  = adc_to_fridge_voltage(adc_u3.read_voltage(0))
        fan_v  = adc_to_fridge_voltage(adc_u3.read_voltage(1))
        ssr_v  = adc_to_fridge_voltage(adc_u3.read_voltage(2))
        ctrl_v = adc_to_fridge_voltage(adc_u3.read_voltage(3))

        # Read current from U4
        current_raw = adc_u4.read_voltage(0)
        current_a   = adc_to_current(current_raw)

        # Read digital inputs
        t_state  = pin_t.value()
        di_state = pin_di.value()

        # Update D/I decoder
        di_code = di_decoder.update(di_state, now_ms)

        # Log D/I fault event if new code detected
        if di_code is not None and di_code != last_di_event_code:
            desc = di_decoder.describe(di_code)
            logger.log_event(ts, f"D/I fault code {di_code}: {desc}")
            last_di_event_code = di_code

        # Write to log
        logger.log_reading(ts, psu_v, fan_v, ssr_v, ctrl_v,
                           current_a, t_state, di_state, di_code)

        # Print to serial for debugging
        print(f"{ts},{psu_v:.2f},{fan_v:.2f},{ssr_v:.2f},{ctrl_v:.2f},"
              f"{current_a:.3f},{t_state},{di_state},"
              f"{di_code if di_code is not None else ''}")

    # ── Serve web requests (non-blocking) ───────────────────────
    server.serve()

    # Small sleep to avoid busy loop hammering the CPU
    time.sleep_ms(10)