import importlib.util
import logging
from pathlib import Path
from poller.sources.base import Source, Reading

# Import api_renpho directly — bypasses their __init__.py which pulls in HA dependencies.
# We load const.py first (api_renpho imports from it), then api_renpho itself.
_renpho = Path(__file__).resolve().parents[2] / "integrations" / "hass_renpho" / "custom_components" / "renpho"

def _load_module(name, path):
    spec = importlib.util.spec_from_file_location(name, path)
    mod = importlib.util.module_from_spec(spec)
    import sys
    sys.modules[name] = mod
    spec.loader.exec_module(mod)
    return mod

_load_module("renpho.const", _renpho / "const.py")
_load_module("renpho.api_object", _renpho / "api_object.py")
_api = _load_module("renpho.api_renpho", _renpho / "api_renpho.py")
RenphoWeight = _api.RenphoWeight

log = logging.getLogger(__name__)

# Metrics to extract from MeasurementDetail and their units.
# key = field name on MeasurementDetail, value = (metric_name, unit)
METRICS = {
    "weight":    ("weight",       "kg"),
    "bmi":       ("bmi",          ""),
    "bodyfat":   ("body_fat",     "%"),
    "water":     ("body_water",   "%"),
    "muscle":    ("muscle_mass",  "kg"),
    "bone":      ("bone_mass",    "kg"),
    "subfat":    ("subcutaneous_fat", "%"),
    "visfat":    ("visceral_fat", ""),
    "bmr":       ("bmr",          "kcal"),
    "protein":   ("protein",      "%"),
    "bodyage":   ("body_age",     "years"),
    "heart_rate": ("heart_rate",  "bpm"),
    "fat_free_weight": ("fat_free_weight", "kg"),
}


class RenphoSource(Source):
    def __init__(self, email: str, password: str, user_id: str | None = None):
        self.client = RenphoWeight(email=email, password=password, user_id=user_id)

    async def fetch(self) -> list[Reading]:
        await self.client.auth()
        await self.client.get_scale_users()
        await self.client.get_measurements()

        readings = []
        for m in self.client.weight_history:
            ts = m.time_stamp
            uid = str(m.b_user_id)
            for field, (metric, unit) in METRICS.items():
                val = getattr(m, field, None)
                if val is not None and val != 0:
                    readings.append(Reading(
                        source_type="renpho",
                        source_user_id=uid,
                        metric=metric,
                        value=float(val),
                        unit=unit,
                        timestamp=ts,
                    ))
        log.info(f"renpho: fetched {len(self.client.weight_history)} measurements, {len(readings)} readings")
        return readings