"""Forecast family fault isolation; no IO, fabricated samples or model switching."""
from collections.abc import Mapping
from math import isfinite
from numbers import Real


def collect_predictions(data, config, models, enabled):
    """Return complete finite PV/load series independently for each requested model.

    A model with insufficient history must not prevent other valid families being
    published. It is omitted, not filled with zeros or replaced by another model.
    Global raw-telemetry checks still run BEFORE this helper in run_forecast.
    """
    expected = tuple(data['df_fut'].index)
    if not expected or len(set(expected)) != len(expected):
        raise ValueError('Nonempty unique future interval index required')
    expected_keys = set(expected)
    predictions, errors = {}, {}
    requested = 0
    for variant, model in models.items():
        predictions[variant] = {}
        if not enabled(config, variant):
            continue
        requested += 1
        try:
            values = model.predict(data)
            if not isinstance(values, Mapping) or set(values) != expected_keys:
                raise ValueError('Missing, extra or non-matching forecast timestamps')
            cleaned = {}
            for at in expected:
                value = values[at]
                if isinstance(value, bool) or not isinstance(value, Real):
                    raise ValueError('Non-numeric forecast power')
                value = float(value)
                if not isfinite(value) or value < 0:
                    raise ValueError('Invalid nonnegative forecast power')
                cleaned[at] = value
            predictions[variant] = cleaned
        except Exception as error:
            # Expected data failures and unexpected model failures are visible,
            # but model exception text may contain filesystem paths. Do not leak it.
            errors[variant] = {'status': 'unavailable', 'errorType': type(error).__name__}
    if requested and all(not p for p in predictions.values()):
        raise ValueError('All requested PV/load models failed; no forecasts published')
    return predictions, errors