# SPDX-License-Identifier: GPL-3.0-or-later
"""Structural validation tests for the shared Observation envelope.

These tests are STRUCTURAL ONLY — window ordering, confidence bounds, schema
version, round-trip serialization, extra-field rejection. Registry-aware
validation (unknown primitives, categorical-allowed-set, numeric-min-bound,
etc.) lives in each sibling package's own test_envelope.py because the
registry IS the sibling-specific concern.
"""

from __future__ import annotations

import pytest
from pydantic import ValidationError

from decnet_behave_core.spec import OBSERVATION_SCHEMA_VERSION, Observation, Window


def _make(primitive: str = "motor.example", value="x", **kwargs) -> Observation:
    base = dict(
        primitive=primitive,
        value=value,
        confidence=0.8,
        window=Window(start_ts=1.0, end_ts=2.0),
        source="test/sensor",
    )
    base.update(kwargs)
    return Observation(**base)


def test_minimal_observation_round_trips():
    obs = _make()
    obs2 = Observation.model_validate_json(obs.model_dump_json())
    assert obs == obs2


def test_schema_version_pinned_to_one():
    assert OBSERVATION_SCHEMA_VERSION == 1
    obs = _make()
    assert obs.v == 1


def test_window_end_must_be_after_start():
    with pytest.raises(ValidationError):
        Window(start_ts=2.0, end_ts=1.0)


def test_window_point_event_allowed():
    w = Window(start_ts=5.0, end_ts=5.0)
    assert w.start_ts == w.end_ts


def test_confidence_must_be_in_unit_interval():
    with pytest.raises(ValidationError):
        _make(confidence=-0.01)
    with pytest.raises(ValidationError):
        _make(confidence=1.01)


def test_extra_fields_forbidden():
    with pytest.raises(ValidationError):
        Observation(
            primitive="motor.example",
            value="x",
            confidence=0.5,
            window=Window(start_ts=1.0, end_ts=2.0),
            source="test/sensor",
            unknown_field="oops",
        )


def test_id_and_ts_auto_default():
    obs1 = _make()
    obs2 = _make()
    assert obs1.id != obs2.id
    assert obs1.ts > 0


def test_core_envelope_is_registry_agnostic():
    """The base Observation accepts any primitive string; sibling subclasses validate."""
    obs = _make(primitive="anything.goes.here", value="anything")
    assert obs.primitive == "anything.goes.here"
    assert obs.value == "anything"


def test_source_must_be_nonempty():
    with pytest.raises(ValidationError):
        _make(source="")