"""Tests for M5-T09: exposed_entities table + ExposableEntity/provider framework.

Covers:
  1. ExposableEntity dataclass: fields, key stability.
  2. Provider registry: register_provider, get_providers.
  3. build_catalog: entity enumeration, device grouping, metadata from profile,
     toggle defaults (enabled=False), binary_sensor presence.
  4. Migration shape: upgrade creates the table + unique index; downgrade drops it.
  5. ORM round-trip: toggle insert/read/update; default enabled=False.
  6. APP_BASELINE_REVISION matches the new Alembic head.
"""

from __future__ import annotations

from datetime import datetime, timezone
from pathlib import Path
from typing import TYPE_CHECKING
import pytest
from alembic import command
from alembic.config import Config
from sqlalchemy import create_engine, inspect
from sqlalchemy.orm import Session

if TYPE_CHECKING:
    pass


# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------


def _make_app_alembic_config(database_url: str) -> Config:
    cfg = Config("alembic_app.ini")
    cfg.set_main_option("sqlalchemy.url", database_url)
    return cfg


def _make_modbus_device(session: Session, *, friendly_name: str, uuid: str) -> object:
    """Insert a ModbusDevice row into a test DB session and return it."""
    from datetime import datetime, timezone

    from app.models.modbus import ModbusDevice

    now = datetime.now(tz=timezone.utc)
    device = ModbusDevice(
        uuid=uuid,
        friendly_name=friendly_name,
        host="192.168.1.1",
        port=502,
        unit_id=1,
        profile="sdm120",
        poll_interval_s=5,
        enabled=True,
        created_at=now,
        updated_at=now,
    )
    session.add(device)
    session.flush()
    return device


# ---------------------------------------------------------------------------
# Fixtures
# ---------------------------------------------------------------------------


@pytest.fixture()
def expose_db(tmp_path: Path):
    """Temporary SQLite DB upgraded to the current Alembic head (includes new toggle table)."""
    db_path = tmp_path / "expose_test.db"
    db_url = f"sqlite:///{db_path}"
    alembic_cfg = _make_app_alembic_config(db_url)
    command.upgrade(alembic_cfg, "head")
    engine = create_engine(db_url, connect_args={"check_same_thread": False})
    yield engine
    engine.dispose()


# ---------------------------------------------------------------------------
# 1. ExposableEntity / DeviceInfo dataclass tests
# ---------------------------------------------------------------------------


def test_exposable_entity_fields():
    """ExposableEntity must have all required fields with correct defaults."""
    from app.integrations.expose import DeviceInfo, ExposableEntity

    device = DeviceInfo(identifiers=("modbus", "abc-uuid"), name="Test Device")
    entity = ExposableEntity(
        key="modbus.abc-uuid.voltage",
        component="sensor",
        device=device,
        device_class="voltage",
        unit="V",
        name="Test Device Voltage",
    )

    assert entity.key == "modbus.abc-uuid.voltage"
    assert entity.component == "sensor"
    assert entity.device.identifiers == ("modbus", "abc-uuid")
    assert entity.device.name == "Test Device"
    assert entity.device_class == "voltage"
    assert entity.unit == "V"
    assert entity.name == "Test Device Voltage"
    assert entity.value_getter is None  # default
    assert entity.state_class is None  # default


def test_exposable_entity_with_value_getter():
    """ExposableEntity.value_getter stores and calls the provided callable.

    value_getter now accepts a Session argument (updated in T11-rework-1).
    """
    from app.integrations.expose import DeviceInfo, ExposableEntity
    from sqlalchemy import create_engine
    from sqlalchemy.orm import Session

    device = DeviceInfo(identifiers=("modbus", "dev1"), name="D1")
    # The value_getter receives a Session; use a lambda that ignores it.
    getter = lambda _sess: 230.5  # noqa: E731
    entity = ExposableEntity(
        key="modbus.dev1.voltage",
        component="sensor",
        device=device,
        device_class="voltage",
        unit="V",
        name="D1 Voltage",
        value_getter=getter,
    )
    assert entity.value_getter is not None
    eng = create_engine("sqlite:///:memory:")
    with Session(eng) as session:
        assert entity.value_getter(session) == 230.5


def test_entity_key_stability_uses_uuid_not_id():
    """Keys must be derived from uuid (stable), never from auto-increment DB ids."""
    from app.integrations.expose import DeviceInfo, ExposableEntity

    uuid_val = "550e8400-e29b-41d4-a716-446655440000"
    key = f"modbus.{uuid_val}.voltage"
    device = DeviceInfo(identifiers=("modbus", uuid_val), name="Stable Device")
    entity = ExposableEntity(
        key=key,
        component="sensor",
        device=device,
        device_class="voltage",
        unit="V",
        name="Stable Device Voltage",
    )
    # Key is uuid-based: it must not contain any integer-only segment that
    # looks like an auto-increment id (i.e., it contains the full uuid string).
    assert uuid_val in entity.key
    assert "modbus" in entity.key
    assert "voltage" in entity.key


# ---------------------------------------------------------------------------
# 2. Provider registry tests
# ---------------------------------------------------------------------------


def test_register_provider_as_decorator():
    """register_provider used as a decorator must add the callable to the registry."""
    from app.integrations.expose import get_providers, register_provider

    before = len(get_providers())

    @register_provider
    def _dummy_provider(session):
        return []

    after_providers = get_providers()
    assert len(after_providers) == before + 1
    assert _dummy_provider in after_providers

    # Clean up: remove the dummy from the module-level registry.
    from app.integrations import expose as _expose_mod
    _expose_mod._REGISTRY.remove(_dummy_provider)


def test_register_provider_direct_call():
    """register_provider called directly must also register the callable."""
    from app.integrations.expose import get_providers, register_provider
    from app.integrations import expose as _expose_mod

    def _another_dummy(session):
        return []

    before = len(get_providers())
    returned = register_provider(_another_dummy)
    assert returned is _another_dummy  # returns the provider unchanged
    assert len(get_providers()) == before + 1

    # Clean up.
    _expose_mod._REGISTRY.remove(_another_dummy)


# ---------------------------------------------------------------------------
# 3. build_catalog tests
# ---------------------------------------------------------------------------


def test_build_catalog_empty_with_no_devices(expose_db):
    """build_catalog with no enabled modbus devices must contain no modbus entities.

    The energy_cost provider is always registered and always produces its 6 entities
    (4 original + 2 daily) regardless of device state, so the catalog will not be empty.
    This test checks that no *modbus* entities are present when there are no enabled
    modbus devices.
    """
    from app.integrations.expose import build_catalog

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    # The modbus provider finds no enabled devices → no modbus entities.
    # The energy_cost provider always produces 6 entities, so the catalog is non-empty.
    modbus_entities = [e for e in catalog if e.entity.key.startswith("modbus.")]
    assert modbus_entities == [], (
        "Expected no modbus entities when no modbus devices are enabled"
    )

    # The 6 energy_cost entities should always be present (4 original + 2 daily).
    energy_keys = {e.entity.key for e in catalog if e.entity.key.startswith("energy.")}
    assert len(energy_keys) == 6, (
        f"Expected exactly 6 energy_cost entities (4 original + 2 daily), got {energy_keys!r}"
    )


def test_build_catalog_produces_entities_for_enabled_device(expose_db):
    """build_catalog must yield entities (including binary_sensor) for each enabled device."""
    from app.integrations.expose import build_catalog, CatalogEntry

    # Insert a test device.
    test_uuid = "aaaaaaaa-0000-0000-0000-000000000001"
    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 Test", uuid=test_uuid)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    assert len(catalog) > 0, "Expected at least one entity for the enabled device"

    keys = [entry.entity.key for entry in catalog]

    # Must contain a 'modbus.<uuid>.online' binary_sensor.
    online_key = f"modbus.{test_uuid}.online"
    assert online_key in keys, f"Expected online entity key {online_key!r} in catalog"

    # Must contain at least one sensor entity (voltage is always in sdm120 profile).
    voltage_key = f"modbus.{test_uuid}.voltage"
    assert voltage_key in keys, f"Expected voltage entity key {voltage_key!r} in catalog"

    # Verify CatalogEntry type.
    assert all(isinstance(e, CatalogEntry) for e in catalog)


def test_build_catalog_default_enabled_false(expose_db):
    """Entities with no toggle row must default to enabled=False."""
    from app.integrations.expose import build_catalog

    test_uuid = "aaaaaaaa-0000-0000-0000-000000000002"
    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 B", uuid=test_uuid)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    # No toggle rows inserted → all must be disabled.
    assert all(not entry.enabled for entry in catalog), (
        "All catalog entries must default to enabled=False when no toggle row exists"
    )


def test_build_catalog_respects_toggle_enabled(expose_db):
    """An entity with a toggle row enabled=True must appear as enabled in the catalog."""
    from datetime import datetime, timezone

    from app.integrations.expose import build_catalog
    from app.models.expose import ExposedEntityToggle

    test_uuid = "aaaaaaaa-0000-0000-0000-000000000003"
    voltage_key = f"modbus.{test_uuid}.voltage"

    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 C", uuid=test_uuid)
        # Enable the voltage entity explicitly.
        toggle = ExposedEntityToggle(
            key=voltage_key,
            enabled=True,
            updated_at=datetime.now(tz=timezone.utc),
        )
        session.add(toggle)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    enabled_keys = {entry.entity.key for entry in catalog if entry.enabled}
    assert voltage_key in enabled_keys, (
        f"Expected {voltage_key!r} to be enabled after toggling"
    )

    # Other entities (no toggle row) must still default to disabled.
    online_key = f"modbus.{test_uuid}.online"
    disabled_keys = {entry.entity.key for entry in catalog if not entry.enabled}
    assert online_key in disabled_keys, f"Expected {online_key!r} to remain disabled"


def test_build_catalog_device_grouping(expose_db):
    """All entities for a device must share the same DeviceInfo (device grouping)."""
    from app.integrations.expose import build_catalog

    test_uuid = "aaaaaaaa-0000-0000-0000-000000000004"
    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 D", uuid=test_uuid)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    device_entities = [e for e in catalog if test_uuid in e.entity.key]
    assert len(device_entities) > 0

    # All entities for this device must use the same device identifiers tuple.
    identifiers_set = {e.entity.device.identifiers for e in device_entities}
    assert len(identifiers_set) == 1, (
        "All entities for one device must share the same DeviceInfo identifiers"
    )
    assert identifiers_set.pop() == ("modbus", test_uuid)


def test_build_catalog_metric_metadata_from_profile(expose_db):
    """Entity device_class and unit must match the sdm120 profile's metrics."""
    from app.integrations.expose import build_catalog
    from app.integrations.modbus.profiles import load_profile

    test_uuid = "aaaaaaaa-0000-0000-0000-000000000005"
    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 E", uuid=test_uuid)
        session.commit()

    profile = load_profile("sdm120")
    metric_map = {m.key: m for m in profile.metrics}

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    sensor_entities = [
        e for e in catalog
        if e.entity.component == "sensor" and test_uuid in e.entity.key
    ]

    for entry in sensor_entities:
        # Extract metric key from entity key: "modbus.<uuid>.<metric_key>"
        _, _, metric_key = entry.entity.key.split(".", 2)
        if metric_key in metric_map:
            metric_spec = metric_map[metric_key]
            assert entry.entity.device_class == (metric_spec.device_class or None), (
                f"device_class mismatch for {metric_key!r}: "
                f"expected {metric_spec.device_class!r}, "
                f"got {entry.entity.device_class!r}"
            )
            assert entry.entity.unit == metric_spec.unit, (
                f"unit mismatch for {metric_key!r}: "
                f"expected {metric_spec.unit!r}, got {entry.entity.unit!r}"
            )
            assert entry.entity.component == metric_spec.ha_component, (
                f"component mismatch for {metric_key!r}: "
                f"expected {metric_spec.ha_component!r}, "
                f"got {entry.entity.component!r}"
            )


def test_build_catalog_online_binary_sensor_present(expose_db):
    """Each enabled device must produce exactly one binary_sensor 'online' entity."""
    from app.integrations.expose import build_catalog

    uuid1 = "aaaaaaaa-0000-0000-0000-000000000006"
    uuid2 = "aaaaaaaa-0000-0000-0000-000000000007"

    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="Device F1", uuid=uuid1)
        _make_modbus_device(session, friendly_name="Device F2", uuid=uuid2)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    binary_sensors = [e for e in catalog if e.entity.component == "binary_sensor"]
    binary_sensor_keys = {e.entity.key for e in binary_sensors}

    assert f"modbus.{uuid1}.online" in binary_sensor_keys
    assert f"modbus.{uuid2}.online" in binary_sensor_keys
    # No sensor must masquerade as binary_sensor and vice versa.
    assert all("online" in e.entity.key for e in binary_sensors), (
        "All binary_sensor entities should be 'online' entities"
    )


def test_build_catalog_has_non_sensor_component(expose_db):
    """The catalog must contain at least one entity with component != 'sensor'."""
    from app.integrations.expose import build_catalog

    test_uuid = "aaaaaaaa-0000-0000-0000-000000000008"
    with Session(expose_db) as session:
        _make_modbus_device(session, friendly_name="SDM120 G", uuid=test_uuid)
        session.commit()

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    non_sensor = [e for e in catalog if e.entity.component != "sensor"]
    assert len(non_sensor) >= 1, (
        "Expected at least one non-sensor component (binary_sensor 'online')"
    )


def test_build_catalog_only_includes_enabled_devices(expose_db):
    """Disabled devices must not contribute entities to the catalog."""
    from app.models.modbus import ModbusDevice

    now = datetime.now(tz=timezone.utc)
    enabled_uuid = "aaaaaaaa-0000-0000-0000-000000000009"
    disabled_uuid = "aaaaaaaa-0000-0000-0000-00000000000a"

    with Session(expose_db) as session:
        enabled_device = ModbusDevice(
            uuid=enabled_uuid,
            friendly_name="Enabled Device",
            host="10.0.0.1",
            port=502,
            unit_id=1,
            profile="sdm120",
            poll_interval_s=5,
            enabled=True,
            created_at=now,
            updated_at=now,
        )
        disabled_device = ModbusDevice(
            uuid=disabled_uuid,
            friendly_name="Disabled Device",
            host="10.0.0.2",
            port=502,
            unit_id=2,
            profile="sdm120",
            poll_interval_s=5,
            enabled=False,
            created_at=now,
            updated_at=now,
        )
        session.add_all([enabled_device, disabled_device])
        session.commit()

    from app.integrations.expose import build_catalog

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    all_keys = {e.entity.key for e in catalog}
    assert any(enabled_uuid in k for k in all_keys), "Enabled device must be in catalog"
    assert not any(disabled_uuid in k for k in all_keys), (
        "Disabled device must NOT be in catalog"
    )


def test_build_catalog_key_uses_uuid_not_db_id(expose_db):
    """Entity keys must contain the device uuid, not the integer DB primary key."""
    from app.integrations.expose import build_catalog

    test_uuid = "bbbbbbbb-1111-0000-0000-000000000001"
    with Session(expose_db) as session:
        device = _make_modbus_device(session, friendly_name="UUID Key Test", uuid=test_uuid)
        session.commit()
        db_id = device.id  # type: ignore[union-attr]

    with Session(expose_db) as session:
        catalog = build_catalog(session)

    entity_keys = [e.entity.key for e in catalog if test_uuid in e.entity.key]
    assert len(entity_keys) > 0, "Expected entities for the test device"

    # Keys must contain the uuid string and not be keyed by integer id only.
    for key in entity_keys:
        assert test_uuid in key, f"Key {key!r} must contain the uuid {test_uuid!r}"
        # Ensure the integer DB id does not appear where the uuid should be.
        parts = key.split(".")
        assert str(db_id) not in parts[1:2], (
            f"Key {key!r} must not use the integer DB id {db_id} in the uuid slot"
        )


# ---------------------------------------------------------------------------
# 4. Migration shape tests
# ---------------------------------------------------------------------------


def test_exposed_entity_toggle_table_exists_after_upgrade(expose_db):
    """exposed_entity_toggle table must exist after upgrade to head."""
    inspector = inspect(expose_db)
    assert "exposed_entity_toggle" in inspector.get_table_names(), (
        "exposed_entity_toggle table missing after upgrade to head"
    )


def test_exposed_entity_toggle_columns(expose_db):
    """exposed_entity_toggle must have id, key, enabled, updated_at columns."""
    inspector = inspect(expose_db)
    columns = {col["name"]: col for col in inspector.get_columns("exposed_entity_toggle")}

    assert "id" in columns
    assert "key" in columns
    assert "enabled" in columns
    assert "updated_at" in columns

    # id must be non-nullable.
    assert not columns["id"]["nullable"]
    # key must be non-nullable.
    assert not columns["key"]["nullable"]
    # enabled must be non-nullable.
    assert not columns["enabled"]["nullable"]


def test_exposed_entity_toggle_key_unique_constraint(expose_db):
    """exposed_entity_toggle.key must have a unique constraint."""
    inspector = inspect(expose_db)
    unique_constraints = inspector.get_unique_constraints("exposed_entity_toggle")
    unique_cols = [col for uc in unique_constraints for col in uc["column_names"]]
    assert "key" in unique_cols, "key column must have a unique constraint"


def test_exposed_entity_toggle_key_unique_index(expose_db):
    """exposed_entity_toggle must have a unique index on key."""
    inspector = inspect(expose_db)
    indexes = {idx["name"]: idx for idx in inspector.get_indexes("exposed_entity_toggle")}
    assert "ix_exposed_entity_toggle_key" in indexes, (
        "Index ix_exposed_entity_toggle_key missing"
    )
    assert indexes["ix_exposed_entity_toggle_key"]["unique"]


def test_downgrade_removes_toggle_table(tmp_path: Path):
    """Downgrading to the revision before exposed_entity_toggle must drop that table cleanly.

    We downgrade to the explicit down_revision of the expose-toggle migration
    (``20260622_09_modbus_tables``) rather than using ``-1`` from head, so the test
    remains correct as new revisions are added on top.  This is the same pattern
    used in test_modbus_models.py for the modbus downgrade test.
    """
    db_path = tmp_path / "downgrade_expose_test.db"
    db_url = f"sqlite:///{db_path}"
    alembic_cfg = _make_app_alembic_config(db_url)

    command.upgrade(alembic_cfg, "head")

    engine = create_engine(db_url, connect_args={"check_same_thread": False})
    inspector = inspect(engine)
    assert "exposed_entity_toggle" in inspector.get_table_names()
    engine.dispose()

    # Downgrade to the explicit down_revision of the exposed_entity_toggle migration,
    # consistent with how test_modbus_models.py handles its own downgrade test.
    command.downgrade(alembic_cfg, "20260622_09_modbus_tables")

    engine = create_engine(db_url, connect_args={"check_same_thread": False})
    inspector = inspect(engine)
    table_names = inspector.get_table_names()
    assert "exposed_entity_toggle" not in table_names, (
        "exposed_entity_toggle should be gone after downgrade to 20260622_09_modbus_tables"
    )
    # Previous tables must still exist.
    assert "modbus_device" in table_names
    assert "modbus_reading" in table_names
    engine.dispose()


# ---------------------------------------------------------------------------
# 5. ORM round-trip tests
# ---------------------------------------------------------------------------


def test_expose_toggle_in_base_metadata():
    """Base.metadata.tables must include exposed_entity_toggle."""
    from app.db import Base

    # Importing the model registers it with Base.metadata.
    from app.models.expose import ExposedEntityToggle  # noqa: F401

    assert "exposed_entity_toggle" in Base.metadata.tables, (
        "exposed_entity_toggle not in Base.metadata after model import"
    )


def test_expose_toggle_insert_and_read(expose_db):
    """ExposedEntityToggle can be inserted and retrieved correctly."""
    from app.models.expose import ExposedEntityToggle

    now = datetime.now(tz=timezone.utc)
    key = "modbus.test-uuid.voltage"

    with Session(expose_db) as session:
        toggle = ExposedEntityToggle(key=key, enabled=True, updated_at=now)
        session.add(toggle)
        session.commit()
        toggle_id = toggle.id

    with Session(expose_db) as session:
        fetched = session.get(ExposedEntityToggle, toggle_id)
        assert fetched is not None
        assert fetched.key == key
        assert fetched.enabled is True


def test_expose_toggle_default_enabled_is_false(expose_db):
    """ExposedEntityToggle.enabled must default to False after INSERT (column default).

    SQLAlchemy applies ``default=False`` at INSERT time, not at Python object
    construction time.  We verify the column default by inserting a row without
    providing ``enabled`` and reading it back.
    """
    from app.models.expose import ExposedEntityToggle

    now = datetime.now(tz=timezone.utc)

    with Session(expose_db) as session:
        toggle = ExposedEntityToggle(key="default.enabled.test", updated_at=now)
        session.add(toggle)
        session.commit()
        toggle_id = toggle.id

    with Session(expose_db) as session:
        fetched = session.get(ExposedEntityToggle, toggle_id)
        assert fetched is not None
        assert fetched.enabled is False, (
            "ExposedEntityToggle.enabled must default to False (not True, not None)"
        )


def test_expose_toggle_key_uniqueness_enforced(expose_db):
    """Inserting two rows with the same key must raise an IntegrityError."""
    import sqlalchemy.exc

    from app.models.expose import ExposedEntityToggle

    now = datetime.now(tz=timezone.utc)
    key = "modbus.dup-uuid.power"

    with Session(expose_db) as session:
        session.add(ExposedEntityToggle(key=key, enabled=False, updated_at=now))
        session.commit()

    with pytest.raises(sqlalchemy.exc.IntegrityError):
        with Session(expose_db) as session:
            session.add(ExposedEntityToggle(key=key, enabled=True, updated_at=now))
            session.commit()


def test_expose_toggle_update(expose_db):
    """Updating an existing toggle row must persist the new enabled value."""
    from app.models.expose import ExposedEntityToggle

    now = datetime.now(tz=timezone.utc)
    key = "modbus.update-uuid.current"

    with Session(expose_db) as session:
        toggle = ExposedEntityToggle(key=key, enabled=False, updated_at=now)
        session.add(toggle)
        session.commit()
        toggle_id = toggle.id

    with Session(expose_db) as session:
        toggle = session.get(ExposedEntityToggle, toggle_id)
        toggle.enabled = True
        toggle.updated_at = datetime.now(tz=timezone.utc)
        session.commit()

    with Session(expose_db) as session:
        fetched = session.get(ExposedEntityToggle, toggle_id)
        assert fetched.enabled is True


# ---------------------------------------------------------------------------
# 6. APP_BASELINE_REVISION
# ---------------------------------------------------------------------------


def test_app_baseline_revision_matches_new_head(tmp_path: Path):
    """APP_BASELINE_REVISION must equal the Alembic head revision."""
    from alembic.script import ScriptDirectory

    from scripts.app_db_adopt import APP_BASELINE_REVISION

    db_url = f"sqlite:///{tmp_path / 'rev_check.db'}"
    alembic_cfg = _make_app_alembic_config(db_url)
    script = ScriptDirectory.from_config(alembic_cfg)
    heads = script.get_heads()
    assert len(heads) == 1, f"Expected exactly 1 Alembic head, got {heads}"
    head = heads[0]
    assert APP_BASELINE_REVISION == head, (
        f"APP_BASELINE_REVISION={APP_BASELINE_REVISION!r} does not match "
        f"Alembic head={head!r}"
    )