"""Contract tests for M8 source/channel/binding management routes."""

from __future__ import annotations

from datetime import UTC, datetime, timedelta
from decimal import Decimal
from queue import Empty, Queue
from types import SimpleNamespace
import threading
import time
from unittest.mock import patch

from fastapi.testclient import TestClient
from sqlalchemy import create_engine, select
from sqlalchemy.orm import Session

from app.models.config import AppConfigEntry
from app.models.energy import DsmrReading, Meter
from app.models.meter_source import MeterSource, MeterSourceBinding, MeterSourceChannel, WarmteLinkReading

_CSRF = "test-csrf-token"


def _login(client: TestClient) -> None:
    assert client.post("/api/auth/login", json={"username": "admin", "password": "test-password"}).status_code == 200


def _client(auth_database):
    from app.main import create_app

    engine = create_engine(auth_database["app_url"], connect_args={"check_same_thread": False})
    return TestClient(create_app()), engine


def _create_source(client: TestClient, *, config: dict | None = None) -> dict:
    response = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
        "name": "Synthetic DSMR", "kind": "dsmr_mqtt", "config": config or {},
    })
    assert response.status_code == 201
    return response.json()


def _add_channel(engine, source_uuid: str, *, key: str = "electricity") -> str:
    with Session(engine) as session:
        source = session.execute(select(MeterSource).where(MeterSource.uuid == source_uuid)).scalar_one()
        now = datetime.now(UTC)
        channel = MeterSourceChannel(
            source_id=source.id, channel_key=key, label="Electricity", unit="kWh",
            created_at=now, updated_at=now,
        )
        session.add(channel)
        session.commit()
        return channel.uuid


def test_source_profiles_and_crud_mask_secrets(auth_database):
    client, engine = _client(auth_database)
    with client:
        assert client.get("/api/energy/source-profiles").status_code == 401
        _login(client)
        profiles = client.get("/api/energy/source-profiles")
        assert profiles.status_code == 200
        assert {item["kind"] for item in profiles.json()["items"]} == {"dsmr_mqtt", "warmtelink_serial"}

        create = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Synthetic DSMR", "kind": "dsmr_mqtt",
            "config": {"username": "user", "password": "not-for-api"},
        })
        assert create.status_code == 201
        source = create.json()
        assert source["config"]["username"] == ""
        assert source["config"]["password"] == ""
        assert "not-for-api" not in str(source)

        patch = client.patch(f"/api/energy/sources/{source['uuid']}", headers={"X-CSRF-Token": _CSRF}, json={"config": {"password": ""}})
        assert patch.status_code == 200
        assert patch.json()["config"]["password"] == ""
        with Session(engine) as session:
            stored = session.execute(
                select(MeterSource).where(MeterSource.uuid == source["uuid"])
            ).scalar_one()
            assert stored.config["password"] == "not-for-api"
        assert client.post(f"/api/energy/sources/{source['uuid']}/discover", headers={"X-CSRF-Token": _CSRF}).status_code == 200
        assert client.delete(f"/api/energy/sources/{source['uuid']}", headers={"X-CSRF-Token": _CSRF}).status_code == 204
    engine.dispose()


def test_serial_source_reconciles_only_after_commit(auth_database, monkeypatch):
    """Creation and mutation trigger the worker manager after a successful commit."""
    from app.api.routes.api import meter_sources

    calls = []
    monkeypatch.setattr(meter_sources.warmtelink_worker_manager, "reconcile", lambda: calls.append(True))
    client, engine = _client(auth_database)
    with client:
        _login(client)
        baseline = len(calls)
        response = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Serial", "kind": "warmtelink_serial", "config": {"path": "/dev/ttyUSB0"},
        })
        assert response.status_code == 201
        source_uuid = response.json()["uuid"]
        assert len(calls) == baseline + 1
        assert client.patch(f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}, json={"enabled": False}).status_code == 200
        assert len(calls) == baseline + 2
    engine.dispose()


def test_serial_source_commit_is_not_reported_as_failed_when_reconcile_raises(auth_database, monkeypatch):
    from app.api.routes.api import meter_sources

    client, engine = _client(auth_database)
    with client:
        _login(client)
        monkeypatch.setattr(
            meter_sources.warmtelink_worker_manager, "reconcile",
            lambda: (_ for _ in ()).throw(RuntimeError()),
        )
        response = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Serial", "kind": "warmtelink_serial", "config": {"path": "/dev/ttyUSB0"},
        })
        assert response.status_code == 201
    engine.dispose()


def test_dsmr_crud_reconciles_runtime_and_invalidates_retained_callbacks(auth_database, monkeypatch):
    """CRUD converges real DSMR ownership, not merely a mocked reconcile call."""
    from app.api.routes.api import meter_sources
    from app.services import dsmr_ingest

    class FakeMqttManager:
        def __init__(self) -> None:
            self.handlers: dict[int, dict[str, object]] = {}
            self.replace_calls: list[tuple[int, dict[str, object]]] = []
            self.remove_calls: list[int] = []

        def replace_source(self, source_id: int, **kwargs: object) -> bool:
            self.replace_calls.append((source_id, kwargs))
            self.handlers[source_id] = kwargs["subscriptions"]  # type: ignore[assignment]
            kwargs["state_handler"]("connecting")  # type: ignore[operator]
            return True

        def remove_source(self, source_id: int) -> None:
            self.remove_calls.append(source_id)
            self.handlers.pop(source_id, None)

        def source_is_active(self, source_id: int) -> bool:
            return source_id in self.handlers

    mqtt = FakeMqttManager()
    warmtelink_calls: list[None] = []
    monkeypatch.setattr("app.integrations.mqtt.mqtt_manager", mqtt)
    monkeypatch.setattr(
        meter_sources.warmtelink_worker_manager, "reconcile", lambda: warmtelink_calls.append(None),
    )
    monkeypatch.setattr(dsmr_ingest, "_subscriptions", {})
    monkeypatch.setattr(dsmr_ingest, "_subscription_client_ids", {})
    monkeypatch.setattr(dsmr_ingest, "_subscription_tokens", {})
    monkeypatch.setattr(dsmr_ingest, "_tariffs", {})

    client, engine = _client(auth_database)
    with Session(engine) as session:
        session.add(AppConfigEntry(
            key="MQTT_CLIENT_ID", value="home-automation-api-test", updated_at=datetime.now(UTC),
        ))
        session.commit()
    payload = b'{"timestamp":"2030-01-01T00:00:00Z"}'
    with client:
        _login(client)
        baseline_warmtelink_calls = len(warmtelink_calls)
        created = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Managed DSMR", "kind": "dsmr_mqtt",
            "config": {"broker_host": "broker.test", "topic": "meter/first"},
        })
        assert created.status_code == 201
        assert created.json()["status"] == "connecting"
        source_uuid = created.json()["uuid"]
        with Session(engine) as session:
            source_id = session.scalar(select(MeterSource.id).where(MeterSource.uuid == source_uuid))
        assert source_id is not None
        first_handler = mqtt.handlers[source_id]["meter/first"]
        assert mqtt.replace_calls[-1][1]["base_client_id"] == "home-automation-api-test"

        updated = client.patch(
            f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF},
            json={"config": {"topic": "meter/second"}},
        )
        assert updated.status_code == 200
        assert updated.json()["status"] == "connecting"
        assert mqtt.remove_calls == [source_id]
        assert "meter/second" in mqtt.handlers[source_id]
        first_handler(payload)  # type: ignore[operator]
        with Session(engine) as session:
            assert session.query(DsmrReading).filter_by(meter_source_id=source_id).count() == 0

        retained_handler = mqtt.handlers[source_id]["meter/second"]
        disabled = client.patch(
            f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}, json={"enabled": False},
        )
        assert disabled.status_code == 200
        assert disabled.json()["status"] == "unknown"
        assert source_id not in mqtt.handlers
        retained_handler(payload)  # type: ignore[operator]
        with Session(engine) as session:
            assert session.query(DsmrReading).filter_by(meter_source_id=source_id).count() == 0

        assert client.patch(
            f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}, json={"enabled": True},
        ).status_code == 200
        delete_handler = mqtt.handlers[source_id]["meter/second"]
        assert client.delete(f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}).status_code == 204
        assert source_id not in mqtt.handlers
        delete_handler(payload)  # type: ignore[operator]
        with Session(engine) as session:
            assert session.get(MeterSource, source_id) is None
            assert session.query(DsmrReading).filter_by(meter_source_id=source_id).count() == 0
        assert len(warmtelink_calls) == baseline_warmtelink_calls + 5
    engine.dispose()


def test_source_crud_runtime_failures_do_not_hide_commits(auth_database, monkeypatch):
    from app.api.routes.api import meter_sources

    calls: list[str] = []
    client, engine = _client(auth_database)
    with client:
        _login(client)
        monkeypatch.setattr(
            meter_sources.warmtelink_worker_manager, "reconcile",
            lambda: calls.append("warmtelink") or (_ for _ in ()).throw(RuntimeError()),
        )
        monkeypatch.setattr(
            meter_sources, "apply_dsmr_subscription",
            lambda _settings: calls.append("dsmr") or (_ for _ in ()).throw(RuntimeError()),
        )
        created = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Durable DSMR", "kind": "dsmr_mqtt", "config": {},
        })
        assert created.status_code == 201
        source_uuid = created.json()["uuid"]
        assert calls == ["warmtelink", "dsmr"]
        assert client.patch(
            f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}, json={"enabled": False},
        ).status_code == 200
        assert client.delete(f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}).status_code == 204
        with Session(engine) as session:
            assert session.scalar(select(MeterSource.id).where(MeterSource.uuid == source_uuid)) is None
    engine.dispose()


def test_binding_routes_and_atomic_meter_declaration(auth_database):
    client, engine = _client(auth_database)
    with client:
        _login(client)
        source_response = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Synthetic DSMR", "kind": "dsmr_mqtt", "config": {},
        })
        source_uuid = source_response.json()["uuid"]
        with Session(engine) as session:
            source = session.query(MeterSource).filter_by(uuid=source_uuid).one()
            now = datetime.now(UTC)
            channel = MeterSourceChannel(
                source_id=source.id, channel_key="electricity", label="Electricity", unit="kWh",
                created_at=now, updated_at=now,
            )
            session.add(channel)
            session.commit()
            channel_uuid = channel.uuid

        declaration = {
            "label": "Bound meter", "started_at": "2030-01-01T00:00:00Z", "reason": "initial",
            "commodity": "electricity", "source_channel_uuid": channel_uuid,
        }
        created = client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json=declaration)
        assert created.status_code == 201
        assert created.json()["bindings"][0]["source_channel_uuid"] == channel_uuid
        meter_id = created.json()["id"]
        assert client.get(f"/api/energy/meters/{meter_id}/bindings").json()["total"] == 1
        assert client.get(f"/api/energy/sources/{source_uuid}/channels").json()["items"][0]["binding_count"] == 1

        invalid = dict(declaration, label="Must roll back", started_at="2030-02-01T00:00:00Z", source_channel_uuid="missing-channel")
        assert client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json=invalid).status_code == 404
        assert client.get("/api/energy/meters").json()["total"] == 1
        with Session(engine) as session:
            original = session.get(Meter, meter_id)
            assert original is not None
            assert original.ended_at is None
            assert session.execute(select(Meter).where(Meter.label == "Must roll back")).scalar_one_or_none() is None
            assert session.execute(select(MeterSourceBinding).where(MeterSourceBinding.meter_id == meter_id)).scalars().all()
    engine.dispose()


def test_source_and_binding_error_contracts_csrf_timezone_and_dsmr_compatibility(auth_database, monkeypatch):
    """Exercise the public error boundary without opening serial or MQTT I/O."""
    from zoneinfo import ZoneInfo

    from app.services import timezone as timezone_service

    monkeypatch.setattr(timezone_service, "local_tz", lambda: ZoneInfo("Europe/Amsterdam"))
    client, engine = _client(auth_database)
    with client:
        # All management reads require a session and mutations require CSRF.
        assert client.get("/api/energy/commodities").status_code == 401
        _login(client)
        assert client.post("/api/energy/sources", json={
            "name": "No CSRF", "kind": "dsmr_mqtt", "config": {},
        }).status_code == 403
        assert client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Invalid", "kind": "dsmr_mqtt", "config": {"unexpected": True},
        }).status_code == 422
        assert client.get("/api/energy/sources/does-not-exist").status_code == 404

        source = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "DSMR source", "kind": "dsmr_mqtt", "config": {"password": "stored-secret"},
        })
        assert source.status_code == 201
        source_uuid = source.json()["uuid"]
        assert "stored-secret" not in client.get(f"/api/energy/sources/{source_uuid}").text
        assert client.get("/api/energy/commodities").json()["items"] == [
            {"key": "electricity", "unit": "kWh", "capabilities": ["meter", "binding", "cost"]},
            {"key": "heating", "unit": "GJ", "capabilities": ["meter", "binding"]},
            {"key": "hot_water", "unit": "m³", "capabilities": ["meter", "binding"]},
        ]

        with Session(engine) as session:
            source_model = session.query(MeterSource).filter_by(uuid=source_uuid).one()
            now = datetime.now(UTC)
            channel = MeterSourceChannel(
                source_id=source_model.id, channel_key="electricity", label="Electricity", unit="kWh",
                created_at=now, updated_at=now,
            )
            session.add(channel)
            session.add(DsmrReading(
                meter_source_id=source_model.id, telegram_id=7, recorded_at=now,
                payload={"compatibility": "latest"},
            ))
            session.commit()
            channel_uuid = channel.uuid

        # Retained channels prohibit deletion; there is no cascade escape hatch.
        assert client.delete(f"/api/energy/sources/{source_uuid}", headers={"X-CSRF-Token": _CSRF}).status_code == 409
        assert client.get(f"/api/energy/sources/{source_uuid}/channels/not-a-channel/readings").status_code == 404
        readings = client.get(f"/api/energy/sources/{source_uuid}/channels/{channel_uuid}/readings")
        assert readings.status_code == 200
        assert readings.json()["total"] == 1
        assert readings.json()["items"] == [{"recorded_at": now.isoformat().replace("+00:00", ""), "value": None, "quality": None}]
        assert "telegram_id" not in readings.text
        latest = client.get("/api/energy/dsmr/latest")
        assert latest.status_code == 200
        assert latest.json()["payload"] == {"compatibility": "latest"}

        # This declaration is deliberately retroactive for timezone coverage;
        # mock the billing sweep so the API contract test stays bounded.
        with patch("app.api.routes.api.meters.recompute_range", return_value=0):
            meter = client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json={
                "label": "Local-time meter", "started_at": "2025-01-02T00:00:00", "reason": "initial",
            })
        assert meter.status_code == 201
        meter_id = meter.json()["id"]
        binding = client.post(f"/api/energy/meters/{meter_id}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2025-01-02T00:00:00",
        })
        assert binding.status_code == 201
        binding_body = binding.json()
        localized_start = datetime.fromisoformat(binding_body["started_at"].replace("Z", "+00:00"))
        # SQLite returns UTC columns without tzinfo; retain the UTC clock instant
        # regardless of that transport detail.
        assert localized_start.replace(tzinfo=None) == datetime(2025, 1, 1, 23, 0, 0)
        assert client.post(f"/api/energy/meters/{meter_id}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2025-01-02T00:00:00",
        }).status_code == 422
        assert client.patch(f"/api/energy/bindings/{binding_body['uuid']}", headers={"X-CSRF-Token": _CSRF}, json={
            "ended_at": "2025-01-02T00:00:00",
        }).status_code == 422
        assert client.patch(f"/api/energy/bindings/{binding_body['uuid']}", headers={"X-CSRF-Token": _CSRF}, json={
            "ended_at": "2025-01-03T00:00:00",
        }).status_code == 200
        assert client.patch("/api/energy/bindings/not-a-binding", headers={"X-CSRF-Token": _CSRF}, json={
            "ended_at": "2025-01-03T00:00:00",
        }).status_code == 404
    engine.dispose()


def test_management_reads_require_auth_and_mutations_require_csrf(auth_database):
    """Every M8-T06 management route enforces the session/CSRF contract."""
    client, engine = _client(auth_database)
    with client:
        for path in (
            "/api/energy/source-profiles",
            "/api/energy/commodities",
            "/api/energy/sources",
            "/api/energy/sources/missing",
            "/api/energy/sources/missing/channels",
            "/api/energy/sources/missing/channels/missing/readings",
            "/api/energy/meters/1/bindings",
        ):
            assert client.get(path).status_code == 401

        _login(client)
        assert client.post("/api/energy/sources", json={
            "name": "No CSRF", "kind": "dsmr_mqtt", "config": {},
        }).status_code == 403
        source = _create_source(client)
        channel_uuid = _add_channel(engine, source["uuid"])
        meter = client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json={
            "label": "CSRF meter", "started_at": "2030-01-01T00:00:00Z", "reason": "initial",
        })
        assert meter.status_code == 201
        meter_id = meter.json()["id"]
        binding = client.post(f"/api/energy/meters/{meter_id}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2030-01-01T00:00:00Z",
        })
        assert binding.status_code == 201

        assert client.patch(f"/api/energy/sources/{source['uuid']}", json={"name": "blocked"}).status_code == 403
        assert client.delete(f"/api/energy/sources/{source['uuid']}").status_code == 403
        assert client.post(f"/api/energy/sources/{source['uuid']}/discover").status_code == 403
        assert client.post(f"/api/energy/meters/{meter_id}/bindings", json={
            "source_channel_uuid": channel_uuid, "started_at": "2031-01-01T00:00:00Z",
        }).status_code == 403
        assert client.patch(f"/api/energy/bindings/{binding.json()['uuid']}", json={}).status_code == 403
    engine.dispose()


def test_source_channel_binding_response_contract_and_discover_capabilities(auth_database):
    client, engine = _client(auth_database)
    with client:
        _login(client)
        source = _create_source(client, config={"username": "private-user", "password": "private-secret"})
        channel_uuid = _add_channel(engine, source["uuid"])
        with Session(engine) as session:
            source_model = session.query(MeterSource).filter_by(uuid=source["uuid"]).one()
            source_model.status = "online"
            source_model.last_seen_at = datetime.now(UTC)
            source_model.last_error = None
            session.commit()
        listed = client.get("/api/energy/sources")
        assert listed.status_code == 200
        assert listed.json()["total"] >= 1
        source_item = next(item for item in listed.json()["items"] if item["uuid"] == source["uuid"])
        assert source_item["uuid"] == source["uuid"]
        detail = client.get(f"/api/energy/sources/{source['uuid']}")
        assert detail.status_code == 200
        assert detail.json()["uuid"] == source["uuid"]
        for body in (listed.json(), detail.json()):
            rendered = str(body)
            assert "private-secret" not in rendered
            assert "channel_key" not in rendered
            assert "fingerprint" not in rendered

        discovered = client.post(f"/api/energy/sources/{source['uuid']}/discover", headers={"X-CSRF-Token": _CSRF})
        assert discovered.status_code == 200
        assert discovered.json() == {
            "requested": False, "supported": True, "status": "managed_by_runtime",
            "request_id": None,
            "detail": "This source is discovered by its runtime subscription; no connection was opened.",
            "channels": [],
        }
        channels = client.get(f"/api/energy/sources/{source['uuid']}/channels")
        assert channels.status_code == 200
        channel = channels.json()["items"][0]
        assert channel["uuid"] == channel_uuid
        assert set(channel) == {
            "uuid", "label", "suggested_commodity", "unit", "device_type", "latest_value",
            "latest_at", "latest_quality", "binding_count", "bound_meter_ids", "binding_summary",
        }
        assert channels.json()["source_status"] == "online"

        meter = client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json={
            "label": "Contract meter", "started_at": "2030-01-01T00:00:00Z", "reason": "initial",
        })
        assert meter.status_code == 201
        binding = client.post(f"/api/energy/meters/{meter.json()['id']}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2030-01-01T00:00:00Z",
        })
        assert binding.status_code == 201
        binding_item = client.get(f"/api/energy/meters/{meter.json()['id']}/bindings").json()["items"][0]
        assert binding_item["uuid"] == binding.json()["uuid"]
        assert binding_item["source_uuid"] == source["uuid"]
        assert binding_item["source_channel_uuid"] == channel_uuid
        assert set(binding_item) == {
            "uuid", "meter_id", "source_channel_uuid", "source_uuid", "started_at", "ended_at",
            "created_at", "updated_at",
        }
    engine.dispose()


def test_binding_patch_omitted_null_and_adjacent_half_open_boundaries(auth_database):
    client, engine = _client(auth_database)
    with client:
        _login(client)
        source = _create_source(client)
        channel_uuid = _add_channel(engine, source["uuid"])
        meter = client.post("/api/energy/meters", headers={"X-CSRF-Token": _CSRF}, json={
            "label": "Timeline meter", "started_at": "2030-01-01T00:00:00Z", "reason": "initial",
        })
        assert meter.status_code == 201
        meter_id = meter.json()["id"]
        first = client.post(f"/api/energy/meters/{meter_id}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2030-01-01T00:00:00Z",
            "ended_at": "2030-02-01T00:00:00Z",
        })
        assert first.status_code == 201
        first_uuid = first.json()["uuid"]
        corrected = client.patch(f"/api/energy/bindings/{first_uuid}", headers={"X-CSRF-Token": _CSRF}, json={
            "started_at": "2030-01-02T00:00:00Z",
        })
        assert corrected.status_code == 200
        assert corrected.json()["ended_at"] == "2030-02-01T00:00:00"
        unchanged = client.patch(f"/api/energy/bindings/{first_uuid}", headers={"X-CSRF-Token": _CSRF}, json={})
        assert unchanged.status_code == 200
        assert unchanged.json()["ended_at"] == "2030-02-01T00:00:00"
        reopened = client.patch(f"/api/energy/bindings/{first_uuid}", headers={"X-CSRF-Token": _CSRF}, json={"ended_at": None})
        assert reopened.status_code == 200
        assert reopened.json()["ended_at"] is None
        reclosed = client.patch(f"/api/energy/bindings/{first_uuid}", headers={"X-CSRF-Token": _CSRF}, json={
            "ended_at": "2030-02-01T00:00:00Z",
        })
        assert reclosed.status_code == 200
        adjacent = client.post(f"/api/energy/meters/{meter_id}/bindings", headers={"X-CSRF-Token": _CSRF}, json={
            "source_channel_uuid": channel_uuid, "started_at": "2030-02-01T00:00:00Z",
        })
        assert adjacent.status_code == 201
    engine.dispose()


def test_warmtelink_discover_and_minute_history_are_bounded_and_private(auth_database, monkeypatch):
    """Discover delegates to the manager; readings expose accepted minute samples only."""
    from app.api.routes.api import meter_sources

    requested: list[int] = []
    monkeypatch.setattr(
        meter_sources.warmtelink_worker_manager, "request_discovery",
        lambda source_id: requested.append(source_id) or SimpleNamespace(
            status="completed", request_id=1, detail=None, completed=SimpleNamespace(is_set=lambda: False),
        ),
    )
    monkeypatch.setattr(meter_sources.warmtelink_worker_manager, "reconcile", lambda: None)
    client, engine = _client(auth_database)
    with client:
        _login(client)
        created = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "WarmteLink", "kind": "warmtelink_serial", "config": {"path": "/dev/fake"},
        })
        assert created.status_code == 201
        source_uuid = created.json()["uuid"]
        now = datetime(2030, 1, 1, 12, 0, 30, tzinfo=UTC)
        with Session(engine) as session:
            source = session.execute(select(MeterSource).where(MeterSource.uuid == source_uuid)).scalar_one()
            source.status = "online"
            channel = MeterSourceChannel(
                source_id=source.id, channel_key="heating", label="Heating", unit="GJ",
                latest_value=Decimal("7.002"), latest_at=now, latest_quality="unverifiable",
                created_at=now, updated_at=now,
            )
            session.add(channel)
            session.flush()
            session.add_all([
                WarmteLinkReading(
                    channel_id=channel.id, recorded_at=now - timedelta(minutes=1), received_at=now,
                    value=Decimal("7.001"), unit="GJ", quality="unverifiable", equipment_fingerprint="masked",
                ),
                WarmteLinkReading(
                    channel_id=channel.id, recorded_at=now, received_at=now,
                    value=Decimal("7.002"), unit="GJ", quality="unverifiable", equipment_fingerprint="masked",
                ),
            ])
            session.commit()
            channel_uuid = channel.uuid

        discover = client.post(f"/api/energy/sources/{source_uuid}/discover", headers={"X-CSRF-Token": _CSRF})
        assert discover.status_code == 200
        assert discover.json()["status"] == "completed"
        assert requested and "fingerprint" not in discover.text and "channel_key" not in discover.text
        assert discover.json()["channels"][0]["latest_quality"] == "unverifiable"

        history = client.get(
            f"/api/energy/sources/{source_uuid}/channels/{channel_uuid}/readings",
            params={"from": "2030-01-01T11:59:00Z", "to": "2030-01-01T12:01:00Z", "limit": 1},
        )
        assert history.status_code == 200
        assert history.json()["total"] == 1
        assert history.json()["items"] == [{
            "recorded_at": "2030-01-01T11:59:30", "value": "7.001", "quality": "unverifiable",
        }]
        assert client.get(
            f"/api/energy/sources/{source_uuid}/channels/{channel_uuid}/readings",
            params={"from": "2030-01-01T12:01:00Z", "to": "2030-01-01T12:00:00Z"},
        ).status_code == 422
        assert client.get(
            f"/api/energy/sources/{source_uuid}/channels/{channel_uuid}/readings", params={"limit": 0}
        ).status_code == 422
    engine.dispose()


def test_warmtelink_discover_auth_csrf_disabled_and_source_ownership(auth_database, monkeypatch):
    from app.api.routes.api import meter_sources

    monkeypatch.setattr(
        meter_sources.warmtelink_worker_manager, "request_discovery",
        lambda _source_id: SimpleNamespace(
            status="pending", request_id=1, detail=None, completed=SimpleNamespace(is_set=lambda: False),
        ),
    )
    monkeypatch.setattr(meter_sources.warmtelink_worker_manager, "reconcile", lambda: None)
    client, engine = _client(auth_database)
    with client:
        serial = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Serial", "kind": "warmtelink_serial", "enabled": False, "config": {"path": "/dev/fake"},
        })
        assert serial.status_code == 401  # no session yet
        _login(client)
        serial = client.post("/api/energy/sources", headers={"X-CSRF-Token": _CSRF}, json={
            "name": "Serial", "kind": "warmtelink_serial", "enabled": False, "config": {"path": "/dev/fake"},
        })
        other = _create_source(client)
        channel_uuid = _add_channel(engine, other["uuid"])
        assert client.post(f"/api/energy/sources/{serial.json()['uuid']}/discover").status_code == 403
        disabled = client.post(
            f"/api/energy/sources/{serial.json()['uuid']}/discover", headers={"X-CSRF-Token": _CSRF}
        )
        assert disabled.status_code == 200 and disabled.json()["status"] == "error"
        assert client.get(
            f"/api/energy/sources/{serial.json()['uuid']}/channels/{channel_uuid}/readings"
        ).status_code == 404
    engine.dispose()


def test_discovery_manager_is_source_scoped_and_never_replaces_a_worker(auth_database):
    """The real manager queues requests on one fake read-only serial owner."""
    from app.services.warmtelink_worker import WarmteLinkWorkerManager

    engine = create_engine(auth_database["app_url"], connect_args={"check_same_thread": False})
    with Session(engine) as session:
        now = datetime.now(UTC)
        source = MeterSource(
            name="Serial", kind="warmtelink_serial", enabled=True, config={"path": "/dev/fake"},
            created_at=now, updated_at=now,
        )
        session.add(source)
        session.commit()
        source_id = source.id

    class FakeReadOnlyWorker:
        instances: list["FakeReadOnlyWorker"] = []

        def __init__(self, _source_id, _config, **_kwargs):
            self.requests = []
            self.thread = SimpleNamespace(is_alive=lambda: True)
            self.__class__.instances.append(self)

        def start(self):
            return None

        def stop(self):
            return None

        def join(self, timeout=5):
            return True

        def request_discovery(self, request):
            self.requests.append(request)

    manager = WarmteLinkWorkerManager(
        session_factory=lambda: Session(engine), worker_factory=FakeReadOnlyWorker,
    )
    manager.reconcile()
    assert manager.worker_count == 1
    first = manager.request_discovery(source_id)
    assert first.status == "pending"
    worker = FakeReadOnlyWorker.instances[0]
    assert len(worker.requests) == 1
    # A client timing out/cancelling leaves the queued request and worker alone;
    # completing it later cannot open another descriptor or create bindings.
    worker.requests[0].status = "completed"
    worker.requests[0].completed.set()
    results = []
    threads = [threading.Thread(target=lambda: results.append(manager.request_discovery(source_id))) for _ in range(2)]
    for thread in threads:
        thread.start()
    for thread in threads:
        thread.join()
    assert manager.worker_count == 1
    assert len(FakeReadOnlyWorker.instances) == 1
    assert len(worker.requests) == 3
    with Session(engine) as session:
        assert session.query(Meter).count() == 0
        assert session.query(MeterSourceBinding).count() == 0
    manager.shutdown()
    engine.dispose()


def test_real_warmtelink_discovery_waits_for_admission_and_keeps_its_serial_owner(
    auth_database, monkeypatch,
):
    """A rejected candidate is neither a discovery success nor exposed metadata."""
    from app.integrations.p1 import dsmr_crc16
    from app.services.warmtelink_ingest import WarmteLinkIngestor
    from app.services import warmtelink_worker
    from app.services.warmtelink_worker import WarmteLinkWorker, WarmteLinkWorkerManager

    engine = create_engine(auth_database["app_url"], connect_args={"check_same_thread": False})
    received_at = datetime(2026, 8, 22, 10, 0, 30, tzinfo=UTC)  # 12:00:30 Europe/Amsterdam.
    with Session(engine) as session:
        source = MeterSource(
            name="Serial", kind="warmtelink_serial", enabled=True, config={"path": "/dev/fake"},
            created_at=received_at, updated_at=received_at,
        )
        session.add(source)
        session.commit()
        source_id = source.id

    def frame(second: int, *, crc: bool = False) -> bytes:
        body = (
            b"/WARMTE\r\n"
            + f"0-0:1.0.0(2608221200{second:02d}S)\r\n".encode()
            + b"0-0:96.1.1(REDACTED)\r\n"
            + b"0-1:24.1.0(006)\r\n"
            + b"0-1:96.1.0(REDACTED)\r\n"
            + f"0-1:24.2.1(2608221200{second:02d}S)(5.900*m3)\r\n".encode()
            + b"0-2:24.1.0(012)\r\n"
            + b"0-2:96.1.0(REDACTED)\r\n"
            + f"0-2:24.2.1(2608221200{second:02d}S)(0.017*GJ)\r\n".encode()
        )
        payload = body + b"!"
        return payload + (f"{dsmr_crc16(payload):04X}".encode() if crc else b"") + b"\r\n"

    class FakeReadOnlySerial:
        instances: list["FakeReadOnlySerial"] = []

        def __init__(self):
            self.frames: Queue[bytes] = Queue()
            self.closed = False
            self.__class__.instances.append(self)

        def read(self, _size: int = 1) -> bytes:
            try:
                return self.frames.get(timeout=0.01)
            except Empty:
                return b""

        def close(self) -> None:
            self.closed = True

    monkeypatch.setattr(warmtelink_worker, "_DISCOVERY_TIMEOUT_SECONDS", 0.15)
    monkeypatch.setattr(warmtelink_worker, "_DISCOVERY_WAIT_SECONDS", 0.02)
    manager = WarmteLinkWorkerManager(
        session_factory=lambda: Session(engine), serial_factory=lambda _config: FakeReadOnlySerial(),
        worker_factory=lambda source_id, config, **kwargs: WarmteLinkWorker(
            source_id,
            config,
            ingestor=WarmteLinkIngestor(clock=lambda: received_at),
            **kwargs,
        ),
    )
    manager.reconcile()
    serial = FakeReadOnlySerial.instances[0]

    request = manager.request_discovery(source_id)
    assert request.status == "pending"
    serial.frames.put(frame(0))  # First unverifiable candidate is not admitted.
    time.sleep(0.04)
    assert not request.completed.is_set()
    with Session(engine) as session:
        assert session.query(MeterSourceChannel).filter_by(source_id=source_id).count() == 0
        assert session.query(MeterSourceBinding).count() == 0

    serial.frames.put(frame(10))  # Strictly continuous successor admits both channels.
    assert request.completed.wait(1)
    assert request.status == "completed"
    with Session(engine) as session:
        assert session.query(MeterSourceChannel).filter_by(source_id=source_id).count() == 2
        assert session.query(MeterSourceBinding).count() == 0

    rejected = manager.request_discovery(source_id)
    assert rejected.status == "pending"
    serial.frames.put(b"/malformed!\r\n")
    assert rejected.completed.wait(1)
    assert rejected.status == "error" and rejected.detail == "Discovery timed out."
    assert manager.worker_count == 1 and len(FakeReadOnlySerial.instances) == 1

    recovered = manager.request_discovery(source_id)
    serial.frames.put(frame(20, crc=True))
    assert recovered.completed.wait(1)
    assert recovered.status == "completed"
    assert manager.worker_count == 1 and len(FakeReadOnlySerial.instances) == 1
    manager.shutdown()
    assert serial.closed
    engine.dispose()