"""EntitlementService enforcement (ENTITLEMENTS.md §4, §5)."""

import pytest

from infrasynth.billing.entitlements import EntitlementService
from infrasynth.billing.models import App, Entitlement, Plan
from infrasynth.billing.services import BillingService
from infrasynth.tenancy.models import Tenant

pytestmark = pytest.mark.django_db


@pytest.fixture
def app():
    return App.objects.create(slug="messenger", name="Messenger", monetization="subscription")


@pytest.fixture
def plan(app):
    return Plan.objects.create(
        app=app,
        slug="pro",
        name="Pro",
        price_amount=1000,
        features={"broadcast": True, "analytics": False},
        limits={"max_agents": 10},
    )


def _entitlement(tenant, app, plan=None, status="active"):
    return Entitlement.all_objects.create(tenant=tenant, app=app, plan=plan, status=status)


class TestIsEntitled:
    def test_false_without_entitlement(self, tenant, app):
        assert EntitlementService().is_entitled(tenant, "messenger") is False

    def test_active_is_entitled(self, tenant, app, plan):
        _entitlement(tenant, app, plan)
        assert EntitlementService().is_entitled(tenant, "messenger") is True

    @pytest.mark.parametrize("status", ["trialing", "grace", "past_due"])
    def test_grace_and_trial_are_entitled(self, tenant, app, plan, status):
        _entitlement(tenant, app, plan, status=status)
        assert EntitlementService().is_entitled(tenant, "messenger") is True

    @pytest.mark.parametrize("status", ["suspended", "expired", "cancelled", "revoked"])
    def test_inactive_statuses_are_not_entitled(self, tenant, app, plan, status):
        _entitlement(tenant, app, plan, status=status)
        assert EntitlementService().is_entitled(tenant, "messenger") is False

    def test_suspended_tenant_denied_regardless_of_entitlement(self, tenant, app, plan):
        _entitlement(tenant, app, plan, status="active")
        tenant.status = Tenant.Status.SUSPENDED
        tenant.save(update_fields=["status"])
        assert EntitlementService().is_entitled(tenant, "messenger") is False

    def test_feature_gate_reads_plan_features(self, tenant, app, plan):
        _entitlement(tenant, app, plan)
        svc = EntitlementService()
        assert svc.is_entitled(tenant, "messenger", feature="broadcast") is True
        assert svc.is_entitled(tenant, "messenger", feature="analytics") is False
        assert svc.is_entitled(tenant, "messenger", feature="unknown") is False

    def test_none_tenant_is_never_entitled(self, app):
        assert EntitlementService().is_entitled(None, "messenger") is False


class TestCheckLimit:
    def test_within_and_at_limit(self, tenant, app, plan):
        _entitlement(tenant, app, plan)
        svc = EntitlementService()
        assert svc.check_limit(tenant, "messenger", "max_agents", 9) is True
        assert svc.check_limit(tenant, "messenger", "max_agents", 10) is False

    def test_missing_limit_is_unlimited(self, tenant, app, plan):
        _entitlement(tenant, app, plan)
        assert EntitlementService().check_limit(tenant, "messenger", "nonexistent", 10**9) is True

    def test_no_entitlement_denies(self, tenant, app):
        assert EntitlementService().check_limit(tenant, "messenger", "max_agents", 0) is False


class TestCacheInvalidation:
    def test_mutation_invalidates_cache(self, tenant, app, plan):
        entitlement = _entitlement(tenant, app, plan)
        svc = EntitlementService()
        assert svc.is_entitled(tenant, "messenger") is True
        entitlement.status = "revoked"
        entitlement.save(update_fields=["status"])
        # still cached
        assert svc.is_entitled(tenant, "messenger") is True
        svc.invalidate(tenant, "messenger")
        assert svc.is_entitled(tenant, "messenger") is False


class TestLifecycleTransitions:
    def test_past_due_grace_suspend_reinstate(self, tenant, app, plan):
        entitlement = _entitlement(tenant, app, plan)
        svc = BillingService()
        svc.mark_past_due(entitlement)
        assert EntitlementService().get(tenant, "messenger").status == "past_due"
        svc.enter_grace(entitlement)
        assert EntitlementService().is_entitled(tenant, "messenger") is True
        svc.suspend_entitlement(entitlement)
        assert EntitlementService().is_entitled(tenant, "messenger") is False
        svc.reinstate_entitlement(entitlement)
        assert EntitlementService().is_entitled(tenant, "messenger") is True