from __future__ import annotations

import json
import unittest

from sqlalchemy import create_engine
from sqlalchemy.orm import Session, sessionmaker
from sqlalchemy.pool import StaticPool

from govoplan_core.core.concurrency import RevisionConflictError
from govoplan_core.core.dsar import (
    DsarErasureActionRef,
    DsarExecutionResultRef,
    DsarRecordRef,
    DsarSubjectRef,
)
from govoplan_core.db.base import Base
from govoplan_core.privacy.dsar_workflow import (
    DataSubjectRequest,
    create_data_subject_request,
    data_subject_export,
    execute_data_subject_erasure,
    plan_data_subject_erasure,
    search_data_subject_request,
)


class _Provider:
    provider_id = "example"
    module_id = "example"

    def __init__(self) -> None:
        self.executions = 0

    def search_subject(self, session, *, tenant_id, subject):
        del session, tenant_id, subject
        return (
            DsarRecordRef(
                provider_id=self.provider_id,
                module_id=self.module_id,
                resource_type="profile",
                resource_id="profile-1",
                category="personal",
                title="Example profile",
                data={"name": "Ada"},
            ),
            DsarRecordRef(
                provider_id=self.provider_id,
                module_id=self.module_id,
                resource_type="audit_evidence",
                resource_id="event-1",
                category="evidence",
                title="Decision event",
                immutable_evidence=True,
                retention_reason="Required decision evidence.",
            ),
        )

    def plan_erasure(self, session, *, tenant_id, subject, records):
        del session, tenant_id, subject, records
        return (
            DsarErasureActionRef(
                action_id="example:anonymize:profile-1",
                provider_id=self.provider_id,
                module_id=self.module_id,
                kind="anonymize",
                resource_type="profile",
                resource_id="profile-1",
                title="Anonymize profile",
                rationale="Remove profile data.",
                executable=True,
                irreversible=True,
            ),
        )

    def execute_erasure(self, session, *, tenant_id, subject, actions, request_id):
        del session, tenant_id, subject, request_id
        self.executions += 1
        return tuple(
            DsarExecutionResultRef(
                action_id=action.action_id,
                status="executed",
                summary="Profile anonymized.",
            )
            for action in actions
        )


class _Registry:
    def __init__(self, provider: _Provider) -> None:
        self.provider = provider

    def capability_names(self):
        return ("privacy.dsar.example", "privacy.dsar.inactive")

    def capability_owner(self, name):
        return {
            "privacy.dsar.example": "example",
            "privacy.dsar.inactive": "inactive",
        }[name]

    def tenant_entitlement_resolver(self):
        class _Resolver:
            @staticmethod
            def resolve(session, tenant_id):
                del session, tenant_id
                return type(
                    "State",
                    (),
                    {"effective_modules": ("example", "without-provider")},
                )()

        return _Resolver()

    def require_tenant_capability(self, name, session, **kwargs):
        del name, session, kwargs
        return self.provider

    def manifests(self):
        return (
            type("Manifest", (), {"id": "example"})(),
            type("Manifest", (), {"id": "without-provider"})(),
        )


class DsarWorkflowTests(unittest.TestCase):
    def setUp(self) -> None:
        self.engine = create_engine(
            "sqlite+pysqlite://",
            connect_args={"check_same_thread": False},
            poolclass=StaticPool,
        )
        DataSubjectRequest.__table__.create(self.engine)
        self.session: Session = sessionmaker(
            bind=self.engine,
            expire_on_commit=False,
        )()
        self.provider = _Provider()
        self.registry = _Registry(self.provider)

    def tearDown(self) -> None:
        self.session.close()
        Base.metadata.drop_all(self.engine, tables=[DataSubjectRequest.__table__])
        self.engine.dispose()

    def test_search_plan_export_and_idempotent_execution(self) -> None:
        row = create_data_subject_request(
            self.session,
            tenant_id="tenant-1",
            reference="DSAR-2026-001",
            request_kind="access_and_erasure",
            subject=DsarSubjectRef(email="ada@example.test"),
            purpose="Respond to a verified data-subject request.",
            legal_basis="Article 15 and 17 GDPR",
            due_at=None,
            requested_by_account_id="account-operator",
        )
        self.session.commit()

        search_data_subject_request(
            self.session,
            registry=self.registry,
            row=row,
            expected_revision=1,
        )
        self.assertEqual("searched", row.status)
        self.assertEqual(2, row.search_result["record_count"])
        self.assertEqual(["without-provider"], row.coverage["modules_without_provider"])
        self.assertEqual(
            ["privacy.dsar.inactive"],
            row.coverage["inactive_provider_capabilities"],
        )

        plan_data_subject_erasure(
            self.session,
            registry=self.registry,
            row=row,
            expected_revision=2,
        )
        actions = row.erasure_plan["actions"]
        self.assertEqual(2, len(actions))
        self.assertEqual(1, row.erasure_plan["retained_count"])
        executable_id = next(item["action_id"] for item in actions if item["executable"])

        execute_data_subject_erasure(
            self.session,
            registry=self.registry,
            row=row,
            expected_revision=3,
            action_ids=[executable_id],
        )
        self.assertEqual("completed", row.status)
        self.assertEqual(1, self.provider.executions)

        export = json.loads(data_subject_export(row))
        self.assertEqual("govoplan.dsars.export.v1", export["schema"])
        self.assertEqual("DSAR-2026-001", export["request"]["reference"])
        self.assertEqual(64, len(export["manifest_sha256"]))

        with self.assertRaises(RevisionConflictError):
            search_data_subject_request(
                self.session,
                registry=self.registry,
                row=row,
                expected_revision=1,
            )

    def test_access_only_request_cannot_create_erasure_plan(self) -> None:
        row = create_data_subject_request(
            self.session,
            tenant_id="tenant-1",
            reference="DSAR-2026-002",
            request_kind="access",
            subject=DsarSubjectRef(account_id="account-1"),
            purpose="Provide access information.",
            legal_basis=None,
            due_at=None,
            requested_by_account_id="account-operator",
        )
        search_data_subject_request(
            self.session,
            registry=self.registry,
            row=row,
            expected_revision=1,
        )
        with self.assertRaisesRegex(ValueError, "does not include erasure"):
            plan_data_subject_erasure(
                self.session,
                registry=self.registry,
                row=row,
                expected_revision=2,
            )


if __name__ == "__main__":
    unittest.main()