from __future__ import annotations

import tempfile
import unittest
from datetime import UTC, datetime
from pathlib import Path

from alembic import command
from alembic.runtime.migration import MigrationContext
from sqlalchemy import MetaData, Table, create_engine, inspect, select

from govoplan_connectors.backend.manifest import get_manifest
from govoplan_core.db.migrations import alembic_config, migrate_database


class ConnectorsMigrationTests(unittest.TestCase):
    def test_csv_evidence_upgrade_preserves_legacy_snapshot_without_inventing_source(self) -> None:
        with tempfile.TemporaryDirectory(prefix="govoplan-connectors-csv-migration-") as directory:
            url = f"sqlite:///{Path(directory) / 'connectors.db'}"
            config = alembic_config(database_url=url, enabled_modules=("connectors",), manifest_factories=(get_manifest,))
            command.upgrade(config, "c0f1a2b3c4d5")
            engine = create_engine(url)
            try:
                table = Table("connector_tabular_sources", MetaData(), autoload_with=engine)
                now = datetime.now(UTC)
                with engine.begin() as connection:
                    connection.execute(table.insert().values(
                        id="legacy-csv", tenant_id="tenant-1", provider="snapshot",
                        source_name="legacy", name="Legacy", status="active", schema_version=1,
                        schema=[{"name": "id", "data_type": "integer", "nullable": False}],
                        rows=[{"id": 1}], fingerprint="a" * 64, row_count=1, byte_count=10,
                        metadata={"original_label": "CSV"}, created_at=now, updated_at=now,
                    ))
                    before = dict(connection.execute(select(table)).mappings().one())
                command.upgrade(config, "d2a4c6e8f0b1")
                upgraded = Table("connector_tabular_sources", MetaData(), autoload_with=engine)
                with engine.connect() as connection:
                    after = dict(connection.execute(select(upgraded)).mappings().one())
                self.assertIsNone(after.pop("csv_source"))
                self.assertEqual(before, after)
            finally:
                engine.dispose()

    def test_baseline_creates_connector_tables_and_head(self) -> None:
        with tempfile.TemporaryDirectory(prefix="govoplan-connectors-migration-") as directory:
            url = f"sqlite:///{Path(directory) / 'connectors.db'}"
            migrate_database(
                database_url=url,
                enabled_modules=("connectors",),
                manifest_factories=(get_manifest,),
            )
            engine = create_engine(url)
            try:
                with engine.connect() as connection:
                    self.assertIn(
                        "d2a4c6e8f0b1",
                        set(MigrationContext.configure(connection).get_current_heads()),
                    )
                    self.assertTrue(
                        {
                            "connector_tabular_sources",
                            "connector_sanctions_snapshots",
                            "connector_sanctions_acquisition_runs",
                            "connector_definitions",
                            "connector_definition_revisions",
                            "connector_configurations",
                            "connector_simulation_runs",
                            "connector_knowledge_profiles",
                            "connector_knowledge_objects",
                            "connector_knowledge_sync_runs",
                            "connector_service_desk_profiles",
                            "connector_service_desk_objects",
                            "connector_service_desk_sync_runs",
                        }.issubset(inspect(connection).get_table_names())
                    )
            finally:
                engine.dispose()


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