from __future__ import annotations

import csv
import tempfile
import unittest
from pathlib import Path

from shanghai_housing.db import connect, import_template_file
from shanghai_housing.import_templates import validate_csv_file, validate_import_rows
from shanghai_housing.raw_artifacts import fingerprint_file


class ImportTemplateTests(unittest.TestCase):
    def test_validates_area_monthly_metrics_template_file(self) -> None:
        result = validate_csv_file(
            "area_monthly_metrics",
            Path("docs/import_templates/area_monthly_metrics.csv"),
        )

        self.assertTrue(result.valid)
        self.assertEqual(result.row_count, 1)
        self.assertEqual(result.errors, [])

    def test_reports_missing_required_value_and_invalid_range(self) -> None:
        rows = [
            {
                "area_id": "",
                "month": "2026-13",
                "transaction_count": "-1",
                "transaction_price_psm": "abc",
                "listing_count": "10",
                "listing_price_psm": "100",
                "median_days_on_market": "30",
                "rent_price_psm": "3",
                "new_supply_units": "0",
                "land_residential_gfa_sqm": "0",
                "mortgage_rate_pct": "3.35",
                "policy_signal": "3",
                "source": "manual",
            }
        ]

        result = validate_import_rows("area_monthly_metrics", rows)

        self.assertFalse(result.valid)
        messages = {(error.column, error.message) for error in result.errors}
        self.assertIn(("area_id", "value is required"), messages)
        self.assertIn(("month", "must be YYYY-MM"), messages)
        self.assertIn(("transaction_count", "must be >= 0"), messages)
        self.assertIn(("transaction_price_psm", "must be a number"), messages)
        self.assertIn(("policy_signal", "must be <= 2"), messages)

    def test_reports_unexpected_headers_from_csv(self) -> None:
        with tempfile.TemporaryDirectory() as tmpdir:
            path = Path(tmpdir) / "bad.csv"
            with path.open("w", encoding="utf-8", newline="") as handle:
                writer = csv.DictWriter(handle, fieldnames=["area_id", "unknown"])
                writer.writeheader()
                writer.writerow({"area_id": "qiantan", "unknown": "value"})

            result = validate_csv_file("area_monthly_metrics", path)

        self.assertFalse(result.valid)
        messages = {(error.row, error.column, error.message) for error in result.errors}
        self.assertIn((0, "unknown", "unexpected header"), messages)
        self.assertIn((0, "month", "missing required header"), messages)

    def test_imports_valid_template_file_to_sqlite(self) -> None:
        with tempfile.TemporaryDirectory() as tmpdir:
            db_path = Path(tmpdir) / "research.sqlite"
            count = import_template_file(
                db_path,
                "policy_events",
                Path("docs/import_templates/policy_events.csv"),
            )
            with connect(db_path) as conn:
                rows = conn.execute("SELECT * FROM policy_events").fetchall()

        self.assertEqual(count, 1)
        self.assertEqual(len(rows), 1)
        self.assertEqual(rows[0]["level"], "shanghai")

    def test_fingerprints_import_file_without_local_path(self) -> None:
        fingerprint = fingerprint_file(Path("docs/import_templates/policy_events.csv"))

        self.assertEqual(fingerprint.original_filename, "policy_events.csv")
        self.assertEqual(len(fingerprint.sha256), 64)
        self.assertGreater(fingerprint.size_bytes, 0)
        self.assertTrue(fingerprint.raw_uri.startswith("raw://sha256/"))
        self.assertNotIn("/Users/", fingerprint.raw_uri)


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