"""历史时区 / 夏令时黄金样本（设计文档 §4.3 / §6.1 C 组）。

逐条读 golden/history_tz.yaml，断言 to_utc 返回的 (utc, audit)：
  - tz_used / is_dst / dst_offset_min / source：audit 字段逐项相等
  - utc_offset_min：钟表时间 − UTC（分钟），验证 UTC 解算本身
"""
import sys
import unittest
from datetime import datetime
from pathlib import Path

import yaml

SKILL_ROOT = Path(__file__).resolve().parents[1]
SCRIPTS_DIR = SKILL_ROOT / "scripts"
GOLDEN_DIR = Path(__file__).resolve().parent / "golden"
if str(SCRIPTS_DIR) not in sys.path:
    sys.path.insert(0, str(SCRIPTS_DIR))

from astro.timezone_resolve import to_utc   # noqa: E402
from geo.cities import resolve_location     # noqa: E402

AUDIT_KEYS = ("tz_used", "is_dst", "dst_offset_min", "source")


class HistoryTzGoldenTest(unittest.TestCase):
    def test_history_tz_yaml(self):
        with open(GOLDEN_DIR / "history_tz.yaml", encoding="utf-8") as f:
            samples = yaml.safe_load(f)
        self.assertGreaterEqual(len(samples), 4, "history_tz.yaml 应有 4 条样本")
        for s in samples:
            with self.subTest(sample=s["name"], place=s["place"]):
                loc = resolve_location(s["place"])
                clock = datetime.strptime(s["birth"], "%Y-%m-%d %H:%M")
                utc, audit = to_utc(clock, loc)
                expect = s["expect"]
                for key in AUDIT_KEYS:
                    if key in expect:
                        self.assertEqual(
                            audit[key], expect[key], f"audit[{key!r}] 不符"
                        )
                if "utc_offset_min" in expect:
                    offset_min = (
                        clock - utc.replace(tzinfo=None)
                    ).total_seconds() / 60
                    self.assertAlmostEqual(
                        offset_min, expect["utc_offset_min"], delta=0.5,
                        msg=f"UTC 偏移 {offset_min} 分 ≠ 期望 "
                            f"{expect['utc_offset_min']} 分",
                    )


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