"""回归测试: match_stats.available_at 回测防泄漏语义。

验证:
 1. _is_stats_available: available_at is None + cutoff 不为 None → 不可用
 2. _is_stats_available: available_at is None + cutoff is None(实盘) → 可用(兼容旧数据)
 3. _is_stats_available: available_at > cutoff → 不可用
 4. _is_stats_available: available_at <= cutoff → 可用
 5. 写入策略: available_at = match_date + 2h 缓冲
 6. cutoff 在缓冲内时不可用(available_at > cutoff → False)
"""
from __future__ import annotations

from datetime import datetime, timezone, timedelta
from unittest.mock import MagicMock

import pytest

from src.llm.context_builder import _is_stats_available


def _make_stats(available_at):
    s = MagicMock()
    s.available_at = available_at
    return s


class TestIsStatsAvailable:
    """_is_stats_available 回测防泄漏语义。"""

    def test_none_before_allows_none_available_at(self):
        """实盘模式(before=None): available_at 为 None 时允许(兼容旧数据)。"""
        stats = _make_stats(available_at=None)
        assert _is_stats_available(stats, before=None) is True

    def test_cutoff_with_none_available_at_is_unavailable(self):
        """回测模式(before=cutoff): available_at 为 None → 不可用(保守)。

        这是核心修复:防止无血缘时间的后期回填数据进入回测。
        """
        stats = _make_stats(available_at=None)
        cutoff = datetime(2026, 1, 13, 20, 0, tzinfo=timezone.utc)
        assert _is_stats_available(stats, before=cutoff) is False

    def test_available_at_after_cutoff_is_unavailable(self):
        """available_at 在 cutoff 之后 → 不可用。"""
        cutoff = datetime(2026, 1, 13, 20, 0, tzinfo=timezone.utc)
        stats = _make_stats(available_at=cutoff + timedelta(hours=1))
        assert _is_stats_available(stats, before=cutoff) is False

    def test_available_at_before_cutoff_is_available(self):
        """available_at 在 cutoff 之前 → 可用。"""
        cutoff = datetime(2026, 1, 13, 20, 0, tzinfo=timezone.utc)
        stats = _make_stats(available_at=cutoff - timedelta(hours=1))
        assert _is_stats_available(stats, before=cutoff) is True

    def test_available_at_equals_cutoff_is_available(self):
        """available_at == cutoff → 可用(边界包含)。"""
        cutoff = datetime(2026, 1, 13, 20, 0, tzinfo=timezone.utc)
        stats = _make_stats(available_at=cutoff)
        assert _is_stats_available(stats, before=cutoff) is True

    def test_real_world_scenario_backtest_avoids_future_data(self):
        """真实场景:回测时,赛后才生成的统计数据不应出现。

        比赛:2026-01-15 20:00
        cutoff(回测):2026-01-14 20:00(赛前 1 天)
        stats 在赛后才生成(available_at=2026-01-15 22:00)
        → 不可用
        """
        cutoff = datetime(2026, 1, 14, 20, 0, tzinfo=timezone.utc)
        stats = _make_stats(available_at=datetime(2026, 1, 15, 22, 0, tzinfo=timezone.utc))
        assert _is_stats_available(stats, before=cutoff) is False


class TestWriteBufferStrategy:
    """验证 bzzoiro/understat 写入 available_at 使用 match_date + 2h 缓冲。"""

    def test_bzzoirot_new_match_available_at_is_two_hours_after_kickoff(self):
        """bzzoiro 新建比赛时 available_at 应为开球 + 2 小时。"""
        import inspect
        from src.data import bzzoiro

        source = inspect.getsource(bzzoiro)
        # 验证:使用 timedelta(hours=2) 作为缓冲
        assert 'timedelta(hours=2)' in source, \
            "bzzoiro 应使用 match_date + timedelta(hours=2) 作为 available_at"

    def test_bzzoirot_existing_match_uses_two_hour_buffer(self):
        """bzzoiro 更新已有比赛时也应使用 2 小时缓冲。"""
        import inspect
        from src.data import bzzoiro

        source = inspect.getsource(bzzoiro)
        # 两处写入都应使用 timedelta(hours=2)
        count = source.count('timedelta(hours=2)')
        assert count >= 2, f"期望至少 2 处 timedelta(hours=2),实际 {count} 处"

    def test_understat_uses_two_hour_buffer(self):
        """understat 回填 xG 时也应使用 2 小时缓冲。"""
        import inspect
        from src.data import understat

        source = inspect.getsource(understat)
        assert 'timedelta(hours=2)' in source, \
            "understat 应使用 match_date + timedelta(hours=2) 作为 available_at"

    def test_cutoff_within_buffer_makes_stats_unavailable(self):
        """cutoff 在 2 小时缓冲内时,统计学不可用(回测防泄漏)。

        开球:2026-01-15 20:00
        available_at:2026-01-15 22:00(开球 + 2h)
        cutoff:2026-01-15 21:00(开赛后 1h, statistics 尚未可用)
        → 不可用
        """
        kickoff = datetime(2026, 1, 15, 20, 0, tzinfo=timezone.utc)
        available_at = kickoff + timedelta(hours=2)  # 22:00
        cutoff = kickoff + timedelta(hours=1)  # 21:00,在缓冲内

        stats = _make_stats(available_at=available_at)
        assert _is_stats_available(stats, before=cutoff) is False, \
            "cutoff 在 2h 缓冲内时应不可用(available_at > cutoff)"

    def test_cutoff_after_buffer_makes_stats_available(self):
        """cutoff 超过 2 小时缓冲后,统计变为可用。

        开球:2026-01-15 20:00
        available_at:2026-01-15 22:00(开球 + 2h)
        cutoff:2026-01-16 20:00(开赛后 1 天,超过缓冲)
        → 可用
        """
        kickoff = datetime(2026, 1, 15, 20, 0, tzinfo=timezone.utc)
        available_at = kickoff + timedelta(hours=2)  # 22:00
        cutoff = kickoff + timedelta(days=1)  # 2026-01-16 20:00

        stats = _make_stats(available_at=available_at)
        assert _is_stats_available(stats, before=cutoff) is True, \
            "cutoff 超过 2h 缓冲后应可用(available_at < cutoff)"