"""T-6 交易日历纯函数单测（R-5 · 开发计划 T-6）。

**不依赖 DB**：日历以谓词注入（`is_open: Callable[[date], bool]`），
用一个内存日期集合构造，穷举边界（周末/长假/截点/顺延）。

覆盖：
1. `is_biz_day` 谓词透传
2. `next_biz_day` 跨周末/跨长假；找不到 → ValueError
3. `previous_biz_day` 反向
4. `before_cutoff` 严格小于（15:00:00 整视为超时）
5. `resolve_accept_date` 四种组合（交易日/非交易日 × 截点前/后）
6. `parse_cutoff` 合法两式 + 非法格式/越界报错
"""

from __future__ import annotations

from datetime import date, datetime, time

import pytest

from app.service.convert import trading_calendar as tc


def _cal(open_dates: set[date]):
    """构造日历谓词（闭包，仅命中集合内日期）。"""
    return lambda d: d in open_dates


#: 2026-09 交易日（周一~周五，剔除 9/6 周末等；手工枚举，与断言自洽）
SEP = {
    date(2026, 9, 1), date(2026, 9, 2), date(2026, 9, 3), date(2026, 9, 4),
    date(2026, 9, 7), date(2026, 9, 8), date(2026, 9, 9), date(2026, 9, 10),
    date(2026, 9, 11),
}


# ── 1. is_biz_day ─────────────────────────────────────────────────────

def test_is_biz_day_passthrough():
    cal = _cal(SEP)
    assert tc.is_biz_day(date(2026, 9, 9), cal) is True
    assert tc.is_biz_day(date(2026, 9, 5), cal) is False  # 周六（不在集合）


# ── 2. next_biz_day ───────────────────────────────────────────────────

def test_next_biz_day_within_week():
    cal = _cal(SEP)
    # 周中 → 次日
    assert tc.next_biz_day(date(2026, 9, 8), cal) == date(2026, 9, 9)


def test_next_biz_day_crosses_weekend():
    cal = _cal(SEP)
    # 周五 9/4 → 下周一 9/7（跳过 9/5 周六 / 9/6 周日）
    assert tc.next_biz_day(date(2026, 9, 4), cal) == date(2026, 9, 7)


def test_next_biz_day_crosses_long_holiday():
    """跨长假：9/30 → 10/9（国庆 10/1~10/8 连休，全部不在集合）。"""
    holiday = {date(2026, 9, 30), date(2026, 10, 9), date(2026, 10, 12)}
    cal = _cal(holiday)
    assert tc.next_biz_day(date(2026, 9, 30), cal) == date(2026, 10, 9)


def test_next_biz_day_not_found_raises():
    cal = _cal(set())  # 空日历
    with pytest.raises(ValueError, match="未找到交易日"):
        tc.next_biz_day(date(2026, 9, 9), cal)


# ── 3. previous_biz_day ───────────────────────────────────────────────

def test_previous_biz_day_crosses_weekend():
    cal = _cal(SEP)
    # 周一 9/7 → 上周五 9/4
    assert tc.previous_biz_day(date(2026, 9, 7), cal) == date(2026, 9, 4)


def test_previous_biz_day_not_found_raises():
    cal = _cal(set())
    with pytest.raises(ValueError, match="未找到交易日"):
        tc.previous_biz_day(date(2026, 9, 9), cal)


# ── 4. before_cutoff ──────────────────────────────────────────────────

def test_before_cutoff_strict_less_than():
    cutoff = time(15, 0)
    assert tc.before_cutoff(datetime(2026, 9, 9, 14, 59, 59), cutoff) is True
    # 15:00:00 整 → False（严格小于，超时边界）
    assert tc.before_cutoff(datetime(2026, 9, 9, 15, 0, 0), cutoff) is False
    assert tc.before_cutoff(datetime(2026, 9, 9, 15, 0, 1), cutoff) is False
    assert tc.before_cutoff(datetime(2026, 9, 9, 9, 30), cutoff) is True


def test_before_cutoff_default_is_1500():
    assert tc.before_cutoff(datetime(2026, 9, 9, 14, 0)) is True
    assert tc.before_cutoff(datetime(2026, 9, 9, 16, 0)) is False


# ── 5. resolve_accept_date ────────────────────────────────────────────

def test_resolve_accept_date_biz_day_before_cutoff():
    """交易日 + 截点前 → 当日 T。"""
    cal = _cal(SEP)
    got = tc.resolve_accept_date(datetime(2026, 9, 9, 10, 12), cal)
    assert got == date(2026, 9, 9)


def test_resolve_accept_date_biz_day_after_cutoff():
    """交易日 + 过截点 → 下一交易日。"""
    cal = _cal(SEP)
    got = tc.resolve_accept_date(datetime(2026, 9, 9, 15, 30), cal)
    assert got == date(2026, 9, 10)


def test_resolve_accept_date_non_biz_day():
    """非交易日（周六）→ 下一交易日（下周一）。"""
    cal = _cal(SEP)
    got = tc.resolve_accept_date(datetime(2026, 9, 5, 10, 0), cal)
    assert got == date(2026, 9, 7)


def test_resolve_accept_date_friday_after_cutoff():
    """周五过截点 → 下周一（跨周末）。"""
    cal = _cal(SEP)
    got = tc.resolve_accept_date(datetime(2026, 9, 4, 16, 0), cal)
    assert got == date(2026, 9, 7)


def test_resolve_accept_date_custom_cutoff():
    """截点可配置（B1：值取自 settings.convert_cutoff_time）。"""
    cal = _cal(SEP)
    # 截点 12:00 时，14:00 提交 → 顺延次日
    got = tc.resolve_accept_date(datetime(2026, 9, 9, 14, 0), cal, cutoff=time(12, 0))
    assert got == date(2026, 9, 10)


# ── 6. parse_cutoff ───────────────────────────────────────────────────

def test_parse_cutoff_forms():
    assert tc.parse_cutoff("15:00") == time(15, 0)
    assert tc.parse_cutoff("15:00:00") == time(15, 0, 0)
    assert tc.parse_cutoff(" 14:30 ") == time(14, 30)  # 容忍空白


def test_parse_cutoff_invalid_format():
    for bad in ("", "15", "15:00:00:00", "abc"):
        with pytest.raises(ValueError):
            tc.parse_cutoff(bad)


def test_parse_cutoff_out_of_range():
    for bad in ("25:00", "12:99"):
        with pytest.raises(ValueError):
            tc.parse_cutoff(bad)