"""Период консолидации (Срез 4): отчётная дата (OQ-40) и выбор источников ОСВ на пару (ЮЛ, счёт) — D-2, §2."""

import datetime
import uuid
from dataclasses import dataclass

import pytest

from src.domain.consolidation_periods import (
    QUARTER_ORDER,
    Gap,
    Sources,
    counts_as_cumulative,
    effective_cumulative,
    quarters_through,
    reporting_date,
    select_sources,
)
from src.models.enums import PeriodQuarter

Q1, Q2, Q3, Q4 = PeriodQuarter.Q1, PeriodQuarter.Q2, PeriodQuarter.Q3, PeriodQuarter.Q4


@pytest.mark.parametrize(
    ("year", "quarter", "expected"),
    [
        (2024, PeriodQuarter.Q1, datetime.date(2024, 4, 1)),
        (2024, PeriodQuarter.Q2, datetime.date(2024, 7, 1)),
        (2024, PeriodQuarter.Q3, datetime.date(2024, 10, 1)),
        (2024, PeriodQuarter.Q4, datetime.date(2025, 1, 1)),
        (2100, PeriodQuarter.Q4, datetime.date(2101, 1, 1)),
    ],
)
def test_reporting_date_is_first_day_after_quarter(year: int, quarter: PeriodQuarter, expected: datetime.date) -> None:
    assert reporting_date(year, quarter) == expected


@dataclass(frozen=True)
class _Doc:
    """Документ для `select_sources`: структурно подходит под `DocLike` (как `Document` и `SourceDocument`)."""

    period_quarter: PeriodQuarter | None
    is_cumulative: bool | None
    id: uuid.UUID = uuid.UUID(int=0)


def _doc(quarter: PeriodQuarter | None, cumulative: bool | None = False) -> _Doc:
    return _Doc(quarter, cumulative, uuid.uuid4())


def test_quarter_order_and_quarters_through() -> None:
    assert QUARTER_ORDER == (Q1, Q2, Q3, Q4)
    assert quarters_through(Q1) == (Q1,)
    assert quarters_through(Q3) == (Q1, Q2, Q3)
    assert quarters_through(Q4) == QUARTER_ORDER


def test_counts_as_cumulative_null_is_cumulative() -> None:
    """R-1, решение №10: NULL (ББ/ОФР) — нарастающий; только `False` — квартальный."""
    assert counts_as_cumulative(True) is True
    assert counts_as_cumulative(None) is True
    assert counts_as_cumulative(False) is False


def test_cumulative_of_version_quarter_is_single_source() -> None:
    cumulative = _doc(Q3, True)
    assert select_sources(Q3, [cumulative]) == Sources(documents=(cumulative,), cumulative=True)


def test_null_cumulative_flag_of_version_quarter_counts_as_cumulative() -> None:
    document = _doc(Q3, None)
    assert select_sources(Q3, [document]) == Sources(documents=(document,), cumulative=True)


def test_quarterly_q1_to_q3_are_sources_in_quarter_order() -> None:
    q1, q2, q3 = _doc(Q1), _doc(Q2), _doc(Q3)
    assert select_sources(Q3, [q3, q1, q2]) == Sources(documents=(q1, q2, q3), cumulative=False)


def test_missing_middle_quarter_is_gap() -> None:
    assert select_sources(Q3, [_doc(Q1), _doc(Q3)]) == Gap(missing_quarters=(Q2,))


def test_q1_version_quarterly_q1_is_enough() -> None:
    """Для версии Q1 квартальный Q1 равнозначен нарастающему: источник есть, пробела нет."""
    q1 = _doc(Q1)
    assert select_sources(Q1, [q1]) == Sources(documents=(q1,), cumulative=False)


def test_cumulative_beats_quarterly_of_same_pair() -> None:
    """Review Focus 2: квартальные Q1–Q3 и нарастающий Q3 — источник один, нарастающий."""
    cumulative = _doc(Q3, True)
    assert select_sources(Q3, [_doc(Q1), _doc(Q2), _doc(Q3), cumulative]) == Sources((cumulative,), cumulative=True)


def test_cumulative_beats_quarterly_with_gap() -> None:
    cumulative = _doc(Q3, True)
    assert select_sources(Q3, [_doc(Q1), cumulative]) == Sources((cumulative,), cumulative=True)


def test_cumulative_of_earlier_quarter_is_ignored() -> None:
    """Review Focus 2 (защитно): нарастающий Q2 при версии Q3 не привязывается, но и функция его не берёт."""
    assert select_sources(Q3, [_doc(Q2, True)]) == Gap(missing_quarters=(Q1, Q2, Q3))


def test_cumulative_of_earlier_quarter_does_not_fill_gap_of_quarterly() -> None:
    assert select_sources(Q3, [_doc(Q1), _doc(Q2, True), _doc(Q3)]) == Gap(missing_quarters=(Q2,))


def test_quarterly_after_version_and_without_quarter_are_ignored() -> None:
    q1, q2, q3 = _doc(Q1), _doc(Q2), _doc(Q3)
    assert select_sources(Q3, [q1, q2, q3, _doc(Q4), _doc(None), _doc(None, True)]) == Sources((q1, q2, q3), False)
    assert select_sources(Q2, [_doc(Q3)]) == Gap(missing_quarters=(Q1, Q2))


def test_no_documents_is_gap_of_all_quarters() -> None:
    assert select_sources(Q3, []) == Gap(missing_quarters=(Q1, Q2, Q3))
    assert select_sources(Q1, []) == Gap(missing_quarters=(Q1,))


# ------------------------------------------------------------------------- R-14: документ за Q1 равнозначен обоим видам


@pytest.mark.parametrize(
    ("flag", "quarter", "expected"),
    [
        (True, Q1, False),  # нарастающий с начала года за Q1 — это и есть квартал Q1
        (None, Q1, False),
        (False, Q1, False),
        (True, Q2, True),
        (None, Q3, True),  # ББ/ОФР вне Q1 — нарастающие (решение №10)
        (False, Q3, False),
        (True, None, True),  # квартал не определён — по флагу (такой документ не привязывается)
    ],
)
def test_effective_cumulative(flag: bool | None, quarter: PeriodQuarter | None, expected: bool) -> None:
    assert effective_cumulative(flag, quarter) is expected


def test_cumulative_q1_is_quarterly_q1_source_for_later_version() -> None:
    """Фикстуры РБ: парсер помечает ОСВ за Q1 нарастающей, Q2/Q3 — квартальными; для версии Q3 это полный комплект."""
    q1, q2, q3 = _doc(Q1, True), _doc(Q2), _doc(Q3)
    assert select_sources(Q3, [q3, q2, q1]) == Sources(documents=(q1, q2, q3), cumulative=False)
    assert select_sources(Q2, [q2, q1]) == Sources(documents=(q1, q2), cumulative=False)


def test_null_flag_q1_is_quarterly_q1_source_for_later_version() -> None:
    q1, q2 = _doc(Q1, None), _doc(Q2)
    assert select_sources(Q2, [q1, q2]) == Sources(documents=(q1, q2), cumulative=False)


def test_cumulative_q1_does_not_fill_other_quarters() -> None:
    assert select_sources(Q2, [_doc(Q1, True)]) == Gap(missing_quarters=(Q2,))
    # нарастающий Q2 при версии Q3 — не квартальный Q2: не хватает квартальных Q2 и Q3
    assert select_sources(Q3, [_doc(Q1, True), _doc(Q2, True)]) == Gap(missing_quarters=(Q2, Q3))


def test_cumulative_of_version_quarter_still_beats_cumulative_q1() -> None:
    cumulative = _doc(Q3, True)
    assert select_sources(Q3, [_doc(Q1, True), _doc(Q2), _doc(Q3), cumulative]) == Sources((cumulative,), True)


def test_q1_version_cumulative_q1_is_taken_as_is() -> None:
    """Версия Q1: нарастающий Q1 — источник «как есть» (решение №50), квартальный — склейка из одного квартала."""
    cumulative, quarterly = _doc(Q1, True), _doc(Q1, False)
    assert select_sources(Q1, [cumulative]) == Sources((cumulative,), cumulative=True)
    assert select_sources(Q1, [quarterly, cumulative]) == Sources((cumulative,), cumulative=True)
    assert select_sources(Q1, [quarterly]) == Sources((quarterly,), cumulative=False)