"""План полной замены применённой корректировки."""

import datetime
import uuid
from collections.abc import Sequence
from decimal import ROUND_HALF_UP, Decimal

from src.models.enums import CorrectionStatus, StatementType
from src.models.kfo import Correction
from src.schemas.corrections import CorrectionAggregateOut, CorrectionIn


def _optional_numeric(value: Decimal | None, precision: int, scale: int) -> Decimal | None:
    """Необязательные справочные поля старой модели не ограничивают сохранение.

    Полные значения остаются в вычисляемом DTO и аудите. Не подменяем выход за
    диапазон обрезкой.
    """
    limit = Decimal(10) ** (precision - scale)
    if value is None or abs(value) >= limit:
        return None
    rounded = value.quantize(Decimal(10) ** -scale, rounding=ROUND_HALF_UP)
    return rounded if abs(rounded) < limit else None


def correction_rows(  # noqa: PLR0913 - данные решения и автор сохранения
    aggregate: CorrectionAggregateOut,
    data: CorrectionIn,
    old: Sequence[Correction],
    *,
    version_id: uuid.UUID,
    statement_type: StatementType,
    user_id: uuid.UUID,
) -> tuple[list[Correction], list[Correction]]:
    now = datetime.datetime.now(datetime.UTC)
    revision = (aggregate.correction.version_no if aggregate.correction else 0) + 1
    roots: list[Correction] = []
    children: list[Correction] = []
    for debit, lines in ((True, data.debit), (False, data.credit)):
        if not lines:
            continue
        owner = aggregate.company_1.id if debit else aggregate.company_2.id
        other = aggregate.company_2.id if debit else aggregate.company_1.id
        previous = next((r for r in old if r.parent_correction_id is None and r.legal_entity_id == owner), None)
        root_id = previous.id if previous else uuid.uuid4()
        for index, line in enumerate(lines):
            row = previous if index == 0 and previous else Correction(id=root_id if index == 0 else uuid.uuid4())
            row.consolidation_version_id = version_id
            row.statement_type = statement_type
            row.rule_id = aggregate.rule_id
            row.parent_correction_id = None if index == 0 else root_id
            row.legal_entity_id, row.counterparty_id = owner, other
            row.debit_line_code = line.line_code if debit else None
            row.credit_line_code = None if debit else line.line_code
            row.debit_adjustment = Decimal(line.amount) if debit else None
            row.credit_adjustment = None if debit else Decimal(line.amount)
            row.debit_account_id = row.credit_account_id = None
            row.comment, row.reason_code = data.comment.strip(), data.reason_code
            row.deviation_amount = _optional_numeric(aggregate.deviation_amount, 18, 2)
            row.deviation_percent = _optional_numeric(aggregate.deviation_percent, 9, 4)
            row.status, row.version_no = CorrectionStatus.APPLIED, revision
            if row.created_at is None:
                row.created_by, row.created_at = user_id, now
            row.updated_by, row.updated_at = user_id, now
            (roots if index == 0 else children).append(row)
    return roots, children