"""Вложения партии (фото). Файлы — на томе settings.upload_dir, в БД метаданные.

Общий сервис для игрового и админского путей (роутеры лишь строят URL с нужным префиксом).
"""
from __future__ import annotations

import shutil
from pathlib import Path

from sqlmodel import Session, select

from app.core.config import settings
from app.core.errors import ConflictError, NotFoundError
from app.models import Match, MatchAttachment, User

MAX_ATTACHMENTS = 10
_SUBDIR = "matches"


def list_for_match(session: Session, match_id: int) -> list[MatchAttachment]:
    return list(
        session.exec(
            select(MatchAttachment)
            .where(MatchAttachment.match_id == match_id)
            .order_by(MatchAttachment.created_at, MatchAttachment.id)
        ).all()
    )


def count(session: Session, match_id: int) -> int:
    return len(
        session.exec(
            select(MatchAttachment.id).where(MatchAttachment.match_id == match_id)
        ).all()
    )


def file_path(att: MatchAttachment) -> Path:
    return Path(settings.upload_dir) / att.storage_path


def add_photo(
    session: Session, match: Match, user: User, content: bytes, ext: str, mime: str
) -> MatchAttachment:
    if count(session, match.id) >= MAX_ATTACHMENTS:  # type: ignore[arg-type]
        raise ConflictError(f"Можно прикрепить не более {MAX_ATTACHMENTS} файлов.")
    att = MatchAttachment(
        match_id=match.id,  # type: ignore[arg-type]
        uploaded_by=user.id,
        kind="photo",
        storage_path="",
        mime_type=mime,
        size_bytes=len(content),
    )
    session.add(att)
    session.flush()  # получаем id для имени файла
    rel = f"{_SUBDIR}/{match.id}/{att.id}.{ext}"
    abs_path = Path(settings.upload_dir) / rel
    abs_path.parent.mkdir(parents=True, exist_ok=True)
    abs_path.write_bytes(content)
    att.storage_path = rel
    session.add(att)
    session.commit()
    session.refresh(att)
    return att


def get_for_match(session: Session, match_id: int, att_id: int) -> MatchAttachment:
    att = session.get(MatchAttachment, att_id)
    if att is None or att.match_id != match_id:
        raise NotFoundError("Вложение не найдено.")
    return att


def delete(session: Session, match: Match, att_id: int) -> None:
    att = get_for_match(session, match.id, att_id)  # type: ignore[arg-type]
    path = file_path(att)
    if path.exists():
        try:
            path.unlink()
        except OSError:
            pass
    session.delete(att)
    session.commit()


def delete_match_files(match_id: int) -> None:
    """Удалить всю папку медиа партии (при удалении партии; строки БД уйдут каскадом)."""
    folder = Path(settings.upload_dir) / _SUBDIR / str(match_id)
    if folder.is_dir():
        shutil.rmtree(folder, ignore_errors=True)