"""Тарифы из tariffs.json."""

from __future__ import annotations

import json
import re
from dataclasses import dataclass
from pathlib import Path
from uuid import UUID

TARIFF_ID_RE = re.compile(r"^[A-Za-z0-9_]{2,40}$")


class TariffError(ValueError):
    pass


@dataclass(frozen=True, slots=True)
class Tariff:
    id: str
    title: str
    price: float
    days: int
    traffic_gb: float
    device_limit: int
    squad_uuids: tuple[UUID, ...]
    description: str = ""

    @property
    def traffic_bytes(self) -> float:
        # 0 или меньше → базовая квота 1000 ГБ
        from services.traffic import BASE_TRAFFIC_GB, gb_to_bytes

        gb = self.traffic_gb if self.traffic_gb > 0 else BASE_TRAFFIC_GB
        return gb_to_bytes(gb)

    def format_price(self) -> str:
        if self.price == int(self.price):
            return f"{int(self.price)} ₽"
        return f"{self.price:.2f} ₽"

    def to_dict(self) -> dict:
        return {
            "id": self.id,
            "title": self.title,
            "price": self.price if self.price != int(self.price) else int(self.price),
            "days": self.days,
            "traffic_gb": self.traffic_gb,
            "device_limit": self.device_limit,
            "squad_uuids": [str(u) for u in self.squad_uuids],
            "description": self.description,
        }

    def to_admin_dict(self) -> dict:
        d = self.to_dict()
        d["price_label"] = self.format_price()
        return d


def load_tariffs(path: str | Path) -> list[Tariff]:
    data = json.loads(Path(path).read_text(encoding="utf-8"))
    tariffs: list[Tariff] = []
    for item in data:
        tariffs.append(_tariff_from_item(item))
    return tariffs


def save_tariffs(path: str | Path, tariffs: list[Tariff]) -> None:
    payload = [t.to_dict() for t in tariffs]
    text = json.dumps(payload, ensure_ascii=False, indent=2) + "\n"
    Path(path).write_text(text, encoding="utf-8")


def replace_shared_tariffs(shared: list[Tariff], new: list[Tariff]) -> None:
    """Обновить общий список in-place (bot + webapp + workers)."""
    shared[:] = list(new)


def get_tariff(tariffs: list[Tariff], tariff_id: str) -> Tariff | None:
    for t in tariffs:
        if t.id == tariff_id:
            return t
    return None


def parse_tariff_payload(
    body: dict,
    *,
    existing: Tariff | None = None,
    default_squads: tuple[UUID, ...] = (),
) -> Tariff:
    tid = str(body.get("id") or (existing.id if existing else "")).strip()
    if not TARIFF_ID_RE.fullmatch(tid):
        raise TariffError("ID: 2–40 символов (латиница, цифры, _)")

    title = str(body.get("title") or (existing.title if existing else "")).strip()
    if not title:
        raise TariffError("Укажите название тарифа")
    if len(title) > 80:
        raise TariffError("Название слишком длинное")

    try:
        price = float(body.get("price") if "price" in body else (existing.price if existing else 0))
    except (TypeError, ValueError) as exc:
        raise TariffError("Некорректная цена") from exc
    if price < 0:
        raise TariffError("Цена не может быть отрицательной")

    try:
        days = int(body.get("days") if "days" in body else (existing.days if existing else 0))
    except (TypeError, ValueError) as exc:
        raise TariffError("Некорректное число дней") from exc
    if days < 1 or days > 3650:
        raise TariffError("Дни: от 1 до 3650")

    try:
        traffic_gb = float(
            body.get("traffic_gb")
            if "traffic_gb" in body
            else (existing.traffic_gb if existing else 1000)
        )
    except (TypeError, ValueError) as exc:
        raise TariffError("Некорректный трафик") from exc
    if traffic_gb < 0:
        raise TariffError("Трафик не может быть отрицательным")

    try:
        device_limit = int(
            body.get("device_limit")
            if "device_limit" in body
            else (existing.device_limit if existing else 10)
        )
    except (TypeError, ValueError) as exc:
        raise TariffError("Некорректный лимит устройств") from exc
    if device_limit < 1 or device_limit > 100:
        raise TariffError("Устройства: от 1 до 100")

    if "squad_uuids" in body:
        squads_raw = body.get("squad_uuids")
        if isinstance(squads_raw, str):
            parts = [p.strip() for p in squads_raw.replace(";", ",").split(",") if p.strip()]
        elif isinstance(squads_raw, list):
            parts = [str(x).strip() for x in squads_raw if str(x).strip()]
        else:
            parts = []
        try:
            squad_uuids = tuple(UUID(p) for p in parts)
        except ValueError as exc:
            raise TariffError("Некорректный UUID в squad_uuids") from exc
    elif existing:
        squad_uuids = existing.squad_uuids
    else:
        squad_uuids = default_squads

    if not squad_uuids:
        raise TariffError("Нужен хотя бы один squad UUID")

    description = str(
        body.get("description")
        if "description" in body
        else (existing.description if existing else "")
    ).strip()
    if len(description) > 300:
        raise TariffError("Описание слишком длинное")

    return Tariff(
        id=tid,
        title=title,
        price=price,
        days=days,
        traffic_gb=traffic_gb,
        device_limit=device_limit,
        squad_uuids=squad_uuids,
        description=description,
    )


def _tariff_from_item(item: dict) -> Tariff:
    return Tariff(
        id=str(item["id"]),
        title=str(item["title"]),
        price=float(item["price"]),
        days=int(item["days"]),
        traffic_gb=float(item.get("traffic_gb") or 0),
        device_limit=int(item.get("device_limit") or 1),
        squad_uuids=tuple(UUID(str(u)) for u in item.get("squad_uuids") or []),
        description=str(item.get("description") or ""),
    )