from __future__ import annotations

from pathlib import Path

from pydantic import field_validator
from pydantic_settings import BaseSettings, SettingsConfigDict

BASE_DIR = Path(__file__).resolve().parent.parent


class ApiSettings(BaseSettings):
    model_config = SettingsConfigDict(
        env_file=BASE_DIR / ".env",
        env_file_encoding="utf-8",
        extra="ignore",
    )

    database_path: Path = BASE_DIR / "data" / "budget.db"
    bot_token: str
    # Shared secret for bot (/api/auth/internal) and admin /api/budgets/*
    api_token: str | None = None
    jwt_secret: str | None = None
    jwt_ttl_seconds: int = 60 * 60 * 24 * 14
    telegram_auth_max_age_seconds: int = 60 * 60 * 24
    cors_origins: str = "*"
    host: str = "0.0.0.0"
    port: int = 8000

    @field_validator("bot_token", mode="before")
    @classmethod
    def require_bot_token(cls, value: object) -> object:
        if value is None or (isinstance(value, str) and not value.strip()):
            raise ValueError("BOT_TOKEN is required for Telegram login")
        return value

    @field_validator("api_token", "jwt_secret", mode="before")
    @classmethod
    def empty_as_none(cls, value: object) -> object:
        if isinstance(value, str) and not value.strip():
            return None
        return value

    @property
    def session_secret(self) -> str:
        return self.jwt_secret or f"ppm-jwt::{self.bot_token}"

    @property
    def cors_origin_list(self) -> list[str]:
        return [item.strip() for item in self.cors_origins.split(",") if item.strip()]


settings = ApiSettings()