import os
from dataclasses import dataclass
from functools import lru_cache
from pathlib import Path
from typing import Optional

from dotenv import load_dotenv


BASE_DIR = Path(__file__).resolve().parents[1]
DOTENV_PATH = BASE_DIR / ".env"

if DOTENV_PATH.exists():
    load_dotenv(DOTENV_PATH)


@dataclass
class Settings:
    telegram_api_id: int
    telegram_api_hash: str
    telegram_session_path: str
    telegram_bot_username: str
    telegram_bot_token: Optional[str]

    host: str
    port: int

    enable_pagination: bool
    pagination_max_pages: int
    pagination_delay: float
    pagination_timeout: float
    pagination_keywords: list[str]

    database_url: str

    remote_upload_enabled: bool
    remote_ssh_host: str
    remote_ssh_user: str
    remote_ssh_password: str
    remote_ssh_target: str
    remote_upload_interval: int
    remote_upload_batch_size: int

    def __post_init__(self):
        if not self.database_url:
            raise ValueError("DATABASE_URL 未配置，无法初始化数据库连接")


def _env_bool(name: str, default: bool = False) -> bool:
    return os.getenv(name, str(default)).strip().lower() in ("1", "true", "yes", "on")


def _env_int(name: str, default: int) -> int:
    try:
        return int(os.getenv(name, str(default)))
    except ValueError:
        return default


def _env_float(name: str, default: float) -> float:
    try:
        return float(os.getenv(name, str(default)))
    except ValueError:
        return default


@lru_cache()
def get_settings() -> Settings:
    keywords = os.getenv(
        "FUNSTAT_PAGINATION_KEYWORDS",
        "➡️,下一页,Next,更多,下页,›,>>"
    )

    return Settings(
        telegram_api_id=_env_int("TELEGRAM_API_ID", 24660516),
        telegram_api_hash=os.getenv("TELEGRAM_API_HASH", "eae564578880a59c9963916ff1bbbd3a"),
        telegram_session_path=os.getenv(
            "TELEGRAM_SESSION_PATH",
            str(Path.home() / "telegram_sessions" / "funstat_bot")
        ),
        telegram_bot_username=os.getenv("TELEGRAM_BOT_USERNAME", "@ktqiangda_bot"),
        telegram_bot_token=os.getenv("TELEGRAM_BOT_TOKEN"),
        host=os.getenv("FUNSTAT_HOST", "127.0.0.1"),
        port=_env_int("FUNSTAT_PORT", 8094),
        enable_pagination=_env_bool("FUNSTAT_ENABLE_PAGINATION", True),
        pagination_max_pages=_env_int("FUNSTAT_PAGINATION_MAX_PAGES", 10),
        pagination_delay=_env_float("FUNSTAT_PAGINATION_DELAY", 2.0),
        pagination_timeout=_env_float("FUNSTAT_PAGINATION_TIMEOUT", 8.0),
        pagination_keywords=[
            kw.strip() for kw in keywords.split(",") if kw.strip()
        ],
        database_url=os.getenv(
            "DATABASE_URL",
            "postgresql://funstat:funstat_dev_password@127.0.0.1:5433/funstat"
        ),
        remote_upload_enabled=_env_bool("REMOTE_UPLOAD_ENABLED", True),
        remote_ssh_host=os.getenv("REMOTE_SSH_HOST", ""),
        remote_ssh_user=os.getenv("REMOTE_SSH_USER", ""),
        remote_ssh_password=os.getenv("REMOTE_SSH_PASSWORD", ""),
        remote_ssh_target=os.getenv("REMOTE_SSH_TARGET", "/home/atai/funstat_data/inbox"),
        remote_upload_interval=_env_int("REMOTE_UPLOAD_INTERVAL", 120),
        remote_upload_batch_size=_env_int("REMOTE_UPLOAD_BATCH_SIZE", 200),
    )