from __future__ import annotations

from dataclasses import dataclass
from pathlib import Path
import os


@dataclass(frozen=True)
class AppConfig:
    env_path: Path | None
    feishu_app_id: str
    feishu_app_secret: str
    feishu_base_url: str
    feishu_app_token: str | None
    analytics_db_host: str
    analytics_db_port: str
    analytics_db_user: str
    analytics_db_password: str
    analytics_db_name: str


def load_env_file(env_path: Path) -> dict[str, str]:
    values: dict[str, str] = {}
    if not env_path.exists():
        return values

    for raw_line in env_path.read_text(encoding="utf-8").splitlines():
        line = raw_line.strip()
        if not line or line.startswith("#") or "=" not in line:
            continue
        key, value = line.split("=", 1)
        values[key.strip()] = value.strip().strip("'").strip('"')
    return values


def load_env_candidates() -> tuple[dict[str, str], Path | None]:
    script_path = Path(__file__).resolve()
    candidates = [
        script_path.parent.parent / ".env",
        script_path.parent.parent / "project (1)" / ".env",
        script_path.parent.parent.parent / ".env",
        Path.cwd() / ".env",
    ]
    seen: set[Path] = set()
    for candidate in candidates:
        candidate = candidate.resolve()
        if candidate in seen:
            continue
        seen.add(candidate)
        values = load_env_file(candidate)
        if values:
            return values, candidate
    return {}, None


def get_config(config: dict[str, str], *keys: str) -> str | None:
    for key in keys:
        value = config.get(key) or os.getenv(key)
        if value:
            return value
    return None


def require_config(config: dict[str, str], *keys: str) -> str:
    value = get_config(config, *keys)
    if value:
        return value
    raise KeyError(f"缺少必填配置: {' / '.join(keys)}")


def build_app_config() -> AppConfig:
    config, env_path = load_env_candidates()
    return AppConfig(
        env_path=env_path,
        feishu_app_id=require_config(config, "FEISHU_APP_ID", "APP_ID"),
        feishu_app_secret=require_config(config, "FEISHU_APP_SECRET", "FEISHU_APP_SECRE", "APP_SECRET"),
        feishu_base_url=require_config(config, "FEISHU_BASE_URL", "BASE_URL").rstrip("/"),
        feishu_app_token=get_config(config, "FEISHU_APP_TOKEN"),
        analytics_db_host=require_config(config, "ANALYTICS_DB_HOST"),
        analytics_db_port=require_config(config, "ANALYTICS_DB_PORT"),
        analytics_db_user=require_config(config, "ANALYTICS_DB_USER"),
        analytics_db_password=require_config(config, "ANALYTICS_DB_PASSWORD"),
        analytics_db_name=require_config(config, "ANALYTICS_DB_NAME"),
    )