from __future__ import annotations

import json
import os
from dataclasses import dataclass, field
from pathlib import Path
from typing import Any

ROOT = Path(__file__).resolve().parents[1]
DEFAULT_DB_PATH = Path(os.environ.get("DATAHUB_DB_PATH") or (ROOT / "data" / "datahub.db"))
DEFAULT_BACKUP_DIR = Path(os.environ.get("DATAHUB_BACKUP_DIR") or (ROOT / "data" / "backups"))
DEFAULT_CONFIG_PATH = ROOT / "config" / "hub-quality.config.json"


def _load_quality(path: Path) -> dict[str, Any]:
    if not path.is_file():
        return {}
    return json.loads(path.read_text(encoding="utf-8"))


@dataclass
class Settings:
    host: str = "127.0.0.1"
    port: int = 8766
    encryption_key: str = ""
    api_token: str = ""
    admin_password: str = ""
    tushare_token: str = ""
    db_path: Path = DEFAULT_DB_PATH
    backup_dir: Path = DEFAULT_BACKUP_DIR
    quality: dict[str, Any] = field(default_factory=dict)
    log_level: str = "INFO"
    scheduler_enabled: bool = True

    @property
    def tushare_rate_per_minute(self) -> int:
        return int(self.quality.get("tushare_rate_per_minute") or 300)

    @property
    def max_publish_attempts(self) -> int:
        return int(self.quality.get("max_publish_attempts") or 5)

    @property
    def list_limit_default(self) -> int:
        return int(self.quality.get("list_limit_default") or 5000)

    @property
    def list_limit_max(self) -> int:
        return int(self.quality.get("list_limit_max") or 5000)

    @property
    def calendar_start(self) -> str:
        return str(self.quality.get("calendar_start") or "20160101")

    @property
    def index_history_trading_days(self) -> int:
        return int(self.quality.get("index_history_trading_days") or 260)


def load_settings(
    env: dict[str, str] | None = None,
    config_path: Path | None = None,
) -> Settings:
    environ = env if env is not None else dict(os.environ)
    quality_path = config_path or DEFAULT_CONFIG_PATH
    db_path = Path(environ.get("DATAHUB_DB_PATH") or DEFAULT_DB_PATH)
    backup_dir = Path(environ.get("DATAHUB_BACKUP_DIR") or DEFAULT_BACKUP_DIR)
    return Settings(
        host=environ.get("DATAHUB_HOST") or "127.0.0.1",
        port=int(environ.get("DATAHUB_PORT") or 8766),
        encryption_key=str(environ.get("DATAHUB_ENCRYPTION_KEY") or "").strip(),
        api_token=str(environ.get("DATAHUB_TOKEN") or "").strip(),
        admin_password=str(environ.get("DATAHUB_ADMIN_PASSWORD") or "").strip(),
        tushare_token=str(environ.get("TUSHARE_TOKEN") or "").strip(),
        db_path=db_path,
        backup_dir=backup_dir,
        quality=_load_quality(quality_path),
        log_level=environ.get("DATAHUB_LOG_LEVEL") or "INFO",
        scheduler_enabled=str(environ.get("DATAHUB_SCHEDULER") or "1") not in {"0", "false", "False"},
    )