import json
import os
from pathlib import Path


class IOSAIStorage:

    @staticmethod
    def _get_iosai_dir() -> Path:
        """获取 C:/Users/<用户名>/IOSAI/ 目录"""
        user_dir = Path.home()
        iosai_dir = user_dir / "IOSAI"
        iosai_dir.mkdir(parents=True, exist_ok=True)
        return iosai_dir


    @classmethod
    def save(cls, data: dict | list, filename: str = "data.json", mode: str = "overwrite") -> Path:
        file_path = cls._get_iosai_dir() / filename
        file_path.parent.mkdir(parents=True, exist_ok=True)

        def _load_json():
            try:
                return json.loads(file_path.read_text("utf-8"))
            except Exception:
                return {} if isinstance(data, dict) else []

        if mode == "merge" and isinstance(data, dict):
            old = _load_json()
            if not isinstance(old, dict):
                old = {}
            old.update(data)
            to_write = old
        elif mode == "append" and isinstance(data, list):
            old = _load_json()
            if not isinstance(old, list):
                old = []
            old.extend(data)
            to_write = old
        else:
            to_write = data  # 覆盖

        # 原子写入
        tmp = file_path.with_suffix(file_path.suffix + ".tmp")
        with open(tmp, "w", encoding="utf-8") as f:
            json.dump(to_write, f, ensure_ascii=False, indent=2)
        os.replace(tmp, file_path)
        print(f"[IOSAIStorage] 已写入: {file_path}")
        return file_path

    @classmethod
    def load(cls, filename: str = "data.json") -> dict | list | None:
        """
        从 C:/Users/<用户名>/IOSAI/filename 读取数据
        """
        file_path = cls._get_iosai_dir() / filename
        if not file_path.exists():
            print(f"[IOSAIStorage] 文件不存在: {file_path}")
            return {}

        try:
            with open(file_path, "r", encoding="utf-8") as f:
                return json.load(f)
        except Exception as e:
            print(f"[IOSAIStorage] 读取失败: {e}")
            return {}


    @classmethod
    def overwrite(cls, data: dict | list, filename: str = "data.json") -> Path:
        """
        强制覆盖写入数据到 C:/Users/<用户名>/IOSAI/filename
        （无论是否存在，都会写入）
        """
        file_path = cls._get_iosai_dir() / filename
        try:
            # "w" 模式本身就是覆盖，但这里单独做一个方法
            with open(file_path, "w", encoding="utf-8") as f:
                json.dump(data, f, ensure_ascii=False, indent=2)
            print(f"[IOSAIStorage] 已覆盖写入: {file_path}")
        except Exception as e:
            print(f"[IOSAIStorage] 覆盖失败: {e}")
        return file_path