import os
import sys

# 1. 处理读取库
try:
    import tomllib as toml_read  # Python 3.11+
except ImportError:
    try:
        import tomli as toml_read
    except ImportError:
        print("错误: 缺少 TOML 读取库。请运行: pip install tomli")
        sys.exit(1)

# 2. 处理写入库 (必须安装 pip install tomli-w)
try:
    import tomli_w as toml_write
except ImportError:
    # 如果没安装，提供一个 fallback 提示
    toml_write = None


def get_base_dir():
    if getattr(sys, "frozen", False):
        return os.path.dirname(sys.executable)
    else:
        # 假设当前文件在项目根目录或根目录下的某个文件夹中
        return os.path.dirname(os.path.dirname(os.path.abspath(__file__)))


def get_resource_path(relative_path):
    base_path = get_base_dir()
    external_path = os.path.join(base_path, relative_path)
    if os.path.exists(external_path):
        return external_path
    if getattr(sys, "frozen", False):
        internal_path = os.path.join(sys._MEIPASS, relative_path)
        if os.path.exists(internal_path):
            return internal_path
    return external_path


# ==========================================
# 1. 配置加载 (Config Loader)
# ==========================================
def load_config(config_filename="config.toml"):
    config_path = get_resource_path(config_filename)

    if not os.path.exists(config_path):
        # 如果彻底找不到，返回一个最小化的默认值，防止程序奔溃
        return {"source_file": "", "ai": {"api_key": ""}, "teachers": []}

    try:
        with open(config_path, "rb") as f:
            data = toml_read.load(f)

        base_dir = get_base_dir()

        # 使用 .get() 安全获取，防止 KeyError: 'paths'
        paths = data.get("paths", {})
        class_info = data.get("class_info", {})
        defaults = data.get("defaults", {})

        config = {
            "root_path": base_dir,
            "data_folder": os.path.join(os.path.join("data")),
            # 扁平化映射
            "source_file": get_resource_path(
                os.path.join("templates", paths.get("source_file", ""))
            ),
            "excel_file": get_resource_path(
                os.path.join("data", paths.get("excel_file", ""))
            ),
            "image_folder": get_resource_path(
                os.path.join("data", paths.get("image_folder", ""))
            ),
            "fonts_dir": get_resource_path(paths.get("fonts_dir", "fonts")),
            "output_folder": os.path.join(
                base_dir, paths.get("output_folder", "output")
            ),
            "signature_image": get_resource_path(
                os.path.join("data", paths.get("signature_image", "signature.png"))
            ),
            "class_name": class_info.get("class_name", "未命名班级"),
            "teachers": class_info.get("teachers", []),
            "class_type": class_info.get("class_type", 0),
            "default_comment": defaults.get("default_comment", "暂无评语"),
            "age_group": defaults.get("age_group", "大班上学期"),
            "ai": data.get(
                "ai", {"api_key": "", "api_url": "", "model": "", "prompt": ""}
            ),
        }
        return config

    except Exception as e:
        print(f"解析配置文件失败: {e}")
        return {}


# ==========================================
# 2. 配置保存 (Config Saver)
# ==========================================
def save_config(config_data, config_filename="config.toml"):
    if not toml_write:
        return False, "未安装 tomli-w 库，无法保存。请运行 pip install tomli-w"

    base_path = get_base_dir()
    save_path = os.path.join(base_path, config_filename)

    try:
        # 将扁平化的数据重新打包成嵌套结构，以适配 load_config 的读取逻辑
        new_data = {
            "paths": {
                "source_file": os.path.basename(config_data.get("source_file", "")),
                "output_folder": os.path.basename(
                    config_data.get("output_folder", "output")
                ),
                "excel_file": os.path.basename(config_data.get("excel_file", "")),
                "image_folder": os.path.basename(config_data.get("image_folder", "")),
                "fonts_dir": os.path.basename(config_data.get("fonts_dir", "fonts")),
                "signature_image": get_resource_path(
                    os.path.join(
                        "data", config_data.get("signature_image", "signature.png")
                    )
                ),
            },
            "class_info": {
                "class_name": config_data.get("class_name", ""),
                "teachers": config_data.get("teachers", []),
                "class_type": config_data.get("class_type", 0),
            },
            "defaults": {
                "default_comment": config_data.get("default_comment", ""),
                "age_group": config_data.get("age_group", ""),
            },
            "ai": config_data.get("ai", {}),
        }

        # 写入文件
        with open(save_path, "wb") as f:
            f.write(toml_write.dumps(new_data).encode("utf-8"))

        return True, f"成功保存到: {save_path}"

    except Exception as e:
        return False, f"写入失败: {str(e)}"