certflow.config.config_center_backend 源代码

"""配置中心后端（T10）：统一「基础层 + 覆盖层」读写。

见 docs/discussions/resource-paths-audit.md §11.3。供配置中心 UI（T13）与
``settings_ui.yaml`` spec 驱动。基础实现复用现有 ``paths_override``（``paths.local.yaml``
覆盖层）+ ``settings.merge_user_config``（userconfig 增量写），不重建配置模型。

分层落盘规则：
  - layer=override / base -> 写 ``paths.local.yaml``（gitignored，不污染仓库/状态文件）
  - layer=userconfig      -> 写 ``userconfig.yaml``（按顶层键归属自动分流到桶2/桶3）
"""

from __future__ import annotations

from typing import Any

from certflow.config.paths_override import (
    _get_nested,
    list_path_overrides,
    load_paths_local,
    set_path_override,
)
from certflow.config.settings import _cfg, _get_user_config, merge_user_config


def _build_nested(key: str, value: Any) -> dict:
    """把点路径键 + 值展开为嵌套字典（用于 userconfig 增量写）。

    例：``_build_nested("preferences.auto_save", True)`` -> ``{"preferences": {"auto_save": True}}``
    """
    parts = key.split(".")
    d: dict = {}
    cur = d
    for p in parts[:-1]:
        cur[p] = {}
        cur = cur[p]
    cur[parts[-1]] = value
    return d




class ConfigCenterBackend:
    """配置中心读写后端。"""

    LAYER_OVERRIDE = "override"
    LAYER_USERCONFIG = "userconfig"
    LAYER_BASE = "base"



    def read(self, key: str) -> dict[str, Any]:
        """读取某键的三层视图。

        Returns:
            ``{base, override, user, effective}``
            - base: 基础层（``config.yaml`` 经 loader，忽略所有覆盖）
            - override: ``paths.local.yaml`` 覆盖层原始值，未覆盖为 ``None``
            - user: ``userconfig`` 合并值（桶2 偏好/覆盖 + 桶3 易变状态），未配置为 ``None``
            - effective: 实际生效值 = ``user`` > ``override`` > ``base``

        关键点（修复 T10 缺陷）：偏好类键（``preferences.*`` / ``print_layout.*`` /
        ``printer_offsets.*``）的生效值来自 ``userconfig``，而非基础层；原实现只查
        ``paths.local.yaml`` + 基础层，导致这类键始终读到 ``None``，配置中心「可编辑」tab
        全部显示空白/0。此处补齐 userconfig 来源。
        """
        parts = key.split(".")
        base = _cfg(key)

        ov = load_paths_local()
        ok, override = _get_nested(ov, parts) if ov else (False, None)
        override = override if (ok and override is not None) else None

        uc = _get_user_config()
        ok_u, user = _get_nested(uc, parts)
        user = user if (ok_u and user is not None) else None

        if user is not None:
            effective = user
        elif override is not None:
            effective = override
        else:
            effective = base
        return {
            "base": base,
            "override": override,
            "user": user,
            "effective": effective,
        }




    def write(self, key: str, value: Any, layer: str) -> None:
        """按 ``layer`` 落盘写入。

        Args:
            key: 点路径键，如 ``paths.output.scans`` / ``preferences.auto_save``。
            value: 待写入值。
            layer: ``override`` / ``base``（写 paths.local.yaml）或 ``userconfig``（写 userconfig.yaml）。
        """
        if layer in (self.LAYER_OVERRIDE, self.LAYER_BASE):
            set_path_override(key, value)
        elif layer == self.LAYER_USERCONFIG:
            merge_user_config(_build_nested(key, value))
        else:
            raise ValueError(f"未知 layer: {layer!r}（应为 override/userconfig/base）")




    def list_overrides(self) -> list[str]:
        """返回覆盖层所有生效键（配置中心「我的覆盖」tab 数据源）。"""
        return list_path_overrides()