Add layered configuration resolver

README.md

@@ -13,6 +13,7 @@
 
 ## Table of Contents
 
+- [What's new (2026-06-21) — Layered Configuration Resolver](#whats-new-2026-06-21--layered-configuration-resolver)
 - [What's new (2026-06-21) — Server-Sent Events (SSE) Client Parser](#whats-new-2026-06-21--server-sent-events-sse-client-parser)
 - [What's new (2026-06-21) — Dotenv (.env) Parsing](#whats-new-2026-06-21--dotenv-env-parsing)
 - [What's new (2026-06-21) — RFC 9457 Problem Details Parsing](#whats-new-2026-06-21--rfc-9457-problem-details-parsing)
@@ -133,6 +134,12 @@
 
 ---
 
+## What's new (2026-06-21) — Layered Configuration Resolver
+
+Compose config with `defaults < file < env < CLI` precedence. Full reference: [`docs/source/Eng/doc/new_features/v81_features_doc.rst`](docs/source/Eng/doc/new_features/v81_features_doc.rst).
+
+- **`LayeredConfig` / `deep_merge` / `SourceTrace`** (`AC_resolve_config`, `AC_explain_config`): `json_patch.merge_patch` merges two docs, `config_sync` is last-write-wins, `AssetStore` is flat-per-env — none compose an ordered precedence stack with deep merge or report which layer won each key. `add_layer(name, mapping, priority)` then `resolve()` deep-merges (nested dicts recursively, scalars/lists replaced); `explain("db.host")` names the winning layer. Layers are caller-supplied (env passed in, never `os.environ` implicitly). Pure-stdlib, deterministic.
+
 ## What's new (2026-06-21) — Server-Sent Events (SSE) Client Parser
 
 Consume `text/event-stream` responses. Full reference: [`docs/source/Eng/doc/new_features/v80_features_doc.rst`](docs/source/Eng/doc/new_features/v80_features_doc.rst).

README/README_zh-CN.md

@@ -12,6 +12,7 @@
 
 ## 目录
 
+- [本次更新 (2026-06-21) — 分层配置解析器](#本次更新-2026-06-21--分层配置解析器)
 - [本次更新 (2026-06-21) — Server-Sent Events (SSE) 客户端解析器](#本次更新-2026-06-21--server-sent-events-sse-客户端解析器)
 - [本次更新 (2026-06-21) — Dotenv (.env) 解析](#本次更新-2026-06-21--dotenv-env-解析)
 - [本次更新 (2026-06-21) — RFC 9457 Problem Details 解析](#本次更新-2026-06-21--rfc-9457-problem-details-解析)
@@ -132,6 +133,12 @@
 
 ---
 
+## 本次更新 (2026-06-21) — 分层配置解析器
+
+以 `defaults < file < env < CLI` 优先级组合配置。完整参考:[`docs/source/Zh/doc/new_features/v81_features_doc.rst`](../docs/source/Zh/doc/new_features/v81_features_doc.rst)。
+
+- **`LayeredConfig` / `deep_merge` / `SourceTrace`**(`AC_resolve_config`、`AC_explain_config`):`json_patch.merge_patch` 只合并两份文档,`config_sync` 是 last-write-wins,`AssetStore` 是每环境扁平 —— 都无法组成有序优先级堆叠并深度合并,也无法报告每个键由哪层胜出。`add_layer(name, mapping, priority)` 后 `resolve()` 深度合并(嵌套 dict 递归、标量/list 替换);`explain("db.host")` 标明胜出层。各层由调用端提供(env 由外部传入,绝不隐含 `os.environ`)。纯标准库、确定。
+
 ## 本次更新 (2026-06-21) — Server-Sent Events (SSE) 客户端解析器
 
 消费 `text/event-stream` 响应。完整参考:[`docs/source/Zh/doc/new_features/v80_features_doc.rst`](../docs/source/Zh/doc/new_features/v80_features_doc.rst)。

README/README_zh-TW.md

@@ -12,6 +12,7 @@
 
 ## 目錄
 
+- [本次更新 (2026-06-21) — 分層設定解析器](#本次更新-2026-06-21--分層設定解析器)
 - [本次更新 (2026-06-21) — Server-Sent Events (SSE) 用戶端解析器](#本次更新-2026-06-21--server-sent-events-sse-用戶端解析器)
 - [本次更新 (2026-06-21) — Dotenv (.env) 解析](#本次更新-2026-06-21--dotenv-env-解析)
 - [本次更新 (2026-06-21) — RFC 9457 Problem Details 解析](#本次更新-2026-06-21--rfc-9457-problem-details-解析)
@@ -132,6 +133,12 @@
 
 ---
 
+## 本次更新 (2026-06-21) — 分層設定解析器
+
+以 `defaults < file < env < CLI` 優先序組合設定。完整參考:[`docs/source/Zh/doc/new_features/v81_features_doc.rst`](../docs/source/Zh/doc/new_features/v81_features_doc.rst)。
+
+- **`LayeredConfig` / `deep_merge` / `SourceTrace`**(`AC_resolve_config`、`AC_explain_config`):`json_patch.merge_patch` 只合併兩份文件,`config_sync` 是 last-write-wins,`AssetStore` 是每環境扁平 —— 都無法組成有序優先序堆疊並深度合併,也無法回報每個鍵由哪層勝出。`add_layer(name, mapping, priority)` 後 `resolve()` 深度合併(巢狀 dict 遞迴、純量/list 取代);`explain("db.host")` 標明勝出層。各層由呼叫端提供(env 由外部傳入,絕不隱含 `os.environ`)。純標準函式庫、具決定性。
+
 ## 本次更新 (2026-06-21) — Server-Sent Events (SSE) 用戶端解析器
 
 消費 `text/event-stream` 回應。完整參考:[`docs/source/Zh/doc/new_features/v80_features_doc.rst`](../docs/source/Zh/doc/new_features/v80_features_doc.rst)。

docs/source/Eng/doc/new_features/v81_features_doc.rst

@@ -0,0 +1,45 @@
+Layered Configuration Resolver
+==============================
+
+``json_patch.merge_patch`` merges exactly two documents, ``config_sync``
+resolves by last-write-wins timestamp, and ``AssetStore`` is flat per
+environment. None of them compose an ordered ``defaults < file < env < CLI``
+precedence stack with a deep dict merge, nor report *which layer won each key*.
+This adds that 12-factor resolver.
+
+Pure standard library (``copy``); imports no ``PySide6``. Layers are plain
+mappings supplied by the caller (the env layer is passed in, never read from
+``os.environ`` implicitly), so resolution is deterministic in CI.
+
+Headless API
+------------
+
+.. code-block:: python
+
+    from je_auto_control import LayeredConfig, deep_merge
+
+    cfg = (LayeredConfig()
+           .add_layer("defaults", {"db": {"host": "local", "port": 5432}})
+           .add_layer("file", file_values, priority=10)
+           .add_layer("env", env_values, priority=20))
+
+    settings = cfg.resolve()                  # {"db": {"host": ..., "port": ...}}
+    host = cfg.get("db.host")
+    trace = cfg.explain("db.host")            # SourceTrace(value=..., layer="env")
+
+``add_layer`` registers a named layer; higher ``priority`` wins (priority
+defaults to insertion order, so later layers override earlier ones).
+``resolve`` deep-merges every layer in ascending priority — nested dicts are
+merged recursively while scalars and lists are replaced. ``get`` reads a dotted
+key from the resolved config with a default; ``explain`` returns a
+``SourceTrace`` naming the winning layer for a dotted key (raising ``KeyError``
+when absent). ``deep_merge`` is exposed as a standalone two-mapping helper.
+
+Executor commands
+-----------------
+
+``AC_resolve_config`` deep-merges a ``layers`` list (each ``{name, mapping,
+priority?}``) into ``{config}``. ``AC_explain_config`` returns ``{trace}`` (the
+value and winning layer) for a dotted ``key``. Both are exposed as MCP tools
+(``ac_resolve_config`` / ``ac_explain_config``) and as Script Builder commands
+under **Data**.

docs/source/Eng/eng_index.rst

@@ -103,6 +103,7 @@ Comprehensive guides for all AutoControl features.
    doc/new_features/v78_features_doc
    doc/new_features/v79_features_doc
    doc/new_features/v80_features_doc
+   doc/new_features/v81_features_doc
    doc/ocr_backends/ocr_backends_doc
    doc/observability/observability_doc
    doc/operations_layer/operations_layer_doc

docs/source/Zh/doc/new_features/v81_features_doc.rst

@@ -0,0 +1,37 @@
+分層設定解析器
+============
+
+``json_patch.merge_patch`` 只合併兩份文件,``config_sync`` 以 last-write-wins 時間戳解析,
+``AssetStore`` 則是每環境的扁平結構。它們都無法組成一個有序的 ``defaults < file < env < CLI`` 優先序
+堆疊並做深度 dict 合併,也無法回報*每個鍵由哪一層勝出*。本功能補上這個 12-factor 解析器。
+
+純標準函式庫(``copy``);不匯入 ``PySide6``。各層為呼叫端提供的純 mapping(env 層由外部傳入,絕不
+隱含讀取 ``os.environ``),因此解析在 CI 中具決定性。
+
+無頭 API
+--------
+
+.. code-block:: python
+
+    from je_auto_control import LayeredConfig, deep_merge
+
+    cfg = (LayeredConfig()
+           .add_layer("defaults", {"db": {"host": "local", "port": 5432}})
+           .add_layer("file", file_values, priority=10)
+           .add_layer("env", env_values, priority=20))
+
+    settings = cfg.resolve()                  # {"db": {"host": ..., "port": ...}}
+    host = cfg.get("db.host")
+    trace = cfg.explain("db.host")            # SourceTrace(value=..., layer="env")
+
+``add_layer`` 註冊一個具名層;``priority`` 越高越勝出(預設為插入順序,因此後加的層覆蓋先前的)。
+``resolve`` 依優先序由低到高深度合併每一層 —— 巢狀 dict 遞迴合併,而純量與 list 直接取代。``get`` 以
+點分鍵從解析後設定讀取並帶預設值;``explain`` 回傳 ``SourceTrace``,標明點分鍵的勝出層(不存在時拋
+``KeyError``)。``deep_merge`` 另以獨立的雙 mapping 輔助函式提供。
+
+執行器命令
+----------
+
+``AC_resolve_config`` 把 ``layers`` 清單(每筆 ``{name, mapping, priority?}``)深度合併成
+``{config}``。``AC_explain_config`` 對點分 ``key`` 回傳 ``{trace}``(值與勝出層)。兩者皆以 MCP 工具
+(``ac_resolve_config`` / ``ac_explain_config``)以及 Script Builder 中 **Data** 分類下的命令提供。

docs/source/Zh/zh_index.rst

@@ -103,6 +103,7 @@ AutoControl 所有功能的完整使用指南。
    doc/new_features/v78_features_doc
    doc/new_features/v79_features_doc
    doc/new_features/v80_features_doc
+   doc/new_features/v81_features_doc
    doc/ocr_backends/ocr_backends_doc
    doc/observability/observability_doc
    doc/operations_layer/operations_layer_doc

je_auto_control/__init__.py

@@ -274,6 +274,10 @@
 from je_auto_control.utils.dotenv import (
     dotenv_values, dump_dotenv, load_dotenv, parse_dotenv,
 )
+# Layered config resolver (defaults < file < env < CLI, with provenance)
+from je_auto_control.utils.layered_config import (
+    LayeredConfig, SourceTrace, deep_merge,
+)
 # Outbound CloudEvents emitter
 from je_auto_control.utils.events import (
     EventEmitter, post_cloudevent, to_cloudevent,
@@ -860,6 +864,7 @@ def start_autocontrol_gui(*args, **kwargs):
     "rank_automation_candidates",
     "Asset", "AssetStore", "AssetValue", "active_environment",
     "dotenv_values", "dump_dotenv", "load_dotenv", "parse_dotenv",
+    "LayeredConfig", "SourceTrace", "deep_merge",
     "EventEmitter", "post_cloudevent", "to_cloudevent",
     "WebhookChannel", "WebhookResult", "notify_webhook", "set_default_poster",
     "json_extract", "json_query", "json_query_one",

je_auto_control/gui/script_builder/command_schema.py

@@ -1678,6 +1678,25 @@ def _add_resilience_specs(specs: List[CommandSpec]) -> None:
         ),
         description="Parse a text/event-stream blob into events.",
     ))
+    specs.append(CommandSpec(
+        "AC_resolve_config", "Data", "Layered Config: Resolve",
+        fields=(
+            FieldSpec("layers", FieldType.STRING,
+                      placeholder='[{"name": "defaults", "mapping": {}}, '
+                                  '{"name": "env", "mapping": {}, '
+                                  '"priority": 10}]'),
+        ),
+        description="Deep-merge ordered config layers into one config.",
+    ))
+    specs.append(CommandSpec(
+        "AC_explain_config", "Data", "Layered Config: Explain Key",
+        fields=(
+            FieldSpec("layers", FieldType.STRING,
+                      placeholder='[{"name": "defaults", "mapping": {}}]'),
+            FieldSpec("key", FieldType.STRING, placeholder="db.host"),
+        ),
+        description="Show the value and winning layer for a dotted config key.",
+    ))
     specs.append(CommandSpec(
         "AC_rate_limit", "Flow", "Rate Limit (Token Bucket)",
         fields=(

je_auto_control/utils/executor/action_executor.py

@@ -3050,6 +3050,31 @@ def _parse_sse(text: str) -> Dict[str, Any]:
     return {"events": [event.to_dict() for event in parse_event_stream(text)]}
 
 
+def _build_layered_config(layers: Any):
+    """Build a LayeredConfig from a list of {name, mapping, priority?} dicts."""
+    import json
+    from je_auto_control.utils.layered_config import LayeredConfig
+    if isinstance(layers, str):
+        layers = json.loads(layers)
+    config = LayeredConfig()
+    for layer in layers:
+        config.add_layer(layer["name"], layer.get("mapping", {}),
+                         layer.get("priority"))
+    return config
+
+
+def _resolve_config(layers: Any) -> Dict[str, Any]:
+    """Adapter: deep-merge config layers into a resolved {config}."""
+    return {"config": _build_layered_config(layers).resolve()}
+
+
+def _explain_config(layers: Any, key: str) -> Dict[str, Any]:
+    """Adapter: report the value and winning layer for a dotted config key."""
+    trace = _build_layered_config(layers).explain(key)
+    return {"trace": {"key": trace.key, "value": trace.value,
+                      "layer": trace.layer}}
+
+
 def _percentiles(samples: Any, qs: Any = None) -> Dict[str, Any]:
     """Adapter: exact percentiles of a numeric sample list (or JSON string)."""
     import json
@@ -4134,6 +4159,8 @@ def __init__(self):
             "AC_parse_dotenv": _parse_dotenv,
             "AC_load_dotenv": _load_dotenv,
             "AC_parse_sse": _parse_sse,
+            "AC_resolve_config": _resolve_config,
+            "AC_explain_config": _explain_config,
             "AC_unified_diff": _unified_diff,
             "AC_apply_unified": _apply_unified,
             "AC_three_way_merge": _three_way_merge,

je_auto_control/utils/layered_config/__init__.py

@@ -0,0 +1,6 @@
+"""Layered configuration resolution for AutoControl."""
+from je_auto_control.utils.layered_config.layered_config import (
+    LayeredConfig, SourceTrace, deep_merge,
+)
+
+__all__ = ["LayeredConfig", "SourceTrace", "deep_merge"]

je_auto_control/utils/layered_config/layered_config.py

@@ -0,0 +1,104 @@
+"""Ordered, deep-merging configuration resolver with per-key provenance.
+
+``json_patch.merge_patch`` merges exactly two documents and ``config_sync``
+resolves by last-write-wins timestamp; ``AssetStore`` is flat-per-environment.
+None of them compose an ordered ``defaults < file < env < CLI`` precedence
+stack with a deep dict merge, nor report *which layer won each key*. This adds
+that 12-factor resolver.
+
+Pure standard library (``copy``); imports no ``PySide6``. Layers are plain
+mappings supplied by the caller (the env layer is passed in, never read from
+``os.environ`` implicitly), so resolution is deterministic in CI.
+"""
+import copy
+from dataclasses import dataclass
+from typing import Any, Dict, List, Mapping, Optional, Tuple
+
+
+@dataclass(frozen=True)
+class SourceTrace:
+    """Where a resolved key's value came from."""
+
+    key: str
+    value: Any
+    layer: Optional[str]
+
+
+@dataclass
+class _Layer:
+    name: str
+    mapping: Dict[str, Any]
+    priority: int
+    index: int
+
+
+def deep_merge(base: Mapping[str, Any],
+               override: Mapping[str, Any]) -> Dict[str, Any]:
+    """Recursively merge ``override`` onto ``base``; ``override`` wins leaves."""
+    result: Dict[str, Any] = dict(base)
+    for key, value in override.items():
+        current = result.get(key)
+        if isinstance(value, Mapping) and isinstance(current, Mapping):
+            result[key] = deep_merge(current, value)
+        else:
+            result[key] = copy.deepcopy(value)
+    return result
+
+
+def _get_path(mapping: Mapping[str, Any],
+              parts: List[str]) -> Tuple[bool, Any]:
+    current: Any = mapping
+    for part in parts:
+        if not isinstance(current, Mapping) or part not in current:
+            return False, None
+        current = current[part]
+    return True, current
+
+
+class LayeredConfig:
+    """Compose configuration layers by priority with deep merging."""
+
+    def __init__(self) -> None:
+        self._layers: List[_Layer] = []
+
+    def add_layer(self, name: str, mapping: Mapping[str, Any],
+                  priority: Optional[int] = None) -> "LayeredConfig":
+        """Add a layer; higher ``priority`` wins (default: insertion order)."""
+        index = len(self._layers)
+        resolved_priority = index if priority is None else priority
+        self._layers.append(
+            _Layer(name, dict(mapping or {}), resolved_priority, index))
+        return self
+
+    def layer_names(self) -> List[str]:
+        """The layer names in insertion order."""
+        return [layer.name for layer in self._layers]
+
+    def _ascending(self) -> List[_Layer]:
+        return sorted(self._layers, key=lambda layer: (layer.priority,
+                                                       layer.index))
+
+    def resolve(self) -> Dict[str, Any]:
+        """Deep-merge all layers in ascending priority into one config dict."""
+        merged: Dict[str, Any] = {}
+        for layer in self._ascending():
+            merged = deep_merge(merged, layer.mapping)
+        return merged
+
+    def get(self, dotted_key: str, default: Any = None) -> Any:
+        """Return the resolved value for a dotted key, or ``default``."""
+        found, value = _get_path(self.resolve(), dotted_key.split("."))
+        return value if found else default
+
+    def explain(self, dotted_key: str) -> SourceTrace:
+        """Return the value and the winning layer name for a dotted key."""
+        parts = dotted_key.split(".")
+        found, value = _get_path(self.resolve(), parts)
+        if not found:
+            raise KeyError(dotted_key)
+        for layer in sorted(self._layers, reverse=True,
+                            key=lambda item: (item.priority, item.index)):
+            layer_found, _ = _get_path(layer.mapping, parts)
+            if layer_found:
+                return SourceTrace(dotted_key, value, layer.name)
+        return SourceTrace(dotted_key, value, None)