1 files changed, 196 insertions, 0 deletions
diff --git a/python/cru/config.py b/python/cru/config.py
new file mode 100644
index 0000000..0f6f0d0
--- /dev/null
+++ b/python/cru/config.py
@@ -0,0 +1,196 @@
+from __future__ import annotations
+
+from typing import Any, TypeVar, Generic
+
+from ._error import CruException
+from .list import CruUniqueKeyList
+from .value import (
+    INTEGER_VALUE_TYPE,
+    TEXT_VALUE_TYPE,
+    CruValueTypeError,
+    ValueGeneratorBase,
+    ValueType,
+)
+
+_T = TypeVar("_T")
+
+
+class CruConfigError(CruException):
+    def __init__(self, message: str, item: ConfigItem, *args, **kwargs):
+        super().__init__(message, *args, **kwargs)
+        self._item = item
+
+    @property
+    def item(self) -> ConfigItem:
+        return self._item
+
+
+class ConfigItem(Generic[_T]):
+    def __init__(
+        self,
+        name: str,
+        description: str,
+        value_type: ValueType[_T],
+        value: _T | None = None,
+        /,
+        default: ValueGeneratorBase[_T] | _T | None = None,
+    ) -> None:
+        self._name = name
+        self._description = description
+        self._value_type = value_type
+        self._value = value
+        self._default = default
+
+    @property
+    def name(self) -> str:
+        return self._name
+
+    @property
+    def description(self) -> str:
+        return self._description
+
+    @property
+    def value_type(self) -> ValueType[_T]:
+        return self._value_type
+
+    @property
+    def is_set(self) -> bool:
+        return self._value is not None
+
+    @property
+    def value(self) -> _T:
+        if self._value is None:
+            raise CruConfigError(
+                "Config value is not set.",
+                self,
+                user_message=f"Config item {self.name} is not set.",
+            )
+        return self._value
+
+    @property
+    def value_str(self) -> str:
+        return self.value_type.convert_value_to_str(self.value)
+
+    def set_value(self, v: _T | str, allow_convert_from_str=False):
+        if allow_convert_from_str:
+            self._value = self.value_type.check_value_or_try_convert_from_str(v)
+        else:
+            self._value = self.value_type.check_value(v)
+
+    def reset(self):
+        self._value = None
+
+    @property
+    def default(self) -> ValueGeneratorBase[_T] | _T | None:
+        return self._default
+
+    @property
+    def can_generate_default(self) -> bool:
+        return self.default is not None
+
+    def generate_default_value(self) -> _T:
+        if self.default is None:
+            raise CruConfigError(
+                "Config item does not support default value generation.", self
+            )
+        elif isinstance(self.default, ValueGeneratorBase):
+            v = self.default.generate()
+        else:
+            v = self.default
+        try:
+            self.value_type.check_value(v)
+            return v
+        except CruValueTypeError as e:
+            raise CruConfigError(
+                "Config value generator returns an invalid value.", self
+            ) from e
+
+    def copy(self) -> "ConfigItem":
+        return ConfigItem(
+            self.name,
+            self.description,
+            self.value_type,
+            self.value,
+            self.default,
+        )
+
+    @property
+    def description_str(self) -> str:
+        return f"{self.name} ({self.value_type.name}): {self.description}"
+
+
+class Configuration(CruUniqueKeyList[ConfigItem[Any], str]):
+    def __init__(self):
+        super().__init__(lambda c: c.name)
+
+    def get_set_items(self) -> list[ConfigItem[Any]]:
+        return [item for item in self if item.is_set]
+
+    def get_unset_items(self) -> list[ConfigItem[Any]]:
+        return [item for item in self if not item.is_set]
+
+    @property
+    def all_set(self) -> bool:
+        return len(self.get_unset_items()) == 0
+
+    @property
+    def all_not_set(self) -> bool:
+        return len(self.get_set_items()) == 0
+
+    def add_text_config(
+        self,
+        name: str,
+        description: str,
+        value: str | None = None,
+        default: ValueGeneratorBase[str] | str | None = None,
+    ) -> ConfigItem[str]:
+        item = ConfigItem(name, description, TEXT_VALUE_TYPE, value, default)
+        self.add(item)
+        return item
+
+    def add_int_config(
+        self,
+        name: str,
+        description: str,
+        value: int | None = None,
+        default: ValueGeneratorBase[int] | int | None = None,
+    ) -> ConfigItem[int]:
+        item = ConfigItem(name, description, INTEGER_VALUE_TYPE, value, default)
+        self.add(item)
+        return item
+
+    def set_config_item(
+        self,
+        name: str,
+        value: Any | str,
+        allow_convert_from_str=True,
+    ) -> None:
+        item = self.get(name)
+        item.set_value(
+            value,
+            allow_convert_from_str=allow_convert_from_str,
+        )
+
+    def reset_all(self) -> None:
+        for item in self:
+            item.reset()
+
+    def to_dict(self) -> dict[str, Any]:
+        return {item.name: item.value for item in self}
+
+    def to_str_dict(self) -> dict[str, str]:
+        return {
+            item.name: item.value_type.convert_value_to_str(item.value) for item in self
+        }
+
+    def set_value_dict(
+        self,
+        value_dict: dict[str, Any],
+        allow_convert_from_str: bool = False,
+    ) -> None:
+        for name, value in value_dict.items():
+            item = self.get(name)
+            item.set_value(
+                value,
+                allow_convert_from_str=allow_convert_from_str,
+            )