1 files changed, 128 insertions, 0 deletions
diff --git a/tools/cru-py/cru/config.py b/tools/cru-py/cru/config.py
new file mode 100644
index 0000000..b0c83d5
--- /dev/null
+++ b/tools/cru-py/cru/config.py
@@ -0,0 +1,128 @@
+from typing import Any, TypeVar, Generic
+
+from .excp import CruInternalLogicError
+from .value import ValueType, ValueGenerator, ValidationError
+
+T = TypeVar("T")
+
+
+class ConfigItem(Generic[T]):
+    OptionalValueGenerator = ValueGenerator[T, []] | None
+
+    def __init__(self, name: str, description: str, value_type: ValueType[T], value: T | None, default_value: T, *,
+                 value_generator: OptionalValueGenerator = None) -> None:
+        self._name = name
+        self._description = description
+        self._value_type = value_type
+        self._default_value = default_value
+        self._value_generator = value_generator
+        self._value: T | None = value
+
+    @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 default_value(self) -> T:
+        return self._default_value
+
+    @property
+    def is_default(self) -> bool:
+        return self._value is None
+
+    @property
+    def is_set(self) -> bool:
+        return not self.is_default
+
+    @property
+    def value(self) -> T:
+        return self._value or self._default_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(v)
+        else:
+            self._value = self.value_type.check_value_or_try_convert_from_str(v)
+
+    @value.setter
+    def value(self, v: T) -> None:
+        self.set_value(v)
+
+    @property
+    def value_generator(self) -> OptionalValueGenerator:
+        return self._value_generator
+
+    def generate_value(self, allow_interactive=False) -> T | None:
+        if self.value_generator is None: return None
+        if self.value_generator.interactive and not allow_interactive:
+            return None
+        else:
+            v = self.generate_value()
+            try:
+                self.value_type.check_value(v)
+                return v
+            except ValidationError as e:
+                raise CruInternalLogicError("Config value generator returns invalid value.", name=self.name, inner=e)
+
+    def copy(self) -> "ConfigItem":
+        return ConfigItem(self.name, self.description, self.value_type,
+                          self._value.copy() if self._value is not None else None, self._default_value.copy(),
+                          value_generator=self.value_generator)
+
+
+class Configuration:
+    def __init__(self, items: None | list[ConfigItem] = None) -> None:
+        self._items: list[ConfigItem] = items or []
+
+    @property
+    def items(self) -> list[ConfigItem]:
+        return self._items
+
+    @property
+    def item_map(self) -> dict[str, ConfigItem]:
+        return {i.name: i for i in self.items}
+
+    def get_optional_item(self, name: str) -> ConfigItem | None:
+        for i in self.items:
+            if i.name == name:
+                return i
+        return None
+
+    def clear(self) -> None:
+        self._items.clear()
+
+    def has_item(self, name: str) -> bool:
+        return self.get_optional_item(name) is not None
+
+    def add_item(self, item: ConfigItem):
+        i = self.get_optional_item(item.name)
+        if i is not None:
+            raise CruInternalLogicError("Config item of the name already exists.", name=item.name)
+        self.items.append(item)
+        return item
+
+    def set_value(self, name: str, v: Any, /, allow_convert_from_str=False):
+        i = self.get_optional_item(name)
+        if i is None:
+            raise CruInternalLogicError("No config item of the name. Can't set value.", name=name)
+        i.set_value(v, allow_convert_from_str)
+
+    def copy(self) -> "Configuration":
+        return Configuration([i.copy() for i in self.items])
+
+    def __getitem__(self, name: str) -> ConfigItem:
+        i = self.get_optional_item(name)
+        if i is not None:
+            return i
+        raise CruInternalLogicError('No config item of the name.', name=name)
+
+    def __contains__(self, name: str):
+        return self.has_item(name)