feat: Add an Oracle base class

gm_assistant/oracle/__init__.py

@@ -0,0 +1,4 @@
+# SPDX-FileCopyrightText: 2025 2025
+# SPDX-FileContributor: Gergely Polonkai
+#
+# SPDX-License-Identifier: GPL-3.0-or-later

gm_assistant/oracle/base.py

@@ -0,0 +1,45 @@
+# SPDX-FileCopyrightText: 2025 2025
+# SPDX-FileContributor: Gergely Polonkai
+#
+# SPDX-License-Identifier: GPL-3.0-or-later
+"""Oracle base class and related utilities"""
+
+from abc import ABCMeta, abstractmethod
+from typing import Any
+
+
+class Oracle(metaclass=ABCMeta):  # pylint: disable=too-few-public-methods
+    """Base class for Oracles"""
+
+    TYPE_MARKER: str
+
+    def __init__(self, oracle_data: dict[str, Any]) -> None:
+        self.name: str | None = None
+        self.source: str | None = None
+        self.source_url: str | None = None
+        self.parse_and_validate(oracle_data)
+
+    def parse_and_validate(self, oracle_data: dict[str, Any]) -> None:
+        """Parse and validate ``oracle_data``, essentially setting up the Oracle"""
+
+        if "type" not in oracle_data:
+            raise KeyError("type")
+
+        if "name" not in oracle_data:
+            raise KeyError("name")
+
+        if "source" not in oracle_data:
+            raise KeyError("source")
+
+        if (data_type := oracle_data["type"]) != self.TYPE_MARKER:
+            raise TypeError(f"This class can only handle {self.TYPE_MARKER} data, not {data_type}")
+
+        self.name = oracle_data["name"]
+        self.source = oracle_data["source"]
+        self.source_url = oracle_data.get("source-url")
+
+    @abstractmethod
+    def generate(self) -> str:  # pragma: no cover
+        """Make the Oracle do its work"""
+
+        raise NotImplementedError()