Cleanup Lua plugin implementation.

* Move the UI code out of the plugin logic.
* Add types where needed.
* Move into game package.
* Improve error handling.
* Simplify settings behavior.
* Don't load disabled plugins.
* Remove knowledge of non-base plugins from game generation.

Fixes https://github.com/Khopa/dcs_liberation/issues/311

game/plugins/luaplugin.py

@@ -0,0 +1,180 @@
+from __future__ import annotations
+
+import json
+import logging
+import textwrap
+from dataclasses import dataclass
+from pathlib import Path
+from typing import List, Optional, TYPE_CHECKING
+
+from game.settings import Settings
+
+if TYPE_CHECKING:
+    from game.operation.operation import Operation
+
+
+class LuaPluginWorkOrder:
+
+    def __init__(self, parent_mnemonic: str, filename: str, mnemonic: str,
+                 disable: bool) -> None:
+        self.parent_mnemonic = parent_mnemonic
+        self.filename = filename
+        self.mnemonic = mnemonic
+        self.disable = disable
+
+    def work(self, operation: Operation) -> None:
+        if self.disable:
+            operation.bypass_plugin_script(self.mnemonic)
+        else:
+            operation.inject_plugin_script(self.parent_mnemonic, self.filename,
+                                           self.mnemonic)
+
+
+class PluginSettings:
+    def __init__(self, identifier: str, enabled_by_default: bool) -> None:
+        self.identifier = identifier
+        self.enabled_by_default = enabled_by_default
+        self.settings = Settings()
+        self.initialize_settings()
+
+    def set_settings(self, settings: Settings):
+        self.settings = settings
+        self.initialize_settings()
+
+    def initialize_settings(self) -> None:
+        # Plugin options are saved in the game's Settings, but it's possible for
+        # plugins to change across loads. If new plugins are added or new
+        # options added to those plugins, initialize the new settings.
+        self.settings.initialize_plugin_option(self.identifier,
+                                               self.enabled_by_default)
+
+    @property
+    def enabled(self) -> bool:
+        return self.settings.plugin_option(self.identifier)
+
+    def set_enabled(self, enabled: bool) -> None:
+        self.settings.set_plugin_option(self.identifier, enabled)
+
+
+class LuaPluginOption(PluginSettings):
+    def __init__(self, identifier: str, name: str,
+                 enabled_by_default: bool) -> None:
+        super().__init__(identifier, enabled_by_default)
+        self.name = name
+
+
+@dataclass(frozen=True)
+class LuaPluginDefinition:
+    identifier: str
+    name: str
+    present_in_ui: bool
+    enabled_by_default: bool
+    options: List[LuaPluginOption]
+    work_orders: List[LuaPluginWorkOrder]
+    config_work_orders: List[LuaPluginWorkOrder]
+
+    @classmethod
+    def from_json(cls, name: str, path: Path) -> LuaPluginDefinition:
+        data = json.loads(path.read_text())
+
+        options = []
+        for option in data.get("specificOptions"):
+            option_id = option["mnemonic"]
+            options.append(LuaPluginOption(
+                identifier=f"{name}.{option_id}",
+                name=option.get("nameInUI", name),
+                enabled_by_default=option.get("defaultValue")
+            ))
+
+        work_orders = []
+        for work_order in data.get("scriptsWorkOrders"):
+            work_orders.append(LuaPluginWorkOrder(
+                name, work_order.get("file"), work_order["mnemonic"],
+                work_order.get("disable", False)
+            ))
+        config_work_orders = []
+        for work_order in data.get("configurationWorkOrders"):
+            config_work_orders.append(LuaPluginWorkOrder(
+                name, work_order.get("file"), work_order["mnemonic"],
+                work_order.get("disable", False)
+            ))
+
+        return cls(
+            identifier=name,
+            name=data["nameInUI"],
+            present_in_ui=not data.get("skipUI", False),
+            enabled_by_default=data.get("defaultValue", False),
+            options=options,
+            work_orders=work_orders,
+            config_work_orders=config_work_orders
+        )
+
+
+class LuaPlugin(PluginSettings):
+
+    def __init__(self, definition: LuaPluginDefinition) -> None:
+        self.definition = definition
+        super().__init__(self.definition.identifier,
+                         self.definition.enabled_by_default)
+
+    @property
+    def name(self) -> str:
+        return self.definition.name
+
+    @property
+    def show_in_ui(self) -> bool:
+        return self.definition.present_in_ui
+
+    @property
+    def options(self) -> List[LuaPluginOption]:
+        return self.definition.options
+
+    @classmethod
+    def from_json(cls, name: str, path: Path) -> Optional[LuaPlugin]:
+        try:
+            definition = LuaPluginDefinition.from_json(name, path)
+        except KeyError:
+            logging.exception("Required plugin configuration value missing")
+            return None
+
+        return cls(definition)
+
+    def set_settings(self, settings: Settings):
+        super().set_settings(settings)
+        for option in self.definition.options:
+            option.set_settings(self.settings)
+
+    def inject_scripts(self, operation: Operation) -> None:
+        for work_order in self.definition.work_orders:
+            work_order.work(operation)
+
+    def inject_configuration(self, operation: Operation) -> None:
+        # inject the plugin options
+        if self.options:
+            option_decls = []
+            for option in self.options:
+                enabled = str(option.enabled).lower()
+                name = option.identifier
+                option_decls.append(
+                    f"    dcsLiberation.plugins.{name} = {enabled}")
+
+            joined_options = "\n".join(option_decls)
+
+            lua = textwrap.dedent(f"""\
+                -- {self.identifier} plugin configuration.
+
+                if dcsLiberation then
+                    if not dcsLiberation.plugins then
+                        dcsLiberation.plugins = {{}}
+                    end
+                    dcsLiberation.plugins.{self.identifier} = {{}}
+                    {joined_options}
+                end
+
+            """)
+
+            operation.inject_lua_trigger(
+                lua, f"{self.identifier} plugin configuration")
+
+        for work_order in self.definition.config_work_orders:
+            work_order.work(operation)