refactor: improve structure of src

src/utils/logger.ts

@@ -0,0 +1,22 @@
+// SPDX-FileCopyrightText: 2021 Johannes Loher
+//
+// SPDX-License-Identifier: MIT
+
+const loggingContext = "DS4";
+const loggingSeparator = "|";
+
+type LogLevel = "debug" | "info" | "warning" | "error";
+type LoggingFunction = (...data: unknown[]) => void;
+
+const getLoggingFunction = (type: LogLevel = "info"): LoggingFunction => {
+    const log = { debug: console.debug, info: console.info, warning: console.warn, error: console.error }[type];
+    return (...data: unknown[]) => log(loggingContext, loggingSeparator, ...data);
+};
+
+export const logger = Object.freeze({
+    debug: getLoggingFunction("debug"),
+    info: getLoggingFunction("info"),
+    warn: getLoggingFunction("warning"),
+    error: getLoggingFunction("error"),
+    getLoggingFunction,
+});

src/utils/utils.ts

@@ -0,0 +1,40 @@
+// SPDX-FileCopyrightText: 2021 Johannes Loher
+//
+// SPDX-License-Identifier: MIT
+
+/**
+ * Tests if the given `value` is truthy.
+ *
+ * If it is not truthy, an {@link Error} is thrown, which depends on the given `message` parameter:
+ * - If `message` is a string`, it is used to construct a new {@link Error} which then is thrown.
+ * - If `message` is an instance of {@link Error}, it is thrown.
+ * - If `message` is `undefined`, an {@link Error} with a default message is thrown.
+ */
+export function enforce(value: unknown, message?: string | Error): asserts value {
+    if (!value) {
+        if (!message) {
+            message =
+                getGameSafe()?.i18n.localize("DS4.ErrorUnexpectedError") ??
+                "There was an unexpected error in the Dungeonslayers 4 system. For more details, please take a look at the console (F12).";
+        }
+        throw message instanceof Error ? message : new Error(message);
+    }
+}
+
+export function getCanvas(): Canvas {
+    if (!(canvas instanceof Canvas) || !canvas.ready) {
+        throw new Error(getGame().i18n.localize("DS4.ErrorCanvasIsNotInitialized"));
+    }
+    return canvas;
+}
+
+export function getGame(): Game {
+    if (!(game instanceof Game)) {
+        throw new Error("Game is not initialized yet.");
+    }
+    return game;
+}
+
+export function getGameSafe(): Game | undefined {
+    return game instanceof Game ? game : undefined;
+}