rearrage_stuff

scenes/scene.js

@@ -0,0 +1,128 @@
+import { sprintf } from "sprintf-js";
+import { Session } from "../models/session.js";
+import { Prompt } from "./prompt.js";
+
+/**
+ * Scene - a class for showing one or more prompts in a row.
+ *
+ * Scenes are mostly there to keep track of which prompt to show,
+ * and to store data for subsequent prompts to access.
+ *
+ * The prompts themselves are responsible for data validation and
+ * interpretation.
+ *
+ * @abstract
+ */
+export class Scene {
+    /**
+     * @type {string|string[]} This text is shown when the scene begins
+     */
+    introText = "";
+
+    /** @readonly @constant @type {Session} */
+    _session;
+    get session() {
+        return this._session;
+    }
+
+    /**
+     * The Prompt that is currently active.
+     * I.e. the handler for the latest question we asked.
+     *
+     * @readonly
+     * @type {Prompt}
+     */
+    _prompt;
+    get prompt() {
+        return this._prompt;
+    }
+
+    constructor() {}
+
+    /** @param {Session} session */
+    execute(session) {
+        this._session = session;
+        if (this.introText) {
+            this.session.sendText(this.introText);
+        }
+        this.onReady();
+    }
+
+    /** @abstract */
+    onReady() {
+        throw new Error("Abstract method must be implemented by subclass");
+    }
+
+    /**
+     * @param {Prompt} prompt
+     */
+    showPrompt(prompt) {
+        this._prompt = prompt;
+        prompt.execute();
+    }
+
+    /** @param {new (scene: Scene) => Prompt} promptClassReference */
+    show(promptClassReference) {
+        this.showPrompt(new promptClassReference(this));
+    }
+
+    /**
+     * Triggered when a user types a :command that begins with a colon
+     * and the current Prompt cannot handle that command.
+     *
+     * @param {string} command
+     * @param {any[]} args
+     */
+    onColon(command, args) {
+        const propertyName = "onColon__" + command;
+        const property = this[propertyName];
+
+        //
+        // Default: we have no handler for the Foo command
+        if (property === undefined) {
+            this.session.sendError(`You cannot ${command.toUpperCase()} right now`); // :foo ==> you cannot FOO right now
+            return;
+        }
+
+        //
+        // If the prompt has a method called onColon_foo() =>
+        if (typeof property === "function") {
+            property.call(this, args);
+            return;
+        }
+
+        //
+        // If the prompt has a _string_ called onColon_foo =>
+        if (typeof property === "string") {
+            this.session.sendText(property);
+            return;
+        }
+
+        //
+        // We found a property that has the right name but the wrong type.
+        throw new Error(
+            [
+                `Logic error. Scene has a handler for a command called ${command}`,
+                `but it is neither a function or a string, but a ${typeof property}`,
+            ].join(" "),
+        );
+    }
+
+    //
+    // Easter ægg
+    // Example dynamic colon handler
+    /** @param {any[]} args */
+    onColon__imperial(args) {
+        if (args.length === 0) {
+            this.session.sendText("The imperial system is the freeest system ever. Also the least good");
+        }
+
+        const n = Number(args[0]);
+
+        this.session.sendText(
+            sprintf("%.2f centimeters is only %.2f inches. This is american wands are so short!", n, n / 2.54),
+        );
+    }
+
+    onColon__hi = "Hoe";
+}