Add Wikipedia page box

Logic/UIEventSource.ts

@@ -61,10 +61,30 @@ export class UIEventSource<T> {
         run();
         return source;
     }
-    
+
+    /**
+     * Converts a promise into a UIVentsource, sets the UIEVentSource when the result is calculated.
+     * If the promise fails, the value will stay undefined
+     * @param promise
+     * @constructor
+     */
     public static FromPromise<T>(promise : Promise<T>): UIEventSource<T>{
         const src = new UIEventSource<T>(undefined)
         promise?.then(d => src.setData(d))
+        promise?.catch(err => console.warn("Promise failed:", err))
+        return src
+    }
+
+    /**
+     * Converts a promise into a UIVentsource, sets the UIEVentSource when the result is calculated.
+     * If the promise fails, the value will stay undefined
+     * @param promise
+     * @constructor
+     */
+    public static FromPromiseWithErr<T>(promise : Promise<T>): UIEventSource<{success: T} | {error: any}>{
+        const src = new UIEventSource<{success: T}|{error: any}>(undefined)
+        promise?.then(d => src.setData({success:d}))
+        promise?.catch(err => src.setData({error: err}))
         return src
     }
 

Logic/Web/Wikipedia.ts

@@ -0,0 +1,49 @@
+/**
+ * Some usefull utility functions around the wikipedia API
+ */
+import {Utils} from "../../Utils";
+import WikipediaBox from "../../UI/WikipediaBox";
+
+export default class Wikipedia {
+
+    /**
+     * When getting a wikipedia page data result, some elements (e.g. navigation, infoboxes, ...) should be removed if 'removeInfoBoxes' is set.
+     * We do this based on the classes. This set contains a blacklist of the classes to remove
+     * @private
+     */
+    private static readonly classesToRemove = [
+        "shortdescription",
+        "sidebar",
+        "infobox",
+        "mw-editsection",
+        "hatnote" // Often redirects
+    ]
+
+    public static async GetArticle(options: {
+        pageName: string,
+        language?: "en" | string,
+        section?: number,
+    }): Promise<string> {
+
+        let section = ""
+        if (options.section !== undefined) {
+            section = "&section=" + options.section
+        }
+        const url = `https://${options.language ?? "en"}.wikipedia.org/w/api.php?action=parse${section}&format=json&origin=*&prop=text&page=` + options.pageName
+        const response = await Utils.downloadJson(url)
+        const html = response["parse"]["text"]["*"];
+
+        const div = document.createElement("div")
+        div.innerHTML = html
+        const content = Array.from(div.children)[0]
+
+        for (const forbiddenClass of Wikipedia.classesToRemove) {
+           const toRemove = content.getElementsByClassName(forbiddenClass)
+            for (const toRemoveElement of Array.from(toRemove)) {
+                toRemoveElement.parentElement?.removeChild(toRemoveElement)
+            }
+        }
+        return content.innerHTML;
+    }
+
+}