✨ Create a ES6 Condition class for easier Condition creation

code/frontend/src/utils/Condition.js

@@ -0,0 +1,40 @@
+import isString from "is-string"
+
+
+const typeEnums = {
+    "HASHTAG": 0,
+    "TIME": 2,
+    "COORDINATES": 3,
+    "PLACE": 4,
+    "USER": 5,
+}
+
+
+/**
+ * A search/filtering Condition.
+ *
+ * See https://gitlab.steffo.eu/nest/g2-progetto/-/wikis/Specifica-delle-Conditions .
+ */
+export default class Condition {
+
+    /**
+     * Create a new Condition.
+     *
+     * @param type - The type of Condition to create.
+     *               It can be a number or one of the following strings:
+     *               `"hashtag"`, `"time"`, `"coordinates"`, `"place"`.
+     * @param content - The content of the Condition.
+     * @param id - The id of the Condition on the backend, or null if the Condition hasn't been committed yet.
+     */
+    constructor({type, content, id = null}) {
+        if(isString(type)) {
+            this.type = typeEnums[type.toUpperCase()]
+        }
+        else {
+            this.type = type
+        }
+
+        this.content = content
+        this.id = id
+    }
+}