re-name static directory, move stylesheet to its own folder

javascript/util.js

@@ -0,0 +1,50 @@
+export const utility =
+{
+    generateID() {
+        let code = "";
+        let charPool = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
+        for (let i = 0; i < 10; i++) {
+            code += charPool[this.getRandomInt(61)]
+        }
+        return code;
+    },
+
+    getRandomInt(max) {
+        return Math.floor(Math.random() * Math.floor(max));
+    },
+
+    shuffle(array) {
+        for (let i = array.length - 1; i > 0; i--) {
+            const j = Math.floor(Math.random() * (i + 1));
+            [array[i], array[j]] = [array[j], array[i]];
+        }
+        return array;
+    },
+
+    validateCustomRolesJsonObject(name, expectedKeys) {
+        let value = localStorage.getItem(name);
+        if (value !== null) {
+            let valueJson;
+            try {
+                valueJson = JSON.parse(value);
+            } catch(e) {
+                console.error(e.message);
+                localStorage.removeItem(name);
+                return false;
+            }
+            if (valueJson && Array.isArray(valueJson)) { // some defensive programming - check if it's an array, and that the object has the expected structure
+                for (let i = 0; i < valueJson.length; i++){
+                    if (expectedKeys.some((key) => !Object.keys(valueJson[i]).includes(key))) {
+                        console.error("tried to read invalid object: " + valueJson[i] + " with expected keys: " + expectedKeys);
+                        valueJson.splice(i, 1);
+                        localStorage.setItem(name, JSON.stringify(valueJson));
+                    }
+                }
+                return valueJson;
+            } else { // object has been messed with. remove it.
+                localStorage.removeItem(name);
+                return false;
+            }
+        }
+    }
+};