Split modules

public/scripts/utils.js

@@ -0,0 +1,86 @@
+export {
+    onlyUnique,
+    shuffle,
+    download,
+    urlContentToDataUri,
+    getBase64Async,
+    getStringHash,
+    debounce,
+    delay,
+};
+
+/// UTILS
+function onlyUnique(value, index, array) {
+    return array.indexOf(value) === index;
+}
+
+function shuffle(array) {
+    let currentIndex = array.length,
+        randomIndex;
+
+    while (currentIndex != 0) {
+        randomIndex = Math.floor(Math.random() * currentIndex);
+        currentIndex--;
+        [array[currentIndex], array[randomIndex]] = [
+            array[randomIndex],
+            array[currentIndex],
+        ];
+    }
+    return array;
+}
+
+function download(content, fileName, contentType) {
+    const a = document.createElement("a");
+    const file = new Blob([content], { type: contentType });
+    a.href = URL.createObjectURL(file);
+    a.download = fileName;
+    a.click();
+}
+
+async function urlContentToDataUri(url, params) {
+    const response = await fetch(url, params);
+    const blob = await response.blob();
+    return await new Promise(callback => {
+        let reader = new FileReader();
+        reader.onload = function () { callback(this.result); };
+        reader.readAsDataURL(blob);
+    });
+}
+
+function getBase64Async(file) {
+    return new Promise((resolve, reject) => {
+        const reader = new FileReader();
+        reader.readAsDataURL(file);
+        reader.onload = function () {
+            resolve(reader.result);
+        };
+        reader.onerror = function (error) {
+            reject(error);
+        };
+    });
+}
+
+function getStringHash(str, seed = 0) {
+    let h1 = 0xdeadbeef ^ seed,
+        h2 = 0x41c6ce57 ^ seed;
+    for (let i = 0, ch; i < str.length; i++) {
+        ch = str.charCodeAt(i);
+        h1 = Math.imul(h1 ^ ch, 2654435761);
+        h2 = Math.imul(h2 ^ ch, 1597334677);
+    }
+
+    h1 = Math.imul(h1 ^ (h1 >>> 16), 2246822507) ^ Math.imul(h2 ^ (h2 >>> 13), 3266489909);
+    h2 = Math.imul(h2 ^ (h2 >>> 16), 2246822507) ^ Math.imul(h1 ^ (h1 >>> 13), 3266489909);
+
+    return 4294967296 * (2097151 & h2) + (h1 >>> 0);
+};
+
+function debounce(func, timeout = 300) {
+    let timer;
+    return (...args) => {
+        clearTimeout(timer);
+        timer = setTimeout(() => { func.apply(this, args); }, timeout);
+    };
+}
+
+const delay = (ms) => new Promise((res) => setTimeout(res, ms));