feat(id): produce UUID with generateId. move to /utils/Identifier.js

This is the replace the much simpler but prone to problem simple (and small) random Integer generation.
And moved the function to its own `/utils/Identifier.js` file for ease of maintenance.

Close gwenaelp#14

src/DiagramModel.js

@@ -1,8 +1,5 @@
 import DiagramNode from "./DiagramNode";
-
-var generateId = function() {
-  return Math.trunc(Math.random() * 1000);
-};
+import { generateId } from "./utils/Identifier";
 
 /**
  * @class DiagramModel

src/DiagramNode.js

@@ -1,6 +1,4 @@
-var generateId = function() {
-  return Math.trunc(Math.random() * 1000);
-};
+import { generateId } from "./utils/Identifier";
 
 /**
  * @class DiagramNode

src/components/Diagram.vue

@@ -97,9 +97,7 @@ import DiagramNode from "./DiagramNode";
 import DiagramLink from "./DiagramLink";
 import DiagramPort from "./DiagramPort";
 
-var generateId = function() {
-  return Math.trunc(Math.random() * 1000);
-};
+import { generateId } from "./../utils/Identifier";
 
 function getAbsoluteXY(element) {
   var viewportElement = document.documentElement;
@@ -253,12 +251,10 @@ export default {
 
           links[this.draggedItem.linkIndex].points[
             this.draggedItem.pointIndex
-          ].x =
-            coords.x;
+          ].x = coords.x;
           links[this.draggedItem.linkIndex].points[
             this.draggedItem.pointIndex
-          ].y =
-            coords.y;
+          ].y = coords.y;
           this.updateLinksPositions();
         } else {
           let coords = this.convertXYtoViewPort(this.mouseX, this.mouseY);

src/utils/Identifier.js

@@ -0,0 +1,15 @@
+/**
+ * Generate a UUID (v1)
+ * @param {Integer} c clock-seq-and-reserved clock-seq-low
+ * @return {String} The UUID
+ * http://www.rfcreader.com/#rfc4122_line385 allows random instead of MAC address
+ * https://www.famkruithof.net/uuid/uuidgen
+ * https://realityripple.com/Tools/UnUUID/
+ */
+export function generateId(c = 9999) {
+  const t = ((Date.now() + 12219292800000) * 1e4).toString(16);
+  const n = crypto.getRandomValues(new Uint8Array(6)).reduce((sum, x, i) => {
+    return sum + (i === 0 ? x | 1 : x).toString(16).padStart(2, "0");
+  }, "");
+  return `${t.slice(-8)}-${t.slice(-12, -8)}-1${t.slice(0, 3)}-${c}-${n}`;
+}