From 50257463b7aac0c301c930e964cbcd88e637957d Mon Sep 17 00:00:00 2001
From: robonen <robonenandrew@gmail.com>
Date: Wed, 20 Nov 2024 16:49:24 +0700
Subject: [PATCH] feat(packages/platform): add focusGuard brwoser util

---
 .../src/browsers/focusGuard/index.test.ts     | 69 +++++++++++++++++++
 .../platform/src/browsers/focusGuard/index.ts | 50 ++++++++++++++
 packages/platform/src/browsers/index.ts       |  1 +
 3 files changed, 120 insertions(+)
 create mode 100644 packages/platform/src/browsers/focusGuard/index.test.ts
 create mode 100644 packages/platform/src/browsers/focusGuard/index.ts
 create mode 100644 packages/platform/src/browsers/index.ts

diff --git a/packages/platform/src/browsers/focusGuard/index.test.ts b/packages/platform/src/browsers/focusGuard/index.test.ts
new file mode 100644
index 0000000..22e29a9
--- /dev/null
+++ b/packages/platform/src/browsers/focusGuard/index.test.ts
@@ -0,0 +1,69 @@
+import { describe, it, expect, beforeEach } from 'vitest';
+import { focusGuard, createGuardAttrs } from '.';
+
+describe('focusGuard', () => {
+  beforeEach(() => {
+    document.body.innerHTML = '';
+  });
+
+  it('initialize with the correct default namespace', () => {
+    const guard = focusGuard();
+    
+    expect(guard.selector).toBe('data-focus-guard');
+  });
+
+  it('create focus guards in the DOM', () => {
+    const guard = focusGuard();
+    guard.createGuard();
+
+    const guards = document.querySelectorAll(`[${guard.selector}]`);
+    expect(guards.length).toBe(2);
+
+    guards.forEach((element) => {
+      expect(element.tagName).toBe('SPAN');
+      expect(element.getAttribute('tabindex')).toBe('0');
+    });
+  });
+
+  it('remove focus guards from the DOM correctly', () => {
+    const guard = focusGuard();
+    guard.createGuard();
+    guard.removeGuard();
+
+    const guards = document.querySelectorAll(`[${guard.selector}]`);
+    
+    expect(guards.length).toBe(0);
+  });
+
+  it('reuse the same guards when calling createGuard multiple times', () => {
+    const guard = focusGuard();
+    guard.createGuard();
+    guard.createGuard();
+
+    guard.removeGuard();
+    const guards = document.querySelectorAll(`[${guard.selector}]`);
+
+    expect(guards.length).toBe(0);
+  });
+
+  it('allow custom namespaces', () => {
+    const namespace = 'custom-guard';
+    const guard = focusGuard(namespace);
+    guard.createGuard();
+
+    expect(guard.selector).toBe(`data-${namespace}`);
+
+    const guards = document.querySelectorAll(`[${guard.selector}]`);
+    expect(guards.length).toBe(2);
+  });
+
+  it('createGuardAttrs should create a valid guard element', () => {
+    const namespace = 'custom-guard';
+    const element = createGuardAttrs(namespace);
+
+    expect(element.tagName).toBe('SPAN');
+    expect(element.getAttribute(namespace)).toBe('');
+    expect(element.getAttribute('tabindex')).toBe('0');
+    expect(element.getAttribute('style')).toBe('outline: none; opacity: 0; pointer-events: none; position: fixed;');
+  });
+});
\ No newline at end of file
diff --git a/packages/platform/src/browsers/focusGuard/index.ts b/packages/platform/src/browsers/focusGuard/index.ts
new file mode 100644
index 0000000..f4d7ec0
--- /dev/null
+++ b/packages/platform/src/browsers/focusGuard/index.ts
@@ -0,0 +1,50 @@
+/**
+ * @name focusGuard
+ * @category Browsers
+ * @description Adds a pair of focus guards at the boundaries of the DOM tree to ensure consistent focus behavior
+ * 
+ * @param {string} namespace - The namespace to use for the guard attributes
+ * @returns {Object} - An object containing the selector, createGuard, and removeGuard functions
+ * 
+ * @example
+ * const guard = focusGuard();
+ * guard.createGuard();
+ * guard.removeGuard();
+ * 
+ * @example
+ * const guard = focusGuard('focus-guard');
+ * guard.createGuard();
+ * guard.removeGuard();
+ * 
+ * @since 0.0.3
+ */
+export function focusGuard(namespace: string = 'focus-guard') {
+  const guardAttr = `data-${namespace}`;
+
+  const createGuard = () => {
+    const edges = document.querySelectorAll(`[${guardAttr}]`);
+
+    document.body.insertAdjacentElement('afterbegin', edges[0] ?? createGuardAttrs(guardAttr));
+    document.body.insertAdjacentElement('beforeend', edges[1] ?? createGuardAttrs(guardAttr));
+  };
+
+  const removeGuard = () => {
+    document.querySelectorAll(`[${guardAttr}]`).forEach((element) => element.remove());
+  };
+
+  return {
+    selector: guardAttr,
+    createGuard,
+    removeGuard,
+  };
+}
+
+export function createGuardAttrs(namespace: string) {
+  const element = document.createElement('span');
+
+  element.setAttribute(namespace, '');
+  element.setAttribute('tabindex', '0');
+  element.setAttribute('style', 'outline: none; opacity: 0; pointer-events: none; position: fixed;');
+
+  return element;
+}
\ No newline at end of file
diff --git a/packages/platform/src/browsers/index.ts b/packages/platform/src/browsers/index.ts
new file mode 100644
index 0000000..0569ecb
--- /dev/null
+++ b/packages/platform/src/browsers/index.ts
@@ -0,0 +1 @@
+export * from './focusGuard';
\ No newline at end of file