From 3d259c07186c2751a3adf3ed4f8e71a83436a77a Mon Sep 17 00:00:00 2001
From: Gilles Devillard <gillesde@ie.ibm.com>
Date: Fri, 16 Jul 2021 15:00:45 +0100
Subject: [PATCH] Overwrite Switcher component

---
 .../components/Switcher/Switcher.js           | 141 ++++++++++++++++++
 1 file changed, 141 insertions(+)
 create mode 100644 src/gatsby-theme-carbon/components/Switcher/Switcher.js

diff --git a/src/gatsby-theme-carbon/components/Switcher/Switcher.js b/src/gatsby-theme-carbon/components/Switcher/Switcher.js
new file mode 100644
index 0000000..2756ced
--- /dev/null
+++ b/src/gatsby-theme-carbon/components/Switcher/Switcher.js
@@ -0,0 +1,141 @@
+import React, {
+  useContext,
+  useRef,
+  useLayoutEffect,
+  useEffect,
+  useState,
+} from 'react';
+import cx from 'classnames';
+import useMedia from 'use-media';
+import { Locked16 } from '@carbon/icons-react';
+import NavContext from 'gatsby-theme-carbon/src/util/context/NavContext';
+import { nav, open, divider, link, linkDisabled } from 'gatsby-theme-carbon/src/components/Switcher/Switcher.module.scss';
+
+const Switcher = ({ children }) => {
+  const lgBreakpoint = useMedia('min-width: 1056px');
+  const { switcherIsOpen, toggleNavState } = useContext(NavContext);
+  const listRef = useRef(null);
+  const [height, setHeight] = useState(0);
+
+  useEffect(() => {
+    const collapseOpenNavs = function (e) {
+      if (e.which === 27) {
+        toggleNavState('switcherIsOpen', 'close');
+      }
+    };
+
+    document.addEventListener('keyup', collapseOpenNavs);
+
+    return function cleanup() {
+      document.removeEventListener('keyup', collapseOpenNavs);
+    };
+  }, [toggleNavState]);
+
+  // calculate and update height
+  useLayoutEffect(() => {
+    if (switcherIsOpen) {
+      setHeight(listRef.current.offsetHeight + 40);
+    } else {
+      setHeight(0);
+    }
+  }, [listRef, switcherIsOpen]);
+
+  const maxHeight = !lgBreakpoint && switcherIsOpen ? '100%' : `${height}px`;
+
+  return (
+    <nav
+      className={cx(nav, { [open]: switcherIsOpen })}
+      aria-label="IBM Design ecosystem"
+      tabIndex="-1"
+      style={{ maxHeight }}>
+      <ul ref={listRef}>{children}</ul>
+    </nav>
+  );
+};
+
+export const SwitcherDivider = (props) => (
+  <li className={divider}>
+    <span {...props} />
+  </li>
+);
+
+export const SwitcherLink = ({
+  disabled,
+  children,
+  isInternal,
+  href: hrefProp,
+  ...rest
+}) => {
+  const href = disabled || !hrefProp ? undefined : hrefProp;
+  const className = disabled ? linkDisabled : link;
+  const { switcherIsOpen } = useContext(NavContext);
+  const openTabIndex = disabled ? '-1' : 0;
+
+  return (
+    <li>
+      <a
+        aria-disabled={disabled}
+        role="button"
+        tabIndex={switcherIsOpen ? openTabIndex : '-1'}
+        className={className}
+        href={href}
+        {...rest}>
+        {children}
+        {isInternal && <Locked16 />}
+      </a>
+    </li>
+  );
+};
+
+// https://css-tricks.com/using-css-transitions-auto-dimensions/
+// Note: if you change this, update the max-height in the switcher stylesheet
+const DefaultChildren = () => (
+  <>
+    <SwitcherDivider>Foundations</SwitcherDivider>
+    <SwitcherLink href="https://ibm.com/brand" isInternal>
+      IBM Brand Center
+    </SwitcherLink>
+    <SwitcherLink href="https://ibm.com/design/language">
+      IBM Design Language
+    </SwitcherLink>
+    <SwitcherDivider>Implementation</SwitcherDivider>
+    <SwitcherLink href="https://www.carbondesignsystem.com/">
+      Carbon Design System
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/standards/web/carbon-for-ibm-dotcom/">
+      Carbon for IBM.com
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/design/event/">
+      IBM Event Design
+    </SwitcherLink>
+    <SwitcherDivider>Practices</SwitcherDivider>
+    <SwitcherLink href="https://www.ibm.com/design/thinking/">
+      Enterprise Design Thinking
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/able/">
+      IBM Accessibility
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/design/ai">
+      IBM Design for AI
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/design/research/">
+      IBM Design Research
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/services/ibmix/">
+      IBM iX
+    </SwitcherLink>
+    <SwitcherDivider>Community</SwitcherDivider>
+    <SwitcherLink href="https://www.ibm.com/design/">
+      IBM Design
+    </SwitcherLink>
+    <SwitcherLink href="https://www.ibm.com/design/racial-equity-in-design">
+      Racial Equity in Design
+    </SwitcherLink>
+  </>
+);
+
+Switcher.defaultProps = {
+  children: <DefaultChildren />,
+};
+
+export default Switcher;