From 355405daa3296f20ebb5161002650a59fc195d9c Mon Sep 17 00:00:00 2001
From: Joachim <joachim.robert@protonmail.com>
Date: Fri, 17 Dec 2021 20:40:58 +0100
Subject: [PATCH] Front-end: Fix Safari details display and enhance dropdown on
 mobile

---
 bookwyrm/static/css/bookwyrm.css            |  68 +++++++++++--
 bookwyrm/static/js/bookwyrm.js              | 100 ++++++++++++++++++++
 bookwyrm/templates/components/dropdown.html |   2 +-
 3 files changed, 159 insertions(+), 11 deletions(-)

diff --git a/bookwyrm/static/css/bookwyrm.css b/bookwyrm/static/css/bookwyrm.css
index f385e629..45d976e3 100644
--- a/bookwyrm/static/css/bookwyrm.css
+++ b/bookwyrm/static/css/bookwyrm.css
@@ -93,6 +93,10 @@ body {
     display: inline !important;
 }
 
+
+/** File input styles
+ ******************************************************************************/
+
 input[type=file]::file-selector-button {
     -moz-appearance: none;
     -webkit-appearance: none;
@@ -119,17 +123,12 @@ input[type=file]::file-selector-button:hover {
     color: #363636;
 }
 
-details .dropdown-menu {
-    display: block !important;
-}
 
-details.dropdown[open] summary.dropdown-trigger::before {
-    content: "";
-    position: fixed;
-    top: 0;
-    bottom: 0;
-    left: 0;
-    right: 0;
+/** General `details` element styles
+ ******************************************************************************/
+
+summary::-webkit-details-marker {
+    display: none;
 }
 
 summary::marker {
@@ -147,6 +146,55 @@ summary::marker {
     margin-top: 1em;
 }
 
+/** Details dropdown
+ ******************************************************************************/
+
+details.dropdown[open] summary.dropdown-trigger::before {
+    content: "";
+    position: fixed;
+    top: 0;
+    bottom: 0;
+    left: 0;
+    right: 0;
+}
+
+details .dropdown-menu {
+    display: block !important;
+}
+
+details .dropdown-menu button {
+    /* Fix weird Safari defaults */
+    box-sizing: border-box;
+}
+
+details.dropdown .dropdown-menu button:focus-visible,
+details.dropdown .dropdown-menu a:focus-visible {
+    outline-style: auto;
+    outline-offset: -2px;
+}
+
+@media only screen and (max-width: 768px) {
+    details.dropdown[open] summary.dropdown-trigger::before {
+        background-color:  rgba(0, 0, 0, 0.5);
+        z-index: 30;
+    }
+    details .dropdown-menu {
+        position: fixed;
+        top: 0;
+        left: 0;
+        width: 100%;
+        height: 100%;
+        display: flex !important;
+        align-items: center;
+        justify-content: center;
+        pointer-events: none;
+        z-index: 100;
+    }
+    details .dropdown-menu > * {
+        pointer-events: all;
+    }
+}
+
 /** Shelving
  ******************************************************************************/
 
diff --git a/bookwyrm/static/js/bookwyrm.js b/bookwyrm/static/js/bookwyrm.js
index 2b78bf51..3e0b1ad8 100644
--- a/bookwyrm/static/js/bookwyrm.js
+++ b/bookwyrm/static/js/bookwyrm.js
@@ -51,6 +51,12 @@ let BookWyrm = new class {
                     'click',
                     this.duplicateInput.bind(this)
             
+            ))
+        document.querySelectorAll('details.dropdown')
+                .forEach(node => node.addEventListener(
+                    'toggle',
+                    this.handleDetailsDropdown.bind(this)
+            
             ))
     }
 
@@ -482,4 +488,98 @@ let BookWyrm = new class {
 
         textareaEl.parentNode.appendChild(copyButtonEl)
     }
+
+    /**
+     * Handle the details dropdown component.
+     *
+     * @param  {Event} event - Event fired by a `details` element
+     *                         with the `dropdown` class name, on toggle.
+     * @return {undefined}
+     */
+    handleDetailsDropdown(event) {
+        const detailsElement = event.target;
+        const summaryElement = detailsElement.querySelector('summary');
+        const menuElement = detailsElement.querySelector('.dropdown-menu');
+        const htmlElement = document.querySelector('html');
+
+        if (detailsElement.open) {
+            // Focus first menu element
+            menuElement.querySelectorAll(
+                'a[href]:not([disabled]), button:not([disabled])'
+            )[0].focus();
+            // Enable focus trap
+            menuElement.addEventListener('keydown', this.handleFocusTrap);
+            // Close on Esc
+            detailsElement.addEventListener('keydown', handleEscKey);
+
+            // Clip page if Mobile
+            if (this.isMobile()) {
+                htmlElement.classList.add('is-clipped');
+            }
+        } else {
+            summaryElement.focus();
+            // Disable focus trap
+            menuElement.removeEventListener('keydown', this.handleFocusTrap);
+
+            // Unclip page
+            if (this.isMobile()) {
+                htmlElement.classList.remove('is-clipped');
+            }
+        }
+
+        function handleEscKey(event) {
+            if (event.key !== 'Escape') { 
+                return; 
+            }
+
+            summaryElement.click();
+        }
+    }
+
+    /**
+     * Check if windows matches mobile media query.
+     *
+     * @return {Boolean}
+     */
+    isMobile() {
+        return window.matchMedia("(max-width: 768px)").matches;
+    }
+
+    /**
+     * Focus trap handler
+     *
+     * @param  {Event} event - Keydown event.
+     * @return {undefined}
+     */
+    handleFocusTrap(event) {
+        if (event.key !== 'Tab') { 
+            return; 
+        }
+
+        const focusableEls = event.currentTarget.querySelectorAll(
+            [
+                'a[href]:not([disabled])',
+                'button:not([disabled])',
+                'textarea:not([disabled])',
+                'input:not([type="hidden"]):not([disabled])',
+                'select:not([disabled])',
+                'details:not([disabled])',
+                '[tabindex]:not([tabindex="-1"]):not([disabled])'
+            ].join(',')
+        );
+        const firstFocusableEl = focusableEls[0];  
+        const lastFocusableEl = focusableEls[focusableEls.length - 1];
+
+        if (event.shiftKey ) /* Shift + tab */ {
+            if (document.activeElement === firstFocusableEl) {
+                lastFocusableEl.focus();
+                event.preventDefault();
+            }
+        } else /* Tab */ {
+            if (document.activeElement === lastFocusableEl) {
+                firstFocusableEl.focus();
+                event.preventDefault();
+            }
+        }
+    }
 }();
diff --git a/bookwyrm/templates/components/dropdown.html b/bookwyrm/templates/components/dropdown.html
index b3710271..0e07bf99 100644
--- a/bookwyrm/templates/components/dropdown.html
+++ b/bookwyrm/templates/components/dropdown.html
@@ -15,7 +15,7 @@
         {% block dropdown-trigger %}{% endblock %}
     </summary>
 
-    <div class="dropdown-menu control">
+    <div class="dropdown-menu">
         <ul
             id="menu_options_{{ uuid }}"
             class="dropdown-content p-0 is-clipped"