dark mode strategy

templates/element/javascript/dark_mode_bottom.php

@@ -0,0 +1,55 @@
+<?php
+
+use Cake\Core\Configure;
+
+/**
+ * @var \App\View\AppView $this
+ */
+$strategy = Configure::read('CheeseCake.darkMode.strategy', 'class');
+
+?>
+<script>
+    document.addEventListener('DOMContentLoaded', function (e) {
+        const toggleDarkLink = document.getElementById('toggle-dark-mode');
+        const toggleLightLink = document.getElementById('toggle-light-mode');
+        const toggleAutoLink = document.getElementById('toggle-auto-mode');
+        if (toggleDarkLink) {
+            toggleDarkLink.addEventListener('click', function (e) {
+                e.preventDefault();
+                localStorage.theme = 'dark';
+            <?php if ($strategy === 'class') : ?>
+                document.documentElement.classList.add('dark');
+                document.documentElement.classList.remove('auto');
+            <?php else : ?>
+                document.documentElement.dataset.theme = 'dark';
+            <?php endif; ?>
+
+            });
+        }
+        if (toggleLightLink) {
+            toggleLightLink.addEventListener('click', function (e) {
+                e.preventDefault();
+                localStorage.theme = 'light';
+            <?php if ($strategy === 'class') : ?>
+                document.documentElement.classList.remove('auto');
+                document.documentElement.classList.remove('dark');
+            <?php else : ?>
+                document.documentElement.dataset.theme = 'light';
+            <?php endif; ?>
+            });
+        }
+        if (toggleAutoLink) {
+            toggleAutoLink.addEventListener('click', function (e) {
+                e.preventDefault();
+                localStorage.theme = 'auto';
+            <?php if ($strategy === 'class') : ?>
+                document.documentElement.classList.add('auto');
+                document.documentElement.classList.remove('dark');
+
+            <?php else : ?>
+                delete document.documentElement.dataset.theme;
+            <?php endif; ?>
+            });
+        }
+    })
+</script>

templates/element/javascript/dark_mode_top.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * @var \App\View\AppView $this
+ */
+
+?>
+<script>
+    // On page load or when changing themes, best to add inline in `head` to avoid FOUC
+    document.documentElement.classList.toggle(
+        "dark",
+        localStorage.theme === "dark" ||
+        (!("theme" in localStorage) && window.matchMedia("(prefers-color-scheme: dark)").matches),
+    );
+    document.documentElement.classList.toggle(
+        "auto",
+        localStorage.theme === "auto"
+    );
+    // Whenever the user explicitly chooses light mode
+
+    // localStorage.theme = "light";
+    // // Whenever the user explicitly chooses dark mode
+    // localStorage.theme = "dark";
+    // // Whenever the user explicitly chooses to respect the OS preference
+    // localStorage.removeItem("theme");
+</script>
+