feat(ui): Dark Mode (#2493)

src_assets/common/assets/web/theme.js

@@ -0,0 +1,84 @@
+const getStoredTheme = () => localStorage.getItem('theme')
+const setStoredTheme = theme => localStorage.setItem('theme', theme)
+
+export const getPreferredTheme = () => {
+    const storedTheme = getStoredTheme()
+    if (storedTheme) {
+        return storedTheme
+    }
+
+    return window.matchMedia('(prefers-color-scheme: dark)').matches ? 'dark' : 'light'
+}
+
+const setTheme = theme => {
+    if (theme === 'auto') {
+        document.documentElement.setAttribute(
+            'data-bs-theme',
+            (window.matchMedia('(prefers-color-scheme: dark)').matches ? 'dark' : 'light')
+        )
+    } else {
+        document.documentElement.setAttribute('data-bs-theme', theme)
+    }
+}
+
+export const showActiveTheme = (theme, focus = false) => {
+    const themeSwitcher = document.querySelector('#bd-theme')
+
+    if (!themeSwitcher) {
+        return
+    }
+
+    const themeSwitcherText = document.querySelector('#bd-theme-text')
+    const activeThemeIcon = document.querySelector('.theme-icon-active i')
+    const btnToActive = document.querySelector(`[data-bs-theme-value="${theme}"]`)
+    const classListOfActiveBtn = btnToActive.querySelector('i').classList
+
+    document.querySelectorAll('[data-bs-theme-value]').forEach(element => {
+        element.classList.remove('active')
+        element.setAttribute('aria-pressed', 'false')
+    })
+
+    btnToActive.classList.add('active')
+    btnToActive.setAttribute('aria-pressed', 'true')
+    activeThemeIcon.classList.remove(...activeThemeIcon.classList.values())
+    activeThemeIcon.classList.add(...classListOfActiveBtn)
+    const themeSwitcherLabel = `${themeSwitcherText.textContent} (${btnToActive.textContent.trim()})`
+    themeSwitcher.setAttribute('aria-label', themeSwitcherLabel)
+
+    if (focus) {
+        themeSwitcher.focus()
+    }
+}
+
+export function setupThemeToggleListener() {
+    document.querySelectorAll('[data-bs-theme-value]')
+        .forEach(toggle => {
+            toggle.addEventListener('click', () => {
+                const theme = toggle.getAttribute('data-bs-theme-value')
+                setStoredTheme(theme)
+                setTheme(theme)
+                showActiveTheme(theme, true)
+            })
+        })
+
+    showActiveTheme(getPreferredTheme(), false)
+}
+
+export function loadAutoTheme() {
+    (() => {
+        'use strict'
+
+        setTheme(getPreferredTheme())
+
+        window.matchMedia('(prefers-color-scheme: dark)').addEventListener('change', () => {
+            const storedTheme = getStoredTheme()
+            if (storedTheme !== 'light' && storedTheme !== 'dark') {
+                setTheme(getPreferredTheme())
+            }
+        })
+
+        window.addEventListener('DOMContentLoaded', () => {
+            showActiveTheme(getPreferredTheme())
+        })
+    })()
+}