Files
greyhaven-design-system/components/theme-provider.tsx
2026-04-13 15:33:00 -05:00

88 lines
2.2 KiB
TypeScript

'use client'
import * as React from 'react'
type Theme = 'light' | 'dark' | 'system'
interface ThemeProviderProps {
children: React.ReactNode
defaultTheme?: Theme
storageKey?: string
attribute?: string
}
interface ThemeContextValue {
theme: Theme
resolvedTheme: 'light' | 'dark'
setTheme: (theme: Theme) => void
}
const ThemeContext = React.createContext<ThemeContextValue | undefined>(undefined)
function getSystemTheme(): 'light' | 'dark' {
if (typeof window === 'undefined') return 'light'
return window.matchMedia('(prefers-color-scheme: dark)').matches
? 'dark'
: 'light'
}
export function ThemeProvider({
children,
defaultTheme = 'system',
storageKey = 'greyhaven-theme',
attribute = 'class',
}: ThemeProviderProps) {
const [theme, setThemeState] = React.useState<Theme>(() => {
if (typeof window === 'undefined') return defaultTheme
return (localStorage.getItem(storageKey) as Theme) || defaultTheme
})
const resolvedTheme = theme === 'system' ? getSystemTheme() : theme
const setTheme = React.useCallback(
(newTheme: Theme) => {
setThemeState(newTheme)
if (typeof window !== 'undefined') {
localStorage.setItem(storageKey, newTheme)
}
},
[storageKey],
)
React.useEffect(() => {
const root = document.documentElement
if (attribute === 'class') {
root.classList.remove('light', 'dark')
root.classList.add(resolvedTheme)
} else {
root.setAttribute(attribute, resolvedTheme)
}
}, [resolvedTheme, attribute])
// Listen for system theme changes when theme is 'system'
React.useEffect(() => {
if (theme !== 'system') return
const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)')
const handler = () => setThemeState((prev) => (prev === 'system' ? 'system' : prev))
mediaQuery.addEventListener('change', handler)
return () => mediaQuery.removeEventListener('change', handler)
}, [theme])
return (
<ThemeContext.Provider value={{ theme, resolvedTheme, setTheme }}>
{children}
</ThemeContext.Provider>
)
}
export function useTheme() {
const context = React.useContext(ThemeContext)
if (!context) {
throw new Error('useTheme must be used within a ThemeProvider')
}
return context
}