modeling-app/src/lib/theme.ts

export enum Themes {
  Light = 'light',
  Dark = 'dark',
  System = 'system',
}

// Get the theme from the system settings manually
export function getSystemTheme(): Exclude<Themes, 'system'> {
  return typeof globalThis.window !== 'undefined' &&
    'matchMedia' in globalThis.window
    ? window.matchMedia('(prefers-color-scheme: dark)').matches
      ? Themes.Dark
      : Themes.Light
    : Themes.Light
}

// Set the theme class on the body element
export function setThemeClass(theme: Themes) {
  if (theme === Themes.Dark) {
    document.body.classList.add('dark')
  } else {
    document.body.classList.remove('dark')
  }
}

export function getThemeColorForEngine(theme: Themes) {
  const resolvedTheme = theme === Themes.System ? getSystemTheme() : theme
  const dark = 28 / 255
  const light = 249 / 255
  return resolvedTheme === Themes.Dark
    ? { r: dark, g: dark, b: dark, a: 1 }
    : { r: light, g: light, b: light, a: 1 }
}