Function createCustomThemes

frontend/lib/src/theme/utils.ts:1492–1532

(
  themeInput: CustomThemeConfig
)

 * @returns 1 or 3 custom themes
 */
export const createCustomThemes = (
  themeInput: CustomThemeConfig
): ThemeConfig[] => {
  const hasLightConfigs = hasThemeSectionConfigs(themeInput.light)
  const hasDarkConfigs = hasThemeSectionConfigs(themeInput.dark)

  const customThemes: ThemeConfig[] = []

  // When light or dark theme section configs are set, need to create a custom theme for each
  if (hasLightConfigs || hasDarkConfigs) {
    const lightThemeInput = handleSectionInheritance(themeInput, "light")
    const lightTheme = {
      ...createTheme(CUSTOM_THEME_LIGHT_NAME, lightThemeInput),
      displayName: "Light",
    }

    const darkThemeInput = handleSectionInheritance(themeInput, "dark")
    const darkTheme = {
      ...createTheme(CUSTOM_THEME_DARK_NAME, darkThemeInput),
      displayName: "Dark",
    }

    // Also add an auto custom theme based on the system preference
    const autoCustomTheme =
      getSystemThemePreference() === "dark" ? darkTheme : lightTheme
    const autoTheme = {
      ...autoCustomTheme,
      displayName: AUTO_THEME_NAME,
      name: CUSTOM_THEME_AUTO_NAME,
    }
    // Return light, dark, and auto custom themes
    customThemes.push(lightTheme, darkTheme, autoTheme)
  } else {
    // No light/dark section configs set - single "Custom Theme" returned
    const customTheme = createTheme(CUSTOM_THEME_NAME, themeInput)
    // Return the single custom theme
    customThemes.push(customTheme)
  }

  return customThemes
}

/**
 * Set the default heading font sizes for the sidebar.