A simple studio theme provider that can be used for plugins made with Fusion

studioThemeProvider.lua

--!strict

local Plugin = script:FindFirstAncestorWhichIsA("Plugin")

local Packages = script.Parent.Parent.Packages
local Fusion = require(Packages.Fusion)
local Studio = settings().Studio

local Computed = Fusion.Computed
local Value = Fusion.Value

local currentFontFamily = Font.fromEnum(Enum.Font.Gotham).Family
local currentStudioTheme = Studio.Theme :: StudioTheme

local themeProvider = {
	Theme = Value(currentStudioTheme),
	IsDark = Value(true),
}

local function unwrap(x: Fusion.CanBeState<any>, useDependency: boolean?): any
	if typeof(x)=="table" and x.type=="State" then
		return x:get(useDependency)
	end
	return x
end

type studioStyleGuideColor = Fusion.CanBeState<Enum.StudioStyleGuideColor>
type studioStyleGuideModifier = Fusion.CanBeState<Enum.StudioStyleGuideModifier>

function themeProvider:GetColor(providedColor: studioStyleGuideColor, providedModifier: studioStyleGuideModifier?): Fusion.Computed<Color3>
	return Computed(function()
		local currentTheme = unwrap(self.Theme)
		local currentColor = unwrap(providedColor)
		local currentModifier = unwrap(providedModifier)
		return currentTheme:GetColor(currentColor, currentModifier)
	end)
end

type fontWeight = Fusion.CanBeState<Enum.FontWeight>
type fontStyle = Fusion.CanBeState<Enum.FontStyle>

function themeProvider:GetFont(providedWeight: fontWeight?, providedStyle: fontStyle?): Fusion.Computed<Font>
	return Computed(function()
		local currentFontWeight = unwrap(providedWeight) or Enum.FontWeight.Regular
		local currentFontStyle = unwrap(providedStyle) or Enum.FontStyle.Normal
		return Font.new(currentFontFamily, currentFontWeight, currentFontStyle)
	end)
end

local function updateTheme()
	currentStudioTheme = Studio.Theme :: StudioTheme
	themeProvider.Theme:set(currentStudioTheme)

	local _, _, v = currentStudioTheme:GetColor(Enum.StudioStyleGuideColor.MainBackground):ToHSV()
	themeProvider.IsDark:set(v<=0.6)
end

do --updates the theme color values when necessary
	local themeChangedConnection = Studio.ThemeChanged:Connect(updateTheme)
	updateTheme()

	Plugin.Unloading:Once(function()
		themeChangedConnection:Disconnect()
	end)
end

return themeProvider