local Selection = game:GetService("Selection")
local HttpService = game:GetService("HttpService")
local StarterPlayer = game:GetService("StarterPlayer")
local StudioService = game:GetService("StudioService")
local TextChatService = game:GetService("TextChatService")

local classes = {}
local outStream = ""
local stackLevel = 0

local singletons = {
	Speaker = Instance.new("Sound"), -- close enough
	Terrain = workspace:WaitForChild("Terrain", 1000),
	ParabolaAdornment = Instance.new("BoxHandleAdornment"), -- close enough
	StarterPlayerScripts = StarterPlayer:WaitForChild("StarterPlayerScripts"),
	StarterCharacterScripts = StarterPlayer:WaitForChild("StarterCharacterScripts"),
	ChatWindowConfiguration = TextChatService:WaitForChild("ChatWindowConfiguration", 10),
	ChatInputBarConfiguration = TextChatService:WaitForChild("ChatInputBarConfiguration", 10),
}

local exceptionClasses = {
	PackageLink = true,
	ScriptDebugger = true,
	ChatWindowConfiguration = true,
	ChatInputBarConfiguration = true,
}

local numberTypes = {
	int = true,
	long = true,
	int64 = true,
	float = true,
	double = true,
}

local stringTypes = {
	string = true,
	Content = true,
	BinaryString = true,
	ProtectedString = true,
}

local isCoreScript = pcall(function()
	local restricted = game:GetService("RobloxPluginGuiService")
	return tostring(restricted)
end)

local function write(formatString, ...)
	local tabs = string.rep(" ", stackLevel * 4)
	local fmt = formatString or ""

	local value = tabs .. fmt:format(...)
	outStream = outStream .. value
end

local function writeLine(formatString, ...)
	if not formatString then
		outStream = outStream .. "\n"
		return
	end

	write(formatString .. "\n", ...)
end

local function openStack()
	writeLine("{")
	stackLevel += 1
end

local function closeStack()
	stackLevel -= 1
	writeLine("}")
end

local function clearStream()
	stackLevel = 0
	outStream = ""
end

local function exportStream(label)
	local results = outStream:gsub("\n\n\n", "\n\n")
	local export

	if plugin then
		export = Instance.new("Script")
		export.Archivable = false
		export.Source = results
		export.Name = label
		export.Parent = workspace

		Selection:Add({ export })
	end

	if isCoreScript then
		StudioService:CopyToClipboard(results)
	elseif not plugin then
		warn(label)
		print(results)
	else
		wait()
		plugin:OpenScript(export)
	end
end

local function getTags(object)
	local tags = {}

	if object.Tags ~= nil then
		for _, tag in pairs(object.Tags) do
			tags[tag] = true
		end
	end

	if object.Name == "Terrain" then
		tags.NotCreatable = nil
	end

	return tags
end

local function upcastInheritance(class, root)
	local superClass = classes[class.Superclass]

	if not superClass then
		return
	end

	if not root then
		root = class
	end

	if not superClass.Inherited then
		superClass.Inherited = root
	end

	upcastInheritance(superClass, root)
end

local function canCreateClass(class)
	local tags = getTags(class)
	local canCreate = true

	if tags.NotCreatable then
		canCreate = false
	end

	if tags.Service then
		canCreate = true
	end

	if tags.Settings then
		canCreate = false
	end

	if singletons[class.Name] then
		canCreate = true
	end

	return canCreate
end

local function collectProperties(class)
	local propMap = {}

	for _, member in ipairs(class.Members) do
		if member.MemberType == "Property" then
			local propName = member.Name
			propMap[propName] = member
		end
	end

	return propMap
end

local function createProperty(propName, propType)
	local category = "DataType"
	local name = propType

	if propType:find(":") then
		local data = string.split(propType, ":")
		category = data[1]
		name = data[2]
	end

	return
{
		Name = propName,

		Serialization = {
			CanSave = true,
			CanLoad = true,
		},

		ValueType = {
			Category = category,
			Name = name,
		},

		Security = "None",
	}
end

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-- Formatting
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------

local formatting: Format = require(script.Formatting)
type FormatFunc = formatting.FormatFunc
type Format = formatting.Format

local formatLinks = {
	["int"] = "Int",
	["long"] = "Int",

	["float"] = "Float",
	["byte[]"] = "Bytes",
	["double"] = "Double",
	["boolean"] = "Bool",

	["string"] = "String",
	["Content"] = "String",

	["Color3uint8"] = "Color3",
	["ProtectedString"] = "String",
}

local function getFormatFunction(valueType: string): FormatFunc
	if not formatting[valueType] then
		valueType = formatLinks[valueType]
	end

	return formatting[valueType] or formatting.Null
end

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-- Property Patches
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------

local patches = require(script.PropertyPatches)
local patchIndex = {}

function patchIndex:__index(key)
	if not rawget(self, key) then
		rawset(self, key, {})
	end

	return self[key]
end

local function getPatches(className)
	local classPatches = patches[className]
	return setmetatable(classPatches, patchIndex)
end

setmetatable(patches, patchIndex)

---------------------------------------------------------------------------------------------------------------------------------------------------------------------------
-- Main
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------

local baseUrl = "https://raw.githubusercontent.com/MaximumADHD/Roblox-Client-Tracker/roblox/"
local toolbar, button

if plugin then
	toolbar = plugin:CreateToolbar("C# API Dump")

	button = toolbar:CreateButton(
		"Dump API",
		"Generates a C# dump of Roblox's Class/Enum API.",
		"rbxasset://textures/Icon_Stream_Off@2x.png"
	)

	button.ClickableWhenViewportHidden = true
end

local function getAsync(url)
	local enabled

	if isCoreScript then
		enabled = HttpService:GetHttpEnabled()
		HttpService:SetHttpEnabled(true)
	end

	local result = HttpService:GetAsync(url)

	if isCoreScript then
		HttpService:SetHttpEnabled(enabled)
	end

	return result
end

local function generateClasses()
	local env = getfenv()
	local version = getAsync(baseUrl .. "version.txt")

	local apiDump = getAsync(baseUrl .. "API-Dump.json")
	apiDump = HttpService:JSONDecode(apiDump)

	local classNames = {}
	classes = {}

	local enumMap = {
		Axis = true,
		FontSize = true,
		FontStyle = true,
		FontWeight = true,
	}

	for _, class in ipairs(apiDump.Classes) do
		local className = class.Name
		local superClass = classes[class.Superclass]

		if singletons[className] then
			class.Singleton = true
			class.Object = singletons[className]
		end

		if superClass and canCreateClass(class) then
			local classTags = getTags(class)

			if classTags.Service then
				pcall(function()
					if not className:find("Network") then
						class.Object = game:GetService(className)
					end
				end)
			elseif not classTags.NotCreatable then
				pcall(function()
					local dumpFolder = game:FindFirstChild("DumpFolder")
					class.Object = Instance.new(className)

					if dumpFolder then
						local old = dumpFolder:FindFirstChildOfClass(className)

						if old then
							old:Destroy()
						end

						class.Object.Name = className
						class.Object.Parent = dumpFolder
					end
				end)
			end

			upcastInheritance(class)
		end

		classes[className] = class
		table.insert(classNames, className)
	end

	outStream = ""

	writeLine("// Auto-generated list of creatable Roblox classes.")
	writeLine("// Updated as of %s", version)
	writeLine()

	writeLine("using System;")
	writeLine()

	writeLine("using RobloxFiles.DataTypes;")
	writeLine("using RobloxFiles.Enums;")
	writeLine("using RobloxFiles.Utility;")
	writeLine()

	writeLine("#pragma warning disable IDE1006 // Naming Styles")
	writeLine()

	writeLine("namespace RobloxFiles")
	openStack()

	for i, className in ipairs(classNames) do
		local class = classes[className]
		local classTags = getTags(class)

		local registerClass = canCreateClass(class)
		local object = class.Object

		if class.Inherited then
			registerClass = true
		end

		if class.Name == "Instance" or class.Name == "Studio" then
			registerClass = false
		end

		local noSecurityCheck = pcall(function()
			if not classTags.Service then
				return tostring(object)
			end
		end)

		if not noSecurityCheck then
			object = nil
		end

		if not object then
			if class.Inherited then
				object = class.Inherited.Object
			elseif singletons[className] then
				object = singletons[className]
			else
				registerClass = false
			end
		end

		if exceptionClasses[class.Name] then
			registerClass = true
		end

		if registerClass then
			local objectType

			if classTags.NotCreatable and class.Inherited and not class.Singleton then
				objectType = "abstract class"
			else
				objectType = "class"
			end

			writeLine("public %s %s : %s", objectType, className, class.Superclass)
			openStack()

			local classPatches = getPatches(className)
			local redirectProps = classPatches.Redirect

			local propMap = collectProperties(class)
			local propNames = {}

			for _, propName in pairs(classPatches.Remove) do
				propMap[propName] = nil
			end

			for propName in pairs(propMap) do
				table.insert(propNames, propName)
			end

			for propName, propType in pairs(classPatches.Add) do
				local prop = propMap[propName]

				if prop then
					local serial = prop.Serialization
					serial.CanSave = true
					serial.CanLoad = true
				else
					propMap[propName] = createProperty(propName, propType)
					table.insert(propNames, propName)
				end
			end

			local firstLine = true
			class.PropertyMap = propMap

			local ancestor = class
			local diffProps = {}

			while object do
				ancestor = classes[ancestor.Superclass]

				if not ancestor then
					break
				end

				local inheritProps = ancestor.PropertyMap
				local inherited = ancestor.Inherited

				local baseObject = if inherited then inherited.Object else nil

				if inheritProps and baseObject then
					for name, prop in pairs(inheritProps) do
						local tags = getTags(prop)

						if tags.ReadOnly then
							continue
						end

						local gotPropValue, propValue = pcall(function()
							return object[name]
						end)

						local gotBaseValue, baseValue = pcall(function()
							return baseObject[name]
						end)

						if gotBaseValue and gotPropValue then
							if propValue ~= baseValue then
								diffProps[name] = propValue
							end
						end
					end
				end
			end

			if classTags.Service or next(diffProps) then
				local headerFormat = "public %s()"

				if next(diffProps) then
					headerFormat ..= " : base()"
				end

				writeLine(headerFormat, className)
				openStack()

				if classTags.Service then
					writeLine("IsService = true;")

					if next(diffProps) then
						writeLine()
					end
				end

				if next(diffProps) then
					local diffNames = {}

					for name in pairs(diffProps) do
						table.insert(diffNames, name)
					end

					table.sort(diffNames)

					for i, name in ipairs(diffNames) do
						local value = diffProps[name]
						local valueType = typeof(value)
						local formatFunc = getFormatFunction(valueType)

						if formatFunc ~= formatting.Null then
							local result = formatFunc(value)

							if result == "" then
								result = tostring(value)
							end

							writeLine("%s = %s;", name, result)
						end
					end
				end

				closeStack()
			end

			table.sort(propNames)

			for j, propName in ipairs(propNames) do
				local prop = propMap[propName]
				local propTags = getTags(prop)

				local serial = prop.Serialization
				local typeData = prop.ValueType

				local category = typeData.Category
				local valueType = typeData.Name

				local redirect = redirectProps[propName]
				local couldSave = (serial.CanSave or propTags.Deprecated or redirect)

				if serial.CanLoad and couldSave then
					if firstLine and (classTags.Service or next(diffProps)) then
						writeLine()
					end

					local name = propName
					local default = ""

					if propName == className then
						name = name .. "_"
					end

					if valueType == "int64" then
						valueType = "long"
					elseif valueType == "BinaryString" then
						valueType = "byte[]"
					elseif valueType == "Font" and category ~= "Enum" then
						valueType = "FontFace"
					end

					local first = name:sub(1, 1)

					if first == first:lower() then
						local pascal = first:upper() .. name:sub(2)
						if propMap[pascal] ~= nil and propTags.Deprecated then
							redirect = pascal
						end
					end

					if redirect then
						local get, set, flag

						if typeof(redirect) == "string" then
							get = redirect
							set = redirect .. " = value"

							if redirect == "value" then
								set = "this." .. set
							end
						else
							get = redirect.Get
							set = redirect.Set
							flag = redirect.Flag
						end

						if not firstLine and set then
							writeLine()
						end

						if propTags.Deprecated then
							writeLine("[Obsolete]")
						end

						if set then
							if flag then
								writeLine("public %s %s %s", flag, valueType, name)
							else
								writeLine("public %s %s", valueType, name)
							end

							openStack()
							writeLine("get => %s;", get)

							if set:find("\n") then
								writeLine()

								writeLine("set")
								openStack()

								for line in set:gmatch("[^\r\n]+") do
									writeLine(line)
								end

								closeStack()
							else
								writeLine("set => %s;", set)
							end

							closeStack()
						else
							writeLine("public %s %s => %s;", valueType, name, get)
						end

						if j ~= #propNames and set then
							writeLine()
						end
					else
						local value = classPatches.Defaults[propName]
						local gotValue = (value ~= nil)

						if not gotValue then
							gotValue, value = pcall(function()
								return object[propName]
							end)
						end

						if not gotValue and category ~= "Class" then
							-- Fallback to implicit defaults

							if numberTypes[valueType] then
								value = 0
								gotValue = true
							elseif stringTypes[valueType] then
								value = ""
								gotValue = true
							elseif valueType == "SharedString" then
								value = "yuZpQdnvvUBOTYh1jqZ2cA=="
								gotValue = true
							elseif category == "DataType" then
								local DataType = env[valueType]

								if DataType and typeof(DataType) == "table" and not rawget(env, valueType) then
									pcall(function()
										value = DataType.new()
										gotValue = true
									end)
								end
							elseif category == "Enum" then
								local enum = Enum[valueType]
								local lowestId = math.huge
								local lowest

								for _, item in pairs(enum:GetEnumItems()) do
									local itemValue = item.Value

									if itemValue < lowestId then
										lowest = item
										lowestId = itemValue
									end
								end

								if lowest then
									value = lowest
									gotValue = true
								end
							end

							local id = string.format("%s.%s", className, propName)
							local src = string.format("[%s]", script.Parent:GetFullName())

							if gotValue then
								warn(src, "Fell back to implicit value for property:", id)
							else
								warn(
									src,
									"!! Could not figure out default value for property:",
									id,
									"value error was:",
									value
								)
							end
						end

						if gotValue then
							local formatKey = if category == "Enum" then "Enum" else valueType
							local formatFunc = getFormatFunction(formatKey)

							if formatFunc == formatting.Null then
								local literal = typeof(value)
								formatFunc = getFormatFunction(literal)
							end

							local result

							if formatFunc then
								if typeof(formatFunc) == "string" then
									result = formatFunc
								else
									result = formatFunc(value)
								end
							end

							if result == "" then
								result = nil
							end

							if result ~= nil then
								default = " = " .. result
							end

							if formatFunc == formatting.EnumItem then
								local enumName = tostring(value.EnumType)
								enumMap[enumName] = true
							end
						end

						if className == "Sound" and propName == "EmitterSize" then
							-- .____.
							propTags.Deprecated = false
						end

						if propTags.Deprecated then
							if not firstLine then
								writeLine()
							end

							writeLine("[Obsolete]")
						end

						writeLine("public %s %s%s;", valueType, name, default)

						if propTags.Deprecated and j ~= #propNames then
							writeLine()
						end
					end

					firstLine = false
				end
			end

			closeStack()

			if i ~= #classNames then
				writeLine()
			end
		end
	end

	closeStack()
	exportStream("Classes")

	return enumMap
end

local function generateEnums(whiteList)
	local version = getfenv().version():gsub("%. ", ".")
	clearStream()

	writeLine("// Auto-generated list of Roblox enums.")
	writeLine("// Updated as of %s", version)
	writeLine()

	writeLine("namespace RobloxFiles.Enums")
	openStack()

	local enums = Enum:GetEnums()

	for i, enum in ipairs(enums) do
		local enumName = tostring(enum)

		if whiteList and not whiteList[enumName] then
			continue
		end

		writeLine("public enum %s", enumName)
		openStack()

		local enumItems = enum:GetEnumItems()
		local lastValue = -1
		local mapped = {}

		table.sort(enumItems, function(a, b)
			return a.Value < b.Value
		end)

		for j, enumItem in ipairs(enumItems) do
			local text = ""
			local comma = ","

			local name = enumItem.Name
			local value = enumItem.Value

			if not mapped[value] then
				if (value - lastValue) ~= 1 then
					text = " = " .. value
				end

				if j == #enumItems then
					comma = ""
				end

				lastValue = value
				mapped[value] = true

				writeLine("%s%s%s", name, text, comma)
			end
		end

		closeStack()

		if i ~= #enums then
			writeLine()
		end
	end

	closeStack()
	exportStream("Enums")
end

local function generateAll()
	local enumList = generateClasses()
	generateEnums(enumList)
end

if plugin then
	button.Click:Connect(generateAll)
else
	generateAll()
end

if game.Name:sub(1, 9) == "Null.rbxl" then
	generateAll()
end