h2-mod/data/ui_scripts/mods/loading.lua

game:addlocalizedstring("MENU_MODS", "MODS")
game:addlocalizedstring("MENU_MODS_DESC", "Load installed mods.")
game:addlocalizedstring("LUA_MENU_MOD_DESC_DEFAULT", "Load &&1.")
game:addlocalizedstring("LUA_MENU_MOD_DESC", "&&1\nAuthor: &&2\nVersion: &&3")
game:addlocalizedstring("LUA_MENU_OPEN_STORE", "Open store")
game:addlocalizedstring("LUA_MENU_OPEN_STORE_DESC", "Download and install mods.")
game:addlocalizedstring("LUA_MENU_LOADED_MOD", "Loaded mod: ^3&&1")
game:addlocalizedstring("LUA_MENU_AVAILABLE_MODS", "Available mods")
game:addlocalizedstring("LUA_MENU_UNLOAD", "Unload")
game:addlocalizedstring("LUA_MENU_UNLOAD_DESC", "Unload the currently loaded mod.")

function createdivider(menu, text)
	local element = LUI.UIElement.new( {
		leftAnchor = true,
		rightAnchor = true,
		left = 0,
		right = 0,
		topAnchor = true,
		bottomAnchor = false,
		top = 0,
		bottom = 33.33
	})

	element.scrollingToNext = true
	element:addElement(LUI.MenuBuilder.BuildRegisteredType("h1_option_menu_titlebar", {
		title_bar_text = Engine.ToUpperCase(text)
	}))

	menu.list:addElement(element)
end

function string:truncate(length)
	if (#self <= length) then
		return self
	end

	return self:sub(1, length - 3) .. "..."
end

LUI.addmenubutton("main_campaign", {
	index = 6,
	text = "@MENU_MODS",
	description = Engine.Localize("@MENU_MODS_DESC"),
	callback = function()
		LUI.FlowManager.RequestAddMenu(nil, "mods_menu")
	end
})

function getmodname(path)
	local name = path
	local desc = Engine.Localize("@LUA_MENU_MOD_DESC_DEFAULT", name)
	local infofile = path .. "/info.json"

	if (io.fileexists(infofile)) then
		pcall(function()
			local data = json.decode(io.readfile(infofile))
			desc = Engine.Localize("@LUA_MENU_MOD_DESC", 
				data.description, data.author, data.version)
			name = data.name
		end)
	end

	return name, desc
end

LUI.MenuBuilder.m_types_build["mods_menu"] = function(a1)
	local menu = LUI.MenuTemplate.new(a1, {
		menu_title = "@MENU_MODS",
		exclusiveController = 0,
		menu_width = 400,
		menu_top_indent = LUI.MenuTemplate.spMenuOffset,
		showTopRightSmallBar = true
	})

	menu:AddButton("@LUA_MENU_OPEN_STORE", function()
		if (LUI.MenuBuilder.m_types_build["mod_store_menu"]) then
			LUI.FlowManager.RequestAddMenu(nil, "mod_store_menu")
		end
	end, nil, true, nil, {
		desc_text = Engine.Localize("@LUA_MENU_OPEN_STORE_DESC")
	})

	local modfolder = game:getloadedmod()
	if (modfolder ~= "") then
		createdivider(menu, Engine.Localize("@LUA_MENU_LOADED_MOD", getmodname(modfolder):truncate(24)))

		menu:AddButton("@LUA_MENU_UNLOAD", function()
			game:executecommand("unloadmod")
		end, nil, true, nil, {
			desc_text = Engine.Localize("@LUA_MENU_UNLOAD_DESC")
		})
	end

	createdivider(menu, Engine.Localize("@LUA_MENU_AVAILABLE_MODS"))

	if (io.directoryexists("mods")) then
		local mods = io.listfiles("mods/")
		for i = 1, #mods do
			if (io.directoryexists(mods[i]) and not io.directoryisempty(mods[i])) then
				local name, desc = getmodname(mods[i])

				if (mods[i] ~= modfolder) then
					game:addlocalizedstring(name, name)
					menu:AddButton(name, function()
						game:executecommand("loadmod " .. mods[i])
					end, nil, true, nil, {
						desc_text = desc
					})
				end
			end
		end
	end
	
	menu:AddBackButton(function(a1)
		Engine.PlaySound(CoD.SFX.MenuBack)
		LUI.FlowManager.RequestLeaveMenu(a1)
	end)

	LUI.Options.InitScrollingList(menu.list, nil)
	menu:CreateBottomDivider()
	menu.optionTextInfo = LUI.Options.AddOptionTextInfo(menu)

	return menu
end