ServerScriptService.Script:2: attempt to index nil with 'GetMouse' bug?

How to do I fix this bug in my code of "ServerScriptService.Script:2: attempt to index nil with 'GetMouse'" in Line 2?

 local t = 1;
 local mouse = game.Players.LocalPlayer:GetMouse();
 local hrp = game.Players.LocalPlayer.CharacterAdded:Wait():WaitForChild("HumanoidRootPart");
 local bball = game.ServerStorage.PracticeBall
 local rs = game:GetService("RunService").RenderStepped;

 mouse.Button1Down:Connect(function()
     local g = Vector3.new(0, -game.Workspace.Gravity, 0);
     local x0 = hrp.CFrame * Vector3.new(0, 2, -2)

     -- calculate the v0 needed to reach mouse.Hit.p
     local v0 = (mouse.Hit.p - x0 - 0.5*g*t*t)/t;

     local c = bball:Clone();
     c.CanCollide = true;
     c.Anchored = true;
     c.Parent = game.Workspace;

     -- have the ball travel that path
     local nt = 0;
     while (nt < t*2) do
          c.CFrame = CFrame.new(0.5*g*nt*nt + v0*nt + x0); 
              nt = nt + rs:Wait();
     end
 end)