DoubleJumpHandler

local character = script.Parent
local humanoid = character:WaitForChild("Humanoid")

local uis = game:GetService("UserInputService")

local canDoubleJump = false
local hasLanded = true


humanoid.StateChanged:Connect(function(previous, new)

    if new == Enum.HumanoidStateType.Jumping and hasLanded then

        if not canDoubleJump then canDoubleJump = true; hasLanded = false end


    elseif new == Enum.HumanoidStateType.Landed then

        canDoubleJump = false
        hasLanded = true
    end
end)

uis.InputBegan:Connect(function(input, processed)

    if processed then return end

    if input.KeyCode == Enum.KeyCode.Space then

        if canDoubleJump then

            humanoid:ChangeState(Enum.HumanoidStateType.Jumping)
            canDoubleJump = false
        end
    end
end)