WoWInterface SVN oUF_Smee2

local parent = debugstack():match[[\AddOns\(.-)\]]
local global = GetAddOnMetadata(parent, 'X-oUF')
assert(global, 'X-oUF needs to be defined in the parent add-on.')
local oUF = _G[global]

local objects = oUF.objects

local VehicleDriverFrame

local UpdateVehicleSwitch = function(self, attr, value)
        if attr == "unit" then
                self.unit = value

                if self:GetAttribute("normalUnit") == "player" then
                        PlayerFrame.unit = self.unit
                        BuffFrame_Update()
                end
        end
end

local Enable = function(self, unit)
        if self.disallowVehicleSwap or (unit ~= "player" and unit ~= "pet") then return end

        if not VehicleDriverFrame then
                VehicleDriverFrame = CreateFrame("Frame", nil, UIParent, "SecureHandlerStateTemplate")
                RegisterStateDriver(VehicleDriverFrame, "vehicle", "[target=vehicle,exists,bonusbar:5]vehicle;novehicle")
                VehicleDriverFrame:SetAttribute("_onstate-vehicle", [[
                        if newstate == "vehicle" then
                                for idx, frame in pairs(VEHICLE_FRAMES) do
                                        frame:SetAttribute("unit", frame:GetAttribute("vehicleUnit"))
                                end
                        else
                                for idx, frame in pairs(VEHICLE_FRAMES) do
                                        frame:SetAttribute("unit", frame:GetAttribute("normalUnit"))
                                end
                        end
                ]])
                VehicleDriverFrame:Execute([[
                        VEHICLE_FRAMES = newtable()
                ]])
        end

        self:SetAttribute("normalUnit", unit)

        if unit == "player" then
                self:SetAttribute("vehicleUnit", "pet")
        elseif unit == "pet" then
                self:SetAttribute("vehicleUnit", "player")
        end

        VehicleDriverFrame:SetFrameRef("vehicleFrame", self)
        VehicleDriverFrame:Execute([[
                local frame = self:GetFrameRef("vehicleFrame")
                table.insert(VEHICLE_FRAMES, frame)
        ]])

        self:HookScript("OnAttributeChanged", UpdateVehicleSwitch)
end

local Disable = function(self)
        self:SetAttribute("unit", self:GetAttribute("normalUnit"))
        VehicleDriverFrame:SetFrameRef("vehicleFrame", self)
        VehicleDriverFrame:Execute([[
                local frame = self:GetFrameRef("vehicleFrame")
                for idx, value in pairs(VEHICLE_FRAMES) do
                        if value == frame then
                                table.remove(VEHICLE_FRAMES, idx)
                                return
                        end
                end
        ]])
end

oUF:AddElement("VehicleSwitch", nil, Enable, Disable)