local run = false
local tabid = 1
local talentid = 1
local learned = false

local GetFreeTalentPoints = GetUnspentTalentPoints or GetNumUnspentTalents

assert(GetFreeTalentPoints, "No function set for getting unspent talents!")

local function ONUPDATE(self, diff)
    if (not run) then
        return
    end

    if(GetFreeTalentPoints() >= 1) then
        if (tabid <= 3) then
            while (talentid <= GetNumTalents(tabid)) do
                local _, _, tier, column, currentRank, maxRank, _, _ = GetTalentInfo(tabid, talentid)
                if (currentRank < maxRank) then
                    LearnTalent(tabid, talentid)
                    learned = true
                end
                talentid = talentid + 1
                if (talentid <= GetNumTalents(tabid)) then
                    local _, _, nexttier, nextcolumn, nextcurrentRank, nextmaxRank, _, _ = GetTalentInfo(tabid, talentid)
                    if (learned and tier < nexttier) then
                        talentid = talentid - column
                        learned = false
                        return
                    end
                else
                    if (learned) then
                        talentid = talentid - column
                        learned = false
                        return
                    end
                end
                if (learned) then
                    return
                end
            end
            tabid = tabid + 1
            talentid = 1
            learned = false
            return
        end
    end

    run = false
    tabid = 1
    talentid = 1
    runid = 1
end

local timer = CreateFrame("Frame")
timer:SetScript("OnUpdate", ONUPDATE)

local function StartRunning(self)
    run = true
end

assert(LoadAddOn("Blizzard_TalentUI"))
local Button = CreateFrame("Button", "Learn 255 Talents", PlayerTalentFrame, "UIPanelButtonTemplate")
Button:SetPoint("TOP", PlayerTalentFrame, "TOP", 0, -40)
Button:SetText("Learn all talents")
Button:SetSize(120, 25)
Button:SetScript("OnMouseUp", StartRunning)