Combustion Separate Digits

function combustion.OnUpdate()
    local amount = GetCombustionTotal()
    if combustionConfig.combatHide and amount == 0 and not UnitAffectingCombat("player") then
        combustion.frame:Hide()
        combatHidden = true
    else
        if amount >= turnGreenDps then
            combustion.FontString:SetFont(combustionConfig.font, combustionConfig.fontSize, "THICKOUTLINE")
            combustion.FontString:SetTextColor(0,1,0)
        elseif amount >= turnYellowDps then
            combustion.FontString:SetFont(combustionConfig.font, combustionConfig.fontSize, "OUTLINE")
            combustion.FontString:SetTextColor(1,1,0)
        else
            combustion.FontString:SetFont(combustionConfig.font, combustionConfig.fontSize, "OUTLINE")
            combustion.FontString:SetTextColor(1,0,0)
        end

        function format_thousand(v)
            local s = string.format("%d", math.floor(v))
            local pos = string.len(s) % 3
            if pos == 0 then pos = 3 end
            return string.sub(s, 1, pos)
            .. string.gsub(string.sub(s, pos+1), "(...)", ",%1")
        end

    combustion.FontString:SetText(format_thousand(amount))

    end

end