pfUI:RegisterModule("raid", "vanilla:tbc", function ()
  -- do not go further on disabled UFs
  if C.unitframes.disable == "1" then return end

  local rawborder, default_border = GetBorderSize("unitframes")

  pfUI.uf.raid = CreateFrame("Button","pfRaid",UIParent)

  pfUI.uf.raid.tanksfirst = {
    ["PF_TANK_TOGGLE"] = { T["Toggle as Tank"], "toggleTank" }
  }

  -- no tank order for now, just "all tanks first"
  pfUI.uf.raid.tankrole = { }

  function pfUI.uf.raid:UpdateConfig()
    for i=1, 40 do
      pfUI.uf.raid[i]:UpdateConfig()
    end
  end

  for r=1, 8 do
    for g=1, 5 do
      local i = g + 5*(r-1)
      pfUI.uf.raid[i] = pfUI.uf:CreateUnitFrame("Raid", i, C.unitframes.raid)
      pfUI.uf.raid[i]:UpdateFrameSize()

      local spacing = pfUI.uf.raid[i].config.pspace
      local width = pfUI.uf.raid[i].config.width
      local height = pfUI.uf.raid[i].config.height
      local pheight = pfUI.uf.raid[i].config.pheight
      local real_height = height + spacing + pheight + 2*default_border

      pfUI.uf.raid[i]:SetPoint("BOTTOMLEFT", (r-1) * (width+3*default_border) + 5, C.chat.left.height + default_border + 10 + (g-1)*(real_height+3*default_border))
      UpdateMovable(pfUI.uf.raid[i])
    end
  end


  local function SetRaidIndex(frame, id)
    frame.id = id

    if frame.SetAttribute and RegisterStateDriver then
      frame:SetAttribute("unit", UnitName("raid" .. id))
      frame.visibilitycondition = string.format("[target=%s,exists] show; hide", id > 0 and UnitName("raid" .. id) or "__NONE__")
      RegisterStateDriver(frame, 'visibility', frame.visibilitycondition)
    else
      if id > 0 then frame:Show() else frame:Hide() end
      pfUI.uf:RefreshUnit(frame, "all")
    end
  end

  -- add units to the beginning of their groups
  function pfUI.uf.raid:AddUnitToGroup(index, group)
    for subindex = 1, 5 do
      local ids = subindex + 5*(group-1)
      if pfUI.uf.raid[ids].id == 0 and pfUI.uf.raid[ids].config.visible == "1" then
        SetRaidIndex(pfUI.uf.raid[ids], index)
        return
      end
    end
  end

  pfUI.uf.raid:Hide()
  pfUI.uf.raid:RegisterEvent("RAID_ROSTER_UPDATE")
  pfUI.uf.raid:RegisterEvent("VARIABLES_LOADED")
  pfUI.uf.raid:SetScript("OnEvent", function() this:Show() end)
  pfUI.uf.raid:SetScript("OnUpdate", function()
    -- skip during combat
    if InCombatLockdown and InCombatLockdown() then return end

    -- clear all existing frames
    for i=1, 40 do SetRaidIndex(pfUI.uf.raid[i], 0) end

    -- sort tanks into their groups
    for i=1, GetNumRaidMembers() do
      local name, _, subgroup  = GetRaidRosterInfo(i)
      if name and pfUI.uf.raid.tankrole[name] then
        pfUI.uf.raid:AddUnitToGroup(i, subgroup)
      end
    end

    -- sort players into roster
    for i=1, GetNumRaidMembers() do
      local name, _, subgroup  = GetRaidRosterInfo(i)
      if name and not pfUI.uf.raid.tankrole[name] then
        pfUI.uf.raid:AddUnitToGroup(i, subgroup)
      end
    end

    this:Hide()
  end)

  -- raid popup option to toggle tank role
  local iupm = table.getn(UnitPopupMenus["RAID"])
  for label, data in pairs(pfUI.uf.raid.tanksfirst) do
    UnitPopupButtons[label] = { text = TEXT(data[1]), dist = 0 }
    table.insert(UnitPopupMenus["RAID"], iupm-1, label)
  end

  hooksecurefunc("UnitPopup_OnClick", function()
    local dropdownFrame = _G[UIDROPDOWNMENU_INIT_MENU]
    local button = this.value
    local unit = dropdownFrame.unit
    local name = dropdownFrame.name

    if button and pfUI.uf.raid.tanksfirst[button] and name then
      pfUI.uf.raid.tankrole[name] = not pfUI.uf.raid.tankrole[name]
      pfUI.uf.raid:Show()
    end
  end)
end)