Inserting a line in GameTooltip at arbitrary position?

[LudiusMaximus]

I want to put an extra line in the item tooltip directly beneath the "Sell price" line.

I am hooking OnTooltipSetItem to do so:

GameTooltip:HookScript("OnTooltipSetItem", function(self)
  -- my code
end)

The problem is that I have other addons running which also append their info to the item tooltip.
I guess there is no way to enforce that my addon gets to hook its script first, unless I put it into the optional dependencies of the other addons?

If so, is there another option than scanning the content of the current GameTooltip line by line and inserting my new line after the line beginning with SELL_PRICE?

What would be the most efficient way to do this?
Do I really have to read every line from GameTooltip to a new tooltip or table, then do a GameTooltip:ClearLines() and then GameTooltip:AddLine() everything back?

[Seerah]

No, just everything after where you want your text. Just change the text using :SetText() on the line you want, and then use :SetText() again for every line after that. (You might need to end with an AddLine().)

/edit: but I'd check to see if the last line in the tooltip is the sell price first before doing all that

[LudiusMaximus]

Thanks a lot, this helped me a great deal already.

But copying a tooltip line is not so straight forward, is it?

First of all, I have to check if it is a single or double line by checking

if (_G[self:GetName().."TextRight"..i]:GetText()) then

And then I have to not just copy the text content but also the formating.

For instance, if I want to duplicate the last line, I would do:

local copyText = _G["GameTooltipTextLeft"..GameTooltip:NumLines()]:GetText()
local copyR, copyG, copyB = _G["GameTooltipTextLeft"..GameTooltip:NumLines()]:GetTextColor()

GameTooltip:AddLine(copyText, copyR, copyG, copyB)

But what about the wrapText attribute of a tooltip line?
I could not find the equivalent to GetText() and GetTextColor() for that.

I tried _G["GameTooltipTextLeft"..GameTooltip:NumLines()]:CanNonSpaceWrap() but this always returns false.
EDIT: The same for GetIndentedWordWrap().

[LudiusMaximus]

When I apply SetText() to a tooltip line like

_G["GameTooltipTextLeft1"]:SetText("bla", 1, 0, 0, 1, true)

it does not even change the text colour. Only the text is updated.

So if I want to have the same text colours in the modified tooltip, I would have to built my copy tooltip from scratch only using AddLine() and AddDoubleLine().


EDIT: This is not viable either. When I do GameTooltip:ClearLines() and refill the tooltip with my stored plus added lines, future calls of GameTooltip:GetItem() will only get nil, as the item is apparently cleared by ClearLines().

I can overcome this by

local originalGetItem = GameTooltip.GetItem
GameTooltip:HookScript("OnHide", function(self)
  GameTooltip.GetItem = originalGetItem
end)

and

local name, link = GameTooltip:GetItem()
GameTooltip:ClearLines()
GameTooltip.GetItem = function(self) return name, link end

But this is getting more and more cumbersome...

[SDPhantom]

A simpler way would be to wait until later in the loading process to hook the tooltip and create a prehook the old fashioned way.

local loader=CreateFrame("Frame");
loader:RegisterForEvents("PLAYER_LOGIN");-- Register for an event that appears late in the loading process. This makes it more likely our hook is the last to be set up
loader:SetScript("OnEvent",function()
    local oldscript=GameTooltip:GetScript("OnTooltipSetItem");--    Save any previously registered scripts
    GameTooltip:SetScript("OnTooltipSetItem",function(self,...)--   Futureproofing, support extra args to pass to previous scripts
--      Add your text here
 
--      Run any other addons' functions
        if oldscript then return oldscript(self,...); end
    end);
end);

This is done because GameTooltip:HookScript() sets up a posthook, meaning the function you give it runs after any script that's already there. A prehook in contrast runs before any existing function. No protected function should be run from tooltip code, so taint shouldn't be an issue here.

In any occasion, trying to place your addon's text in a certain spot in the tooltip opens up race conditions competing with any other addon that might have that same design choice. The best and most efficient option is to let it be and do nothing.

[LudiusMaximus]

@SDPhantom: Thanks, but when I do a pre-hook of OnTooltipSetItem(), will there be anything at all in the GameTooltip for me to modify? I do not care about what other addons my later append but I want to rearrange the original GameTooltip content which the BlizzardUI has put there.

Anyway, here is how I solved this now by manually copy-pasting every line.
Unfortunately, I still do not know how to copy the "intended word wrap" of a tooltip line.
But I have thus far not seen any case where the wrap would have been set to false, so I am setting it to true by default for every copied line.

-- Have to override GameTooltip.GetItem() after calling ClearLines().
-- This will restore the original after the tooltip is closed.
local originalGetItem = GameTooltip.GetItem
GameTooltip:HookScript("OnHide", function(self)
  GameTooltip.GetItem = originalGetItem
end)
 
 
 
GameTooltip:HookScript("OnTooltipSetItem", function(self)
 
  -- Only interested in tooltips with money frame, as I want to put my text below this.
  if not self.shownMoneyFrames then return end
 
  -- The money frame is anchored to a blank line of the tootlip.
  -- Find out which line it is and what the sell price is.
  local moneyFrameLineNumber = nil
  local money = nil
 
  -- Check all shown money frames of the tooltip.
  -- (There is normally only one, except other addons have added more.)
  for i = 1, self.shownMoneyFrames, 1 do
 
    local moneyFrameName = self:GetName().."MoneyFrame"..i
 
    -- If the money frame's PrefixText is "SELL_PRICE:", we assume it is the one we are looking for.
    if _G[moneyFrameName.."PrefixText"]:GetText() == string_format("%s:", SELL_PRICE) then
      local _, moneyFrameAnchor = _G[moneyFrameName]:GetPoint(1)
      
      -- Get line number and amount of money.
      moneyFrameLineNumber = tonumber(string_match(moneyFrameAnchor:GetName(), self:GetName().."TextLeft(%d+)"))
      money = _G[moneyFrameName].staticMoney
 
      break
    end
    
  end
 
 
  if not moneyFrameLineNumber then return end
 
 
  -- Store all text and text colours of the original tooltip lines.
  -- TODO: Unfortunately I do not know how to store the "indented word wrap".
  --       Therefore, we have to put wrap=true for all lines in the new tooltip.
  local leftText = {}
  local leftTextR = {}
  local leftTextG = {}
  local leftTextB = {}
  
  local rightText = {}
  local rightTextR = {}
  local rightTextG = {}
  local rightTextB = {}
  
  -- Store the number of lines for after ClearLines().
  local numLines = self:NumLines()
  
  -- Store all lines of the original tooltip.
  for i = 1, numLines, 1 do
    leftText[i] = _G[self:GetName().."TextLeft"..i]:GetText()
    leftTextR[i], leftTextG[i], leftTextB[i] = _G[self:GetName().."TextLeft"..i]:GetTextColor()
 
    rightText[i] = _G[self:GetName().."TextRight"..i]:GetText()
    rightTextR[i], rightTextG[i], rightTextB[i] = _G[self:GetName().."TextRight"..i]:GetTextColor()
  end
  
  
  self:ClearLines()
  -- Got to override GameTooltip.GetItem(), such that other addons can still use it
  -- to learn which item is displayed. Will be restored after GameTooltip:OnHide() (see above).
  local name, link = self:GetItem()
  self.GetItem = function(self) return name, link end
  
  -- Refill the tooltip with the stored lines plus my added lines.
  for i = 1, moneyFrameLineNumber-1, 1 do
  
    if rightText[i] then
      self:AddDoubleLine(leftText[i], rightText[i], leftTextR[i], leftTextG[i], leftTextB[i], rightTextR[i], rightTextG[i], rightTextB[i])
    else
      -- TODO: Unfortunately I do not know how to store the "indented word wrap".
      --       Therefore, we have to put wrap=true for all lines in the new tooltip.
      self:AddLine(leftText[i], leftTextR[i], leftTextG[i], leftTextB[i], true)
    end
  
  end
 
  -- Set original money frame.
  SetTooltipMoney(self, money, nil, string_format("%s:", SELL_PRICE))
 
  -- Set my new stuff!
  self:AddLine("My new stuff here...")
 
  -- Set the remaining original tooltip lines.
  for i = moneyFrameLineNumber+1, numLines, 1 do
  
    if rightText[i] then
      self:AddDoubleLine(leftText[i], rightText[i], leftTextR[i], leftTextG[i], leftTextB[i], rightTextR[i], rightTextG[i], rightTextB[i])
    else
      -- TODO: Unfortunately I do not know how to store the "indented word wrap".
      --       Therefore, we have to put wrap=true for all lines in the new tooltip.
      self:AddLine(leftText[i], leftTextR[i], leftTextG[i], leftTextB[i], true)
    end
  
  end
  
end
)

[SDPhantom]

Since the "Sell Price" line you're wanting to put your text under is the last line in the standard tooltip text, there is no need to try to manually reconstruct the tooltip when the solution I provided has your code run before anything else does. And yes, all the standard text is there by the time the script is run, otherwise, you'd have addons' text popping up at the top instead of the bottom.

[LudiusMaximus]

All right, thanks for the clarification! Now I understand the difference between SetScript and HookScript. :-D

However, if other Addons use the same method as you suggested, I have again no controll over which one is loaded first, right?

E.g. the author of LibExtraTip (used by TheUndermineJournal) does it like this (LibExtraTip.lua, L545):

-- Called to install/modify a pre-hook on the given tooltip's event
-- Currently we do not need any posthooks on scripts
local function hookscript(tip, script, prehook)
    if not lib.hookStore[tip] then lib.hookStore[tip] = {} end
    local control
    -- check for existing hook
    control = lib.hookStore[tip][script]
    if control then
        control[1] = prehook or control[1]
        return
    end
    -- prepare upvalues
    local orig = tip:GetScript(script)
    control = {prehook}
    lib.hookStore[tip][script] = control
    -- install hook stub
    local stub = function(...)
        local h
        -- prehook
        h = control[1]
        if h then h(...) end
        -- original hook
        if orig then orig(...) end
    end
    tip:SetScript(script, stub)
end

With your code, my lines always get appended after those of TheUndermineJournal.

[LudiusMaximus]

Apparently PLAYER_LOGIN was just not late enough. It works, when I am using a timer to make sure that I am really the last. Thanks again!!

local folderName = ...
local L = LibStub("AceAddon-3.0"):NewAddon(folderName, "AceTimer-3.0")
local startupFrame = CreateFrame("Frame")
startupFrame:RegisterEvent("PLAYER_LOGIN")
startupFrame:SetScript("OnEvent", function(self, event, ...)
  L:ScheduleTimer("initCode", 5.0)
end)
 
function L:initCode()
  -- Save any previously registered scripts.
  local oldscript=GameTooltip:GetScript("OnTooltipSetItem")
  
  -- Futureproofing, support extra args to pass to previous scripts
  GameTooltip:SetScript("OnTooltipSetItem", function(self, ...)
    
    self:AddLine("I am first!")
 
    if oldscript then return oldscript(self, ...) end
  end);
end