WeakAura Patterns

function (states, event, ...)
  -- for the sake of a high-frequency example
  if event == "COMBAT_LOG_EVENT_UNFILTERED" then 
    -- do evil

    -- whatever your criteria are
    if matchesCriteria or aggregatedData then
      aura_env.queue()
    end

    -- important to prevent these events from updating the aura
    return false
  end

  if event == aura_env.customEventName then
    local id = ...

    -- make sure the event is actually from us
    if id ~= aura_env.id then
      return false
    end

    -- perform state update based on either the payload from the custom event or aggregated data
    return true
  end

  -- ignore STATUS, OPTIONS etc.
  return false
end

aura_env.customEventName = "SOMETHING_DEFINITELY_UNIQUE"
aura_env.timer = nil

function aura_env.queue()
 if aura_env.timer then
  if not aura_env.timer:IsCancelled() then
   aura_env.timer:Cancel()
  end

  aura_env.timer = nil
 end

 -- 3 is seconds here, whatever you need. 0 means next frame
 aura_env.timer = C_Timer.NewTimer(3, function()
  WeakAuras.ScanEvents(aura_env.customEventName, aura_env.id)
 end)
end

--- CLEU:SPELL_DAMAGE:SPELL_MISSED, XEPHUI_BREATH_OF_EONS_ANNOUNCER
function (event, ...)
 if event == "COMBAT_LOG_EVENT_UNFILTERED" then
  local _, subEvent = ...
  local key = nil
  local addition = 0

  if subEvent == "SPELL_DAMAGE" then
   local _, _, _, sourceGUID, _, _, _, _, _, _, _, spellId, _, _, amount, _, _, _, _, absorbed = ...

   if spellId == 409632 then
    key = sourceGUID
    addition = amount + (absorbed or 0) -- to account for partial absorbs
   end
  elseif subEvent == "SPELL_MISSED" then
   local _, _, _, sourceGUID, _, _, _, _, _, _, _, spellId, _, _, missType, _, amount = ...

   if missType == "ABSORB" and spellId == 409632 then
    key = sourceGUID
    addition = amount
   end
  end

  if addition > 0 and key then
   aura_env.bySource[key] = aura_env.bySource[key] or 0
   aura_env.bySource[key] = aura_env.bySource[key] + addition
   aura_env.queue()
  end

  return false
 end

 if event == aura_env.customEventName then
  local id = ...

  if id ~= aura_env.id then
   return false
  end

  aura_env.timer = nil

  local message = aura_env.getMessage()

  if aura_env.config.announce then
   SendChatMessage(message, "SAY")
  else
   print(message)
  end

  return false
 end

 return false
end

aura_env.customEventName = "XEPHUI_BREATH_OF_EONS_ANNOUNCER"
aura_env.timer = nil

---@type table<string, number>
aura_env.bySource = {}

function aura_env.queue()
 if aura_env.timer then
  if not aura_env.timer:IsCancelled() then
   aura_env.timer:Cancel()
  end

  aura_env.timer = nil
 end

 -- 3 seconds here to definitely catch all events which may be significantly delayed based on debuff application time
 aura_env.timer = C_Timer.NewTimer(3, function()
  WeakAuras.ScanEvents(aura_env.customEventName, aura_env.id)
 end)
end

-- custom formatter for float precision purposes, Blizz provides a similar function but it truncates
---@param number number
---@return string
local function formatNumber(number)
 if number > 1000000 then
  return string.format("%1.2fM", number / 1000000)
 end

 if number > 1000 then
  return string.format("%1.2fK", number / 1000)
 end

 return number
end

local baseBlueprint = C_Spell.GetSpellName(403631) .. " hit for %s!"
local maxContributorBlueprint = "Highest contributor: %s with %s (%s%%)"

---@return string
function aura_env.getMessage()
 local total = 0
 local individualMax = 0
 local maxSource = nil

 for sourceGUID, amount in pairs(aura_env.bySource) do
   total = total + amount

   if amount > individualMax then
    individualMax = amount
    maxSource = sourceGUID
   end
 end

 table.wipe(aura_env.bySource)

 local base = string.format(baseBlueprint, formatNumber(total))

 if aura_env.config.includeContributor and individualMax > 0 and maxSource ~= nil then
  local token = UnitTokenFromGUID(maxSource)
  local name = token and UnitName(token) or nil

  if name then
   return string.format(
    base .. " " .. maxContributorBlueprint,
    name,
    formatNumber(individualMax),
    string.format("%.2f", individualMax / total * 100)
   )
  end
 end

 return base
end