Battle Pet GUID Detector

BattlePetGuidDetector.lua

local BattlePetTrackerMixin = {};

function BattlePetTrackerMixin:OnLoad()
    self:RegisterUnitEvent("UNIT_SPELLCAST_SUCCEEDED", "player", "");
    self:RegisterEvent("COMPANION_UPDATE");
    self:SetScript("OnEvent", function(_, ...) self:OnEvent(...) end);

    self.currentServerId = nil;
    self.currentInstanceId = nil;
    self.currentZoneUid = nil;
    self.lastCastTime = nil;
    self.companionJournalGuid = nil;
    self.companionUnitGuid = nil;
end

function BattlePetTrackerMixin:OnEvent(event, arg1, ...)
    if event == "UNIT_SPELLCAST_SUCCEEDED" then
        self:OnPlayerSpellCastSucceeded(...);
    elseif event == "COMPANION_UPDATE" and arg1 == "CRITTER" then
        self:OnCompanionUpdate();
    end
end

function BattlePetTrackerMixin:OnPlayerSpellCastSucceeded(castGuid, spellId)
    local _, _, serverId, instanceId, zoneUid, _, castUid = string.split("-", castGuid);

    serverId = tonumber(serverId);
    instanceId = tonumber(instanceId);
    zoneUid = tonumber(zoneUid);

    if serverId == 0 then
        -- Local spell cast that fizzled due to casting requirements.
        return;
    end

    local castOffset = bit.band(tonumber(string.sub(castUid, -6), 16), 0x7fffff);
    local castEpoch = GetServerTime() - (GetServerTime() % 2^23);
    local castTime = castEpoch + castOffset;

    self.currentServerId = serverId;
    self.currentInstanceId = instanceId;
    self.currentZoneUid = zoneUid;
    self.lastCastTime = castTime;

    DevTools_Dump({{
        spellId = spellId,
        currentServerId = self.currentServerId,
        currentInstanceId = self.currentInstanceId,
        currentZoneUid = self.currentZoneUid,
        lastCastTime = date("%Y-%m-%d %H:%M:%S", self.lastCastTime),
    }});
end

function BattlePetTrackerMixin:OnCompanionUpdate()
    local companionJournalGuid = C_PetJournal.GetSummonedPetGUID();

    if self.companionJournalGuid == companionJournalGuid then
        return;
    end

    self.companionJournalGuid = companionJournalGuid;
    self.companionUnitGuid = nil;

    if not self.companionJournalGuid or not self.lastCastTime then
        return;
    end

    local serverId = self.currentServerId;
    local instanceId = self.currentInstanceId;
    local zoneUid = self.currentZoneUid;
    local npcId = select(11, C_PetJournal.GetPetInfoByPetID(self.companionJournalGuid));
    local castTime = self.lastCastTime % 2^23;

    for spawnIndex = 0, 16 do -- Arbitrary limit.
        local spawnUidLow = bit.band(castTime, 0xfffff);
        local spawnUidHigh = bit.bor(bit.lshift(spawnIndex, 3), bit.rshift(castTime, 20));
        local guid = string.format("Creature-0-%d-%d-%d-%d-%05X%05X", serverId, instanceId, zoneUid, npcId, spawnUidHigh, spawnUidLow);

        GameTooltip:SetOwner(WorldFrame, "ANCHOR_NONE");
        GameTooltip:SetHyperlink("unit:" .. guid);
        GameTooltip:Show();

        if GameTooltip:GetUnit() then
            self.companionUnitGuid = guid;
            break;
        end
    end

    GameTooltip:Hide();

    DevTools_Dump({{
        battlePetGuid = self.companionJournalGuid,
        unitGuid = self.companionUnitGuid or UnitGUID("none"),
        castTime = date("%Y-%m-%d %H:%M:%S", self.lastCastTime),
        serverTime = date("%Y-%m-%d %H:%M:%S", GetServerTime()),
    }});
end

local frame = Mixin(CreateFrame("Frame"), BattlePetTrackerMixin);
frame:OnLoad();