
--
--  Overachiever
--    by Tuhljin
--

--Overachiever_Debug = true

local THIS_VERSION = GetAddOnMetadata("Overachiever", "Version")
local THIS_TITLE = GetAddOnMetadata("Overachiever", "Title")

local ACHINFO_NAME = 2

Overachiever = {};

local L = OVERACHIEVER_STRINGS

local CATEGORIES_INDIV_ALL, CATEGORIES_GUILD_ALL, CATEGORIES_ALL
local CATEGORY_EXPLOREROOT, CATEGORIES_EXPLOREZONES
local OptionsPanel
local MadeDraggable_AchFrame, MadeDragSave_AchFrame


-- Overcome problem where GetAchievementInfo throws an error if the achievement ID is invalid:
do
  local GAI = GetAchievementInfo
  function Overachiever.GetAchievementInfo(...)
    if (pcall(GAI, ...)) then
      return GAI(...); -- Calling it again instead of saving values from previous call seems to be better since we would have to deal with new tables, unpack, manipulating the table for unpack to actually work as expected, etc.
      --tremove(achievementInfo, 1)
      --achievementInfo[#achievementInfo+1] = ''; -- Inserting this on the end is necessary for unpack to work as expected if there are any nil values in the table.
      --return unpack(achievementInfo)
    end
  end
end
local GetAchievementInfo = Overachiever.GetAchievementInfo

-- Overcome problem where GetAchievementCriteriaInfo throws an error if the achievement ID or criteria number is invalid:
do
  local GAI = GetAchievementCriteriaInfo
  function Overachiever.GetAchievementCriteriaInfo(...)
    if (pcall(GAI, ...)) then
      return GAI(...); -- Calling it again instead of saving values from previous call seems to be better since we would have to deal with new tables, unpack, manipulating the table for unpack to actually work as expected, etc.
      --tremove(achievementInfo, 1)
      --achievementInfo[#achievementInfo+1] = ''; -- Inserting this on the end is necessary for unpack to work as expected if there are any nil values in the table.
      --return unpack(achievementInfo)
    end
  end
end
local GetAchievementCriteriaInfo = Overachiever.GetAchievementCriteriaInfo


local function copytab(from, to)
  for k,v in pairs(from) do
    if(type(v) == "table") then
      to[k] = {}
      copytab(v, to[k]);
    else
      to[k] = v;
    end
  end
end

local function emptyfunc()  end


local function chatprint(msg, premsg)
  premsg = premsg or "["..THIS_TITLE.."]"
  DEFAULT_CHAT_FRAME:AddMessage("|cff7eff00"..premsg.."|r "..msg, 0.741, 1, 0.467);
end
Overachiever.chatprint = chatprint

local function BuildCategoryInfo()
  Overachiever.UI_GetValidCategories()
  CATEGORY_EXPLOREROOT = GetAchievementCategory(OVERACHIEVER_ACHID.WorldExplorer);
  CATEGORIES_EXPLOREZONES = {};
  local name, parentID
  for i,id in ipairs(CATEGORIES_INDIV_ALL) do
    name, parentID = GetCategoryInfo(id)
    if (parentID == CATEGORY_EXPLOREROOT) then
      CATEGORIES_EXPLOREZONES[#(CATEGORIES_EXPLOREZONES) + 1] = id;
    end
  end
end

local function getSelectedAchievement(ignoreTab, ignoreFilter)
  if (AchievementFrame and (ignoreTab or AchievementFrame.selectedTab == 1)) then
    if (ignoreFilter or ACHIEVEMENTUI_SELECTEDFILTER == AchievementFrame_GetCategoryNumAchievements_All) then
      return AchievementFrameAchievements.selection
    end
    local id = AchievementFrameAchievements.selection
    local _, _, _, complete = GetAchievementInfo(id)
    if ((complete and ACHIEVEMENTUI_SELECTEDFILTER == AchievementFrame_GetCategoryNumAchievements_Complete) or
        (not complete and ACHIEVEMENTUI_SELECTEDFILTER == AchievementFrame_GetCategoryNumAchievements_Incomplete)) then
      return id
    end
  end
end

local function expandCategory(category)
-- Based on part of AchievementFrame_SelectAchievement() in Blizzard_AchievementUI.lua
  for i, entry in next, ACHIEVEMENTUI_CATEGORIES do
    if ( entry.id == category ) then
      entry.collapsed = false;
    elseif ( entry.parent == category ) then
      entry.hidden = false;
    end
  end
  AchievementFrameCategories_Update()
end

local function isAchievementInUI(id, checkNext)
-- Return true if the achievement should be found in the standard UI
  local StartTime
  if (Overachiever_Debug) then  StartTime = debugprofilestop();  end
  if (checkNext) then
    local nextID, completed = GetNextAchievement(id)
    if (nextID and completed) then
      local newID;
      while ( nextID and completed ) do
        newID, completed = GetNextAchievement(nextID);
        if ( completed ) then
          nextID = newID;
        end
      end
      id = nextID;
    end
  end
  local cat = GetAchievementCategory(id)
  for i=1,GetCategoryNumAchievements(cat) do
    if (GetAchievementInfo(cat, i) == id) then
      if (Overachiever_Debug) then  print("- isAchievementInUI:"..(id or "nil")..": TRUE. Took "..(debugprofilestop() - StartTime) .." ms.");  end
      return true
    end
  end
  if (Overachiever_Debug) then  print("- isAchievementInUI:"..(id or "nil")..": FALSE. Took "..(debugprofilestop() - StartTime) .." ms.");  end
  return false
end

local function openToAchievement(id, canToggleTracking)
  assert( (type(id)=="number"), "Invalid achievement ID." )
  if (GetPreviousAchievement(id) or isAchievementInUI(id, true)) then
    local sel
    if (not AchievementFrame or not AchievementFrame:IsShown()) then
      ToggleAchievementFrame()
    elseif (canToggleTracking) then
      sel = getSelectedAchievement()
    end
    if (sel == id) then
      AchievementButton_ToggleTracking(id)
    else
      Overachiever.UI_SelectAchievement(id)
    end
  else
    UIErrorsFrame:AddMessage(L.MSG_ACHNOTFOUND, 1.0, 0.1, 0.1, 1.0)
    --chatprint(L.MSG_ACHNOTFOUND)
  end
end

local function getCategoryID(name)
  local n
  for i,id in ipairs(CATEGORIES_ALL) do
    n = GetCategoryInfo(id)
    if (n == name) then  return id;  end
  end
end

local getAchievementID_cat, getAchievementID_tab
do
  local found
  
  local function get_arg1_argN(n, arg1, ...)
    return arg1, select(n-1, ...)
  end

  function getAchievementID_cat(category, argnum, pattern, anyCase, getAll)
  -- Go over a given category, looking only at achievements that would normally be listed in the UI for the
  -- player character at this time:
    if (getAll) then  found = found and wipe(found) or {};  end
    if (anyCase) then  pattern = strlower(pattern);  end
    local id, ret, anyFound
    for i=1,GetCategoryNumAchievements(category) do
      id, ret = get_arg1_argN(argnum, GetAchievementInfo(category, i))
	  if (not id) then
        -- Absurdly, GetCategoryNumAchievements now seems to be giving the WRONG NUMBER for at least some categories. (Confirmed in WoW 6.2.2. Might have started earlier.)
		-- Consequently, we need to watch for nil IDs and skip them.
      else
        if (anyCase) then
          if (not ret) then
            chatprint("getAchievementID_cat: ret is nil.", "["..THIS_TITLE.." DEBUG]")
            print("category:",category, "index:",i, "argnum:",argnum)
            ret = ''
          else
		  	ret = strlower(ret)
          end
        end
        if ( strfind(ret, pattern, 1, true) ) then
          if (getAll) then
            found[#(found) + 1] = id;
            anyFound = true
          else
            return id;
          end
        end
	  end
    end
    if (anyFound) then
      return found;
    end
  end

  function getAchievementID_tab(tab, argnum, pattern, anyCase, getAll)
  -- Look at achievements whose IDs are in a given table:
    if (getAll) then  found = found and wipe(found) or {};  end
    if (anyCase) then  pattern = strlower(pattern);  end
    local ret, anyFound
    for i,id in ipairs(tab) do
      ret = select(argnum, GetAchievementInfo(id))
      if (anyCase) then  ret = strlower(ret);  end
      if ( strfind(ret, pattern, 1, true) ) then
        if (getAll) then
          found[#(found) + 1] = id;
          anyFound = true
        else
          return id;
        end
      end
    end
    if (anyFound) then
      return found;
    end
  end

end

local function getAchievementID(list, argnum, pattern, anyCase)
  list = list or CATEGORIES_ALL
  if (type(list) == "table") then
    local id
    for i,cat in ipairs(list) do
      id = getAchievementID_cat(cat, argnum, pattern, anyCase)
      if (id) then  return id;  end
    end
  elseif (type(list) == "number") then
    return getAchievementID_cat(list, argnum, pattern, anyCase)
  elseif (type(list) == "string") then
    local cat = getCategoryID(list)
    assert(cat, "Category not found.")
    return getAchievementID_cat(cat, argnum, pattern, anyCase)
  end
end

local searchResults
local function SearchAchievements(list, argnum, pattern, anyCase)
  list = list or CATEGORIES_ALL
  if (type(list) == "table") then
    -- Reuse table to avoid garbage generation
    searchResults = searchResults and wipe(searchResults) or {}
    local tab, anyFound
    for i,cat in ipairs(list) do
      tab = getAchievementID_cat(cat, argnum, pattern, anyCase, true)
      if (tab) then
        for _,v in ipairs(tab) do
          searchResults[#(searchResults) + 1] = v;
          anyFound = true
        end
      end
    end
    if (anyFound) then
      return searchResults;
    end
  elseif (type(list) == "number") then
    return getAchievementID_cat(list, argnum, pattern, anyCase, true)
  elseif (type(list) == "string") then
    local cat = getCategoryID(list)
    assert(cat, "Category not found.")
    return getAchievementID_cat(cat, argnum, pattern, anyCase, true)
  end
end

local function SearchAchievements_tab(list, argnum, pattern, anyCase)
  searchResults = searchResults and wipe(searchResults) or {}
  local tab, anyFound
  for k,sublist in pairs(list) do
    tab = getAchievementID_tab(sublist, argnum, pattern, anyCase, true)
    if (tab) then
      for _,v in ipairs(tab) do
        searchResults[#(searchResults) + 1] = v;
        anyFound = true
      end
    end
  end
  if (anyFound) then  return searchResults;  end
end


local function canTrackAchievement(id, allowCompleted)
  if (GetNumTrackedAchievements() < MAX_TRACKED_ACHIEVEMENTS and  -- WATCHFRAME_MAXACHIEVEMENTS renamed to MAX_TRACKED_ACHIEVEMENTS
       (allowCompleted or not select(4, GetAchievementInfo(id))) ) then
    return true
  end
end

local function setTracking(id, allowCompleted) -- allowCompleted is defunct; WoW UI doesn't allow this. Left here for now just in case.
  if (canTrackAchievement(id, allowCompleted)) then
    AddTrackedAchievement(id)
    if (AchievementFrameAchievements_ForceUpdate) then
      AchievementFrameAchievements_ForceUpdate()
    end
    return true
  end
end

local isGuildAchievement
do
  local GuildCatLookup
  function isGuildAchievement(id)
    if (not GuildCatLookup) then
      GuildCatLookup = {}
      for i,c in ipairs(CATEGORIES_GUILD_ALL) do
        GuildCatLookup[c] = true
      end
    end
    local cat = GetAchievementCategory(id)
    return GuildCatLookup[cat]
  end
end

local isUIInGuildView
do
  local fakeframe
  function isUIInGuildView()
    fakeframe = fakeframe or { border = { SetTexture = emptyfunc, SetTexCoord = emptyfunc } }
    AchievementButton_ToggleMetaView(fakeframe)  -- Done so we can find out what their local variable IN_GUILD_VIEW is currently.
    return fakeframe.guildView
  end
end

local function checkGuildMembersTooltip(frame)
  if (frame.id and not isGuildAchievement(frame.id)) then  return;  end
  local gv = isUIInGuildView()
  if (not gv) then  AchievementFrame_ToggleView();  end  -- Toggle so we're in guild mode so AchievementFrameAchievements_CheckGuildMembersTooltip will work as desired.
  AchievementFrameAchievements_CheckGuildMembersTooltip(frame)
  if (not gv) then  AchievementFrame_ToggleView();  end
end


-- ACHIEVEMENT ID LOOKUP
--------------------------

local getAllAchievements --, getAllAchievementsInCat
do
  local ALL_ACHIEVEMENTS
  function getAllAchievements(catlist)
  -- Retrieve an array of all achievement IDs, including those not normally listed in the UI for this character.
    catlist = catlist or CATEGORIES_ALL
    ALL_ACHIEVEMENTS = ALL_ACHIEVEMENTS or {}
    if (ALL_ACHIEVEMENTS[catlist]) then  return ALL_ACHIEVEMENTS[catlist];  end
    local catlookup = {}
    for i,c in ipairs(catlist) do
      catlookup[c] = true
    end
    local buildlist = {}
    local gap, i, size, id = 0, 0, 0
    --local debug_largestgap = 0
    repeat
      i = i + 1
      id = GetAchievementInfo(i)
      if (id) then
        --if (gap > debug_largestgap) then debug_largestgap = gap; print("high gap:",debug_largestgap); end
        gap = 0
        if (catlookup[GetAchievementCategory(id)]) then  size = size + 1; buildlist[size] = id;  end
      else
        gap = gap + 1
      end
    until (gap > 1000) -- 1000 is arbitrary. As of this writing, the largest gap is 79, but this is more future-safe.
    --print("last ach ID:",buildlist[size], "/ size:",size)
    catlookup = nil
    ALL_ACHIEVEMENTS[catlist] = buildlist
    return buildlist
  end

  --[[
  local ALL_ACHIEVEMENTS_BYCAT
  function getAllAchievementsInCat(cat)
    ALL_ACHIEVEMENTS_BYCAT = ALL_ACHIEVEMENTS_BYCAT or {}
    if (ALL_ACHIEVEMENTS_BYCAT[cat]) then  return ALL_ACHIEVEMENTS_BYCAT[cat];  end
    local tab, size, list = {}, 0, getAllAchievements()
    for i,id in ipairs(list) do
      if (GetAchievementCategory(id) == cat) then  size = size + 1; tab[size] = id;  end
    end
    ALL_ACHIEVEMENTS_BYCAT[cat] = tab
    return tab
  end
  --]]
end

local function BuildCriteriaLookupTab(...)
-- To be called in this fashion: BuildCriteriaLookupTab( <criteriaType1>, <table1>, <saveCriteriaNumber1>[, <criteriaType2>, <table2>, <saveCriteriaNumber2>[, ...]] )
  local num = select("#", ...)
  local list = getAllAchievements() -- Consider CATEGORIES_INDIV_ALL only?
  local _, critType, assetID, a, tab, savenum
  local numc, i
  local GetAchievementCriteriaInfo = GetAchievementCriteriaInfo
  for x,id in ipairs(list) do
    --for i=1,GetAchievementNumCriteria(id) do
    numc = GetAchievementNumCriteria(id)
    i = 1
    repeat
      _, critType, _, _, _, _, _, assetID = GetAchievementCriteriaInfo(id, i)
      if (critType and assetID and assetID ~= 0) then

        for arg=1,num,3 do
          a, tab, savenum = select(arg, ...)
          if (critType == a) then
            if (tab[assetID]) then
              local v = tab[assetID]
              if (type(v) == "table") then
                local size = #v
                v[size+1] = id
                if (savenum) then  v[size+2] = i;  end
              else
                tab[assetID] = { v, id }  -- Safe to assume savenum isn't true since this wasn't already a table
              end
            else
              if (savenum) then
                tab[assetID] = { id, i }
              else
                tab[assetID] = id
              end
            end
          end
        end

      end
      i = i + 1
    until (i > numc or not assetID)
  end
end

local AchLookup_metaach, AchLookup_kill
local function BuildCriteriaLookupTab_check()
  local meta = not AchLookup_metaach and Overachiever_Settings.UI_RequiredForMetaTooltip
  local kill = not AchLookup_kill and Overachiever_Settings.CreatureTip_killed
  if (meta and kill) then
    AchLookup_metaach, AchLookup_kill = {}, {}
    BuildCriteriaLookupTab(8, AchLookup_metaach, nil, 0, AchLookup_kill, true)
    Overachiever.AchLookup_kill = AchLookup_kill
  elseif (meta) then
    AchLookup_metaach = {}
    BuildCriteriaLookupTab(8, AchLookup_metaach)
  elseif (kill) then
    AchLookup_kill = {}
    BuildCriteriaLookupTab(0, AchLookup_kill, true)
    Overachiever.AchLookup_kill = AchLookup_kill
  end
end

-- DRAGGABLE FRAMES
---------------------

local function CheckDraggable_AchFrame(self, key, val, clicked, LoadPos)
  if (AchievementFrame) then
    -- Check if draggable:
    if (Overachiever_Settings.Draggable_AchFrame) then
      if (not MadeDraggable_AchFrame) then
        TjDragIt.EnableDragging(AchievementFrame, AchievementFrameHeader, AchievementFrameCategoriesContainer,
                                AchievementFrameAchievementsContainer, AchievementFrameStatsContainer,
                                Overachiever_SearchFrameContainer, Overachiever_SuggestionsFrameContainer, Overachiever_WatchFrameContainer)
        MadeDraggable_AchFrame = true
      end
    elseif (MadeDraggable_AchFrame) then
      TjDragIt.DisableDragging(AchievementFrame, AchievementFrameHeader, AchievementFrameCategoriesContainer,
                               AchievementFrameAchievementsContainer, AchievementFrameStatsContainer,
                               Overachiever_SearchFrameContainer, Overachiever_SuggestionsFrameContainer, Overachiever_WatchFrameContainer)
      MadeDraggable_AchFrame = nil
    end
    if (key and AchievementFrame:IsShown()) then
    -- If option may have been changed by the user, frame needs to be hidden before changing its attributes.
      HideUIPanel(AchievementFrame)
    end
    -- Check if position saved:
    if (Overachiever_Settings.DragSave_AchFrame) then
      if (not MadeDragSave_AchFrame) then
        if (not Overachiever_CharVars.Pos_AchievementFrame) then
          Overachiever_CharVars.Pos_AchievementFrame = Overachiever_CharVars_Default and Overachiever_CharVars_Default.Pos_AchievementFrame or {}
        end
        TjDragIt.EnablePositionSaving(AchievementFrame, Overachiever_CharVars.Pos_AchievementFrame, LoadPos)
        AchievementFrame:SetAttribute("UIPanelLayout-enabled", false);
        MadeDragSave_AchFrame = true
      end
    elseif (MadeDragSave_AchFrame) then
      TjDragIt.DisablePositionSaving(AchievementFrame)
      AchievementFrame:SetAttribute("UIPanelLayout-enabled", true);
      MadeDragSave_AchFrame = nil
    end
  end
end

local orig_AchievementFrame_OnShow, orig_AchievementFrame_area

local function AchievementUI_FirstShown_post()
  Overachiever.MainFrame:Hide()
  -- Delayed setting the area attribute until now so that if Blizzard_AchievementUI was loaded just before the
  -- AchievementFrame is to be shown, AchievementFrame wouldn't be set as the current UI panel by code in
  -- UIParent.lua, which causes problems when we don't want it to interact with other UI panels in the standard
  -- way. (Set now instead of leaving it out because the player may want it to interact normally again later.)
  if (orig_AchievementFrame_area) then
    UIPanelWindows["AchievementFrame"].area = orig_AchievementFrame_area
    AchievementFrame:SetAttribute("UIPanelLayout-area", orig_AchievementFrame_area);
    orig_AchievementFrame_area = nil
  end
  CheckDraggable_AchFrame(nil, nil, nil, nil, true)
  if (not Overachiever_Settings.DragSave_AchFrame) then
  -- If we aren't saving the position, then re-open the frame to put it in the standard place. (It'll do this
  -- automatically from now on.)
    local prevfunc = AchievementFrame:GetScript("OnHide")
    AchievementFrame:SetScript("OnHide", nil)
    HideUIPanel(AchievementFrame)
    AchievementFrame:SetScript("OnHide", prevfunc)
    prevfunc = AchievementFrame:GetScript("OnShow")
    AchievementFrame:SetScript("OnShow", nil)
    ShowUIPanel(AchievementFrame)
    AchievementFrame:SetScript("OnShow", prevfunc)
  end
end

local function AchievementUI_FirstShown(...)
  AchievementFrame:SetScript("OnShow", orig_AchievementFrame_OnShow)
  --[[ Pre-3.1 method:
  AchievementFrame_OnShow = orig_AchievementFrame_OnShow
  --]]
  orig_AchievementFrame_OnShow = nil
  -- Delayed call to AchievementUI_FirstShown_post() - let everything else process first:
  Overachiever.MainFrame:Show()
  -- Call original function:
  AchievementFrame_OnShow(...)
  AchievementUI_FirstShown = nil
end


-- ACHIEVEMENT HYPERLINK HOOK
-------------------------------

--local orig_SetItemRef = SetItemRef
local orig_ChatFrame_OnHyperlinkShow = ChatFrame_OnHyperlinkShow
ChatFrame_OnHyperlinkShow = function(self, link, text, button, ...)
  if (strsub(link, 1, 11) == "achievement") then
    if (IsControlKeyDown()) then
      local id = strsplit(":", strsub(link, 13));
      id = tonumber(id)
      openToAchievement(id, true)
      return;
    elseif (IsAltKeyDown()) then
      if (not AchievementFrame) then  AchievementFrame_LoadUI();  end
      if (Overachiever_WatchFrame) then
        local id = strsplit(":", strsub(link, 13));
        id = tonumber(id)
        Overachiever_WatchFrame.SetAchWatchList(id, true)
        return;
      end
    end
  end
  return orig_ChatFrame_OnHyperlinkShow(self, link, text, button, ...)
end

-- ACHIEVEMENT TRACKER CHANGES
--------------------------------

local orig_WatchFrameLinkButtonTemplate_OnLeftClick = WatchFrameLinkButtonTemplate_OnLeftClick

WatchFrameLinkButtonTemplate_OnLeftClick = function(self, ...)
  if (self.type == "ACHIEVEMENT") then
    CloseDropDownMenus()
    if (IsShiftKeyDown()) then
      if ( ChatEdit_GetActiveWindow() ) then
        ChatEdit_InsertLink(GetAchievementLink(self.index));
      else
        ChatFrame_OpenChat(GetAchievementLink(self.index));
      end
    else
    -- We prefer an openToAchievement() call instead of a direct AchievementFrame_SelectAchievement() call, so
    -- we do this here instead of calling orig_WatchFrameLinkButtonTemplate_OnLeftClick():
      openToAchievement(self.index)
    end
    return;
  end
  orig_WatchFrameLinkButtonTemplate_OnLeftClick(self, ...)
end

WatchFrame_OpenAchievementFrame = function(button, arg1, arg2, checked)
-- Take over reaction to clicking "Open Achievement" in the watch frame's right-click popup menu, preventing
-- lock ups if tracking an achievement not in the UI as well as using openToAchievement(), which we prefer, instead of
-- a direct AchievementFrame_SelectAchievement() call.
  openToAchievement(arg1)
end

local function TrackerBtnOnEnter(self)
  if (self.type ~= "ACHIEVEMENT") then  return;  end
  GameTooltip:SetOwner(self, "ANCHOR_NONE")
  local x, y = self:GetCenter()
  local w = UIParent:GetWidth() / 3
  if (x > w) then
    GameTooltip:SetPoint("TOPRIGHT", self, "TOPLEFT", -2, 0)
  else
    GameTooltip:SetPoint("TOP", self, "TOP", 0, 0)
    GameTooltip:SetPoint("LEFT", WatchFrame, "RIGHT", -8, 0)
  end
  GameTooltip:SetHyperlink( GetAchievementLink(self.index) )
end

local function TrackerBtnOnLeave()
  GameTooltip:Hide()
end

if (WATCHFRAME_LINKBUTTONS) then --asdf stopgap solution until watch frame can be used properly

	-- Hook current Watch Frame Link Buttons:
	for k, v in pairs(WATCHFRAME_LINKBUTTONS) do
	  v.OverachieverHooked = true
	  v:HookScript("OnEnter", TrackerBtnOnEnter)
	  v:HookScript("OnLeave", TrackerBtnOnLeave)
	end

	-- Hook future Watch Frame Link Buttons when they are created:
	setmetatable(WATCHFRAME_LINKBUTTONS, { __newindex = function(t, k, v)
	  rawset(t, k, v)
	  if (not v.OverachieverHooked) then
		v.OverachieverHooked = true
		v:HookScript("OnEnter", TrackerBtnOnEnter)
		v:HookScript("OnLeave", TrackerBtnOnLeave)
	  end
	end })

end

local function getExplorationAch(zonesOnly, ...)
  local id, cat
  for i = select("#", ...), 1, -1 do
    id = select(i, ...)
    cat = GetAchievementCategory(id)
    if (cat == CATEGORY_EXPLOREROOT) then
      if (not zonesOnly) then  return id;  end
    else
      local _, parentID = GetCategoryInfo(cat)
      if (parentID == CATEGORY_EXPLOREROOT) then
        if ( not zonesOnly or
             -- Eliminate achievements in the category that aren't standard exploration:
             (id ~= OVERACHIEVER_ACHID.MediumRare and id ~= OVERACHIEVER_ACHID.BloodyRare and
              id ~= OVERACHIEVER_ACHID.NorthernExposure and id ~= OVERACHIEVER_ACHID.Frostbitten and
              id ~= OVERACHIEVER_ACHID.StoodInTheFire and id ~= OVERACHIEVER_ACHID.SurveyingTheDamage and
              id ~= OVERACHIEVER_ACHID.WhaleShark) ) then
          return id
        end
      end
    end
  end
end

local AutoTrackedAch_explore

local function AutoTrackCheck_Explore(noClearing)
-- noClearing will evaluate to true when called through TjOptions since it passes an object for this first arg.
  if (Overachiever_Settings.Explore_AutoTrack) then
    local id
    if (not IsInInstance()) then
      local zone = GetRealZoneText()
      if (zone and zone ~= "") then
        id = Overachiever.ExploreZoneIDLookup(zone) or
             getAchievementID(CATEGORIES_EXPLOREZONES, ACHINFO_NAME, zone, true)
      end
    end
    if (id and id > 0) then
      local tracked
      if (GetNumTrackedAchievements() > 0) then
        tracked = AutoTrackedAch_explore and IsTrackedAchievement(AutoTrackedAch_explore) and AutoTrackedAch_explore or
                  getExplorationAch(true, GetTrackedAchievements())
      end
      if (tracked) then
        RemoveTrackedAchievement(tracked)
        if (setTracking(id)) then
          AutoTrackedAch_explore = id
        else
          -- If didn't successfully track new achievement, track previous achievement again:
          AddTrackedAchievement(tracked)
        end
      else
        if (setTracking(id)) then
          AutoTrackedAch_explore = id
        end
      end
    elseif (not noClearing and AutoTrackedAch_explore and IsTrackedAchievement(AutoTrackedAch_explore)) then
      RemoveTrackedAchievement(AutoTrackedAch_explore)
      AutoTrackedAch_explore = nil
    end
  end
end


-- META-CRITERIA TOOLTIP
--------------------------

local orig_AchievementButton_GetMeta

local function MetaCriteriaOnEnter(self)
  local id = self.id
  if (id and type(id) == "number" and id > 0) then  -- Extra checks needed for compatibility with addons like Failchievements.
    GameTooltip:SetOwner(self, "ANCHOR_TOPLEFT")
    local link = GetAchievementLink(id)
    GameTooltip:SetHyperlink(link)
    checkGuildMembersTooltip(self)
    if (GameTooltip:GetBottom() < self:GetTop()) then
      GameTooltip:ClearAllPoints()
      GameTooltip:SetPoint("TOPLEFT", self, "BOTTOMLEFT")
    end
  -- If for some reason the ID isn't there but a date completed is (something that probably shouldn't happen), fall
  -- back to the way tooltips were handled in Blizzard_AchievementUI.xml's MetaCriteriaTemplate:
  elseif ( self.date ) then
    GameTooltip:SetOwner(self, "ANCHOR_RIGHT");
    GameTooltip:AddLine(string.format(ACHIEVEMENT_META_COMPLETED_DATE, self.date), 1, 1, 1);
    checkGuildMembersTooltip(self)
    GameTooltip:Show();
  end
end

local function new_AchievementButton_GetMeta(...)
  local frame = orig_AchievementButton_GetMeta(...)
  frame:SetScript("OnEnter", MetaCriteriaOnEnter)
  return frame;
end


-- TOOLTIP FOR UI'S ACHIEVEMENT BUTTONS
-----------------------------------------

local achbtnOnEnter, achbtnOnLeave, achBtnRedisplay
local AddAchListToTooltip
do
  local button
  local r_sel, g_sel, b_sel = 0.741, 1, 0.467
  local r_com, g_com, b_com = 0.25, 0.75, 0.25
  local r_inc, g_inc, b_inc = 0.6, 0.6, 0.6
  local temptab

  function AddAchListToTooltip(tooltip, list)
    if (type(list) == "table") then
      local _, name, completed, anycomplete
      temptab = temptab or {}
      for i,ach in ipairs(list) do
        _, name, _, completed = GetAchievementInfo(ach)
        if (completed) then
          anycomplete = true
        else
          completed = false  -- nil becomes false for use in temptab.
        end
        temptab[name] = temptab[name] or completed
        -- It being complete takes precedence, since if the name was already used, but this time it's complete,
        -- the previous one must've been for the other faction.
      end
      for name,completed in pairs(temptab) do
        if (completed) then
          tooltip:AddLine(name, r_com, g_com, b_com)
          tooltip:AddTexture("Interface\\RAIDFRAME\\ReadyCheck-Ready");
        else
          tooltip:AddLine(name, 1, 1, 1) --, r_inc, g_inc, b_inc)
          if (anycomplete) then
            tooltip:AddTexture(""); -- fake texture to push the text over
          end
        end
      end
      wipe(temptab)
    else
      local _, name, _, completed = GetAchievementInfo(list)
      if (completed) then
        tooltip:AddLine(name, r_com, g_com, b_com)
        tooltip:AddTexture("Interface\\RAIDFRAME\\ReadyCheck-Ready");
      else
        tooltip:AddLine(name, 1, 1, 1) --, r_inc, g_inc, b_inc)
      end
    end
  end

  function achbtnOnEnter(self)
    local id, tipset, guildtip = self.id, 0
    GameTooltip:SetOwner(self, "ANCHOR_NONE")
    GameTooltip:SetPoint("TOPLEFT", self, "TOPRIGHT", 8, 0)
    GameTooltip:SetBackdropColor(TOOLTIP_DEFAULT_BACKGROUND_COLOR.r, TOOLTIP_DEFAULT_BACKGROUND_COLOR.g, TOOLTIP_DEFAULT_BACKGROUND_COLOR.b)

	-- This section based on part of AchievementShield_OnEnter:
	if ( self.accountWide ) then
		if ( self.completed ) then
			GameTooltip:AddLine(ACCOUNT_WIDE_ACHIEVEMENT_COMPLETED);
		else
			GameTooltip:AddLine(ACCOUNT_WIDE_ACHIEVEMENT);
		end
		tipset = 1
		GameTooltip:Show();
	end
	if ( (tipset == 0 or not self.completed) and self.shield.earnedBy ) then
		GameTooltip:AddLine(format(ACHIEVEMENT_EARNED_BY,self.shield.earnedBy));
		local me = UnitName("player")
		if ( not self.shield.wasEarnedByMe ) then
			GameTooltip:AddLine(format(ACHIEVEMENT_NOT_COMPLETED_BY, me));
		elseif ( me ~= self.shield.earnedBy ) then
			GameTooltip:AddLine(format(ACHIEVEMENT_COMPLETED_BY, me));
		end
		GameTooltip:Show();
		tipset = 1
	end


    checkGuildMembersTooltip(self)

    -- This guild data doesn't pop up as consistently as I'd like but the same thing happens with the default UI and after running tests with the relevant events and functions, it seems to be a Blizzard bug.
    -- Generally, if there's anything to display, selecting the achievement and then moving the cursor away and back will make it work for that achievement. (Same workaround goes for default UI.)

    if (GameTooltip:NumLines() > 0) then  tipset, guildtip = 1, true;  end
    button = self

    if (Overachiever_Settings.UI_SeriesTooltip and (GetNextAchievement(id) or GetPreviousAchievement(id))) then
      if (tipset == 1) then  GameTooltip:AddLine(" ");  end
      tipset = tipset + 1
      GameTooltip:AddLine(L.SERIESTIP)
      GameTooltip:AddLine(" ")
      local ach = GetPreviousAchievement(id)
      local first, _, name, anycomplete
      while (ach) do  -- Find first achievement in the series:
        first = ach
        ach = GetPreviousAchievement(ach)
      end
      ach = first or id
      local completed = select(4, GetAchievementInfo(ach))
      while (ach) do
        _, name = GetAchievementInfo(ach)
        if (ach == id) then
          GameTooltip:AddLine(name, r_sel, g_sel, b_sel)
        elseif (completed) then
          GameTooltip:AddLine(name, r_com, g_com, b_com)
        else
          GameTooltip:AddLine(name, r_inc, g_inc, b_inc)
        end
        if (completed) then
          GameTooltip:AddTexture("Interface\\RAIDFRAME\\ReadyCheck-Ready");
          anycomplete = true
        elseif (anycomplete) then
          GameTooltip:AddTexture(""); -- fake texture to push the text over
        end
        ach, completed = GetNextAchievement(ach)
      end
      GameTooltip:AddLine(" ")
    end

    if (Overachiever_Settings.UI_RequiredForMetaTooltip and AchLookup_metaach[id]) then
      if (tipset == 1) then  GameTooltip:AddLine(" ");  end
      tipset = tipset + 1
      GameTooltip:AddLine(L.REQUIREDFORMETATIP)
      GameTooltip:AddLine(" ")
      AddAchListToTooltip(GameTooltip, AchLookup_metaach[id])
      GameTooltip:AddLine(" ")
    end

    if (Overachiever_Settings.Tooltip_ShowID) then
      if (tipset > 0) then
        if (tipset == 1 and guildtip) then  GameTooltip:AddLine(" ");  end
        GameTooltip:AddDoubleLine(" ", "|cff7eff00ID:|r "..id, nil, nil, nil, 0.741, 1, 0.467)
      else
        GameTooltip:AddLine("|cff7eff00ID:|r "..id, 0.741, 1, 0.467)
      end
      tipset = tipset + 1
    end

    if (tipset > 0) then
      GameTooltip:Show()
      return true
    end
  end

  function achbtnOnLeave(self)
    button = nil
    AchievementMeta_OnLeave(self) -- Used because it sets guildMemberRequestFrame, a variable local to Blizzard_AchievementUI.lua,
    -- to nil without doing anything else except GameTooltip:Hide() which we want to do anyway.
  end

  -- This function is needed to handle cases where OnEnter isn't triggered again because the frame scrolls down
  -- but the cursor remains on the same button:
  function achBtnRedisplay()
    if (button) then
      if (not achbtnOnEnter(button)) then
        GameTooltip:Hide()
      end
    end
  end
end

--local function achbtnShieldOnEnter(self, ...)
--  return achbtnOnEnter(self:GetParent(), ...);
--end


-- GLOBAL FUNCTIONS
-----------------------

function Overachiever.OnEvent(self, event, arg1, ...)
  --chatprint(event)
  if (event == "PLAYER_ENTERING_WORLD") then
    Overachiever.MainFrame:UnregisterEvent("PLAYER_ENTERING_WORLD")
    Overachiever.MainFrame:RegisterEvent("ZONE_CHANGED_NEW_AREA")
    
    BuildCategoryInfo()
    BuildCategoryInfo = nil

    local oldver
    OptionsPanel, oldver = Overachiever.CreateOptions(THIS_TITLE, BuildCriteriaLookupTab_check, AutoTrackCheck_Explore, CheckDraggable_AchFrame)
    Overachiever.CreateOptions = nil

    if (oldver and oldver ~= THIS_VERSION) then
      Overachiever_Settings.Version = THIS_VERSION
      local def, settings = Overachiever.DefaultSettings, Overachiever_Settings
      -- Remove options no longer in this version:
      for k,v in pairs(settings) do
        if (def[k] == nil) then  settings[k] = nil;  end
      end
      -- Add options new to this version, set to default:
      for k,v in pairs(def) do
        if (settings[k] == nil) then  settings[k] = v;  end
      end

      if (tonumber(oldver) < 0.40 and Overachiever_CharVars_Default) then
        Overachiever_CharVars_Default.Pos_AchievementWatchFrame = nil
      end
    end
    
    if (Overachiever_CharVars) then
      oldver = tonumber(Overachiever_CharVars.Version)
      if (oldver < 0.40) then  Overachiever_CharVars.Pos_AchievementWatchFrame = nil;  end
      if (oldver < 0.55) then  Overachiever_CharVars.TrackedAch = nil;  end  -- No longer necessary as between-session objective tracking is now done by WoW itself.

     --[[  No longer necessary as this is now done by WoW itself:
      local tracked = Overachiever_CharVars.TrackedAch
      if (tracked and GetNumTrackedAchievements() == 0) then
      -- Resume tracking from last session:
        if (type(tracked) == "table") then
          for i,id in ipairs(tracked) do
            AddTrackedAchievement(id)
          end
        else
          AddTrackedAchievement(tracked)
        end
      end
     --]]
    else
      Overachiever_CharVars = {}
    end
    Overachiever_CharVars.Version = THIS_VERSION

    AutoTrackCheck_Explore(true)

    GameTooltip:HookScript("OnTooltipSetUnit", Overachiever.ExamineSetUnit)
    GameTooltip:HookScript("OnShow", Overachiever.ExamineOneLiner)
    GameTooltip:HookScript("OnTooltipSetItem", Overachiever.ExamineItem)
    ItemRefTooltip:HookScript("OnTooltipSetItem", Overachiever.ExamineItem)
    hooksecurefunc(ItemRefTooltip, "SetHyperlink", Overachiever.ExamineAchievementTip)
    hooksecurefunc(GameTooltip, "SetHyperlink", Overachiever.ExamineAchievementTip)
    
    local StartTime
    if (Overachiever_Debug) then  StartTime = debugprofilestop();  end
    
    Overachiever.BuildItemLookupTab(THIS_VERSION)
    Overachiever.BuildItemLookupTab = nil

    if (Overachiever_Debug) then
      local prev = StartTime
      StartTime = debugprofilestop()
      chatprint("Building/retrieving food/drink lookup tables took "..(StartTime - prev)/1000 .." seconds.")
    end

    BuildCriteriaLookupTab_check()
    if (Overachiever_Debug) then
      chatprint("Building other criteria lookup tables took "..(debugprofilestop() - StartTime)/1000 .." seconds.")
    end

  elseif (event == "ZONE_CHANGED_NEW_AREA") then
    AutoTrackCheck_Explore()

  elseif (event == "TRACKED_ACHIEVEMENT_UPDATE") then
    if (arg1 and arg1 > 0) then  -- Attempt to work around an apparent WoW bug. May prevent errors but if the given ID is 0, we have no way of knowing what the achievement really was so we can't track it (unless there's another call with the correct data).
      local criteriaID, elapsed, duration = ...
      if (duration and elapsed < duration) then
        Overachiever.RecentReminders[arg1] = time()
        if (Overachiever_Settings.Tracker_AutoTimer and
            not setTracking(arg1) and AutoTrackedAch_explore and IsTrackedAchievement(AutoTrackedAch_explore)) then
          -- If failed to track this, remove an exploration achievement that was auto-tracked and try again:
          RemoveTrackedAchievement(AutoTrackedAch_explore)
          if (not setTracking(arg1)) then
            -- If still didn't successfully track new achievement, track previous achievement again:
            AddTrackedAchievement(AutoTrackedAch_explore)
          end
        end
      end
	end

  elseif (event == "ADDON_LOADED" and arg1 == "Blizzard_AchievementUI") then
    Overachiever.MainFrame:UnregisterEvent("ADDON_LOADED")
    -- Meta-criterea creation intercept:
    orig_AchievementButton_GetMeta = AchievementButton_GetMeta
    AchievementButton_GetMeta = new_AchievementButton_GetMeta
    -- Add "series" tooltip to default achievement buttons:
    Overachiever.UI_HookAchButtons(AchievementFrameAchievementsContainer.buttons, AchievementFrameAchievementsContainerScrollBar)
    -- Allow closing frame with Escape even when UIPanelLayout-enabled is set to false:
    tinsert(UISpecialFrames, "AchievementFrame");

    -- Make main achievement UI draggable:
    -- - Prevent UIParent.lua from seeing area field (or it'll do things that mess up making the frame draggable).
    if (UIPanelWindows["AchievementFrame"]) then  -- This if statement prevents error messages when the addon MoveAnything is used to move AchievementFrame.
      orig_AchievementFrame_area = UIPanelWindows["AchievementFrame"].area
      UIPanelWindows["AchievementFrame"].area = nil
    end
    -- - Hook the first OnShow call to complete this. (Not done now in case saved variables aren't ready or the frame
    --   isn't showing right away.)
    orig_AchievementFrame_OnShow = AchievementFrame:GetScript("OnShow")
    AchievementFrame:SetScript("OnShow", AchievementUI_FirstShown)
    --[[ Pre-3.1 method:
    orig_AchievementFrame_OnShow = AchievementFrame_OnShow
    AchievementFrame_OnShow = AchievementUI_FirstShown
    --]]

  elseif (event == "PLAYER_LOGOUT") then
    if (Overachiever_CharVars.Pos_AchievementFrame) then
    -- Set standard location for this frame for other characters that don't have positions saved yet:
      Overachiever_CharVars_Default = Overachiever_CharVars_Default or {}
      Overachiever_CharVars_Default.Pos_AchievementFrame = Overachiever_CharVars.Pos_AchievementFrame
    end
   --[[  No longer necessary as this is now done by WoW itself:
    -- Remember tracked achievements:
    local num = GetNumTrackedAchievements()
    if (num > 0) then
      if (num == 1) then
        Overachiever_CharVars.TrackedAch = GetTrackedAchievements()
      else
        Overachiever_CharVars.TrackedAch = { GetTrackedAchievements() }
      end
    else
      Overachiever_CharVars.TrackedAch = nil
    end
   --]]

  end
end

function Overachiever.SearchForAchievement(isCustomList, searchList, argnum, msg, toChat, givelist, retTable)
-- If isCustomList is false (or nil), searchList should either be nil or an array of achievement category ID numbers.
-- If isCustomList is true, searchList should be an array of achievement ID numbers.
-- If isCustomList is 2, searchList should be a table containing such arrays.
  if (not searchList) then  isCustomList = nil;  end
  if (not givelist and not toChat) then
    if (isCustomList) then
      if (isCustomList == 2) then
        local id
        for k,sublist in pairs(searchList) do
          id = getAchievementID_tab(sublist, argnum, msg, true)
          if (id) then  return id;  end
        end
        return;
      else
        return getAchievementID_tab(searchList, argnum, msg, true)
      end
    else
      return getAchievementID(searchList, argnum, msg, true)
    end
  end
  local tab
  if (isCustomList) then
    if (isCustomList == 2) then
      tab = SearchAchievements_tab(searchList, argnum, msg, true)
    else
      tab = getAchievementID_tab(searchList, argnum, msg, true, true)
    end
  else
    tab = SearchAchievements(searchList, argnum, msg, true)
  end
  if (tab) then
    local id = tab[1]
    if (toChat) then  chatprint(L.MSG_OPENINGTO..GetAchievementLink(id));  end
    local tab2
    if (givelist) then
      tab2 = type(retTable) == "table" and wipe(retTable) or {}
      copytab(tab, tab2)
      if (not toChat) then  return tab2;  end
    end
    local size = #(tab)
    if (size == 2) then
      chatprint(L.MSG_ONEFOUND..GetAchievementLink(tab[2]))
    elseif (size > 2) then
      chatprint(L.MSG_NUMFOUNDLIST:format(size-1))
      local a, b, c
      for i=2,size,3 do
        a, b, c = tab[i], tab[i+1], tab[i+2]
        a, b, c = GetAchievementLink(a), b and GetAchievementLink(b), c and GetAchievementLink(c)
        if (b) then  a = a.."  --  "..b;  end
        if (c) then  a = a.."  --  "..c;  end
        chatprint(a, "-- ")
      end
    end
    return tab2 or id
  elseif (toChat) then
    chatprint(L.MSG_NAMENOTFOUND:format(msg))
  end
end

function Overachiever.OpenTab(name)
  if (not AchievementFrame or not AchievementFrame:IsShown()) then
    ToggleAchievementFrame()
  end
  local frame = _G[name]
  if (frame) then  Overachiever.OpenTab_frame(frame);  end
end

function Overachiever.UI_SelectAchievement(id, failFunc, ...)
  AchievementFrameBaseTab_OnClick(1)
  Overachiever.NoAlterSetFilter = true
  local retOK, ret1 = pcall(AchievementFrame_SelectAchievement, id)
  Overachiever.NoAlterSetFilter = nil
  if (retOK) then
    local category = GetAchievementCategory(id)
    local _, parentID = GetCategoryInfo(category)
    if (parentID == -1) then
      expandCategory(category)
    end
  else
    chatprint(L.MSG_ACHNOTFOUND)
    if (Overachiever_Debug) then
      chatprint(ret1, "[Error]")
    elseif (failFunc) then
      failFunc(...)
    else
    -- Open to summary to hide potentially problematic (though interesting) listing of irregular achievements:
      AchievementCategoryButton_OnClick(AchievementFrameCategoriesContainerButton1)
    end
  end
end

function Overachiever.UI_HookAchButtons(buttons, scrollbar)
  for i,button in ipairs(buttons) do
    button:HookScript("OnEnter", achbtnOnEnter)
    button:HookScript("OnLeave", achbtnOnLeave)
    local shield = _G[button:GetName().."Shield"]
    --shield:SetScript("OnEnter", achbtnShieldOnEnter)
    shield:EnableMouse(false) -- Removes its tie to AchievementShield_OnEnter and lets the parent button control highlighting, etc.
  end
  scrollbar:HookScript("OnValueChanged", achBtnRedisplay)
end

function Overachiever.UI_GetValidCategories(sel)
  if (not CATEGORIES_ALL) then
    CATEGORIES_INDIV_ALL = GetCategoryList()
    CATEGORIES_GUILD_ALL = GetGuildCategoryList()
    CATEGORIES_ALL = {}
    copytab(CATEGORIES_INDIV_ALL, CATEGORIES_ALL)
    local i = #CATEGORIES_ALL
    for k,v in pairs(CATEGORIES_GUILD_ALL) do
      i = i + 1
      CATEGORIES_ALL[i] = v
    end
  end
  return sel == 1 and CATEGORIES_INDIV_ALL or sel == 2 and CATEGORIES_GUILD_ALL or CATEGORIES_ALL
end

Overachiever.IsAchievementInUI = isAchievementInUI;
Overachiever.OpenToAchievement = openToAchievement;
Overachiever.GetAllAchievements = getAllAchievements;
Overachiever.BuildCriteriaLookupTab = BuildCriteriaLookupTab;
Overachiever.AddAchListToTooltip = AddAchListToTooltip;
Overachiever.IsGuildAchievement = isGuildAchievement
Overachiever.isUIInGuildView = isUIInGuildView


-- SLASH COMMANDS
-------------------

local function slashHandler(msg, self, silent, func_nomsg)
  if (msg == "") then
    func_nomsg = func_nomsg or ToggleAchievementFrame
    func_nomsg();
  elseif (msg == "!!rebuild") then
    Overachiever_CharVars_Consumed.LastBuilt = nil
    chatprint("Food/drink lookup table will be rebuilt the next time Overachiever loads. Use the /reload command to do so now.")
  else
    if (strsub(msg, 1,1) == "#") then
      local id = tonumber(strsub(msg, 2))
      if (id) then
        if (GetAchievementInfo(id)) then
          if (not silent) then  chatprint(L.MSG_OPENINGTO..GetAchievementLink(id));  end
          openToAchievement(id)
        elseif (not silent) then
          chatprint(L.MSG_INVALIDID);
        end
        return;
      end
    end
    local id = Overachiever.SearchForAchievement(nil, nil, ACHINFO_NAME, msg, not silent)
    if (id) then  openToAchievement(id);  end
  end
end

local function openOptions()
  InterfaceOptionsFrame_OpenToCategory(OptionsPanel)
  -- Working around a Blizzard bug by calling this twice:
  InterfaceOptionsFrame_OpenToCategory(OptionsPanel)
end

SLASH_Overachiever1 = "/oa";
SlashCmdList["Overachiever"] = function (msg, self)  slashHandler(msg, self, nil, openOptions);  end

SLASH_Overachiever_silent1 = "/oasilent";
SLASH_Overachiever_silent2 = "/oas";
SlashCmdList["Overachiever_silent"] = function(msg, self)  slashHandler(msg, self, true, openOptions);  end;

SLASH_Overachiever_silentAch1 = "/achsilent";
SLASH_Overachiever_silentAch2 = "/achs";
SlashCmdList["Overachiever_silentAch"] = function(msg, self)  slashHandler(msg, self, true);  end;

-- Replace the original slash command handler for /ach, /achieve, /achievement, and /achievements:
SlashCmdList["ACHIEVEMENTUI"] = slashHandler;


-- LOCALIZATION ASSIST
--------------------------

function Overachiever.GetMapContinents_names()
  local tab = {}
  local continents = { GetMapContinents() }
  local count = 0
  for i,v in ipairs(continents) do
    if (i % 2 == 0) then -- As of WoW 6.0, only the even numbered results are strings. The rest are integers (IDs for the continents).
      count = count + 1
      tab[count] = continents[i];
    end
  end
  return unpack(tab)
end

function Overachiever.GetMapZones_names(index)
  local tab = {}
  local zones = { GetMapZones(index) }
  local count = 0
  for i,v in ipairs(zones) do
    if (i % 2 == 0) then -- As of WoW 6.0, only the even numbered results are strings. The rest are integers (IDs for the continents).
      count = count + 1
      tab[count] = zones[i];
    end
  end
  return unpack(tab)
end


if (Overachiever_Debug) then

  function Overachiever.Debug_GetKillCriteriaAchs()
    if (not Overachiever.AchLookup_kill) then  return;  end
    local tab, _, a = {}
    for k,v in pairs(Overachiever.AchLookup_kill) do
      for i = 1, #v, 2 do
        _, a = GetAchievementInfo( v[i] )
        tab[a] = (tab[a] or 0) + 1
      end
    end
    return tab
  end

  -- Achievement and criteria data gathering:

  function Overachiever.Debug_GetAchData()
    local tab = Overachiever_Settings.Debug_AchData
    if (not tab) then  Overachiever_Settings.Debug_AchData = {};  tab = Overachiever_Settings.Debug_AchData;  end
    local _, Name, Points, Completed, Month, Day, Year, Description, Flags, Image, RewardText
    local critString, critType, completed, quantity, reqQuantity, charName, flags, assetID, quantityString, critID
    for k,id in pairs(OVERACHIEVER_ACHID) do
      _, Name, Points, Completed, Month, Day, Year, Description, Flags, Image, RewardText = GetAchievementInfo(id)
      tab[id] = { Name = Name, Description = Description, RewardText = RewardText }
      tab[id].Criteria = {}
      local crit = tab[id].Criteria
      for i=1,GetAchievementNumCriteria(id) do
        critString, critType, completed, quantity, reqQuantity, charName, flags, assetID, quantityString, critID = GetAchievementCriteriaInfo(id, i)
        if (not strfind(quantityString, "/")) then  quantityString = nil;  end
        crit[i] = { critString = critString, quantityString = quantityString }
      end
    end
    chatprint("Achievement/criteria data gathered. Reload the interface or log out to output to saved variables file.")
  end

  -- Zone data gathering:

  local ZoneID

  local function BuildZoneIDTable_z(connum, num, zonename, next, ...)
    num = num + 1
    ZoneID[zonename] = {}
    ZoneID[zonename].C = connum
    ZoneID[zonename].Z = num
    if (next) then
      BuildZoneIDTable_z(connum, num, next, ...)
    end
  end

  -- Intended first call: BuildZoneIDTable(0, Overachiever.GetMapContinents_names());
  local function BuildZoneIDTable(num, conname, next, ...)
    num = num + 1
    --print("BuildZoneIDTable: "..conname.." ("..num..")")
    BuildZoneIDTable_z(num, 0, Overachiever.GetMapZones_names(num))
    if (next) then
      BuildZoneIDTable(num, next, ...)
    end
  end

  -- /run Overachiever.Debug_GetExplorationData(true)
  function Overachiever.Debug_GetExplorationData(testAchMatch, saveZoneIDs)
    if (not ZoneID and (testAchMatch or saveZoneIDs)) then
      ZoneID = {}
      BuildZoneIDTable(0, Overachiever.GetMapContinents_names());
      chatprint("Zone data gathered.")
    end
    if (saveZoneIDs) then  Overachiever_Settings.Debug_ZoneData = ZoneID;  end

    local tab = {}
    local catname, id, name, trimname
    for _, category in ipairs(CATEGORIES_EXPLOREZONES) do
      catname = GetCategoryInfo(category)
      tab[catname] = {}
      for i=1,GetCategoryNumAchievements(category) do
        id, name = GetAchievementInfo(category, i)
        if (id) then
          if (testAchMatch) then
            trimname = strsub(name,9) -- Cut off "Explore " - meant for use with English client only
            if (trimname and ZoneID[trimname]) then
              name = trimname
            else
              chatprint("Achievement name doesn't match a zone: "..name)
              name = "!! "..name
            end
          end
          tab[catname][name] = id;
        end
      end
    end
    Overachiever_Settings.Debug_ExplorationData = tab
    chatprint("Exploration Achievement data gathered. Reload the interface or log out to output to saved variables file.")
  end

end


-- FRAME INITIALIZATION
--------------------------

Overachiever.MainFrame = CreateFrame("Frame")
Overachiever.MainFrame:Hide()
Overachiever.MainFrame:RegisterEvent("PLAYER_ENTERING_WORLD")
Overachiever.MainFrame:RegisterEvent("ADDON_LOADED")
--Overachiever.MainFrame:RegisterEvent("ACHIEVEMENT_EARNED")
Overachiever.MainFrame:RegisterEvent("TRACKED_ACHIEVEMENT_UPDATE")
Overachiever.MainFrame:RegisterEvent("PLAYER_LOGOUT")

Overachiever.MainFrame:SetScript("OnEvent", Overachiever.OnEvent)
Overachiever.MainFrame:SetScript("OnUpdate", AchievementUI_FirstShown_post)
