-----------------------------------------------------------------------
-- Upvalued Lua API.
-----------------------------------------------------------------------
local _G = getfenv(0)

local pairs = _G.pairs
local tonumber = _G.tonumber

local bit = _G.bit
local math = _G.math
local table = _G.table


-----------------------------------------------------------------------
-- AddOn namespace.
-----------------------------------------------------------------------
local ADDON_NAME, private = ...

local LibStub = _G.LibStub
local WDP = LibStub("AceAddon-3.0"):NewAddon(ADDON_NAME, "AceEvent-3.0", "AceTimer-3.0")

local DatamineTT = _G.CreateFrame("GameTooltip", "WDPDatamineTT", _G.UIParent, "GameTooltipTemplate")
DatamineTT:SetOwner(_G.WorldFrame, "ANCHOR_NONE")


-----------------------------------------------------------------------
-- Local constants.
-----------------------------------------------------------------------
local DATABASE_DEFAULTS = {
    global = {
        items = {},
        npcs = {},
        objects = {},
        quests = {},
        zones = {},
    }
}


local EVENT_MAPPING = {
    COMBAT_LOG_EVENT_UNFILTERED = true,
    COMBAT_TEXT_UPDATE = true,
    LOOT_OPENED = true,
    MERCHANT_SHOW = "UpdateMerchantItems",
    MERCHANT_UPDATE = "UpdateMerchantItems",
    PET_BAR_UPDATE = true,
    PLAYER_TARGET_CHANGED = true,
    QUEST_COMPLETE = true,
    QUEST_DETAIL = true,
    QUEST_LOG_UPDATE = true,
    TRAINER_SHOW = true,
    UNIT_QUEST_LOG_CHANGED = true,
    UNIT_SPELLCAST_FAILED = "HandleSpellFailure",
    UNIT_SPELLCAST_FAILED_QUIET = "HandleSpellFailure",
    UNIT_SPELLCAST_INTERRUPTED = "HandleSpellFailure",
    UNIT_SPELLCAST_SENT = true,
    UNIT_SPELLCAST_SUCCEEDED = true,
}


local AF = private.ACTION_TYPE_FLAGS


local PLAYER_CLASS = _G.select(2, _G.UnitClass("player"))


-----------------------------------------------------------------------
-- Local variables.
-----------------------------------------------------------------------
local db
local durability_timer_handle
local target_location_timer_handle
local action_data = {}
local faction_names = {}


-----------------------------------------------------------------------
-- Helper Functions.
-----------------------------------------------------------------------
local function DBEntry(data_type, unit_id)
    if not data_type or not unit_id then
        return
    end
    local unit = db[data_type][unit_id]

    if not unit then
        db[data_type][unit_id] = {}
        unit = db[data_type][unit_id]
    end
    return unit
end


local function InstanceDifficultyToken()
    local _, instance_type, instance_difficulty, difficulty_name, _, _, is_dynamic = _G.GetInstanceInfo()
    if difficulty_name == "" then
        difficulty_name = "NONE"
    end
    return ("%s:%s:%s"):format(instance_type:upper(), difficulty_name:upper():gsub(" ", "_"), _G.tostring(is_dynamic))
end


local function CurrentLocationData()
    local map_level = _G.GetCurrentMapDungeonLevel() or 0
    local x, y = _G.GetPlayerMapPosition("player")

    x = x or 0
    y = y or 0

    if x == 0 and y == 0 then
        for level_index = 1, _G.GetNumDungeonMapLevels() do
            _G.SetDungeonMapLevel(level_index)
            x, y = _G.GetPlayerMapPosition("player")

            if x and y and (x > 0 or y > 0) then
                _G.SetDungeonMapLevel(map_level)
                map_level = level_index
                break
            end
        end
    end

    if _G.DungeonUsesTerrainMap() then
        map_level = map_level - 1
    end
    return _G.GetRealZoneText(), _G.GetCurrentMapAreaID(), ("%.2f"):format(x * 100), ("%.2f"):format(y * 100), map_level, InstanceDifficultyToken()
end


local function ItemLinkToID(item_link)
    if not item_link then
        return
    end
    return tonumber(item_link:match("item:(%d+)"))
end


do
    local UNIT_TYPE_BITMASK = 0x007

    function WDP:ParseGUID(guid)
        if not guid then
            return
        end
        local types = private.UNIT_TYPES
        local unit_type = _G.bit.band(tonumber(guid:sub(1, 5)), UNIT_TYPE_BITMASK)

        if unit_type ~= types.PLAYER and unit_type ~= types.PET then
            return unit_type, tonumber(guid:sub(-12, -9), 16)
        end

        return unit_type
    end
end -- do-block


local function UpdateObjectLocation(identifier)
    if not identifier then
        return
    end
    local zone_name, area_id, x, y, map_level, instance_token = CurrentLocationData()
    local object = DBEntry("objects", identifier)
    object.locations = object.locations or {}

    local location_token = ("%s:%d"):format(zone_name, area_id)

    if not object.locations[location_token] then
        object.locations[location_token] = {}
    end
    object.locations[location_token][("%s:%s:%s:%s"):format(instance_token, map_level, x, y)] = true
end


local function HandleItemUse(item_link, bag_index, slot_index)
    if not item_link then
        return
    end
    local item_id = ItemLinkToID(item_link)

    if not bag_index or not slot_index then
        for new_bag_index = 0, _G.NUM_BAG_FRAMES do
            for new_slot_index = 1, _G.GetContainerNumSlots(new_bag_index) do
                if item_id == ItemLinkToID(_G.GetContainerItemLink(new_bag_index, new_slot_index)) then
                    bag_index = new_bag_index
                    slot_index = new_slot_index
                    break
                end
            end
        end
    end

    if not bag_index or not slot_index then
        return
    end
    local _, _, _, _, _, is_lootable = _G.GetContainerItemInfo(bag_index, slot_index)

    if not is_lootable then
        return
    end
    DatamineTT:ClearLines()
    DatamineTT:SetBagItem(bag_index, slot_index)

    for line_index = 1, DatamineTT:NumLines() do
        local current_line = _G["WDPDatamineTTTextLeft" .. line_index]

        if not current_line then
            break
        end

        if current_line:GetText() == _G.ITEM_OPENABLE then
            table.wipe(action_data)
            action_data.type = AF.ITEM
            action_data.item_id = item_id
            action_data.label = "contains"
            break
        end
    end
end


local function UpdateFactionNames()
    for faction_index = 1, 1000 do
        local faction_name, _, _, _, _, _, _, _, is_header = _G.GetFactionInfo(faction_index)

        if faction_name and not is_header then
            faction_names[faction_name] = true
        elseif not faction_name then
            break
        end
    end
end


-----------------------------------------------------------------------
-- Methods.
-----------------------------------------------------------------------
function WDP:OnInitialize()
    db = LibStub("AceDB-3.0"):New("WoWDBProfilerData", DATABASE_DEFAULTS, "Default").global

    local raw_db = _G["WoWDBProfilerData"]

    local build_num = tonumber(private.build_num)

    if raw_db.build_num and raw_db.build_num < build_num then
        for entry in pairs(DATABASE_DEFAULTS.global) do
            db[entry] = {}
        end
        raw_db.build_num = build_num
    elseif not raw_db.build_num then
        raw_db.build_num = build_num
    end
end


function WDP:OnEnable()
    for event_name, mapping in pairs(EVENT_MAPPING) do
        self:RegisterEvent(event_name, (_G.type(mapping) ~= "boolean") and mapping or nil)
    end
    durability_timer_handle = self:ScheduleRepeatingTimer("ProcessDurability", 30)
    target_location_timer_handle = self:ScheduleRepeatingTimer("UpdateTargetLocation", 0.2)

    _G.hooksecurefunc("UseContainerItem", function(bag_index, slot_index, target_unit)
        if target_unit then
            return
        end
        HandleItemUse(_G.GetContainerItemLink(bag_index, slot_index), bag_index, slot_index)
    end)

    _G.hooksecurefunc("UseItemByName", function(identifier, target_unit)
        if target_unit then
            return
        end
        local _, item_link = _G.GetItemInfo(identifier)
        HandleItemUse(item_link)
    end)
end


local function RecordDurability(item_id, durability)
    if not durability or durability <= 0 then
        return
    end

    if not db.items[item_id] then
        db.items[item_id] = {}
    end
    db.items[item_id].durability = durability
end


function WDP:ProcessDurability()
    for slot_index = 0, _G.INVSLOT_LAST_EQUIPPED do
        local item_id = _G.GetInventoryItemID("player", slot_index)

        if item_id and item_id > 0 then
            local _, max_durability = _G.GetInventoryItemDurability(slot_index)
            RecordDurability(item_id, max_durability)
        end
    end

    for bag_index = 0, _G.NUM_BAG_SLOTS do
        for slot_index = 1, _G.GetContainerNumSlots(bag_index) do
            local item_id = _G.GetContainerItemID(bag_index, slot_index)

            if item_id and item_id > 0 then
                local _, max_durability = _G.GetContainerItemDurability(bag_index, slot_index)
                RecordDurability(item_id, max_durability)
            end
        end
    end
end


function WDP:UpdateTargetLocation()
    local is_dead = _G.UnitIsDead("target")

    if not _G.UnitExists("target") or _G.UnitPlayerControlled("target") or (_G.UnitIsTapped("target") and not is_dead) then
        return
    end

    for index = 1, 4 do
        if not _G.CheckInteractDistance("target", index) then
            return
        end
    end
    local target_guid = _G.UnitGUID("target")
    local unit_type, unit_idnum = self:ParseGUID(target_guid)

    if unit_type ~= private.UNIT_TYPES.NPC or not unit_idnum then
        return
    end
    local zone_name, area_id, x, y, map_level, instance_token = CurrentLocationData()
    local npc_data = DBEntry("npcs", unit_idnum).encounter_data[("level_%d"):format(_G.UnitLevel("target"))]
    npc_data.locations = npc_data.locations or {}

    local location_token = ("%s:%d"):format(zone_name, area_id)

    if not npc_data.locations[location_token] then
        npc_data.locations[location_token] = {}
    end

    -- Only record corpse location if there is no entry for this GUID.
    if is_dead and npc_data.locations[location_token][target_guid] then
        return
    end
    npc_data.locations[location_token][target_guid] = ("%s:%s:%s:%s"):format(instance_token, map_level, x, y)
end


-----------------------------------------------------------------------
-- Event handlers.
-----------------------------------------------------------------------
do
    local EXTRACT_GAS_SPELL_ID = 30427
    local FLAGS_NPC = bit.bor(_G.COMBATLOG_OBJECT_TYPE_GUARDIAN, _G.COMBATLOG_OBJECT_CONTROL_NPC)
    local FLAGS_NPC_CONTROL = bit.bor(_G.COMBATLOG_OBJECT_AFFILIATION_OUTSIDER, _G.COMBATLOG_OBJECT_CONTROL_NPC)


    local function RecordNPCSpell(sub_event, source_guid, source_name, source_flags, dest_guid, dest_name, dest_flags, spell_id, spell_name)
        if not spell_id then
            return
        end
        local source_type, source_id = WDP:ParseGUID(source_guid)

        if not source_id or source_type ~= private.UNIT_TYPES.NPC then
            return
        end

        if bit.band(FLAGS_NPC_CONTROL, source_flags) == FLAGS_NPC_CONTROL and bit.band(FLAGS_NPC, source_flags) ~= 0 then
            local npc = DBEntry("npcs", source_id)
            local instance_token = InstanceDifficultyToken()
            npc.spells = npc.spells or {}
            npc.spells[instance_token] = npc.spells[instance_token] or {}
            npc.spells[instance_token][spell_id] = true
        end
    end


    local COMBAT_LOG_FUNCS = {
        SPELL_AURA_APPLIED = RecordNPCSpell,
        SPELL_CAST_START = RecordNPCSpell,
        SPELL_CAST_SUCCESS = RecordNPCSpell,
        UNIT_DISSIPATES = function(sub_event, source_guid, source_name, source_flags, dest_guid, dest_name, dest_flags)
        -- TODO: Write this.
        end,
    }


    function WDP:COMBAT_LOG_EVENT_UNFILTERED(event, time_stamp, sub_event, hide_caster, source_guid, source_name, source_flags, source_raid_flags, dest_guid, dest_name, dest_flags, dest_raid_flags, ...)
        local combat_log_func = COMBAT_LOG_FUNCS[sub_event]

        if not combat_log_func then
            return
        end
        combat_log_func(sub_event, source_guid, source_name, source_flags, dest_guid, dest_name, dest_flags, ...)
    end
end -- do-block


function WDP:COMBAT_TEXT_UPDATE(event, message_type, faction_name, amount)
    local npc = DBEntry("npcs", action_data.identifier)

    if not npc then
        return
    end
    npc.encounter_data[action_data.npc_level].reputations = npc.encounter_data[action_data.npc_level].reputations or {}
    npc.encounter_data[action_data.npc_level].reputations[faction_name] = amount
end


do
    local re_gold = _G.GOLD_AMOUNT:gsub("%%d", "(%%d+)")
    local re_silver = _G.SILVER_AMOUNT:gsub("%%d", "(%%d+)")
    local re_copper = _G.COPPER_AMOUNT:gsub("%%d", "(%%d+)")


    local function _moneyMatch(money, re)
        return money:match(re) or 0
    end


    local function _toCopper(money)
        if not money then
            return 0
        end

        return _moneyMatch(money, re_gold) * 10000 + _moneyMatch(money, re_silver) * 100 + _moneyMatch(money, re_copper)
    end


    local LOOT_VERIFY_FUNCS = {
        [AF.ITEM] = function()
            local locked_item_id

            for bag_index = 0, _G.NUM_BAG_FRAMES do
                for slot_index = 1, _G.GetContainerNumSlots(bag_index) do
                    local _, _, is_locked = _G.GetContainerItemInfo(bag_index, slot_index)

                    if is_locked then
                        locked_item_id = ItemLinkToID(_G.GetContainerItemLink(bag_index, slot_index))
                    end
                end
            end

            if not locked_item_id or (action_data.item_id and action_data.item_id ~= locked_item_id) then
                return false
            end
            action_data.item_id = locked_item_id
            return true
        end,
        [AF.NPC] = function()
            if not _G.UnitExists("target") or _G.UnitIsFriend("player", "target") or _G.UnitIsPlayer("target") or _G.UnitPlayerControlled("target") then
                return false
            end
            local unit_type, id_num = WDP:ParseGUID(_G.UnitGUID("target"))
            action_data.identifier = id_num
            return true
        end,
        [AF.OBJECT] = true,
        [AF.ZONE] = function()
            return action_data.label and _G.IsFishingLoot()
        end,
    }


    local function GenericLootUpdate(data_type)
        local entry = DBEntry(data_type, action_data.identifier)

        print("GenericLootUpdate")
        if not entry then
            print(("Missing DB entry for %s (%s)"):format(data_type, tostring(action_data.identifier)))
            return
        end
        local loot_type = action_data.label or "drops"
        entry[loot_type] = entry[loot_type] or {}

        for index = 1, #action_data.loot_list do
            table.insert(entry[loot_type], action_data.loot_list[index])
        end
    end


    local LOOT_UPDATE_FUNCS = {
        [AF.ITEM] = function()
            local item = DBEntry("items", action_data.item_id)
            local loot_type = action_data.label or "drops"
            item[loot_type] = item[loot_type] or {}

            for index = 1, #action_data.loot_list do
                table.insert(item[loot_type], action_data.loot_list[index])
            end
        end,
        [AF.NPC] = function()
            GenericLootUpdate("npcs")
        end,
        [AF.OBJECT] = function()
            GenericLootUpdate("objects")
        end,
        [AF.ZONE] = function()
            local loot_type = action_data.label or "drops"
            local zone = DBEntry("zones", action_data.zone)
            zone[loot_type] = zone[loot_type] or {}

            local location_data = ("%s:%s:%s:%s"):format(action_data.instance_token, action_data.map_level, action_data.x, action_data.y)
            local loot_data = zone[loot_type][location_data]

            if not loot_data then
                zone[loot_type][location_data] = {}
                loot_data = zone[loot_type][location_data]
            end

            for index = 1, #action_data.loot_list do
                table.insert(loot_data, action_data.loot_list[index])
            end
        end,
    }


    function WDP:LOOT_OPENED()
        if action_data.looting then
            return
        end

        if not action_data.type then
            action_data.type = AF.NPC
        end
        local verify_func = LOOT_VERIFY_FUNCS[action_data.type]
        local update_func = LOOT_UPDATE_FUNCS[action_data.type]

        if not verify_func or not update_func then
            return
        end

        if _G.type(verify_func) == "function" and not verify_func() then
            return
        end
        -- TODO: Remove this check once the MoP client goes live
        local wow_version = private.wow_version
        local loot_registry = {}
        action_data.loot_list = {}
        action_data.looting = true

        if wow_version == "5.0.1" then
            for loot_slot = 1, _G.GetNumLootItems() do
                local icon_texture, item_text, quantity, quality, locked = _G.GetLootSlotInfo(loot_slot)

                local slot_type = _G.GetLootSlotType(loot_slot)

                if slot_type == _G.LOOT_SLOT_ITEM then
                    local item_id = ItemLinkToID(_G.GetLootSlotLink(loot_slot))
                    loot_registry[item_id] = (loot_registry[item_id]) or 0 + quantity
                elseif slot_type == _G.LOOT_SLOT_MONEY then
                    table.insert(action_data.loot_list, ("money:%d"):format(_toCopper(item_text)))
                elseif slot_type == _G.LOOT_SLOT_CURRENCY then
                    table.insert(action_data.loot_list, ("currency:%d:%s"):format(quantity, icon_texture:match("[^\\]+$"):lower()))
                end
            end
        else
            for loot_slot = 1, _G.GetNumLootItems() do
                local icon_texture, item_text, quantity, quality, locked = _G.GetLootSlotInfo(loot_slot)
                if _G.LootSlotIsItem(loot_slot) then
                    local item_id = ItemLinkToID(_G.GetLootSlotLink(loot_slot))
                    loot_registry[item_id] = (loot_registry[item_id]) or 0 + quantity
                elseif _G.LootSlotIsCoin(loot_slot) then
                    table.insert(action_data.loot_list, ("money:%d"):format(_toCopper(item_text)))
                elseif _G.LootSlotIsCurrency(loot_slot) then
                    table.insert(action_data.loot_list, ("currency:%d:%s"):format(quantity, icon_texture:match("[^\\]+$"):lower()))
                end
            end
        end

        for item_id, quantity in pairs(loot_registry) do
            table.insert(action_data.loot_list, ("%d:%d"):format(item_id, quantity))
        end
        update_func()
    end
end -- do-block


local POINT_MATCH_PATTERNS = {
    ("^%s$"):format(_G.ITEM_REQ_ARENA_RATING:gsub("%%d", "(%%d+)")), -- May no longer be necessary
    ("^%s$"):format(_G.ITEM_REQ_ARENA_RATING_3V3:gsub("%%d", "(%%d+)")), -- May no longer be necessary
    ("^%s$"):format(_G.ITEM_REQ_ARENA_RATING_5V5:gsub("%%d", "(%%d+)")), -- May no longer be necessary
    ("^%s$"):format(_G.ITEM_REQ_ARENA_RATING_BG:gsub("%%d", "(%%d+)")),
    ("^%s$"):format(_G.ITEM_REQ_ARENA_RATING_3V3_BG:gsub("%%d", "(%%d+)")),
}


function WDP:UpdateMerchantItems()
    local unit_type, unit_idnum = self:ParseGUID(_G.UnitGUID("target"))

    if unit_type ~= private.UNIT_TYPES.NPC or not unit_idnum then
        return
    end
    local merchant = DBEntry("npcs", unit_idnum)
    merchant.sells = merchant.sells or {}

    for item_index = 1, _G.GetMerchantNumItems() do
        local _, _, copper_price, stack_size, num_available, _, extended_cost = _G.GetMerchantItemInfo(item_index)
        local item_id = ItemLinkToID(_G.GetMerchantItemLink(item_index))

        if item_id and item_id > 0 then
            local price_string = copper_price

            if extended_cost then
                local bg_points = 0
                local personal_points = 0

                DatamineTT:ClearLines()
                DatamineTT:SetMerchantItem(item_index)

                for line_index = 1, DatamineTT:NumLines() do
                    local current_line = _G["WDPDatamineTTTextLeft" .. line_index]

                    if not current_line then
                        break
                    end
                    local breakout

                    for match_index = 1, #POINT_MATCH_PATTERNS do
                        local match1, match2 = current_line:GetText():match(POINT_MATCH_PATTERNS[match_index])
                        personal_points = personal_points + (match1 or 0)
                        bg_points = bg_points + (match2 or 0)

                        if match1 or match2 then
                            breakout = true
                            break
                        end
                    end

                    if breakout then
                        break
                    end
                end
                local currency_list = {}

                price_string = ("%s:%s:%s"):format(price_string, bg_points, personal_points)

                for cost_index = 1, _G.GetMerchantItemCostInfo(item_index) do
                    local icon_texture, amount_required, currency_link = _G.GetMerchantItemCostItem(item_index, cost_index)
                    local currency_id = currency_link and ItemLinkToID(currency_link) or nil

                    if not currency_id or currency_id < 1 then
                        if not icon_texture then
                            return
                        end
                        currency_id = icon_texture:match("[^\\]+$"):lower()
                    end
                    currency_list[#currency_list + 1] = ("(%s:%s)"):format(amount_required, currency_id)
                end

                for currency_index = 1, #currency_list do
                    price_string = ("%s:%s"):format(price_string, currency_list[currency_index])
                end
            end
            merchant.sells[("%s:%s:[%s]"):format(item_id, stack_size, price_string)] = num_available
        end
    end

    if _G.CanMerchantRepair() then
        merchant.can_repair = true
    end
end


function WDP:PET_BAR_UPDATE()
    if not action_data.label or not action_data.label == "mind_control" then
        return
    end
    local unit_type, unit_idnum = self:ParseGUID(_G.UnitGUID("pet"))

    if unit_type ~= private.UNIT_TYPES.NPC or not unit_idnum then
        return
    end
    DBEntry("npcs", unit_idnum).mind_control = true
    print("Wiping action_data")
    table.wipe(action_data)
end


do
    local GENDER_NAMES = {
        "UNKNOWN",
        "MALE",
        "FEMALE",
    }


    local REACTION_NAMES = {
        "HATED",
        "HOSTILE",
        "UNFRIENDLY",
        "NEUTRAL",
        "FRIENDLY",
        "HONORED",
        "REVERED",
        "EXALTED",
    }


    local POWER_TYPE_NAMES = {
        ["0"] = "MANA",
        ["1"] = "RAGE",
        ["2"] = "FOCUS",
        ["3"] = "ENERGY",
        ["6"] = "RUNIC_POWER",
    }


    function WDP:PLAYER_TARGET_CHANGED()
        if not _G.UnitExists("target") or _G.UnitPlayerControlled("target") then
            return
        end
        local unit_type, unit_idnum = self:ParseGUID(_G.UnitGUID("target"))

        if unit_type ~= private.UNIT_TYPES.NPC or not unit_idnum then
            return
        end
        local npc = DBEntry("npcs", unit_idnum)
        local _, class_token = _G.UnitClass("target")
        npc.class = class_token

        UpdateFactionNames()
        DatamineTT:ClearLines()
        DatamineTT:SetUnit("target")

        for line_index = 1, DatamineTT:NumLines() do
            local current_line = _G["WDPDatamineTTTextLeft" .. line_index]

            if not current_line then
                break
            end
            local line_text = current_line:GetText()

            if faction_names[line_text] then
                npc.faction = line_text
                break
            end
        end
        npc.genders = npc.genders or {}
        npc.genders[GENDER_NAMES[_G.UnitSex("target")] or "UNDEFINED"] = true
        npc.is_pvp = _G.UnitIsPVP("target") and true or nil
        npc.reaction = ("%s:%s:%s"):format(_G.UnitLevel("player"), _G.UnitFactionGroup("player"), REACTION_NAMES[_G.UnitReaction("player", "target")])
        npc.encounter_data = npc.encounter_data or {}

        local npc_level = ("level_%d"):format(_G.UnitLevel("target"))

        if not npc.encounter_data[npc_level] then
            npc.encounter_data[npc_level] = {
                max_health = _G.UnitHealthMax("target"),
            }

            local max_power = _G.UnitManaMax("target")

            if max_power > 0 then
                local power_type = _G.UnitPowerType("target")
                npc.encounter_data[npc_level].power = ("%s:%d"):format(POWER_TYPE_NAMES[_G.tostring(power_type)] or power_type, max_power)
            end
        end
        table.wipe(action_data)
        action_data.type = AF.NPC
        action_data.identifier = unit_idnum
        action_data.npc_level = npc_level
    end
end -- do-block

do
    local function UpdateQuestJuncture(point)
        local unit_name = _G.UnitName("questnpc")

        if not unit_name then
            return
        end
        local unit_type, unit_id = WDP:ParseGUID(_G.UnitGUID("questnpc"))

        if unit_type == private.UNIT_TYPES.OBJECT then
            UpdateObjectLocation(unit_id)
        end
        local quest = DBEntry("quests", _G.GetQuestID())
        quest[point] = quest[point] or {}
        quest[point][("%s:%d"):format(private.UNIT_TYPE_NAMES[unit_type + 1], unit_id)] = true

        return quest
    end


    function WDP:QUEST_COMPLETE()
        UpdateQuestJuncture("end")
    end


    function WDP:QUEST_DETAIL()
        local quest = UpdateQuestJuncture("begin")

        quest.classes = quest.classes or {}
        quest.classes[PLAYER_CLASS] = true

        local _, race = _G.UnitRace("player")
        quest.races = quest.races or {}
        quest.races[race] = true
    end
end -- do-block


function WDP:QUEST_LOG_UPDATE()
    self:UnregisterEvent("QUEST_LOG_UPDATE")
end


function WDP:UNIT_QUEST_LOG_CHANGED(event, unit_id)
    if unit_id ~= "player" then
        return
    end
    self:RegisterEvent("QUEST_LOG_UPDATE")
end


function WDP:TRAINER_SHOW()
    if not _G.IsTradeskillTrainer() then
        return
    end
    local unit_type, unit_idnum = self:ParseGUID(_G.UnitGUID("target"))
    local npc = DBEntry("npcs", unit_idnum)
    npc.teaches = npc.teaches or {}

    -- Get the initial trainer filters
    local available = _G.GetTrainerServiceTypeFilter("available")
    local unavailable = _G.GetTrainerServiceTypeFilter("unavailable")
    local used = _G.GetTrainerServiceTypeFilter("used")

    -- Clear the trainer filters
    _G.SetTrainerServiceTypeFilter("available", 1)
    _G.SetTrainerServiceTypeFilter("unavailable", 1)
    _G.SetTrainerServiceTypeFilter("used", 1)

    for index = 1, _G.GetNumTrainerServices(), 1 do
        local spell_name, rank_name, _, _, required_level = _G.GetTrainerServiceInfo(index)

        if spell_name then
            DatamineTT:ClearLines()
            DatamineTT:SetTrainerService(index)

            local _, _, spell_id = DatamineTT:GetSpell()
            local profession, min_skill = _G.GetTrainerServiceSkillReq(index)
            profession = profession or "General"

            local class_professions = npc.teaches[PLAYER_CLASS]
            if not class_professions then
                npc.teaches[PLAYER_CLASS] = {}
                class_professions = npc.teaches[PLAYER_CLASS]
            end

            local profession_skills = class_professions[profession]
            if not profession_skills then
                class_professions[profession] = {}
                profession_skills = class_professions[profession]
            end
            profession_skills[spell_id] = ("%d:%d"):format(required_level, min_skill)
        end
    end

    -- Reset the filters to what they were before
    _G.SetTrainerServiceTypeFilter("available", available or 0)
    _G.SetTrainerServiceTypeFilter("unavailable", unavailable or 0)
    _G.SetTrainerServiceTypeFilter("used", used or 0)
end


function WDP:UNIT_SPELLCAST_SENT(event_name, unit_id, spell_name, spell_rank, target_name, spell_line)
    if private.tracked_line or unit_id ~= "player" then
        return
    end
    local spell_label = private.SPELL_LABELS_BY_NAME[spell_name]

    if not spell_label then
        return
    end
    table.wipe(action_data)

    local tt_item_name, tt_item_link = _G.GameTooltip:GetItem()
    local tt_unit_name, tt_unit_id = _G.GameTooltip:GetUnit()

    if not tt_unit_name and _G.UnitName("target") == target_name then
        tt_unit_name = target_name
        tt_unit_id = "target"
    end
    local spell_flags = private.SPELL_FLAGS_BY_LABEL[spell_label]

    if tt_unit_name and not tt_item_name then
        if bit.band(spell_flags, AF.NPC) == AF.NPC then
            if not tt_unit_id or tt_unit_name ~= target_name then
                return
            end
            action_data.type = AF.NPC
            action_data.label = spell_label:lower()
            action_data.unit_name = tt_unit_name
        end
    elseif bit.band(spell_flags, AF.ITEM) == AF.ITEM then
        action_data.type = AF.ITEM
        action_data.label = spell_label:lower()

        if tt_item_name and tt_item_name == target_name then
            action_data.item_id = ItemLinkToID(tt_item_link)
        elseif target_name and target_name ~= "" then
            local _, target_item_link = _G.GetItemInfo(target_name)
            action_data.item_id = ItemLinkToID(target_item_link)
        end
    elseif not tt_item_name and not tt_unit_name then
        local zone_name, area_id, x, y, map_level, instance_token = CurrentLocationData()

        action_data.instance_token = instance_token
        action_data.map_level = map_level
        action_data.name = target_name
        action_data.x = x
        action_data.y = y
        action_data.zone = ("%s:%d"):format(zone_name, area_id)

        if bit.band(spell_flags, AF.OBJECT) == AF.OBJECT then
            if target_name == "" then
                return
            end
            local identifier = ("%s:%s"):format(spell_label, target_name)
            UpdateObjectLocation(identifier)

            action_data.type = AF.OBJECT
            action_data.identifier = identifier
        elseif bit.band(spell_flags, AF.ZONE) == AF.ZONE then
            action_data.type = AF.ZONE
            action_data.label = spell_label:lower()
        end
    end

    --    print(("%s: '%s', '%s', '%s', '%s', '%s'"):format(event_name, unit_id, spell_name, spell_rank, target_name, spell_line))
    private.tracked_line = spell_line
end


function WDP:UNIT_SPELLCAST_SUCCEEDED(event_name, unit_id, spell_name, spell_rank, spell_line, spell_id)
    if unit_id ~= "player" then
        return
    end

    --    if private.SPELL_LABELS_BY_NAME[spell_name] then
    --        print(("%s: '%s', '%s', '%s', '%s', '%s'"):format(event_name, unit_id, spell_name, spell_rank, spell_line, spell_id))
    --    end
    private.tracked_line = nil
end

function WDP:HandleSpellFailure(event_name, unit_id, spell_name, spell_rank, spell_line, spell_id)
    if unit_id ~= "player" then
        return
    end

    if private.tracked_line == spell_line then
        private.tracked_line = nil
    end
end