local NP = NanamiPlates
local Settings = NP.Settings
local Colors = NP.Colors
local THREAT_COLORS = NP.THREAT_COLORS
local SpellDB = NanamiPlates_SpellDB
local Scanner = NanamiPlates_Scanner
local Healthbar = NanamiPlates_Healthbar

local pairs = pairs
local ipairs = ipairs
local type = type
local tostring = tostring
local tonumber = tonumber
local string_find = string.find
local string_lower = string.lower
local string_format = string.format
local string_gfind = string.gfind
local string_gsub = string.gsub
local string_sub = string.sub
local math_floor = math.floor
local GetTime = GetTime
local UnitExists = UnitExists
local UnitName = UnitName
local UnitLevel = UnitLevel
local UnitClass = UnitClass
local UnitIsUnit = UnitIsUnit
local UnitCanAttack = UnitCanAttack
local UnitIsFriend = UnitIsFriend
local UnitIsEnemy = UnitIsEnemy
local UnitDebuff = UnitDebuff
local UnitGUID = UnitGUID
local CreateFrame = CreateFrame

local registry = NP.registry
local superwow_active = NP.superwow_active
local playerClass = NP.playerClass
local platecount = 0
local playerInCombat = false

local REGION_ORDER = { "border", "glow", "name", "level", "levelicon", "raidicon" }
local DEBUFF_UPDATE_INTERVAL = 0.1

-- Quest mob detection: scans the quest log for kill objectives
-- and checks pfQuest tooltip data for item drop mobs
local questMobCache = {}
local questCacheTimer = 0
local QUEST_CACHE_INTERVAL = 2

local questMonsterPattern
do
    local raw = QUEST_MONSTERS_KILLED or "%s slain: %d/%d"
    raw = string.gsub(raw, "([%(%)%.%+%-%?%[%]%^%$%%])", "%%%1")
    raw = string.gsub(raw, "%%%%s", "(.+)")
    raw = string.gsub(raw, "%%%%d", "(%%d+)")
    questMonsterPattern = raw
end

local function RebuildQuestMobCache()
    for k in pairs(questMobCache) do questMobCache[k] = nil end

    local numEntries = GetNumQuestLogEntries()
    if not numEntries or numEntries == 0 then return end

    for qid = 1, numEntries do
        local title, level, _, header = GetQuestLogTitle(qid)
        if title and not header then
            local objectives = GetNumQuestLeaderBoards(qid)
            if objectives then
                for i = 1, objectives do
                    local text, objType, done = GetQuestLogLeaderBoard(i, qid)
                    if text and objType == "monster" and not done then
                        local _, _, mobName, current, needed = string_find(text, questMonsterPattern)
                        if not mobName then
                            _, _, mobName, current, needed = string_find(text, "^(.+):%s*(%d+)/(%d+)")
                        end
                        if mobName and current and needed then
                            if not questMobCache[mobName] or not questMobCache[mobName].done then
                                questMobCache[mobName] = {
                                    current = tonumber(current),
                                    needed = tonumber(needed),
                                    quest = title,
                                }
                            end
                        end
                    end
                end
            end
        end
    end
end

local function GetQuestMobInfo(plateName)
    if questMobCache[plateName] then
        return questMobCache[plateName]
    end
    if pfMap and pfMap.tooltips and pfMap.tooltips[plateName] then
        if next(pfMap.tooltips[plateName]) then
            return { tooltip = true }
        end
    end
    return nil
end

local function GetRankNumber(rankStr)
    if not rankStr then return 0 end
    for num in string_gfind(rankStr, "(%d+)") do
        return tonumber(num) or 0
    end
    return 0
end

local function ParseSpellName(spellString)
    if not spellString then return nil, 0 end
    for name, rank in string_gfind(spellString, "^(.+)%(Rank (%d+)%)$") do
        return name, tonumber(rank) or 0
    end
    return spellString, 0
end

-- Direct spell tracking: immediately records effect on target at cast time.
-- Even if the spell is resisted, the debuff icon won't appear on the nameplate,
-- so no incorrect timer will be displayed.
local function ClearSingleCurseTracking(targetName, guid, curseName)
    if not SpellDB or not curseName then return end
    if SpellDB.objects and SpellDB.objects[targetName] then
        for lvl, effects in pairs(SpellDB.objects[targetName]) do
            if effects[curseName] then effects[curseName] = nil end
        end
    end
    if guid and SpellDB.objects and SpellDB.objects[guid] then
        for lvl, effects in pairs(SpellDB.objects[guid]) do
            if effects[curseName] then effects[curseName] = nil end
        end
    end
    if NanamiPlates_Auras and NanamiPlates_Auras.timers then
        NanamiPlates_Auras.timers[targetName .. "_" .. curseName] = nil
        if guid then NanamiPlates_Auras.timers[guid .. "_" .. curseName] = nil end
    end
    if SpellDB.ownerBoundCache then
        if SpellDB.ownerBoundCache[targetName] then
            SpellDB.ownerBoundCache[targetName][curseName] = nil
        end
        if guid and SpellDB.ownerBoundCache[guid] then
            SpellDB.ownerBoundCache[guid][curseName] = nil
        end
    end
    if SpellDB.recentCasts then
        SpellDB.recentCasts[curseName] = nil
    end
end

local function ClearCurseTracking(targetName, guid, exceptCurse)
    if not SpellDB or not SpellDB.WARLOCK_CURSES then return end
    for curse, _ in pairs(SpellDB.WARLOCK_CURSES) do
        if curse ~= exceptCurse then
            if SpellDB.objects and SpellDB.objects[targetName] then
                for lvl, effects in pairs(SpellDB.objects[targetName]) do
                    if effects[curse] then effects[curse] = nil end
                end
            end
            if guid and SpellDB.objects and SpellDB.objects[guid] then
                for lvl, effects in pairs(SpellDB.objects[guid]) do
                    if effects[curse] then effects[curse] = nil end
                end
            end
            if NanamiPlates_Auras and NanamiPlates_Auras.timers then
                NanamiPlates_Auras.timers[targetName .. "_" .. curse] = nil
                if guid then NanamiPlates_Auras.timers[guid .. "_" .. curse] = nil end
            end
            if SpellDB.ownerBoundCache then
                if SpellDB.ownerBoundCache[targetName] then
                    SpellDB.ownerBoundCache[targetName][curse] = nil
                end
                if guid and SpellDB.ownerBoundCache[guid] then
                    SpellDB.ownerBoundCache[guid][curse] = nil
                end
            end
            if SpellDB.recentCasts then
                SpellDB.recentCasts[curse] = nil
            end
        end
    end
end

local function TrackSpellCast(spellName, duration)
    if not SpellDB or not spellName then return end
    if not UnitExists("target") then return end

    -- Translate localized spell name to English for DB consistency
    local englishName = spellName
    if SpellDB.localeMap and SpellDB.localeMap[spellName] then
        englishName = SpellDB.localeMap[spellName]
    elseif SpellDB.learnedLocale and SpellDB.learnedLocale[spellName] then
        englishName = SpellDB.learnedLocale[spellName]
    end

    -- Record this cast for locale learning
    if SpellDB.DEBUFFS and SpellDB.DEBUFFS[englishName] then
        SpellDB.lastCastSpell = englishName
    else
        SpellDB.lastCastSpell = spellName
    end
    SpellDB.lastCastTime = GetTime()

    -- Re-fetch duration with English name if original was localized
    if englishName ~= spellName and (not duration or duration <= 0) then
        duration = SpellDB:GetDuration(englishName, 0)
    end
    spellName = englishName

    if not duration or duration <= 0 then return end

    local targetName = UnitName("target")
    local targetLevel = UnitLevel("target") or 0
    local guid = UnitGUID and UnitGUID("target")

    if SpellDB.WARLOCK_CURSES and SpellDB.WARLOCK_CURSES[spellName] then
        if not SpellDB:HasMalediction() then
            ClearCurseTracking(targetName, guid, spellName)
        else
            if spellName == "Curse of Doom" then
                ClearCurseTracking(targetName, guid, spellName)
            elseif spellName == SpellDB.WARLOCK_AGONY_CURSE then
                -- Agony cast: clear only Doom tracking, keep other curses
                ClearSingleCurseTracking(targetName, guid, "Curse of Doom")
            elseif SpellDB.WARLOCK_LONG_CURSES and SpellDB.WARLOCK_LONG_CURSES[spellName] then
                -- Long curse cast: clear other long curses + Doom, keep Agony
                for curse, _ in pairs(SpellDB.WARLOCK_CURSES) do
                    if curse ~= spellName and curse ~= SpellDB.WARLOCK_AGONY_CURSE then
                        ClearSingleCurseTracking(targetName, guid, curse)
                    end
                end
            end
        end
    end

    SpellDB:AddPending(targetName, targetLevel, spellName, duration)
    SpellDB:RefreshEffect(targetName, targetLevel, spellName, duration, true)

    if guid then
        SpellDB:RefreshEffect(guid, targetLevel, spellName, duration, true)
    end

    if SpellDB.OWNER_BOUND_DEBUFFS and SpellDB.OWNER_BOUND_DEBUFFS[spellName] then
        SpellDB:TrackOwnerBoundDebuff(targetName, spellName, duration)
        if guid then SpellDB:TrackOwnerBoundDebuff(guid, spellName, duration) end
    end

    if NanamiPlates_Auras and NanamiPlates_Auras.timers then
        NanamiPlates_Auras.timers[targetName .. "_" .. spellName] = nil
        if guid then NanamiPlates_Auras.timers[guid .. "_" .. spellName] = nil end
    end

    -- Malediction auto-apply: casting Recklessness/Shadow/Elements also applies max rank Agony
    if SpellDB:HasMalediction() and SpellDB.MALEDICTION_AUTO_AGONY
        and SpellDB.MALEDICTION_AUTO_AGONY[spellName] then
        local agonyName = SpellDB.WARLOCK_AGONY_CURSE
        local agonyDuration = SpellDB:GetDuration(agonyName, 0)
        if agonyDuration and agonyDuration > 0 then
            SpellDB:RefreshEffect(targetName, targetLevel, agonyName, agonyDuration, true)
            if guid then
                SpellDB:RefreshEffect(guid, targetLevel, agonyName, agonyDuration, true)
            end
            if SpellDB.OWNER_BOUND_DEBUFFS and SpellDB.OWNER_BOUND_DEBUFFS[agonyName] then
                SpellDB:TrackOwnerBoundDebuff(targetName, agonyName, agonyDuration)
                if guid then SpellDB:TrackOwnerBoundDebuff(guid, agonyName, agonyDuration) end
            end
            if NanamiPlates_Auras and NanamiPlates_Auras.timers then
                NanamiPlates_Auras.timers[targetName .. "_" .. agonyName] = nil
                if guid then NanamiPlates_Auras.timers[guid .. "_" .. agonyName] = nil end
            end
        end
    end
end

-- Spell cast hooks
local Original_CastSpell = CastSpell
CastSpell = function(spellId, bookType)
    if SpellDB and spellId and bookType then
        local spellName, rank = GetSpellName(spellId, bookType)
        if spellName and UnitExists("target") and UnitCanAttack("player", "target") then
            local duration = SpellDB:GetDuration(spellName, rank)
            TrackSpellCast(spellName, duration)
        end
    end
    return Original_CastSpell(spellId, bookType)
end

local Original_CastSpellByName = CastSpellByName
CastSpellByName = function(spellString, onSelf)
    if SpellDB and spellString then
        local spellName, rank = ParseSpellName(spellString)
        if spellName and UnitExists("target") and UnitCanAttack("player", "target") then
            local duration = SpellDB:GetDuration(spellName, rank)
            TrackSpellCast(spellName, duration)
        end
    end
    return Original_CastSpellByName(spellString, onSelf)
end

local Original_UseAction = UseAction
UseAction = function(slot, checkCursor, onSelf)
    if SpellDB and slot then
        local actionTexture = GetActionTexture(slot)
        if GetActionText(slot) == nil and actionTexture ~= nil then
            local spellName, rank = SpellDB:ScanAction(slot)
            if spellName then
                if SpellDB.textureToSpell then
                    local existing = SpellDB.textureToSpell[actionTexture]
                    if not existing or not SpellDB.DEBUFFS[existing] then
                        SpellDB.textureToSpell[actionTexture] = spellName
                    end
                    -- If spellName is localized and existing is English, learn mapping
                    if existing and SpellDB.DEBUFFS[existing] and spellName ~= existing then
                        if SpellDB.LearnLocale then
                            SpellDB:LearnLocale(spellName, existing)
                        end
                        spellName = existing
                    end
                end
                local duration = SpellDB:GetDuration(spellName, rank)
                TrackSpellCast(spellName, duration)
            end
        end
    end
    return Original_UseAction(slot, checkCursor, onSelf)
end

if SpellDB then SpellDB:InitScanner() end

local function DisableObject(obj)
    if not obj then return end
    obj:Hide()
    obj:SetAlpha(0)
    if obj.SetWidth then obj:SetWidth(0.001) end
    if obj.SetHeight then obj:SetHeight(0.001) end
end

local BORDER_PAD = 2

local function CreateNanamiBackdrop(frame)
    local bgR, bgG, bgB, bgA = NP.GetThemeColor("panelBg", 0.1, 0.06, 0.1, 0.85)
    local brR, brG, brB, brA = NP.GetThemeColor("panelBorder", 0.55, 0.30, 0.42, 0.9)

    frame:SetBackdrop({
        bgFile = "Interface\\Buttons\\WHITE8X8",
        edgeFile = "Interface\\Tooltips\\UI-Tooltip-Border",
        tile = false, tileSize = 0, edgeSize = 10,
        insets = { left = BORDER_PAD, right = BORDER_PAD, top = BORDER_PAD, bottom = BORDER_PAD }
    })
    frame:SetBackdropColor(bgR, bgG, bgB, bgA)
    frame:SetBackdropBorderColor(brR, brG, brB, brA)
end

local ARROW_TEXTURE = "Interface\\AddOns\\Nanami-Plates\\img\\arrow"
local ARROW_TEXCOORDS = {
    {0, 0.5, 0, 0.5},
    {0.5, 1, 0, 0.5},
    {0, 0.5, 0.5, 1},
    {0.5, 1, 0.5, 1},
}
NP.ARROW_TEXCOORDS = ARROW_TEXCOORDS

local function SetArrowTexCoords(f)
    if not f or not f.tex then return end
    local style = Settings.targetArrowStyle or 1
    local coords = ARROW_TEXCOORDS[style] or ARROW_TEXCOORDS[1]
    if f.side == "RIGHT" then
        f.tex:SetTexCoord(coords[2], coords[1], coords[3], coords[4])
    else
        f.tex:SetTexCoord(coords[1], coords[2], coords[3], coords[4])
    end
end

local function UpdateArrowPosition(f, healthBG)
    if not f or not healthBG then return end
    local offset = Settings.targetArrowOffset or 0
    f:ClearAllPoints()
    if f.side == "LEFT" then
        f:SetPoint("RIGHT", healthBG, "LEFT", -offset, 0)
    else
        f:SetPoint("LEFT", healthBG, "RIGHT", offset, 0)
    end
end

local function CreateArrowIndicator(parent, healthBG, side)
    local size = Settings.targetArrowSize or 24

    local f = CreateFrame("Frame", nil, parent)
    f:SetWidth(size)
    f:SetHeight(size)
    f:SetFrameLevel(parent:GetFrameLevel() + 10)
    f.side = side
    f.healthBG = healthBG

    UpdateArrowPosition(f, healthBG)

    local tex = f:CreateTexture(nil, "OVERLAY")
    tex:SetTexture(ARROW_TEXTURE)
    tex:SetAllPoints(f)
    f.tex = tex

    SetArrowTexCoords(f)

    f:Hide()
    return f
end

function NP.UpdateAllArrows()
    local size = Settings.targetArrowSize or 24
    for frame, np in pairs(registry) do
        if np.targetArrowL then
            np.targetArrowL:SetWidth(size)
            np.targetArrowL:SetHeight(size)
            SetArrowTexCoords(np.targetArrowL)
            UpdateArrowPosition(np.targetArrowL, np.targetArrowL.healthBG)
        end
        if np.targetArrowR then
            np.targetArrowR:SetWidth(size)
            np.targetArrowR:SetHeight(size)
            SetArrowTexCoords(np.targetArrowR)
            UpdateArrowPosition(np.targetArrowR, np.targetArrowR.healthBG)
        end
    end
end

local function HandleNamePlate(frame)
    if registry[frame] then return end

    platecount = platecount + 1
    local plateName = "NanamiPlate" .. platecount

    local r1, r2, r3, r4, r5, r6 = frame:GetRegions()
    local regions = {r1, r2, r3, r4, r5, r6}

    local original = {}
    for i, key in ipairs(REGION_ORDER) do
        original[key] = regions[i]
    end

    local children = { frame:GetChildren() }
    original.healthbar = children[1]
    if children[2] and children[2].GetObjectType and children[2]:GetObjectType() == "StatusBar" then
        original.castbar = children[2]
    end

    original.name = original.name or r3
    original.level = original.level or r4

    -- Set parent to 1x1 to fully disable engine anti-overlap (ShaguPlates technique)
    -- Custom stacking in ResolveStacking() handles overlap instead
    frame:SetHeight(1)
    frame:SetWidth(1)

    -- Create overlay
    local np = CreateFrame("Button", plateName, frame)
    np:SetAllPoints(frame)
    np:SetFrameLevel(frame:GetFrameLevel() + 1)
    np:EnableMouse(false)
    local rawStrata = np:GetFrameStrata()
    local VALID_STRATA = { BACKGROUND=1, LOW=1, MEDIUM=1, HIGH=1, DIALOG=1, FULLSCREEN=1, FULLSCREEN_DIALOG=1, TOOLTIP=1 }
    np._defaultStrata = VALID_STRATA[rawStrata] and rawStrata or "BACKGROUND"

    np.original = original

    -- Health bar background frame (also contains mana bar)
    local healthBG = CreateFrame("Frame", nil, np)
    healthBG:SetHeight(Settings.healthbarHeight + BORDER_PAD * 2)
    healthBG:SetWidth(Settings.healthbarWidth + BORDER_PAD * 2)
    healthBG:SetPoint("CENTER", np, "CENTER", 0, Settings.nameplateYOffset or 0)
    CreateNanamiBackdrop(healthBG)
    np.healthBG = healthBG

    -- Health bar (single anchor + explicit size, so mana can fit below)
    local health = CreateFrame("StatusBar", plateName .. "Health", healthBG)
    health:SetStatusBarTexture(NP.GetTexture())
    health:SetPoint("TOPLEFT", healthBG, "TOPLEFT", BORDER_PAD, -BORDER_PAD)
    health:SetWidth(Settings.healthbarWidth)
    health:SetHeight(Settings.healthbarHeight)
    health:SetMinMaxValues(0, 1)
    health:SetValue(1)
    np.health = health

    local healthBGTex = health:CreateTexture(nil, "BACKGROUND")
    healthBGTex:SetAllPoints(health)
    healthBGTex:SetTexture(NP.GetTexture())
    healthBGTex:SetVertexColor(0.15, 0.15, 0.15, 0.8)
    np.healthBGTex = healthBGTex

    -- Target highlight: additive StatusBar overlay that brightens only the filled portion
    local targetGlow = CreateFrame("StatusBar", nil, healthBG)
    targetGlow:SetAllPoints(health)
    targetGlow:SetStatusBarTexture(NP.GetTexture())
    targetGlow:SetFrameLevel(health:GetFrameLevel() + 1)
    targetGlow:SetMinMaxValues(0, 1)
    targetGlow:SetValue(1)
    targetGlow:SetAlpha(0.35)
    targetGlow:Hide()
    np.targetGlow = targetGlow
    local glowRegions = { targetGlow:GetRegions() }
    for _, reg in ipairs(glowRegions) do
        if reg and reg.SetBlendMode then reg:SetBlendMode("ADD") end
    end

    -- Mana/Energy/Rage bar (inside healthBG, below health bar)
    local manaBar = CreateFrame("StatusBar", plateName .. "Mana", healthBG)
    manaBar:SetStatusBarTexture(NP.GetTexture())
    manaBar:SetPoint("TOPLEFT", health, "BOTTOMLEFT", 0, -1)
    manaBar:SetWidth(Settings.healthbarWidth)
    manaBar:SetHeight(Settings.manabarHeight or 3)
    manaBar:SetMinMaxValues(0, 1)
    manaBar:SetValue(1)
    manaBar:SetStatusBarColor(0, 0, 1, 1)
    manaBar:Hide()
    np.manaBar = manaBar

    local manaBGTex = manaBar:CreateTexture(nil, "BACKGROUND")
    manaBGTex:SetAllPoints(manaBar)
    manaBGTex:SetTexture(NP.GetTexture())
    manaBGTex:SetVertexColor(0.05, 0.05, 0.1, 0.8)

    -- Thin separator line between health and mana
    local brR, brG, brB = NP.GetThemeColor("panelBorder", 0.55, 0.30, 0.42, 0.9)
    local manaSep = healthBG:CreateTexture(nil, "ARTWORK")
    manaSep:SetTexture("Interface\\Buttons\\WHITE8X8")
    manaSep:SetHeight(1)
    manaSep:SetPoint("TOPLEFT", health, "BOTTOMLEFT", 0, 0)
    manaSep:SetPoint("TOPRIGHT", health, "BOTTOMRIGHT", 0, 0)
    manaSep:SetVertexColor(brR, brG, brB, 0.5)
    manaSep:Hide()
    np.manaSep = manaSep

    -- Health text
    local healthText = health:CreateFontString(nil, "OVERLAY")
    healthText:SetFont(NP.GetFont(), Settings.healthFontSize, NP.GetFontOutline())
    healthText:SetPoint("TOPRIGHT", health, "TOPRIGHT", -2, 0)
    healthText:SetPoint("BOTTOMRIGHT", health, "BOTTOMRIGHT", -2, 0)
    healthText:SetJustifyV("MIDDLE")
    healthText:SetJustifyH("RIGHT")
    healthText:SetTextColor(1, 1, 1, 1)
    np.healthText = healthText

    -- Threat percentage text
    local threatPctText = health:CreateFontString(nil, "OVERLAY")
    threatPctText:SetFont(NP.GetFont(), Settings.healthFontSize, NP.GetFontOutline())
    threatPctText:SetPoint("CENTER", health, "CENTER", 0, 0)
    threatPctText:SetTextColor(1, 1, 1, 1)
    threatPctText:SetText("")
    np.threatPctText = threatPctText

    -- Name text
    local name = np:CreateFontString(nil, "OVERLAY")
    name:SetFont(NP.GetFont(), Settings.nameFontSize, NP.GetFontOutline())
    name:SetPoint("BOTTOM", healthBG, "TOP", 0, 2)
    name:SetTextColor(1, 1, 1, 1)
    np.name = name

    -- Level text (on health bar so it renders above the bar fill)
    local level = health:CreateFontString(nil, "OVERLAY")
    level:SetFont(NP.GetFont(), Settings.levelFontSize, NP.GetFontOutline())
    level:SetPoint("TOPLEFT", health, "TOPLEFT", 2, 0)
    level:SetPoint("BOTTOMLEFT", health, "BOTTOMLEFT", 2, 0)
    level:SetJustifyV("MIDDLE")
    level:SetJustifyH("LEFT")
    level:SetTextColor(1, 1, 0.6, 1)
    np.level = level

    -- Raid icon
    local raidIcon = np:CreateTexture(nil, "OVERLAY")
    raidIcon:SetTexture("Interface\\TargetingFrame\\UI-RaidTargetingIcons")
    raidIcon:SetWidth(16)
    raidIcon:SetHeight(16)
    raidIcon:SetPoint("LEFT", healthBG, "RIGHT", 3, 0)
    raidIcon:Hide()
    np.raidIcon = raidIcon

    -- Castbar background (anchors dynamically below healthBG)
    local castbarBG = CreateFrame("Frame", nil, np)
    castbarBG:SetHeight(Settings.castbarHeight + 2)
    castbarBG:SetWidth(Settings.healthbarWidth + 2)
    castbarBG:SetPoint("TOP", healthBG, "BOTTOM", 0, -1)
    CreateNanamiBackdrop(castbarBG)
    castbarBG:Hide()
    np.castbarBG = castbarBG

    -- Castbar
    local castbar = CreateFrame("StatusBar", plateName .. "Castbar", castbarBG)
    castbar:SetStatusBarTexture(NP.GetTexture())
    castbar:SetPoint("TOPLEFT", castbarBG, "TOPLEFT", 1, -1)
    castbar:SetPoint("BOTTOMRIGHT", castbarBG, "BOTTOMRIGHT", -1, 1)
    castbar:SetMinMaxValues(0, 1)
    castbar:SetValue(0)
    castbar:SetStatusBarColor(Settings.castbarColor[1], Settings.castbarColor[2], Settings.castbarColor[3], Settings.castbarColor[4])
    np.castbar = castbar

    local castbarBGTex = castbar:CreateTexture(nil, "BACKGROUND")
    castbarBGTex:SetAllPoints(castbar)
    castbarBGTex:SetTexture(NP.GetTexture())
    castbarBGTex:SetVertexColor(0.1, 0.1, 0.1, 0.8)

    local castbarText = castbar:CreateFontString(nil, "OVERLAY")
    castbarText:SetFont(NP.GetFont(), Settings.healthFontSize - 1, NP.GetFontOutline())
    castbarText:SetPoint("CENTER", castbar, "CENTER", 0, 0)
    castbarText:SetTextColor(1, 1, 1, 1)
    np.castbarText = castbarText

    local castbarTimer = castbar:CreateFontString(nil, "OVERLAY")
    castbarTimer:SetFont(NP.GetFont(), Settings.healthFontSize - 1, NP.GetFontOutline())
    castbarTimer:SetPoint("RIGHT", castbar, "RIGHT", -2, 0)
    castbarTimer:SetTextColor(1, 1, 1, 1)
    np.castbarTimer = castbarTimer

    -- Castbar icon (anchored to castbar, not healthbar, to avoid chevron overlap)
    local castbarIcon = castbarBG:CreateTexture(nil, "OVERLAY")
    castbarIcon:SetWidth(Settings.castbarHeight + 8)
    castbarIcon:SetHeight(Settings.castbarHeight + 8)
    castbarIcon:SetPoint("RIGHT", castbarBG, "LEFT", -2, 0)
    castbarIcon:SetTexCoord(0.08, 0.92, 0.08, 0.92)
    castbarIcon:Hide()
    np.castbarIcon = castbarIcon

    -- Create aura frames (filled in by Auras module)
    if NanamiPlates_Auras then
        NanamiPlates_Auras:CreateDebuffFrames(np)
    end

    -- Create combo point frames (filled in by ComboPoints module)
    if NanamiPlates_ComboPoints then
        NanamiPlates_ComboPoints:CreateComboPointFrames(np)
    end

    -- Quest mob indicator icon (yellow "!" to the left of the name)
    local questIcon = np:CreateTexture(nil, "OVERLAY")
    questIcon:SetTexture("Interface\\GossipFrame\\AvailableQuestIcon")
    questIcon:SetWidth(12)
    questIcon:SetHeight(12)
    questIcon:SetPoint("RIGHT", name, "LEFT", -1, 0)
    questIcon:Hide()
    np.questIcon = questIcon

    -- Quest progress text (e.g. "3/8" to the right of the name)
    local questText = np:CreateFontString(nil, "OVERLAY")
    questText:SetFont(NP.GetFont(), Settings.nameFontSize - 1, NP.GetFontOutline())
    questText:SetPoint("LEFT", name, "RIGHT", 2, 0)
    questText:SetTextColor(1, 0.82, 0, 1)
    questText:Hide()
    np.questText = questText

    -- Target arrow indicators  >> [healthbar] <<
    np.targetArrowL = CreateArrowIndicator(np, healthBG, "LEFT")
    np.targetArrowR = CreateArrowIndicator(np, healthBG, "RIGHT")

    -- Hide original elements thoroughly (keep healthbar color intact for unit type detection)
    for _, key in ipairs(REGION_ORDER) do
        if original[key] then DisableObject(original[key]) end
    end
    if original.healthbar then
        local hbRegions = { original.healthbar:GetRegions() }
        for _, reg in ipairs(hbRegions) do
            if reg and reg.Hide then reg:Hide() end
            if reg and reg.SetAlpha then reg:SetAlpha(0) end
        end
        original.healthbar:ClearAllPoints()
        original.healthbar:SetPoint("BOTTOMLEFT", frame, "BOTTOMLEFT", 0, 0)
        original.healthbar:SetWidth(0.001)
        original.healthbar:SetHeight(0.001)
    end
    if original.castbar then
        original.castbar:SetAlpha(0.001)
        local cbRegions = { original.castbar:GetRegions() }
        for _, reg in ipairs(cbRegions) do
            if reg and reg.SetAlpha then reg:SetAlpha(0) end
        end
    end

    -- Tracking state
    np.isTarget = false
    np.lastDebuffUpdate = 0
    np.unitstr = nil
    np.plateName = nil
    np._lastFriendly = nil
    np._lastManaShowing = nil
    np._lastFriendly_resize = nil

    frame.nameplate = np
    registry[frame] = np

    -- OnShow: reset and re-hide original elements
    local oldOnShow = frame:GetScript("OnShow")
    frame:SetScript("OnShow", function()
        if oldOnShow then oldOnShow() end
        this:SetHeight(1)
        this:SetWidth(1)
        local nameplate = this.nameplate
        if nameplate then
            Healthbar.ResetCache(nameplate)
            nameplate.isTarget = false
            nameplate._isTargetStrata = nil
            nameplate.lastDebuffUpdate = 0
            nameplate.unitstr = nil
            nameplate._lastFriendly = nil
            nameplate._lastManaShowing = nil
            nameplate._lastFriendly_resize = nil
            nameplate._lastAlpha = nil
            nameplate._stackY = nil
            nameplate._appliedOffY = nil
            nameplate.healthBG:ClearAllPoints()
            nameplate.healthBG:SetPoint("CENTER", nameplate, "CENTER", 0, Settings.nameplateYOffset or 0)
            if nameplate._defaultStrata then
                nameplate:SetFrameStrata(nameplate._defaultStrata)
            end
            nameplate.castbarBG:Hide()
            nameplate.castbarIcon:Hide()
            nameplate.manaBar:Hide()
            if nameplate.manaSep then nameplate.manaSep:Hide() end
            if nameplate.targetArrowL then nameplate.targetArrowL:Hide() end
            if nameplate.targetArrowR then nameplate.targetArrowR:Hide() end
            if nameplate.comboPoints then
                for i = 1, 5 do
                    if nameplate.comboPoints[i] then nameplate.comboPoints[i]:Hide() end
                end
            end
            if nameplate.questIcon then nameplate.questIcon:Hide() end
            if nameplate.questText then nameplate.questText:Hide() end

            -- Re-hide original elements (Blizzard resets them on show)
            local orig = nameplate.original
            for _, key in ipairs(REGION_ORDER) do
                if orig[key] then
                    orig[key]:Hide()
                    if orig[key].SetAlpha then orig[key]:SetAlpha(0) end
                end
            end
            if orig.healthbar then
                orig.healthbar:SetWidth(0.001)
                orig.healthbar:SetHeight(0.001)
                local hbRegions = { orig.healthbar:GetRegions() }
                for _, reg in ipairs(hbRegions) do
                    if reg and reg.Hide then reg:Hide() end
                end
            end
            if orig.castbar then
                orig.castbar:SetAlpha(0.001)
                local cbRegions = { orig.castbar:GetRegions() }
                for _, reg in ipairs(cbRegions) do
                    if reg and reg.SetAlpha then reg:SetAlpha(0) end
                end
            end

            if Healthbar.ShouldSkipNameplate(this, nameplate, nameplate.original, Settings) then
                nameplate:Hide()
            else
                nameplate:Show()
            end
        end
    end)

    -- OnHide: cleanup
    local oldOnHide = frame:GetScript("OnHide")
    frame:SetScript("OnHide", function()
        if oldOnHide then oldOnHide() end
        local nameplate = this.nameplate
        if nameplate then
            nameplate.castbarBG:Hide()
            nameplate.castbarIcon:Hide()
            nameplate.manaBar:Hide()
            if nameplate.manaSep then nameplate.manaSep:Hide() end
            if nameplate.targetArrowL then nameplate.targetArrowL:Hide() end
            if nameplate.targetArrowR then nameplate.targetArrowR:Hide() end
            if nameplate.questIcon then nameplate.questIcon:Hide() end
            if nameplate.questText then nameplate.questText:Hide() end
        end
    end)
end

local function ShortenNumber(n)
    if n >= 1000000 then
        return string_format("%.1fM", n / 1000000)
    elseif n >= 10000 then
        return string_format("%.1fK", n / 1000)
    else
        return tostring(n)
    end
end

local function FormatHealthText(current, max, format)
    if not format or format == 0 then return "" end
    if max == 0 then return "" end
    local pct = math_floor(current / max * 100 + 0.5)
    if format == 1 then return pct .. "%" end
    if format == 2 then return ShortenNumber(current) end
    if format == 3 then return ShortenNumber(current) .. " (" .. pct .. "%)" end
    if format == 4 then return ShortenNumber(current) .. "/" .. ShortenNumber(max) end
    if format == 5 then return ShortenNumber(current) .. "/" .. ShortenNumber(max) .. " " .. pct .. "%" end
    return pct .. "%"
end

local function GetLevelDiffColor(unitLevel)
    local playerLevel = UnitLevel("player") or 60
    local diff = unitLevel - playerLevel
    if diff >= 5 then return 1, 0, 0
    elseif diff >= 3 then return 1, 0.5, 0
    elseif diff >= -2 then return 1, 1, 0
    elseif diff >= -4 - math_floor(playerLevel / 10) then return 0.25, 0.75, 0.25
    else return 0.5, 0.5, 0.5
    end
end

local function HideOriginalElements(original)
    for _, key in ipairs(REGION_ORDER) do
        local obj = original[key]
        if obj and obj.IsShown and obj:IsShown() then
            obj:Hide()
            if obj.SetAlpha then obj:SetAlpha(0) end
        end
    end
    if original.castbar and original.castbar:GetAlpha() > 0.01 then
        original.castbar:SetAlpha(0.001)
    end
end

local function UpdateNamePlate(frame)
    local np = frame.nameplate
    if not np then return end
    if not np:IsShown() then return end

    local original = np.original
    if not original or not original.healthbar then return end

    -- Keep parent 1x1 to disable engine anti-overlap entirely
    if frame:GetHeight() > 1 or frame:GetWidth() > 1 then
        frame:SetHeight(1)
        frame:SetWidth(1)
    end

    -- Continuously enforce hiding of original elements
    HideOriginalElements(original)

    -- Unit name
    local plateName = ""
    if original.name and original.name.GetText then
        plateName = original.name:GetText() or ""
    end
    np.plateName = plateName
    np.name:SetText(plateName)

    -- SuperWoW unit detection
    local unitstr = nil
    local hasValidGUID = false
    if superwow_active and frame.GetName then
        unitstr = frame:GetName(1)
        if unitstr and UnitExists(unitstr) then
            hasValidGUID = true
        else
            unitstr = nil
        end
    end
    np.unitstr = unitstr

    -- Unit type detection
    local isHostile, isNeutral, isFriendly, origR, origG, origB = Healthbar.DetectUnitType(np, original)
    Healthbar.CheckUnitChange(np, plateName, isNeutral)

    -- Override neutral→hostile when the mob has entered combat (e.g. after player attacks it)
    if (isNeutral or np.wasNeutral) and unitstr and hasValidGUID
        and UnitAffectingCombat and UnitAffectingCombat(unitstr) then
        isHostile = true
        isNeutral = false
        isFriendly = false
        np.wasNeutral = false
    end

    local isFriendlyStyle = isFriendly

    -- Tapped detection: mob tagged by another player outside our group (unlootable)
    local isTapped = false
    if unitstr and hasValidGUID and UnitIsTapped then
        if UnitIsTapped(unitstr) and (not UnitIsTappedByPlayer or not UnitIsTappedByPlayer(unitstr)) then
            isTapped = true
        end
    end
    -- Color fallback: hostile/neutral/friendly all have B≈0; tapped grey has B>0
    if not isTapped and not isHostile and not isNeutral and origB > 0.1 and origR > 0.15 then
        isTapped = true
    end
    if isTapped then
        isFriendlyStyle = false
    end

    -- Health values
    local hp = original.healthbar:GetValue() or 0
    local _, hpmax = original.healthbar:GetMinMaxValues()
    hpmax = hpmax or 1
    if hpmax == 0 then hpmax = 1 end
    np.health:SetMinMaxValues(0, hpmax)
    np.health:SetValue(hp)
    if np.targetGlow then
        np.targetGlow:SetMinMaxValues(0, hpmax)
        np.targetGlow:SetValue(hp)
    end

    -- Dimensions (only update when style changes)
    local hHeight, hWidth, hFontSize, lFontSize, nFontSize, hTextFormat
    if isFriendlyStyle then
        hHeight = Settings.friendHealthbarHeight
        hWidth = Settings.friendHealthbarWidth
        hFontSize = Settings.friendHealthFontSize
        lFontSize = Settings.friendLevelFontSize
        nFontSize = Settings.friendNameFontSize
        hTextFormat = Settings.friendHealthTextFormat
    else
        hHeight = Settings.healthbarHeight
        hWidth = Settings.healthbarWidth
        hFontSize = Settings.healthFontSize
        lFontSize = Settings.levelFontSize
        nFontSize = Settings.nameFontSize
        hTextFormat = Settings.healthTextFormat
    end

    if np._lastFriendly ~= isFriendlyStyle then
        np._lastFriendly = isFriendlyStyle
        np.health:SetWidth(hWidth)
        np.health:SetHeight(hHeight)
        np.name:SetFont(NP.GetFont(), nFontSize, NP.GetFontOutline())
        np.level:SetFont(NP.GetFont(), lFontSize, NP.GetFontOutline())
        np.healthText:SetFont(NP.GetFont(), hFontSize, NP.GetFontOutline())
    end

    -- Health text
    np.healthText:SetText(FormatHealthText(hp, hpmax, hTextFormat))

    -- Level text and classification
    local unitLevel = nil
    local isBoss = original.levelicon and original.levelicon.IsShown and original.levelicon:IsShown()
    local levelText = (original.level and original.level.GetText) and original.level:GetText() or nil

    if levelText then
        unitLevel = tonumber(levelText)
    end

    local classification = "normal"
    if isBoss then
        classification = "worldboss"
    elseif isTarget and UnitExists("target") and UnitClassification then
        classification = UnitClassification("target") or "normal"
    elseif unitstr and UnitExists(unitstr) and UnitClassification then
        classification = UnitClassification(unitstr) or "normal"
    elseif original.border and original.border.GetVertexColor then
        local br, bg, bb = original.border:GetVertexColor()
        if br and bg and bb and br > 0.6 and bg > 0.5 and bb < 0.3 then
            classification = "elite"
        end
    end

    if classification == "worldboss" then
        np.level:SetText("??")
        np.level:SetTextColor(1, 0, 0)
    elseif levelText then
        if classification == "rareelite" then
            np.level:SetText(levelText .. "+")
            np.level:SetTextColor(0.8, 0.8, 0.8)
        elseif classification == "elite" then
            np.level:SetText(levelText .. "+")
            if unitLevel then
                local lr, lg, lb = GetLevelDiffColor(unitLevel)
                np.level:SetTextColor(lr, lg, lb)
            else
                np.level:SetTextColor(1, 1, 0.6)
            end
        elseif classification == "rare" then
            np.level:SetText(levelText)
            np.level:SetTextColor(0.8, 0.8, 0.8)
        else
            np.level:SetText(levelText)
            if unitLevel then
                local lr, lg, lb = GetLevelDiffColor(unitLevel)
                np.level:SetTextColor(lr, lg, lb)
            else
                np.level:SetTextColor(1, 1, 0.6)
            end
        end
    end

    -- Raid icon
    if original.raidicon and original.raidicon.IsShown and original.raidicon:IsShown() then
        local ux, uy = original.raidicon:GetTexCoord()
        np.raidIcon:SetTexCoord(ux, ux + 0.25, uy, uy + 0.25)
        np.raidIcon:Show()
    else
        np.raidIcon:Hide()
    end

    -- Quest mob indicator
    if Settings.showQuestIcon and not isFriendlyStyle then
        local questInfo = GetQuestMobInfo(plateName)
        if questInfo then
            if not np.questIcon:IsShown() then np.questIcon:Show() end
            if questInfo.current and questInfo.needed then
                np.questText:SetText(questInfo.current .. "/" .. questInfo.needed)
                if not np.questText:IsShown() then np.questText:Show() end
            else
                if np.questText:IsShown() then np.questText:Hide() end
            end
        else
            if np.questIcon:IsShown() then np.questIcon:Hide() end
            if np.questText:IsShown() then np.questText:Hide() end
        end
    else
        if np.questIcon:IsShown() then np.questIcon:Hide() end
        if np.questText:IsShown() then np.questText:Hide() end
    end

    -- Health bar color
    local barR, barG, barB = origR, origG, origB

    if isTapped then
        barR, barG, barB = Colors.tapped[1], Colors.tapped[2], Colors.tapped[3]
    elseif isHostile then
        barR, barG, barB = Colors.hostile[1], Colors.hostile[2], Colors.hostile[3]
    elseif isNeutral or Healthbar.WasNeutral(np) then
        barR, barG, barB = Colors.neutral[1], Colors.neutral[2], Colors.neutral[3]
    elseif isFriendly then
        barR, barG, barB = Colors.friendly[1], Colors.friendly[2], Colors.friendly[3]
    else
        barR, barG, barB = Colors.hostile[1], Colors.hostile[2], Colors.hostile[3]
    end

    -- Class colors for players
    if unitstr and hasValidGUID and UnitIsPlayer(unitstr) then
        local _, unitClass = UnitClass(unitstr)
        if unitClass and Colors.class[unitClass] then
            barR = Colors.class[unitClass][1]
            barG = Colors.class[unitClass][2]
            barB = Colors.class[unitClass][3]
        end
    end

    -- Threat coloring (overrides basic colors for hostile mobs)
    if isHostile and not isTapped then
        local threatColor = nil
        local mobGUID = unitstr
        local threatPctValue = nil
        local threatPctRole = NP.playerRole or "DPS"

        if NanamiPlates_Threat then
            local hasData, playerHasAggro, otherName, otherPct = NanamiPlates_Threat.GetTWTankModeThreat(mobGUID, plateName)

            if hasData then
                local role = threatPctRole
                if role == "TANK" then
                    if playerHasAggro then
                        threatColor = THREAT_COLORS.TANK.AGGRO
                        threatPctValue = 100
                    elseif otherPct and otherPct > 70 then
                        threatColor = THREAT_COLORS.TANK.LOSING_AGGRO
                        threatPctValue = otherPct
                    elseif otherName and NP.TANK_CLASSES and NP.GetPlayerClassByName then
                        local otherClass = NP.GetPlayerClassByName(otherName)
                        if otherClass and NP.TANK_CLASSES[otherClass] then
                            threatColor = THREAT_COLORS.TANK.OTHER_TANK
                        else
                            threatColor = THREAT_COLORS.TANK.NO_AGGRO
                        end
                        threatPctValue = otherPct or 0
                    else
                        threatColor = THREAT_COLORS.TANK.NO_AGGRO
                        threatPctValue = otherPct or 0
                    end
                else
                    if playerHasAggro then
                        threatColor = THREAT_COLORS.DPS.AGGRO
                        threatPctValue = 100
                    elseif otherPct and otherPct > 70 then
                        threatColor = THREAT_COLORS.DPS.HIGH_THREAT
                        threatPctValue = otherPct
                    else
                        threatColor = THREAT_COLORS.DPS.NO_AGGRO
                        threatPctValue = otherPct or 0
                    end
                end
            end

            if not hasData and NanamiDPS and NanamiDPS.ThreatEngine then
                local TE = NanamiDPS.ThreatEngine
                if TE.inCombat and unitstr then
                    local data = TE:QueryUnitThreat(unitstr)
                    if not data and plateName then
                        local tk = TE.GetTargetKey and TE.GetTargetKey(unitstr)
                        if tk then
                            local t, isTk, pct = TE:QueryNameThreat(tk, UnitName("player"))
                            if t > 0 then
                                data = { pct = pct, isTanking = isTk, threat = t,
                                         tankThreat = 0, secondPct = 0, secondName = nil }
                            end
                        end
                    end
                    if data then
                        local role = threatPctRole
                        if role == "TANK" then
                            if data.isTanking then
                                threatColor = THREAT_COLORS.TANK.AGGRO
                                threatPctValue = data.secondPct or 0
                            else
                                threatColor = THREAT_COLORS.TANK.NO_AGGRO
                                threatPctValue = data.pct or 0
                            end
                        else
                            if data.isTanking then
                                threatColor = THREAT_COLORS.DPS.AGGRO
                                threatPctValue = 100
                            elseif data.pct and data.pct > 70 then
                                threatColor = THREAT_COLORS.DPS.HIGH_THREAT
                                threatPctValue = data.pct
                            else
                                threatColor = THREAT_COLORS.DPS.NO_AGGRO
                                threatPctValue = data.pct or 0
                            end
                        end
                    end
                end
            end
        end

        -- Stun override
        if unitstr and hasValidGUID then
            for _, stunEffect in ipairs(NP.STUN_EFFECTS) do
                local data = SpellDB and SpellDB:FindEffectData(unitstr, 0, stunEffect)
                if data and data.start and data.duration then
                    if data.start + data.duration > GetTime() then
                        threatColor = THREAT_COLORS.STUN
                        threatPctValue = nil
                        break
                    end
                end
            end
        end

        if threatColor then
            barR, barG, barB = threatColor[1], threatColor[2], threatColor[3]
        end

        if np.threatPctText then
            if threatPctValue and threatColor then
                np.threatPctText:SetText(string.format("%.0f%%", threatPctValue))
                np.threatPctText:SetTextColor(threatColor[1], threatColor[2], threatColor[3], 1)
                np.threatPctText:Show()
            else
                np.threatPctText:SetText("")
                np.threatPctText:Hide()
            end
        end
    else
        if np.threatPctText then
            np.threatPctText:SetText("")
            np.threatPctText:Hide()
        end
    end

    np.health:SetStatusBarColor(barR, barG, barB, 1)

    -- Sync target glow with final bar color (must happen here, not in UpdateTarget,
    -- because the bar color may have changed this frame due to combat/threat)
    if np.targetGlow and np.targetGlow:IsShown() then
        np.targetGlow:SetStatusBarColor(barR, barG, barB, 1)
        local lum = 0.299 * barR + 0.587 * barG + 0.114 * barB
        local glowAlpha = 0.75
        if lum > 0.5 then
            glowAlpha = 0.75 * math.max(0.15, (1.0 - lum) * 2)
        end
        np.targetGlow:SetAlpha(glowAlpha)
    end

    -- Target detection
    local isTarget = false
    if UnitExists("target") then
        if unitstr and hasValidGUID then
            isTarget = UnitIsUnit(unitstr, "target")
        else
            isTarget = (UnitName("target") == plateName) and (not UnitIsFriend("player", "target") == not isFriendly)
        end
    end
    np.isTarget = isTarget

    -- Target nameplate always on top via FrameStrata
    if isTarget and not np._isTargetStrata then
        np._isTargetStrata = true
        np:SetFrameStrata("HIGH")
    elseif not isTarget and np._isTargetStrata then
        np._isTargetStrata = false
        np:SetFrameStrata(np._defaultStrata)
    end

    -- Target highlight
    if NanamiPlates_Target then
        NanamiPlates_Target.UpdateTarget(np, isTarget)
    end

    -- Non-target alpha (only update on change)
    local wantAlpha = (UnitExists("target") and not isTarget) and (Settings.nonTargetAlpha or 0.6) or 1
    if np._lastAlpha ~= wantAlpha then
        np._lastAlpha = wantAlpha
        np:SetAlpha(wantAlpha)
    end

    -- Mana/Energy/Rage bar update (inside healthBG)
    local manaShowing = false
    local manaH = Settings.manabarHeight or 3
    if Settings.showManaBar and unitstr and hasValidGUID and UnitMana and UnitManaMax then
        local manaMax = UnitManaMax(unitstr)
        if manaMax and manaMax > 0 then
            local manaCur = UnitMana(unitstr) or 0
            local powerType = UnitPowerType and UnitPowerType(unitstr) or 0
            local powerColor = Colors.power[powerType] or Colors.power[0]

            if not np.manaBar:IsShown() then
                np.manaBar:SetWidth(hWidth)
                np.manaBar:SetHeight(manaH)
                np.manaBar:Show()
                np.manaSep:Show()
            end
            np.manaBar:SetMinMaxValues(0, manaMax)
            np.manaBar:SetValue(manaCur)
            np.manaBar:SetStatusBarColor(powerColor[1], powerColor[2], powerColor[3], 1)
            manaShowing = true
        end
    end
    if not manaShowing and np.manaBar:IsShown() then
        np.manaBar:Hide()
        np.manaSep:Hide()
    end

    -- Resize healthBG only when mana visibility or style changes
    local needResize = (np._lastManaShowing ~= manaShowing) or (np._lastFriendly_resize ~= isFriendlyStyle)
    if needResize then
        np._lastManaShowing = manaShowing
        np._lastFriendly_resize = isFriendlyStyle
        if manaShowing then
            np.healthBG:SetHeight(hHeight + manaH + 1 + BORDER_PAD * 2)
        else
            np.healthBG:SetHeight(hHeight + BORDER_PAD * 2)
        end
        np.healthBG:SetWidth(hWidth + BORDER_PAD * 2)

        local cbHeight = isFriendlyStyle and (Settings.friendCastbarHeight or 6) or (Settings.castbarHeight or 10)
        np.castbarBG:SetWidth(hWidth + 2)
        np.castbarBG:SetHeight(cbHeight + 2)
    end

    local castShowing = false
    local casting = nil
    local castNow = GetTime()

    -- Method 1: castDB by GUID (UNIT_CASTEVENT, unitstr IS the GUID from GetName(1))
    local castDB = NP.castDB
    if hasValidGUID and unitstr and castDB[unitstr] then
        local cast = castDB[unitstr]
        if cast.startTime + (cast.duration / 1000) > castNow then
            casting = cast
        else
            castDB[unitstr] = nil
        end
    end

    -- Method 2: UnitCastingInfo / UnitChannelInfo (SuperWoW 1.5+)
    if not casting and superwow_active and hasValidGUID and unitstr then
        if UnitCastingInfo then
            local spell, _, _, texture, startTime, endTime = UnitCastingInfo(unitstr)
            if spell then
                casting = {
                    spell = spell,
                    startTime = startTime / 1000,
                    duration = endTime - startTime,
                    icon = texture
                }
            end
        end
        if not casting and UnitChannelInfo then
            local spell, _, _, texture, startTime, endTime = UnitChannelInfo(unitstr)
            if spell then
                casting = {
                    spell = spell,
                    startTime = startTime / 1000,
                    duration = endTime - startTime,
                    icon = texture,
                    channel = true
                }
            end
        end
    end

    -- Method 3: Fallback to original Blizzard castbar visibility
    if not casting and original.castbar then
        local origCBVisible = original.castbar.IsVisible and original.castbar:IsVisible()
        if not origCBVisible then
            origCBVisible = original.castbar.IsShown and original.castbar:IsShown()
        end
        if origCBVisible then
            local castVal = original.castbar:GetValue() or 0
            local castMin, castMax = original.castbar:GetMinMaxValues()
            if castMax and castMax > 0 then
                np.castbar:SetMinMaxValues(castMin, castMax)
                np.castbar:SetValue(castVal)
                np.castbarText:SetText("")
                np.castbarTimer:SetText("")
                np.castbarIcon:Hide()
                np.castbarBG:Show()
                castShowing = true
            end
        end
    end

    -- Render castbar from Method 1 or 2
    if casting and casting.spell and not castShowing then
        local start = casting.startTime
        local duration = casting.duration
        if castNow < start + (duration / 1000) then
            np.castbar:SetMinMaxValues(0, duration)
            if casting.channel then
                np.castbar:SetValue(duration - (castNow - start) * 1000)
            else
                np.castbar:SetValue((castNow - start) * 1000)
            end
            np.castbarText:SetText(casting.spell)
            local timeLeft = (start + (duration / 1000)) - castNow
            np.castbarTimer:SetText(string_format("%.1f", timeLeft))

            if casting.icon then
                np.castbarIcon:SetTexture(casting.icon)
                np.castbarIcon:Show()
            else
                np.castbarIcon:Hide()
            end

            np.castbarBG:Show()
            castShowing = true
        end
    end

    if not castShowing then
        np.castbarBG:Hide()
        np.castbarIcon:Hide()
    end

    -- Debuff update (throttled)
    local now = GetTime()
    if now - np.lastDebuffUpdate >= DEBUFF_UPDATE_INTERVAL then
        np.lastDebuffUpdate = now
        local numDebuffs = 0

        -- Debuff anchor: below castbar if visible, else below healthBG (which now includes mana)
        if castShowing then
            np.debuffAnchor = np.castbarBG
        else
            np.debuffAnchor = np.healthBG
        end

        if NanamiPlates_Auras and np.debuffs then
            numDebuffs = NanamiPlates_Auras:UpdateDebuffs(np, unitstr, plateName, isTarget, hasValidGUID, superwow_active)
            NanamiPlates_Auras:UpdateDebuffPositions(np, numDebuffs)
        end

        -- Combo points
        if NanamiPlates_ComboPoints then
            local numPoints = NanamiPlates_ComboPoints:UpdateComboPoints(np, isTarget)
            NanamiPlates_ComboPoints:UpdateComboPointPositions(np, numDebuffs)
        end
    end
end

-- Nameplate vertical stacking resolution
-- Engine anti-overlap is fully disabled (parent set to 1x1 like ShaguPlates),
-- so we resolve overlaps ourselves with a stable algorithm.
local stackPool = {}
local stackN = 0
local STACK_SMOOTH = 0.15

local function ResolveStacking()
    if not Settings.enableStacking then
        -- Stacking disabled: decay any residual offsets from when it was enabled
        for frame, np in pairs(registry) do
            if np._stackY and np._stackY ~= 0 then
                local new = np._stackY * (1 - STACK_SMOOTH * 3)
                if new > -0.5 and new < 0.5 then new = 0 end
                np._stackY = new
                np._appliedOffY = (Settings.nameplateYOffset or 0) + new
                np.healthBG:ClearAllPoints()
                np.healthBG:SetPoint("CENTER", np, "CENTER", 0, np._appliedOffY)
            end
        end
        return
    end

    stackN = 0
    for frame, np in pairs(registry) do
        if frame:IsShown() and np:IsShown() then
            local cx, cy = frame:GetCenter()
            if cx and cy then
                stackN = stackN + 1
                if not stackPool[stackN] then stackPool[stackN] = {} end
                local e = stackPool[stackN]
                e.np = np
                e.cx = cx
                e.cy = cy
                e.name = np.plateName or ""
                e.stackTarget = 0
            end
        end
    end

    if stackN < 1 then return end

    -- Single plate: decay any residual stacking offset
    if stackN < 2 then
        local np = stackPool[1].np
        if np._stackY and np._stackY ~= 0 then
            local new = np._stackY * (1 - STACK_SMOOTH * 3)
            if new > -0.5 and new < 0.5 then new = 0 end
            np._stackY = new
            np._appliedOffY = (Settings.nameplateYOffset or 0) + new
            np.healthBG:ClearAllPoints()
            np.healthBG:SetPoint("CENTER", np, "CENTER", 0, np._appliedOffY)
        end
        return
    end

    -- Stable bubble sort: Y descending (higher on screen first), name as tiebreaker
    for i = stackN, 2, -1 do
        for j = 1, i - 1 do
            local a = stackPool[j]
            local b = stackPool[j + 1]
            local ay = math_floor(a.cy)
            local by = math_floor(b.cy)
            if by > ay or (by == ay and b.name < a.name) then
                stackPool[j] = b
                stackPool[j + 1] = a
            end
        end
    end

    -- Resolve vertical overlaps: push lower plates down when horizontally close
    local minSep = (Settings.healthbarHeight or 12) + BORDER_PAD * 2
        + (Settings.nameFontSize or 9) + 6
    local overlapW = (Settings.healthbarWidth or 120) * 0.8

    for i = 1, stackN do
        for j = i + 1, stackN do
            local a = stackPool[i]
            local b = stackPool[j]
            local dx = a.cx - b.cx
            if dx < 0 then dx = -dx end
            if dx < overlapW then
                local ya = a.cy + a.stackTarget
                local yb = b.cy + b.stackTarget
                local gap = ya - yb
                if gap < minSep then
                    b.stackTarget = b.stackTarget - (minSep - gap)
                end
            end
        end
    end

    -- Apply stacking offsets with smooth convergence
    for i = 1, stackN do
        local e = stackPool[i]
        local np = e.np

        local curStack = np._stackY or 0
        local tarStack = e.stackTarget
        local d = tarStack - curStack
        local newStack
        if d > -0.5 and d < 0.5 then
            newStack = tarStack
        else
            newStack = curStack + d * STACK_SMOOTH
        end
        if newStack > -0.3 and newStack < 0.3 then newStack = 0 end
        np._stackY = newStack

        local offY = (Settings.nameplateYOffset or 0) + newStack

        local pY = np._appliedOffY or (Settings.nameplateYOffset or 0)
        if (offY - pY) > 0.5 or (offY - pY) < -0.5 then
            np._appliedOffY = offY
            np.healthBG:ClearAllPoints()
            np.healthBG:SetPoint("CENTER", np, "CENTER", 0, offY)
        end
    end
end

-- Main OnUpdate loop
local scanThrottle = 0
local SCAN_INTERVAL = 0.1

local function OnUpdate()
    local now = GetTime()

    -- Rebuild quest mob cache periodically
    if now - questCacheTimer >= QUEST_CACHE_INTERVAL then
        questCacheTimer = now
        RebuildQuestMobCache()
    end

    -- Scan for new nameplates
    if now - scanThrottle >= SCAN_INTERVAL then
        scanThrottle = now
        Scanner.ScanForNewNameplates(registry, HandleNamePlate)
    end

    -- Update all active nameplates
    for frame, np in pairs(registry) do
        if frame:IsShown() then
            UpdateNamePlate(frame)
        end
    end

    -- Resolve stacking overlaps and smooth position jitter
    ResolveStacking()

    -- Cleanup debuff timers
    if NanamiPlates_Auras then
        NanamiPlates_Auras:CleanupTimers()
    end
end

-- Event handler
local function OnEvent()
    local evnt = event

    if evnt == "ADDON_LOADED" and arg1 == "Nanami-Plates" then
        NP:LoadSettings()
        NP.Print("Loaded.")

    elseif evnt == "PLAYER_ENTERING_WORLD" then
        Scanner.Reset()
        if NanamiPlates_Castbar.ClearCastData then
            NanamiPlates_Castbar.ClearCastData()
        end
        NP.playerClassCache = {}

        if SpellDB and SpellDB.ScanSpellbook then
            SpellDB:ScanSpellbook()
        end

        NP:DetectTankSpec()

        if NanamiPlates_Threat then
            NanamiPlates_Threat.BroadcastTankMode(true)
        end

    elseif evnt == "CHARACTER_POINTS_CHANGED" then
        NP:DetectTankSpec()

    elseif evnt == "UNIT_CASTEVENT" then
        if superwow_active and arg1 then
            NanamiPlates_Castbar.HandleUnitCastEvent(arg1, arg2, arg3, arg4, arg5)
        end

    elseif evnt == "SPELLCAST_STOP" then
        if SpellDB then SpellDB:PersistPending() end

    elseif evnt == "CHAT_MSG_SPELL_FAILED_LOCALPLAYER" then
        if SpellDB then SpellDB:RemovePending() end

    elseif evnt == "QUEST_LOG_UPDATE" then
        questCacheTimer = 0

    elseif evnt == "PLAYER_TARGET_CHANGED" then
        -- Force debuff update on all plates
        for frame, np in pairs(registry) do
            if frame:IsShown() then
                np.lastDebuffUpdate = 0
            end
        end

    elseif evnt == "PLAYER_REGEN_DISABLED" then
        playerInCombat = true

    elseif evnt == "PLAYER_REGEN_ENABLED" then
        playerInCombat = false
        NP.playerClassCache = {}
        if SpellDB then
            for k in pairs(SpellDB.objects) do
                SpellDB.objects[k] = nil
            end
        end

    elseif evnt == "PARTY_MEMBERS_CHANGED" or evnt == "RAID_ROSTER_UPDATE" then
        NP.playerClassCache = {}
        if NanamiPlates_Threat then
            NanamiPlates_Threat.BroadcastTankMode(true)
        end

    elseif NP.SPELL_EVENTS[evnt] then
        if NanamiPlates_CombatLog then
            NanamiPlates_CombatLog.HandleSpellEvent(evnt, arg1)
        end

    elseif NP.COMBAT_EVENTS[evnt] then
        if NanamiPlates_CombatLog then
            NanamiPlates_CombatLog.HandleCombatEvent(evnt, arg1)
        end
    end
end

NP.EventFrame:SetScript("OnEvent", OnEvent)
NP.EventFrame:SetScript("OnUpdate", OnUpdate)