---@type Orbit
local Orbit = Orbit
local OrbitEngine = Orbit.Engine
local LSM = LibStub("LibSharedMedia-3.0")
local GC = Orbit.Engine.GlowController

Orbit.GroupFramePreviewMixin = {}

-- [ CONSTANTS ]-------------------------------------------------------------------------------------
local Helpers = Orbit.GroupFrameHelpers
local MAX_PARTY_PREVIEW = 5
local PREVIEW_GROUPS = 4
local DEBOUNCE_DELAY = Orbit.Constants.Timing.DefaultDebounce

local GF = Orbit.Constants.GroupFrames
local OFFLINE_ALPHA = GF.OfflineAlpha
local ROLE_PRIORITY = GF.RolePriority

local PARTY_PRIVATE_AURA_ICON_SIZE = 24
local PARTY_HEALER_AURA_ICON_SIZE = 16
local RAID_PRIVATE_AURA_ICON_SIZE = 18
local RAID_HEALER_AURA_ICON_SIZE = 12
local RAID_STATUS_ICON_SIZE = 18
local HealerReg = Orbit.HealerAuraRegistry

local SafeRegisterUnitWatch = Orbit.GroupFrameMixin.SafeRegisterUnitWatch
local SafeUnregisterUnitWatch = Orbit.GroupFrameMixin.SafeUnregisterUnitWatch

local ApplyIconPosition = function(icon, parentFrame, pos)
    OrbitEngine.PositionUtils.ApplyIconPosition(icon, parentFrame, pos)
end

-- [ PREVIEW DATA ] ----------------------------------------------------------------------------------
local TIER_COMP = {
    Party  = { tanks = 1, healers = 1, dps = 3  },
    Mythic = { tanks = 2, healers = 4, dps = 14 },
    Heroic = { tanks = 2, healers = 6, dps = 22 },
    World  = { tanks = 4, healers = 8, dps = 28 },
}

-- Parallel-indexed with Orbit.PlayerDummies; kept local because health% is GroupFrames-specific.
local HEALTH_PCTS = {
    100, 85, 60, 40, 95, 75, 90, 50, 80, 70,
    65, 100, 88, 55, 72, 92, 78, 83, 95, 100,
    68, 91, 45, 82, 77, 53, 99, 62, 86, 74,
    58, 93, 71, 48, 87, 96, 64, 79, 100, 85,
    73, 66, 89, 42, 97,
}

-- [ CANVAS MODE DETECTION ]-------------------------------------------------------------------------
local function IsCanvasModeActive(plugin)
    if OrbitEngine and OrbitEngine.CanvasMode and OrbitEngine.CanvasMode.currentFrame then
        local dl = OrbitEngine.CanvasModeDialog or (Orbit and Orbit.CanvasModeDialog)
        if dl and not dl:IsShown() then return false end
        if OrbitEngine.CanvasMode.currentFrame == plugin.container then return true end
        for _, frame in ipairs(plugin.frames) do
            if OrbitEngine.CanvasMode.currentFrame == frame then return true end
        end
    end
    return false
end

-- [ PREVIEW SORT ORDER ]----------------------------------------------------------------------------
local function GetPreviewSortOrder(plugin)
    local tier = plugin:GetCurrentTier()
    local comp = TIER_COMP[tier] or TIER_COMP.Mythic
    local roster = Orbit.PlayerDummies

    if not plugin._previewRosterTier or plugin._previewRosterTier ~= tier then
        plugin._previewRosterTanks   = roster:ShuffleIndices("TANK")
        plugin._previewRosterHealers = roster:ShuffleIndices("HEALER")
        plugin._previewRosterDPS     = roster:ShuffleIndices("DAMAGER")
        plugin._previewRosterTier    = tier
    end

    local order = {}
    for i = 1, comp.tanks do order[#order + 1] = plugin._previewRosterTanks[i] end
    for i = 1, comp.healers do order[#order + 1] = plugin._previewRosterHealers[i] end
    for i = 1, comp.dps do order[#order + 1] = plugin._previewRosterDPS[i] end

    local sortMode = plugin:GetTierSetting("SortMode") or "group"
    if sortMode == "role" then
        table.sort(order, function(a, b)
            local pa = ROLE_PRIORITY[roster[a] and roster[a].role] or 4
            local pb = ROLE_PRIORITY[roster[b] and roster[b].role] or 4
            if pa ~= pb then return pa < pb end
            return ((roster[a] and roster[a].name) or "") < ((roster[b] and roster[b].name) or "")
        end)
    elseif sortMode == "alphabetical" then
        table.sort(order, function(a, b)
            return ((roster[a] and roster[a].name) or "") < ((roster[b] and roster[b].name) or "")
        end)
    end
    return order
end

-- [ SHOW PREVIEW ]----------------------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:ShowPreview()
    if InCombatLockdown() or not self.frames or not self.container then return end


    UnregisterStateDriver(self.container, "visibility")
    self.container:Show()

    local isCanvasMode = IsCanvasModeActive(self)
    local isParty = self:IsPartyTier()

    local currentTier = self:GetCurrentTier()
    local comp = TIER_COMP[currentTier] or TIER_COMP.Mythic
    local framesToShow
    if isCanvasMode then
        framesToShow = 1
    elseif isParty then
        local includePlayer = self:GetTierSetting("IncludePlayer")
        framesToShow = includePlayer and 5 or 4
    else
        framesToShow = comp.tanks + comp.healers + comp.dps
    end

    local maxFrames = Helpers.LAYOUT.MaxGroupFrames
    for i = 1, maxFrames do
        local frame = self.frames[i]
        if frame then
            SafeUnregisterUnitWatch(frame)
            if frame.SetAttribute then frame:SetAttribute("unit", nil) end
            frame.unit = nil
            if i <= framesToShow then
                frame.preview = true
                frame:Show()
            else
                frame.preview = nil
                frame:Hide()
            end
        end
    end

    self:PositionFrames()
    self:UpdateContainerSize()
    OrbitEngine.FrameSelection:ForceUpdate(self.container)

    C_Timer.After(DEBOUNCE_DELAY, function()
        if self.frames then
            self:ApplyPreviewVisuals()
            if not isCanvasMode then self:StartPreviewAnimation() end
        end
    end)

    Orbit.PreviewAnimator:WatchCanvas(self)
end

-- [ APPLY PREVIEW VISUALS ]-------------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:ApplyPreviewVisuals()
    if not self.frames then return end

    local isCanvasMode = IsCanvasModeActive(self)
    local isParty = self:IsPartyTier()
    local roster = Orbit.PlayerDummies
    local sortOrder = GetPreviewSortOrder(self)
    local componentPositions = self:GetComponentPositions(1)
    local isDisabled = self.IsComponentDisabled and function(key) return self:IsComponentDisabled(key) end or function() return false end
    local roleAtlases = Orbit.RoleAtlases

    local currentTier = self:GetCurrentTier()
    local comp = TIER_COMP[currentTier] or TIER_COMP.Mythic
    local maxPreview
    if isCanvasMode then
        maxPreview = 1
    elseif isParty then
        local includePlayer = self:GetTierSetting("IncludePlayer")
        maxPreview = includePlayer and 5 or 4
    else
        maxPreview = comp.tanks + comp.healers + comp.dps
    end
    local showPower = self:GetTierSetting("ShowPowerBar")
    if showPower == nil then showPower = true end

    for i = 1, maxPreview do
        local frame = self.frames[i]
        if frame and frame.preview then
            local dataIdx = sortOrder and sortOrder[i] or i
            local entry = roster[dataIdx] or {}
            local role = entry.role
            local isHealer = role == "HEALER"
            local showThisPower = isParty and (showPower or isHealer) or (showPower and isHealer)

            -- Shared styling (size, border, texture, text, positions)
            self:ApplyFrameStyle(frame, showThisPower)

            -- Preview backdrop
            if self.ApplyPreviewBackdrop then self:ApplyPreviewBackdrop(frame)
            elseif self.CreateBackground then
                self:CreateBackground(frame)
                local globalSettings = Orbit.db.GlobalSettings or {}
                Orbit.Skin:ApplyGradientBackground(frame, globalSettings.UnitFrameBackdropColourCurve, Orbit.Constants.Colors.Background)
            end

            -- Health bar
            if frame.Health then
                frame.Health:SetMinMaxValues(0, 100)
                frame.Health:SetValue(100)
                frame:ApplyPreviewHealthColor(entry.classFilename)
                frame.Health:Show()
                if frame.HealthDamageBar then frame.HealthDamageBar:Hide() end
                if frame.HealthDamageTexture then frame.HealthDamageTexture:Hide() end
            end

            -- Power bar
            if frame.Power and showThisPower then
                frame.Power:SetMinMaxValues(0, 100)
                frame.Power:SetValue(100)
                frame.Power:SetStatusBarColor(0, 0.5, 1)
            end

            -- Name
            if frame.Name then
                if isDisabled("Name") then frame.Name:Hide()
                else
                    frame._fullName = entry.name
                    frame.Name:SetText(entry.name)
                    frame.Name:SetTextColor(1, 1, 1, 1)
                    frame.Name:Show()
                end
            end

            -- Health text
            if frame.HealthText then
                local showHealthValue = self:GetTierSetting("ShowHealthValue")
                if showHealthValue == nil then showHealthValue = true end
                if isDisabled("HealthText") or not showHealthValue then frame.HealthText:Hide()
                else
                    frame.HealthText:SetText("100%")
                    frame.HealthText:SetTextColor(1, 1, 1, 1)
                    frame.HealthText:Show()
                end
            end

            frame:SetAlpha(1)
            frame.previewClassFile = entry.classFilename

            -- Role icon
            if frame.RoleIcon then
                if isDisabled("RoleIcon") then frame.RoleIcon:Hide()
                else
                    local roleOverrides = componentPositions.RoleIcon and componentPositions.RoleIcon.overrides
                    local hideDPS = roleOverrides and roleOverrides.HideDPS
                    local activeAtlases = roleAtlases
                    local style = roleOverrides and roleOverrides.RoleIconStyle
                    if style == "round" then
                        activeAtlases = { TANK = "icons_64x64_tank", HEALER = "icons_64x64_heal", DAMAGER = "icons_64x64_damage" }
                    elseif style == "header" then
                        activeAtlases = { TANK = "GO-icon-role-Header-Tank", HEALER = "GO-icon-role-Header-Healer", DAMAGER = "GO-icon-role-Header-DPS", DAMAGER_RANGED = "GO-icon-role-Header-DPS-Ranged" }
                    end
                    -- Resolve ranged DPS for header style preview (pure ranged DPS classes)
                    local resolvedRole = role
                    if role == "DAMAGER" and activeAtlases.DAMAGER_RANGED then
                        local cls = entry.classFilename
                        if cls == "HUNTER" or cls == "MAGE" or cls == "WARLOCK" or cls == "EVOKER" then resolvedRole = "DAMAGER_RANGED" end
                    end
                    if role == "DAMAGER" and hideDPS then frame.RoleIcon:Hide()
                    elseif activeAtlases[resolvedRole] then
                        frame.RoleIcon:SetAtlas(activeAtlases[resolvedRole])
                        frame.RoleIcon:Show()
                        if componentPositions.RoleIcon then ApplyIconPosition(frame.RoleIcon, frame, componentPositions.RoleIcon) end
                    else frame.RoleIcon:Hide() end
                end
            end

            -- Leader icon
            if frame.LeaderIcon then
                if isDisabled("LeaderIcon") then frame.LeaderIcon:Hide()
                elseif i == 1 then
                    local leaderOverrides = componentPositions.LeaderIcon and componentPositions.LeaderIcon.overrides
                    local leaderAtlas = (leaderOverrides and leaderOverrides.LeaderIconStyle == "header")
                        and "GO-icon-Header-Assist-Applied"
                        or (Orbit.IconPreviewAtlases and Orbit.IconPreviewAtlases.LeaderIcon or "UI-HUD-UnitFrame-Player-Group-LeaderIcon")
                    frame.LeaderIcon:SetTexture(nil)
                    frame.LeaderIcon:SetTexCoord(0, 1, 0, 1)
                    frame.LeaderIcon:SetAtlas(leaderAtlas)
                    frame.LeaderIcon:Show()
                    if componentPositions.LeaderIcon then ApplyIconPosition(frame.LeaderIcon, frame, componentPositions.LeaderIcon) end
                else frame.LeaderIcon:Hide() end
            end

            -- MainTankIcon (raid tiers only)
            if frame.MainTankIcon then
                if isParty or isDisabled("MainTankIcon") then frame.MainTankIcon:Hide()
                elseif isCanvasMode or (role == "TANK" and i <= 2) then
                    frame.MainTankIcon:SetAtlas(i == 1 and "RaidFrame-Icon-MainTank" or "RaidFrame-Icon-MainAssist")
                    frame.MainTankIcon:Show()
                    if componentPositions.MainTankIcon then ApplyIconPosition(frame.MainTankIcon, frame, componentPositions.MainTankIcon) end
                else frame.MainTankIcon:Hide() end
            end

            -- Selection/Aggro highlights
            if i == 2 then 
                local rawSelection = self:GetTierSetting("SelectionColor") or { r = 0.8, g = 0.9, b = 1.0, a = 1 }
                local selColor = (Orbit.Engine.ColorCurve and Orbit.Engine.ColorCurve:GetFirstColorFromCurve(rawSelection) or rawSelection)
                Orbit.Skin:ApplyHighlightBorder(frame, "_selectionBorderOverlay", selColor, Orbit.Constants.Levels.Border + 1, "ADD")
            else Orbit.Skin:ClearHighlightBorder(frame, "_selectionBorderOverlay") end
            if i == 2 then 
                local rawAggro = self:GetTierSetting("AggroColor") or { r = 1.0, g = 0.0, b = 0.0, a = 1 }
                local aggroColor = (Orbit.Engine.ColorCurve and Orbit.Engine.ColorCurve:GetFirstColorFromCurve(rawAggro) or rawAggro)
                Orbit.Skin:ApplyHighlightBorder(frame, "_aggroHighlightOverlay", aggroColor, Orbit.Constants.Levels.Border + 2)
            else Orbit.Skin:ClearHighlightBorder(frame, "_aggroHighlightOverlay") end

            -- Canvas Mode icons
            local privateAuraSize = isParty and PARTY_PRIVATE_AURA_ICON_SIZE or RAID_PRIVATE_AURA_ICON_SIZE
            local healerAuraSize = isParty and PARTY_HEALER_AURA_ICON_SIZE or RAID_HEALER_AURA_ICON_SIZE
            local statusIconSize = isParty and 24 or RAID_STATUS_ICON_SIZE
            local statusIcons = { "PhaseIcon", "ReadyCheckIcon", "ResIcon", "SummonIcon" }
            local hideKeys = not isParty and { "PhaseIcon", "ReadyCheckIcon", "ResIcon", "SummonIcon", "DefensiveIcon", "CrowdControlIcon", "PrivateAuraAnchor", "MainTankIcon" } or nil
            Orbit.GroupCanvasRegistration:ShowCanvasModeIcons(self, frame, isCanvasMode, {
                statusIcons = statusIcons,
                statusIconSize = statusIconSize, statusIconSpacing = statusIconSize + 4,
                privateAuraSize = privateAuraSize,
                healerAuraSize = healerAuraSize,
                hideKeys = hideKeys,
            }, HealerReg:ActiveSlots(), HealerReg:ActiveRaidBuffs(), HealerReg:ActiveKeys())

            -- Auras
            if isCanvasMode then self:ShowPreviewAuras(frame, i)
            else Orbit.AuraPreview:HideFrameAuras(frame) end

            GC:Hide(frame, "preview")
        end
    end
end

-- [ PREVIEW AURAS ]---------------------------------------------------------------------------------
local GROUP_PREVIEW_AURA_CFG = {
    helpers = function() return Orbit.GroupFrameHelpers end,
    defaultAnchorX = "RIGHT", defaultJustifyH = "LEFT",
    defaultMax = 3,
}
local GROUP_PREVIEW_BUFF_CFG = {
    helpers = function() return Orbit.GroupFrameHelpers end,
    defaultAnchorX = "LEFT", defaultJustifyH = "RIGHT",
    defaultMax = 3,
}

function Orbit.GroupFramePreviewMixin:ShowPreviewAuras(frame, frameIndex)
    Orbit.AuraPreview:ShowFrameAuras(self, frame, GROUP_PREVIEW_AURA_CFG, GROUP_PREVIEW_BUFF_CFG)
end

-- [ HIDE PREVIEW ]----------------------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:HidePreview()
    if InCombatLockdown() or not self.frames then return end

    self._editTierOverride = nil
    self._previewRosterTier = nil

    Orbit.PreviewAnimator:Stop(self)
    Orbit.PreviewAnimator:StopAuras(self)
    Orbit.PreviewAnimator:StopHealerAuras(self)
    if Orbit.PreviewAnimator.StopDispels then Orbit.PreviewAnimator:StopDispels(self) end
    Orbit.PreviewAnimator:UnwatchCanvas(self)

    local maxFrames = Helpers.LAYOUT.MaxGroupFrames
    for i = 1, maxFrames do
        local frame = self.frames[i]
        if frame then
            frame.preview = nil
            frame:SetAlpha(1)
            frame:EnableMouse(true)
            frame:SetAttribute("unit", nil)
            frame.unit = nil
            frame:Hide()
            if frame.previewDebuffs then
                for _, icon in ipairs(frame.previewDebuffs) do icon:Hide() end
                wipe(frame.previewDebuffs)
            end
            if frame.previewBuffs then
                for _, icon in ipairs(frame.previewBuffs) do icon:Hide() end
                wipe(frame.previewBuffs)
            end
            if frame._privateAuraIDs then
                for _, id in ipairs(frame._privateAuraIDs) do C_UnitAuras.RemovePrivateAuraAnchor(id) end
                wipe(frame._privateAuraIDs)
            end
            local paa = frame.PrivateAuraAnchor
            if paa then
                if paa._previewIcons then for _, sub in ipairs(paa._previewIcons) do sub:Hide() end end
                paa:Hide()
            end
            GC:Hide(frame, "preview")
            for _, key in ipairs(HealerReg:ActiveKeys()) do
                if frame[key] then frame[key]:Hide() end
            end
            if frame.HealthDamageBar then frame.HealthDamageBar:Show() end
            if frame.HealthDamageTexture then frame.HealthDamageTexture:Show() end
        end
    end

    self:UpdateFrameUnits()
    if self.ApplySettings then self:ApplySettings() end
    self:UpdateContainerSize()
end

-- [ SCHEDULE PREVIEW UPDATE ]-----------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:SchedulePreviewUpdate()
    if not self._previewVisualsScheduled then
        self._previewVisualsScheduled = true
        C_Timer.After(DEBOUNCE_DELAY, function()
            self._previewVisualsScheduled = false
            if self.frames then
                self:ApplyPreviewVisuals()
                self:PositionFrames()
                self:UpdateContainerSize()
            end
        end)
    end
end

-- [ PREVIEW BACKDROP ]------------------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:ApplyPreviewBackdrop(frame)
    if not frame then return end
    if self.CreateBackground then self:CreateBackground(frame) end
    local globalSettings = Orbit.db.GlobalSettings or {}
    Orbit.Skin:ApplyGradientBackground(frame, globalSettings.UnitFrameBackdropColourCurve, Orbit.Constants.Colors.Background)
end

-- [ PREVIEW ANIMATION ]-----------------------------------------------------------------------------
function Orbit.GroupFramePreviewMixin:StartPreviewAnimation()
    if not self.frames then return end
    local isParty = self:IsPartyTier()
    local isCanvasMode = IsCanvasModeActive(self)
    local currentTier = self:GetCurrentTier()
    local comp = TIER_COMP[currentTier] or TIER_COMP.Mythic
    local sortOrder = GetPreviewSortOrder(self)
    local healerSlots = HealerReg:ActiveSlots()
    local isDisabled = self.IsComponentDisabled and function(k) return self:IsComponentDisabled(k) end or function() return false end
    local enabledSlots = {}
    for _, slot in ipairs(healerSlots) do
        if not isDisabled(slot.key) then enabledSlots[#enabledSlots + 1] = slot end
    end

    local maxPreview
    if isCanvasMode then
        maxPreview = 1
    elseif isParty then
        local includePlayer = self:GetTierSetting("IncludePlayer")
        maxPreview = includePlayer and 5 or 4
    else
        maxPreview = comp.tanks + comp.healers + comp.dps
    end

    local visibleFrames = {}
    for i = 1, maxPreview do
        local f = self.frames[i]
        if f and f.preview and f:IsShown() then visibleFrames[#visibleFrames + 1] = f end
    end

    local animConfig = {
        frames = visibleFrames,
        getHelpers = function() return Orbit.GroupFrameHelpers end,
        getHealth = function(i)
            local idx = sortOrder and sortOrder[i] or i
            return (HEALTH_PCTS[idx] or 75) / 100
        end,
        getDead = function() return false end,
        healerSlots = enabledSlots,
        raidBuffKey = not isDisabled("RaidBuff") and "RaidBuff" or nil,
    }

    -- Dispel preview for raid tiers
    if not isParty then
        local dispelEnabled = self:GetTierSetting("DispelIndicatorEnabled")
        if dispelEnabled then
            animConfig.dispelSettings = {
                thickness = self:GetTierSetting("DispelThickness") or 2,
                frequency = self:GetTierSetting("DispelFrequency") or 0.25,
                numLines = self:GetTierSetting("DispelNumLines") or 8,
                length = self:GetTierSetting("DispelLength") or 15,
                border = self:GetTierSetting("DispelBorder") ~= false,
                glowType = self:GetTierSetting("DispelGlowType") or Orbit.Constants.Glow.Type.Pixel,
                colors = {
                    Magic = self:GetTierSetting("DispelColorMagic") or { r = 0.2, g = 0.6, b = 1.0, a = 1 },
                    Curse = self:GetTierSetting("DispelColorCurse") or { r = 0.6, g = 0.0, b = 1.0, a = 1 },
                    Disease = self:GetTierSetting("DispelColorDisease") or { r = 0.6, g = 0.4, b = 0.0, a = 1 },
                    Poison = self:GetTierSetting("DispelColorPoison") or { r = 0.0, g = 0.6, b = 0.0, a = 1 },
                },
            }
        end
    end

    Orbit.PreviewAnimator:StartAll(self, animConfig)
end
