local E, L, V, P, G = unpack(ElvUI)
local UF = E:GetModule("UnitFrames")

--Lua functions
local _G = _G
local pairs = pairs
local select = select
local assert = assert
local tinsert = tinsert
--WoW API / Variables
local CreateFrame = CreateFrame
local UnitClass = UnitClass
local UnitExists = UnitExists
local UnitIsPlayer = UnitIsPlayer
local UnitIsUnit = UnitIsUnit
local UnitReaction = UnitReaction

function UF:FrameGlow_MouseOnUnit(frame)
	if frame and frame:IsVisible() and UnitExists("mouseover") then
		local unit = frame.unit or (frame.isForced and "player")
		return unit and UnitIsUnit("mouseover", unit)
	end

	return false
end

function UF:FrameGlow_ElementHook(frame, glow, which)
	if not (frame and frame.__elements) then return end
	tinsert(frame.__elements, function()
		local unit = frame.unit or (frame.isForced and "player")
		if unit then
			UF:FrameGlow_SetGlowColor(glow, unit, which)
		end

		if which == "mouseoverGlow" then
			UF:FrameGlow_Position(frame)
			UF:FrameGlow_CheckMouseover(frame)
		else
			UF:FrameGlow_PositionGlow(frame, glow, glow.powerGlow)
		end

		if which == "targetGlow" then
			UF:FrameGlow_CheckTarget(frame)
		end
	end)
end

function UF:FrameGlow_HookPowerBar(frame, power, powerName, glow, offset)
	if (frame and power and powerName and glow and offset) and not glow[powerName.."Hooked"] then
		glow[powerName.."Hooked"] = true
		local func = function() UF:FrameGlow_ClassGlowPosition(frame, powerName, glow, offset, true) end
		power:HookScript("OnShow", func)
		power:HookScript("OnHide", func)
	end
end

function UF:FrameGlow_ClassGlowPosition(frame, powerName, glow, offset, fromScript)
	if not (frame and glow and offset) then return end

	local power = powerName and frame[powerName]
	if not power then return end

	if not fromScript then
		UF:FrameGlow_HookPowerBar(frame, power, powerName, glow, offset)
	end

	local portrait = (frame.USE_PORTRAIT and not frame.USE_PORTRAIT_OVERLAY) and (frame.Portrait and frame.Portrait.backdrop)

	if powerName == "HappinessIndicator" and (power and power.backdrop and power:IsVisible()) then
		if frame.ORIENTATION == "RIGHT" then
			glow:Point("TOPLEFT", power.backdrop, -offset, offset)
			glow:Point("TOPRIGHT", portrait or frame.Health.backdrop, offset, offset)
		else
			glow:Point("TOPLEFT", portrait or frame.Health.backdrop, -offset, offset)
			glow:Point("TOPRIGHT", power.backdrop, offset, offset)
		end
	else
		if (power and power.backdrop and power:IsVisible()) and (not (frame.CLASSBAR_DETACHED or frame.USE_MINI_CLASSBAR)) then
			glow:Point("TOPLEFT", (frame.ORIENTATION == "LEFT" and portrait) or power.backdrop, -offset, offset)
			glow:Point("TOPRIGHT", (frame.ORIENTATION == "RIGHT" and portrait) or power.backdrop, offset, offset)
		elseif frame.Health and frame.Health.backdrop then
			glow:Point("TOPLEFT", (frame.ORIENTATION == "LEFT" and portrait) or frame.Health.backdrop, -offset, offset)
			glow:Point("TOPRIGHT", (frame.ORIENTATION == "RIGHT" and portrait) or frame.Health.backdrop, offset, offset)
		end
	end
end

function UF:FrameGlow_PositionGlow(frame, mainGlow, powerGlow)
	if not (frame and frame.VARIABLES_SET) then return end

	local additionalPower = frame.AdditionalPower
	local runes = frame.Runes
	local comboPoints = frame.ComboPoints
	local happiness = frame.HappinessIndicator
	local power = frame.Power and frame.Power.backdrop
	local health = frame.Health and frame.Health.backdrop
	local portrait = (frame.USE_PORTRAIT and not frame.USE_PORTRAIT_OVERLAY) and (frame.Portrait and frame.Portrait.backdrop)
	local offset = (E.PixelMode and 3) or 4 -- edgeSize is 3

	mainGlow:ClearAllPoints()
	mainGlow:Point("TOPLEFT", (frame.ORIENTATION == "LEFT" and portrait) or health, -offset, offset)
	mainGlow:Point("TOPRIGHT", (frame.ORIENTATION == "RIGHT" and portrait) or health, offset, offset)

	if frame.USE_POWERBAR_OFFSET or frame.USE_MINI_POWERBAR then
		mainGlow:Point("BOTTOMLEFT", health, -offset, -offset)
		mainGlow:Point("BOTTOMRIGHT", health, offset, -offset)
	else
		--offset is set because its one pixel off for some reason
		mainGlow:Point("BOTTOMLEFT", frame, -offset, -(E.PixelMode and offset or offset-1))
		mainGlow:Point("BOTTOMRIGHT", frame, offset, -(E.PixelMode and offset or offset-1))
	end

	if powerGlow then
		powerGlow:ClearAllPoints()
		powerGlow:Point("TOPLEFT", power, -offset, offset)
		powerGlow:Point("TOPRIGHT", power, offset, offset)
		powerGlow:Point("BOTTOMLEFT", power, -offset, -offset)
		powerGlow:Point("BOTTOMRIGHT", power, offset, -offset)
	end

	if additionalPower then
		UF:FrameGlow_ClassGlowPosition(frame, "AdditionalPower", mainGlow, offset)
	elseif runes then
		UF:FrameGlow_ClassGlowPosition(frame, "Runes", mainGlow, offset)
	elseif comboPoints then
		UF:FrameGlow_ClassGlowPosition(frame, "ComboPoints", mainGlow, offset)
	elseif happiness then
		UF:FrameGlow_ClassGlowPosition(frame, "HappinessIndicator", mainGlow, offset)
	end
end

function UF:FrameGlow_CreateGlow(frame, mouse)
	-- Main Glow to wrap the health frame to it's best ability
	frame:CreateShadow()
	local mainGlow = frame.shadow
	mainGlow:SetFrameStrata("BACKGROUND")
	mainGlow:Hide()
	frame.shadow = nil

	-- Secondary Glow for power frame when using power offset or mini power
	frame:CreateShadow()
	local powerGlow = frame.shadow
	powerGlow:SetFrameStrata("BACKGROUND")
	powerGlow:Hide()
	frame.shadow = nil

	if mouse then
		mainGlow:SetFrameLevel(4)
		powerGlow:SetFrameLevel(4)
	else
		mainGlow:SetFrameLevel(3)
		powerGlow:SetFrameLevel(3)
	end

	-- Eventing Frame
	if not frame.FrameGlow then
		frame.FrameGlow = CreateFrame("Frame", nil, frame)
		frame.FrameGlow:Hide()
		frame.FrameGlow:HookScript("OnEvent", function(_, event)
			if event == "UPDATE_MOUSEOVER_UNIT" then
				UF:FrameGlow_CheckMouseover(frame)
			elseif event == "PLAYER_TARGET_CHANGED" then
				UF:FrameGlow_CheckTarget(frame)
			end
		end)
	end

	mainGlow.powerGlow = powerGlow
	return mainGlow
end

function UF:FrameGlow_SetGlowColor(glow, unit, which)
	if not glow then return end
	local option = E.db.unitframe.colors.frameGlow[which]
	local r, g, b, a = 1, 1, 1, 1

	if option.color then
		local color = option.color
		r, g, b, a = color.r, color.g, color.b, color.a
	end

	if option.class then
		local isPlayer = unit and UnitIsPlayer(unit)
		local reaction = unit and UnitReaction(unit, "player")

		if isPlayer then
			local _, class = UnitClass(unit)
			if class then
				local color = CUSTOM_CLASS_COLORS and CUSTOM_CLASS_COLORS[class] or RAID_CLASS_COLORS[class]
				if color then
					r, g, b = color.r, color.g, color.b
				end
			end
		elseif reaction then
			local color = FACTION_BAR_COLORS[reaction]
			if color then
				r, g, b = color.r, color.g, color.b
			end
		end
	end

	if which == "mouseoverGlow" then
		glow:SetVertexColor(r, g, b, a)
	else
		glow:SetBackdropBorderColor(r, g, b, a)
		if glow.powerGlow then
			glow.powerGlow:SetBackdropBorderColor(r, g, b, a)
		end
	end
end

function UF:FrameGlow_HideGlow(glow)
	if not glow then return end
	if glow:IsShown() then glow:Hide() end
	if glow.powerGlow and glow.powerGlow:IsShown() then
		glow.powerGlow:Hide()
	end
end

function UF:FrameGlow_ConfigureGlow(frame, unit, dbTexture)
	if not frame then return end

	if not unit then
		unit = frame.unit or (frame.isForced and "player")
	end

	local shouldHide
	if frame.FrameGlow and frame.FrameGlow.texture then
		if E.db.unitframe.colors.frameGlow.mouseoverGlow.enable and not (frame.db and frame.db.disableMouseoverGlow) then
			frame.FrameGlow.texture:SetTexture(dbTexture)
			UF:FrameGlow_SetGlowColor(frame.FrameGlow.texture, unit, "mouseoverGlow")
		else
			shouldHide = "texture"
		end
	end

	if frame.MouseGlow then
		if E.db.unitframe.colors.frameGlow.mainGlow.enable and not (frame.db and frame.db.disableMouseoverGlow) then
			UF:FrameGlow_SetGlowColor(frame.MouseGlow, unit, "mainGlow")
		else
			UF:FrameGlow_HideGlow(frame.MouseGlow)
			if shouldHide then
				shouldHide = "both"
			end
		end
	end

	if shouldHide then
		if shouldHide == "both" and frame.FrameGlow:IsShown() then
			frame.FrameGlow:Hide()
		elseif shouldHide == "texture" then
			frame.FrameGlow.texture:Hide()
		end
	end

	if frame.TargetGlow then
		UF:FrameGlow_CheckTarget(frame, true)
	end
end

function UF:FrameGlow_CheckTarget(frame, setColor)
	if not (frame and frame.TargetGlow and frame:IsVisible()) then return end

	local unit = frame.unit or (frame.isForced and "player")
	if E.db.unitframe.colors.frameGlow.targetGlow.enable and (unit and UnitIsUnit(unit, "target")) and not (frame.db and frame.db.disableTargetGlow) then
		if setColor then
			UF:FrameGlow_SetGlowColor(frame.TargetGlow, unit, "targetGlow")
		end
		if frame.TargetGlow.powerGlow then
			if frame.USE_POWERBAR_OFFSET or frame.USE_MINI_POWERBAR then
				frame.TargetGlow.powerGlow:Show()
			elseif frame.TargetGlow.powerGlow:IsShown() then
				frame.TargetGlow.powerGlow:Hide()
			end
		end
		frame.TargetGlow:Show()
	else
		UF:FrameGlow_HideGlow(frame.TargetGlow)
	end
end

function UF:FrameGlow_CheckMouseover(frame)
	if not (frame and frame.MouseGlow and frame:IsVisible()) then return end

	local shouldShow
	if UF:FrameGlow_MouseOnUnit(frame) then
		if E.db.unitframe.colors.frameGlow.mainGlow.enable and not (frame.db and frame.db.disableMouseoverGlow) then
			shouldShow = "frame"
		end
		if E.db.unitframe.colors.frameGlow.mouseoverGlow.enable and not (frame.db and frame.db.disableMouseoverGlow) then
			shouldShow = (shouldShow and "both") or "texture"
		end
	end

	if shouldShow then
		if frame.FrameGlow and not frame.FrameGlow:IsShown() then
			frame.FrameGlow:Show()
		end
		if (shouldShow == "both" or shouldShow == "frame") then
			if frame.MouseGlow.powerGlow then
				if frame.USE_POWERBAR_OFFSET or frame.USE_MINI_POWERBAR then
					frame.MouseGlow.powerGlow:Show()
				elseif frame.MouseGlow.powerGlow:IsShown() then
					frame.MouseGlow.powerGlow:Hide()
				end
			end
			frame.MouseGlow:Show()

			if (shouldShow == "frame") and frame.FrameGlow.texture and frame.FrameGlow.texture:IsShown() then
				frame.FrameGlow.texture:Hide()
			end
		end
		if (shouldShow == "both" or shouldShow == "texture") and frame.FrameGlow.texture and not frame.FrameGlow.texture:IsShown() then
			frame.FrameGlow.texture:Show()
		end
	elseif frame.FrameGlow and frame.FrameGlow:IsShown() then
		frame.FrameGlow:Hide()
	end
end

function UF:FrameGlow_Position(frame)
	if frame.FrameGlow and frame.FrameGlow.texture then
		frame.FrameGlow.texture:ClearAllPoints()
		frame.FrameGlow.texture:Point("TOPLEFT", frame.Health, "TOPLEFT")
		frame.FrameGlow.texture:Point("BOTTOMRIGHT", frame.Health:GetStatusBarTexture(), "BOTTOMRIGHT")
	end
end

function UF:Configure_FrameGlow(frame)
	if frame.FrameGlow and frame.FrameGlow.texture then
		local dbTexture = UF.LSM:Fetch("statusbar", E.db.unitframe.colors.frameGlow.mouseoverGlow.texture)
		frame.FrameGlow.texture:SetTexture(dbTexture)
	end
end

function UF:Construct_FrameGlow(frame, glow)
	if frame.Health and frame.FrameGlow then
		frame.FrameGlow:HookScript("OnHide", function(watcher)
			UF:FrameGlow_HideGlow(glow)

			if watcher.texture and watcher.texture:IsShown() then
				watcher.texture:Hide()
			end
		end)

		frame.FrameGlow:SetScript("OnUpdate", function(watcher, elapsed)
			if watcher.elapsed and watcher.elapsed > 0.1 then
				if not UF:FrameGlow_MouseOnUnit(frame) then
					watcher:Hide()
				end
				watcher.elapsed = 0
			else
				watcher.elapsed = (watcher.elapsed or 0) + elapsed
			end
		end)

		frame.FrameGlow.texture = frame.Health:CreateTexture("$parentHighlight", "OVERLAY")
		frame.FrameGlow.texture:Hide()

		UF:FrameGlow_ElementHook(frame, frame.FrameGlow.texture, "mouseoverGlow")
	end
end

function UF:Construct_MouseGlow(frame)
	local mainGlow = UF:FrameGlow_CreateGlow(frame, true)
	UF:FrameGlow_ElementHook(frame, mainGlow, "mainGlow")
	UF:Construct_FrameGlow(frame, mainGlow)
	frame.FrameGlow:RegisterEvent("UPDATE_MOUSEOVER_UNIT")

	return mainGlow
end

function UF:Construct_TargetGlow(frame)
	local targetGlow = UF:FrameGlow_CreateGlow(frame)
	UF:FrameGlow_ElementHook(frame, targetGlow, "targetGlow")
	frame.FrameGlow:RegisterEvent("PLAYER_TARGET_CHANGED")

	return targetGlow
end

function UF:FrameGlow_CheckChildren(frame, dbTexture)
	if frame.GetName then
		local pet = _G[frame:GetName().."Pet"]
		if pet then
			UF:FrameGlow_ConfigureGlow(pet, pet.unit, dbTexture)
		end

		local target = _G[frame:GetName().."Target"]
		if target then
			UF:FrameGlow_ConfigureGlow(target, target.unit, dbTexture)
		end
	end
end

function UF:FrameGlow_UpdateFrames()
	local dbTexture = UF.LSM:Fetch("statusbar", E.db.unitframe.colors.frameGlow.mouseoverGlow.texture)

	-- focus, focustarget, pet, pettarget, player, target, targettarget, targettargettarget
	for unit in pairs(self.units) do
		UF:FrameGlow_ConfigureGlow(self[unit], unit, dbTexture)
	end

	-- arena{1-5}, boss{1-5}
	for unit in pairs(self.groupunits) do
		UF:FrameGlow_ConfigureGlow(self[unit], unit, dbTexture)
	end

	-- assist, tank, party, raid, raid40, raidpet
	for groupName in pairs(self.headers) do
		assert(self[groupName], "UF FrameGlow: Invalid group specified.")
		local group = self[groupName]

		if group.GetNumChildren then
			for i = 1, group:GetNumChildren() do
				local frame = select(i, group:GetChildren())
				if frame and frame.Health then
					UF:FrameGlow_ConfigureGlow(frame, frame.unit, dbTexture)
					UF:FrameGlow_CheckChildren(frame, dbTexture)
				elseif frame then
					for n = 1, frame:GetNumChildren() do
						local child = select(n, frame:GetChildren())
						if child and child.Health then
							UF:FrameGlow_ConfigureGlow(child, child.unit, dbTexture)
							UF:FrameGlow_CheckChildren(child, dbTexture)
						end
					end
				end
			end
		end
	end
end