--[[

	Shared:
	 - BarFade [boolean]
	 - BarFadeMinAlpha [value] default: 0.25
	 - BarFadeMaxAlpha [value] default: 1

--]]
local function UpdateElement(self, unit)
	if(unit == 'player' and self.BarFade) then
		local _, class = UnitClass('player')
		local notFull = (UnitHealth('player') ~= UnitHealthMax('player')) or
			(UnitPowerType('player') ~= 1 and UnitMana('player') ~= UnitManaMax('player')) or
			(UnitPowerType('player') == 1 and UnitMana('player') > 0)

		if(notFull) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitAffectingCombat('player')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitExists('target')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(self.Castbar) then
			self:SetAlpha(self.Castbar.casting and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		else
			self:SetAlpha(self.BarFadeMinAlpha or 0.25)
		end
	end
	if(unit == 'pet' and self.BarFade) then
		local happiness = GetPetHappiness()
		local notFull = (UnitHealth('pet') ~= UnitHealthMax('pet')) or
			(UnitMana('pet') ~= UnitManaMax('pet'))

		if(notFull) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitAffectingCombat('pet')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitExists('pettarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(self.Castbar) then
			self:SetAlpha(self.Castbar.casting and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		elseif(happiness) then
			self:SetAlpha((happiness < 3) and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		else
			self:SetAlpha(self.BarFadeMinAlpha or 0.25)
		end
	end
	if(unit == 'focus' and self.BarFade) then
		local notFull = (UnitHealth('focus') ~= UnitHealthMax('focus')) or
			(UnitPowerType('focus') ~= 1 and UnitMana('focus') ~= UnitManaMax('focus')) or
			(UnitPowerType('focus') == 1 and UnitMana('focus') > 0)

		if(notFull) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitAffectingCombat('focus')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitExists('focustarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(self.Castbar) then
			self:SetAlpha(self.Castbar.casting and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		else
			self:SetAlpha(self.BarFadeMinAlpha or 0.25)
		end
	end
	if(unit == 'focustarget' and self.BarFade) then
		local notFull = (UnitHealth('focustarget') ~= UnitHealthMax('focustarget')) or
			(UnitPowerType('focustarget') ~= 1 and UnitMana('focustarget') ~= UnitManaMax('focustarget')) or
			(UnitPowerType('focustarget') == 1 and UnitMana('focustarget') > 0)

		if(notFull) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitAffectingCombat('focustarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitExists('focustargettarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(self.Castbar) then
			self:SetAlpha(self.Castbar.casting and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		else
			self:SetAlpha(self.BarFadeMinAlpha or 0.25)
		end
	end
	if(unit == 'targettarget' and self.BarFade) then
		local notFull = (UnitHealth('targettarget') ~= UnitHealthMax('targettarget')) or
			(UnitPowerType('targettarget') ~= 1 and UnitMana('targettarget') ~= UnitManaMax('targettarget')) or
			(UnitPowerType('targettarget') == 1 and UnitMana('targettarget') > 0)

		if(notFull) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitAffectingCombat('targettarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(UnitExists('targettargettarget')) then
			self:SetAlpha(self.BarFadeMaxAlpha or 1)
		elseif(self.Castbar) then
			self:SetAlpha(self.Castbar.casting and (self.BarFadeMaxAlpha or 1) or (self.BarFadeMinAlpha or 0.25))
		else
			self:SetAlpha(self.BarFadeMinAlpha or 0.25)
		end
	end
end

oUF:RegisterInitCallback(function(self)
	local addon = CreateFrame('Frame')
	addon:SetScript('OnEvent', function() UpdateElement(self, self.unit) end)
	addon:RegisterEvent('PLAYER_LOGIN')
	addon:RegisterEvent('PLAYER_REGEN_ENABLED')
	addon:RegisterEvent('PLAYER_REGEN_DISABLED')
	addon:RegisterEvent('PLAYER_TARGET_CHANGED')
	addon:RegisterEvent('PLAYER_FOCUS_CHANGED')
	addon:RegisterEvent('UNIT_HAPPINESS')
	addon:RegisterEvent('UNIT_HEALTH')
	addon:RegisterEvent('UNIT_MANA')
	addon:RegisterEvent('UNIT_ENERGY')
	addon:RegisterEvent('UNIT_FOCUS')
	addon:RegisterEvent('UNIT_RAGE')
	addon:RegisterEvent('UNIT_RUNIC_POWER')
	addon:RegisterEvent('UNIT_TARGET')
	addon:RegisterEvent('UNIT_SPELLCAST_START')
	addon:RegisterEvent('UNIT_SPELLCAST_STOP')
	addon:RegisterEvent('UNIT_SPELLCAST_CHANNEL_START')
	addon:RegisterEvent('UNIT_SPELLCAST_CHANNEL_STOP')
end)