if(select(2, UnitClass("player")) ~= "DRUID") then return; end

local ns = oUF
local oUF = ns.oUF

local LDM = LibStub("LibDruidMana-1.0")

local function UpdateColor(element, cur, max)
	local parent = element.__owner

	local r, g, b, t
	if(element.colorClass) then
		t = parent.colors.class['DRUID']
	elseif(element.colorSmooth) then
		r, g, b = parent.ColorGradient(cur, max, unpack(element.smoothGradient or parent.colors.smooth))
	elseif(element.colorPower) then
		t = parent.colors.power[0]
	end

	if(t) then
		r, g, b = t[1], t[2], t[3]
	end

	if(b) then
		element:SetStatusBarColor(r, g, b)

		local bg = element.bg
		if(bg) then
			local mu = bg.multiplier or 1
			bg:SetVertexColor(r * mu, g * mu, b * mu)
		end
	end
end

local function Update(self, event, unit, currMana, maxMana)
	if(unit ~= 'player') then return end

	local element = self.DruidAltMana
	if(element.PreUpdate) then element:PreUpdate(unit) end

	local cur, max = currMana, maxMana
	if not (cur and max) then
		cur, max = LDM:GetCurrentMana(), LDM:GetMaximumMana()
	end

	element:SetMinMaxValues(0, max)
	element:SetValue(cur)

	element:UpdateColor(cur, max)

	if(element.PostUpdate) then
		return element:PostUpdate(unit, cur, max, event)
	end
end

local function Path(self, event, a, b, c, d, e)
	return (self.DruidAltMana.Override or Update) (self, event, a, b, c, d, e)
end

local function ElementEnable(self)
	self:RegisterEvent("UNIT_MANA", Path)
	self:RegisterEvent("UNIT_MAXMANA", Path)

	self.DruidAltMana:Show()

	if self.DruidAltMana.PostUpdateVisibility then
		self.DruidAltMana:PostUpdateVisibility(true, not self.DruidAltMana.isEnabled)
	end

	self.DruidAltMana.isEnabled = true

	Path(self, 'ElementEnable', 'player', UnitPowerType("player", 0))
end

local function ElementDisable(self)
	self:UnregisterEvent("UNIT_MANA", Path)
	self:UnregisterEvent("UNIT_MAXMANA", Path)

	self.DruidAltMana:Hide()

	if self.DruidAltMana.PostUpdateVisibility then
		self.DruidAltMana:PostUpdateVisibility(false, self.DruidAltMana.isEnabled)
	end

	self.DruidAltMana.isEnabled = nil

	Path(self, 'ElementDisable', 'player', UnitPowerType("player", 0))
end

local function Visibility(self, event, unit)
	local shouldEnable

	if UnitPowerType("player") ~= 0 then
		shouldEnable = true
	end

	if(shouldEnable) then
		ElementEnable(self)
	else
		ElementDisable(self)
	end
end

local function VisibilityPath(self, event, a, b, c, d, e)
	return (self.DruidAltMana.OverrideVisibility or Visibility) (self, event, a, b, c, d, e)
end

local function ForceUpdate(element)
	return VisibilityPath(element.__owner, 'ForceUpdate', element.__owner.unit)
end

local function Enable(self, unit)
	local element = self.DruidAltMana
	if(element and unit == 'player') then
		element.__owner = self
		element.ForceUpdate = ForceUpdate

		LDM:AddListener(function(currMana, maxMana)
			Update(self, "Listener", "player", currMana, maxMana)
		end, "oUF_DruidMana")

		self:RegisterEvent('PLAYER_LOGIN', VisibilityPath) -- need?
		self:RegisterEvent('PLAYER_ENTERING_WORLD', VisibilityPath)
		self:RegisterEvent('UPDATE_SHAPESHIFT_FORM', VisibilityPath) -- need?
		self:RegisterEvent('UNIT_DISPLAYPOWER', VisibilityPath)

		if(element:IsObjectType('StatusBar') and not element:GetStatusBarTexture()) then
			element:SetStatusBarTexture([[Interface\TargetingFrame\UI-StatusBar]])
		end

		if(not element.UpdateColor) then
			element.UpdateColor = UpdateColor
		end

		return true
	end
end

local function Disable(self)
	local element = self.DruidAltMana
	if(element) then
		ElementDisable(self)
		LDM:RemoveListener("oUF_DruidMana")

		self:UnregisterEvent('PLAYER_LOGIN', VisibilityPath) -- need?
		self:UnregisterEvent('PLAYER_ENTERING_WORLD', VisibilityPath)
		self:UnregisterEvent('UPDATE_SHAPESHIFT_FORM', VisibilityPath) -- need?
		self:UnregisterEvent('UNIT_DISPLAYPOWER', VisibilityPath)
	end
end

oUF:AddElement("DruidAltMana", VisibilityPath, Enable, Disable)