ArrowHint = ArrowHint or BaseClass()

function ArrowHint:__init()
	self.mPanel = nil -- scrowView 物体
	self.mScroll = nil -- scrowView 组件
	self.mContent = nil --content物体

	self.mHorizontal = false  --是否是水平

	self.transform = nil
	self.left_down_tra = nil --左或者下的特效挂载父物体
	self.right_top_tra = nil --右或者上的特效挂载父物体
end

function ArrowHint:__delete()
	if self.mScroll then
		self.mScroll.onValueChanged:RemoveAllListeners()
	end

	if self.transfrom then
		if self.left_down_tra then
			self.transfrom:ClearUIEffect(self.left_down_tra)
		end
	
		if self.right_top_tra then
			self.transfrom:ClearUIEffect(self.right_top_tra)
		end
	end
end

-- is_hor 外部定义是否水平，覆盖掉内部判断，传空内部可自己判断
function ArrowHint:Init(transfrom, mPanel, mContent, left_down_tra, right_top_tra, layer_name, pos, scale, is_hor)
	self.transfrom = transfrom
	self.mPanel = mPanel
	self.mContent = mContent
	self.mScroll = self.mPanel:GetComponent("ScrollRect")
	self.left_down_tra = left_down_tra
	self.right_top_tra = right_top_tra

	if not self.transfrom or not self.mPanel or not self.mContent or not self.mScroll then return end

	self:SetArrowEffect(layer_name, pos, scale, is_hor)

	--self.mScroll.onValueChanged:RemoveAllListeners()
	self.mScroll.onValueChanged:AddListener(function()
		self:ShowArrow()
	end)
end

function ArrowHint:SetArrowEffect(layer_name, pos, scale, is_hor)
	if is_hor == nil then
		if self.mScroll.horizontal then
			self.mHorizontal = true
		elseif self.mScroll.vertical then
			self.mHorizontal = false
		end
	else
		self.mHorizontal = is_hor
	end

	layer_name = layer_name or "UI"
	local l_effect, r_effect
	if self.mHorizontal then
		l_effect = "effect_tubiao_007"
		r_effect = "effect_tubiao_009"
	else
		l_effect = "effect_tubiao_006"
		r_effect = "effect_tubiao_008"
	end
	if self.left_down_tra then
		self.transfrom:AddUIEffect(l_effect, self.left_down_tra, layer_name, pos, scale, true)
	end
	if self.right_top_tra then
		self.transfrom:AddUIEffect(r_effect, self.right_top_tra, layer_name, pos, scale, true)
	end

	self:ShowArrow()
end

function ArrowHint:ShowArrow()
	local offset, value
	if self.mHorizontal then
		value = self.mScroll.horizontalNormalizedPosition
		if self.mContent.sizeDelta.x > self.mPanel.sizeDelta.x then
			offset = self.mPanel.sizeDelta.x / (self.mContent.sizeDelta.x * 8)
		end
	else
		value = self.mScroll.verticalNormalizedPosition
		if self.mContent.sizeDelta.y > self.mPanel.sizeDelta.y then
			offset = self.mPanel.sizeDelta.y / (self.mContent.sizeDelta.y * 8)
		end
	end

	if offset and value then
		if self.left_down_tra then
			if value < offset then
				if self.left_down_tra.gameObject.activeInHierarchy then
					self.left_down_tra.gameObject:SetActive(false)
				end
			else
				if not self.left_down_tra.gameObject.activeInHierarchy then
					self.left_down_tra.gameObject:SetActive(true)
				end
			end
		end
		if self.right_top_tra then
			if value > 1 - offset then
				if self.right_top_tra.gameObject.activeInHierarchy then
					self.right_top_tra.gameObject:SetActive(false)
				end
			else
				if not self.right_top_tra.gameObject.activeInHierarchy then
					self.right_top_tra.gameObject:SetActive(true)
				end
			end
		end
	else
		self:SetArrowShow()
	end
end

--自行设置初始箭头指向，刚开始时，NormalizedPosition没有值，如果content用的自适应也没法立刻获取实际的长宽，所以需要自行设置一次
function ArrowHint:SetArrowShow(left_down, right_top)
	if self.left_down_tra then
		self.left_down_tra.gameObject:SetActive(left_down and true or false)
	end
	if self.right_top_tra then
		self.right_top_tra.gameObject:SetActive(right_top and true or false)
	end
end