--拖住功能
DragViewMgr = DragViewMgr or BaseClass()

local DragViewMgr = DragViewMgr

DragViewMgr.TouchType = 
{
	TouchDown = 1,
	TouchMove = 2,
	TouchUp = 3,
}

function DragViewMgr:__init()
	self.base_file = false
	self.layout_file = false
	self.begin_callback = false
	self.draging_callback = false
	self.end_callback = false
	self.item_class = false

	self.drag_cache_item = false
	self.start_drag = false
	self.draging = false

	self.old_pos = false	
end

function DragViewMgr:Init(info)
	self.base_file = info.base_file
	self.layout_file = info.layout_file
	self.begin_callback = info.begin_callback
	self.draging_callback = info.draging_callback
	self.end_callback = info.end_callback
	self.item_class = info.item_class
	self.item_parent = info.item_parent or MainUIController:GetInstance().GoodsFlyView.transform

end

function DragViewMgr:__delete()
	if self.drag_cache_item then
		self.drag_cache_item:DeleteMe()
		self.drag_cache_item = nil
	end
end

function DragViewMgr:Start()
	self.start_drag = true
	self.draging = false
	Runner.Instance:AddRunObj(self, 1)
end

function DragViewMgr:Stop()	
	Runner.Instance:RemoveRunObj(self)
	self.start_drag = false
	self.draging = false
	self.old_pos = false
end

function DragViewMgr:OnDragBegin(pos)
	if not pos then return end

	if not self.drag_cache_item then
		self.drag_cache_item = self:CreatDragItem()
	end
	if not self.drag_cache_item then
		print(">>>>>>>>>>>> 拖拽物体没有创建成功")
		return
	end
	if self.begin_callback then
		self.begin_callback(self.drag_cache_item)
	end
	self.drag_cache_item:SetVisible(true)
    local w = ScreenWidth
    local h = ScreenHeight
    pos.x = w / 2 + pos.x
    pos.y = h / 2 + pos.y
    self.drag_cache_item:SetPosition(pos.x, pos.y)

end

function DragViewMgr:CreatDragItem()
	local item = nil
	if self.item_class ~= nil then
		item = self.item_class.New(self.item_parent)
		self.drag_cache_item = item
	end
	return item
end

function DragViewMgr:OnDragIng(pos)
	local w = ScreenWidth
	local h = ScreenHeight
	pos.x = w / 2 + pos.x
	pos.y = h / 2 + pos.y
	if self.drag_cache_item then
    	self.drag_cache_item:SetPosition(pos.x, pos.y)
	end	
	if self.draging_callback then
		self.draging_callback(self.drag_cache_item, pos)
	end
end

function DragViewMgr:OnDragEnd(pos)	
	Runner.Instance:RemoveRunObj(self)
	if self.end_callback then
		self.end_callback(self.drag_cache_item, pos)
	end	
	if self.drag_cache_item then
		self.drag_cache_item:SetVisible(false)
	end
end

function DragViewMgr:Update()
	if not self.start_drag then return end

	local touch_type, pos = self:GetDragTouchTypeAndPos()
	if not pos or not touch_type then
		if self.draging then
			self:Stop()
			self:OnDragEnd(self.old_pos)
		end
	end

	if touch_type == DragViewMgr.TouchType.TouchDown or touch_type == DragViewMgr.TouchType.TouchMove then		
		if not self.draging then	
			self:OnDragBegin(pos)
			self.draging = true
			self.old_pos = pos
			return
		end

		self.old_pos = pos
		self:OnDragIng(pos)
	else
		self:OnDragEnd(pos)
		self:Stop()
	end	
end

function DragViewMgr:GetDragTouchTypeAndPos()
	local touch_type = nil
	local pos = nil
	if Input.touchCount > 0  then
		local touch = Input.GetTouch(0)
		if touch then
			pos = touch.position
			pos.x = pos.x / ScreenConvertRatio  - ScreenWidth*0.5
			pos.y = pos.y / ScreenConvertRatio  - ScreenHeight*0.5			
			if touch.phase == TouchPhase.Began then
				touch_type = DragViewMgr.TouchType.TouchDown
			elseif touch.phase == TouchPhase.Moved then
				touch_type = DragViewMgr.TouchType.TouchMove
			elseif touch.phase == TouchPhase.Ended then
				touch_type = DragViewMgr.TouchType.TouchUp
			end
		end
	else
		if Input.GetMouseButtonDown(0) then
		--	print(">>>>>>>>>>>>  GetMouseButtonDown")
			pos = Vector2(0,0)	
			pos.x = Input.mousePosition.x / ScreenConvertRatio  - ScreenWidth*0.5
			pos.y = Input.mousePosition.y / ScreenConvertRatio  - ScreenHeight*0.5
			touch_type = DragViewMgr.TouchType.TouchDown
		elseif Input.GetMouseButtonUp(0) then
		--	print(">>>>>>>>>>>>  GetMouseButtonUp")
			pos = Vector2(0,0)	
			pos.x = Input.mousePosition.x / ScreenConvertRatio  - ScreenWidth*0.5
			pos.y = Input.mousePosition.y / ScreenConvertRatio  - ScreenHeight*0.5
			touch_type = DragViewMgr.TouchType.TouchUp
		elseif Input.GetMouseButton(0) then
			--print(">>>>>>>>>>>>  GetMouseButton")
			pos = Vector2(0,0)	
			pos.x = Input.mousePosition.x / ScreenConvertRatio  - ScreenWidth*0.5
			pos.y = Input.mousePosition.y / ScreenConvertRatio  - ScreenHeight*0.5
			touch_type = DragViewMgr.TouchType.TouchMove
		end	
	end	
	return touch_type, pos
end