ImageLoad = {}

local imgAssetMap = {}
local imgQueue = Queue.new(2000)

local function DownLoadImg(url)
	local www = UnityEngine.WWW(url)
	coroutine.www(www)
	if string.utf8len(www.error) == 0 then
        local obj = imgAssetMap[url]
        if obj and not obj.load then
            local texture = www.texture
            www:Dispose()
            if (texture ~= null) then
                local ntexture = FairyGUI.NTexture(texture)
                obj.ntexture = ntexture
                obj.load = true
                obj.co = nil
            end
        end
	end
end

local function SetTexture()
    if (imgQueue:Count() > 0) then
        local tem = imgQueue:Dequeue()
        local obj = imgAssetMap[tem.url]
        if not tem._iconObject.isDisposed and obj then
            if obj.load then
                tem._iconObject.texture = obj.ntexture
                if tem.callback then
                    tem.callback()
                end
            else
                imgQueue:Enqueue(tem)
            end
        end
    end
end
UpdateBeat:Add(SetTexture)

-- group 图片分组
function ImageLoad.Load(url,_iconObject,group,callback)
 	if string.utf8len(url) == 0 then
 		return
 	end
    if not group then
        group = "common"
    end
    

 	local asset = imgAssetMap[url]
   
    if (asset ~= nil) then
        if asset.load then
            _iconObject.texture = asset.ntexture
            if callback then callback() end
        else
            imgQueue:Enqueue({url = url,_iconObject = _iconObject,callback = callback})
        end
        return
    end
    
    local _co = coroutine.start(DownLoadImg,url)
    -- local _co_load = coroutine.start(SetTexture,_iconObject,url,callback)
    imgAssetMap[url] = {group = group,load=false,co = _co}
    imgQueue:Enqueue({url = url,_iconObject = _iconObject,callback = callback})
end 

function ImageLoad.Clear(group)
    for i,v in pairs(imgAssetMap) do
        if v.group == group then
            if v.co then
                coroutine.stop(v.co)
            end
            -- if v.co_load then
            --     coroutine.stop(v.co_load)
            -- end
            if v.load then
                imgAssetMap[i].ntexture:Unload(true)
            end
            imgAssetMap[i] = nil
        end
    end
end