ImageLoad = {}

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

local function DownLoadImg(url)
    local www = UnityEngine.WWW(url)
    coroutine.www(www)
    if (www.error == nil or www.error == "") and www.bytesDownloaded > 0 then
        local texture = www.texture
        if texture ~= nil and texture.width > 2 and texture.height > 2 then
            local obj = imgAssetMap[url]
            if obj and not obj.load then
                www:Dispose()
                if (texture ~= null) then
                    local ntexture = FairyGUI.NTexture(texture)
                    obj.ntexture = ntexture
                    obj.load = true
                    obj.co = nil
                end
            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
                local _co = coroutine.start(DownLoadImg, tem.url)
                -- local _co_load = coroutine.start(SetTexture,_iconObject,url,callback)
                tem.co = _co
                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