/// <summary>
/// Download the thumbnail for the specified video (only if it isn't already in our cache)
/// </summary>
public void DownloadThumbnail(IVideo video)
{
if (!_thumbnails.Contains(video))
{
// if we can get a version of the thumbnail from the cache
// then just save this version
PluginHttpRequest pluginHttpRequest = new PluginHttpRequest(video.ThumbnailUrl, HttpRequestCacheLevel.CacheOnly);
using (Stream cachedStream = pluginHttpRequest.GetResponse())
{
if (cachedStream != null)
{
MemoryStream memoryStream = new MemoryStream();
StreamHelper.Transfer(cachedStream, memoryStream);
_thumbnails[video] = new VideoThumbnail(memoryStream);
}
// otherwise mark it as 'downloading' and enque the download
else
{
_thumbnails[video] = new DownloadingVideoThumbnail();
_workQueue.Enqueue(video);
}
}
}
}
/// <summary>
/// Download the thumbnail -- return null if any error (connection, r/w, timeout, etc.) occurs
/// </summary>
private static Stream SafeDownloadThumbnail(IVideo ivideo)
{
try
{
// download the thumbnail
PluginHttpRequest pluginHttpRequest = new PluginHttpRequest(ivideo.ThumbnailUrl, HttpRequestCacheLevel.CacheIfAvailable);
using (Stream downloadedStream = pluginHttpRequest.GetResponse(5000))
{
if (downloadedStream != null)
{
// transfer it to a memory stream so we don't hold open the network connection
// (creating a Bitmap from a Stream requires that you hold open the Stream for
// the lifetime of the Bitmap and we clearly don't want to do this for Streams
// loaded from the network!)
Stream memoryStream = new MemoryStream();
StreamHelper.Transfer(downloadedStream, memoryStream);
return memoryStream;
}
else
{
return null;
}
}
}
catch
{
return null;
}
}
private bool ValidatePushpinUrl()
{
using (new WaitCursor())
{
// empty url is ok, means no custom pushpin
if (PushpinUrl == String.Empty)
return true;
// try to validate (take no more than 5 seconds)
try
{
PluginHttpRequest request = new PluginHttpRequest(PushpinUrl, HttpRequestCacheLevel.CacheIfAvailable);
using (Stream response = request.GetResponse(5000))
{
if (response == null)
return ShowPushpinValidationError();
else
return true;
}
}
catch (Exception)
{
return ShowPushpinValidationError();
}
}
}