private void OnSourcePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
string albumCoverId = GetImageId(d);
if (albumCoverId == null)
{
throw new ArgumentNullException("AlbumId", "The attached property 'AlbumIdProperty' must be set for an image to be cached.");
}
string uriString = (string)e.NewValue;
WebClient wc = new WebClient();
string fileName;
var matchingMapping = this.CachedImagesMappings.FirstOrDefault(o => o.ImageId == albumCoverId);
if (matchingMapping != null)
{
fileName = matchingMapping.FilePath;
}
else
{
fileName = Path.GetFileName(uriString);
}
this.TotalImageRequests++;
if (matchingMapping != null)
{
matchingMapping.TimesUsed++;
matchingMapping.LastTimeUsed = DateTime.Now;
lock (internalIsolatedStorageAccessLock)
{
using (var userStore = IsolatedStorageFile.GetUserStoreForApplication())
{
if (!userStore.FileExists(fileName))
{
throw new NotImplementedException("Cache has been deleted. Automatic rebuild of a deleted cache is not yet implemented.");
}
using (var fs = userStore.OpenFile(fileName, FileMode.Open))
{
var image = new BitmapImage();
byte[] buffer = new byte[fs.Length];
fs.BeginRead(
buffer,
0,
(int)fs.Length,
ar =>
{
var readBytes = fs.EndRead(ar);
MemoryStream ms = new MemoryStream(buffer);
_logService.Trace(string.Format("ImageCachingService.OnSourcePropertyChanged : Cached image read completed with {0} bytes", readBytes));
image.SetSource(ms);
((Image)ar.AsyncState).Source = image;
},
d);
}
}
}
}
else
{
wc.OpenReadCompleted += (s, ea) =>
{
var image = new BitmapImage();
if (wc.ResponseHeaders == null)
{
throw new WebException("Could not retrieve album cover. Please check your internet connection.");
}
// download image to a local memory stream
var contentLength = int.Parse(wc.ResponseHeaders["content-length"]);
byte[] buffer = new byte[contentLength];
ea.Result.BeginRead(
buffer,
0,
contentLength,
ar =>
{
var bytes = ea.Result.EndRead(ar);
MemoryStream ms = new MemoryStream(buffer);
_logService.Trace(string.Format("ImageCachingService.OnSourcePropertyChanged : Network read completed with {0} bytes", bytes));
image.SetSource(ms);
((Image)ea.UserState).Source = image;
Task<string> taskWriteToDisk = new Task<string>(
stream =>
{
try
{
IEnumerable<string> paths = null;
if (this.CachedImagesMappings.Count >= this.MaxBindingsLimit)
{
paths = from mapping in this.CachedImagesMappings
where mapping.LastTimeUsed < DateTime.Now.AddDays(-14)
orderby mapping.TimesUsed descending
select mapping.FilePath;
}
lock (internalIsolatedStorageAccessLock)
{
using (var userStore = IsolatedStorageFile.GetUserStoreForApplication())
{
if (paths != null && paths.Count() >= 1)
{
userStore.DeleteFile(paths.First());
}
using (var fs = userStore.CreateFile(fileName))
{
ms.Position = 0;
ms.CopyTo(fs);
}
}
}
}
catch (Exception ex)
{
throw;
}
return fileName;
},
ea.Result);
_tasksWritingOnDisk.Add(taskWriteToDisk);
taskWriteToDisk.Start();
taskWriteToDisk.ContinueWith(
taskUri =>
{
var pathInIsolatedStorage = taskUri.Result;
CachedImagesMapping cachedImagesMapping = new CachedImagesMapping
{
FilePath = pathInIsolatedStorage,
ImageId = albumCoverId,
LastTimeUsed = DateTime.Now,
TimesUsed = 1
};
this.CachedImagesMappings.Add(cachedImagesMapping);
// let's try not to kill our storage by writing too often on it.
Timer throttlingWriteToDisk = new Timer(t =>
{
_tasksWritingOnDisk.Remove(taskUri);
if (_tasksWritingOnDisk.Count > 0)
{
return;
}
Debug.WriteLine("Actual write request.");
this.RequestSave(EventArgs.Empty);
},
null,
2000,
uint.MaxValue);
},
TaskScheduler.FromCurrentSynchronizationContext());
},
d);
};
}
Uri imageUri = new Uri(uriString, UriKind.RelativeOrAbsolute);
wc.OpenReadAsync(imageUri, d);
}
private void OnSourcePropertyChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
{
string albumCoverId = GetImageId(d);
if (albumCoverId == null)
{
throw new ArgumentNullException("AlbumId", "The attached property 'AlbumIdProperty' must be set for an image to be cached.");
}
string uriString = (string)e.NewValue;
WebClient wc = new WebClient();
string fileName;
var matchingMapping = this.CachedImagesMappings.FirstOrDefault(o => o.ImageId == albumCoverId);
if (matchingMapping != null)
{
fileName = matchingMapping.FilePath;
}
else
{
fileName = Path.GetFileName(uriString);
}
this.TotalImageRequests++;
if (matchingMapping != null)
{
matchingMapping.TimesUsed++;
matchingMapping.LastTimeUsed = DateTime.Now;
lock (internalIsolatedStorageAccessLock)
{
using (var userStore = IsolatedStorageFile.GetUserStoreForApplication())
{
if (!userStore.FileExists(fileName))
{
throw new NotImplementedException("Cache has been deleted. Automatic rebuild of a deleted cache is not yet implemented.");
}
using (var fs = userStore.OpenFile(fileName, FileMode.Open))
{
var image = new BitmapImage();
byte[] buffer = new byte[fs.Length];
fs.BeginRead(
buffer,
0,
(int)fs.Length,
ar =>
{
var readBytes = fs.EndRead(ar);
MemoryStream ms = new MemoryStream(buffer);
_logService.Trace(string.Format("ImageCachingService.OnSourcePropertyChanged : Cached image read completed with {0} bytes", readBytes));
image.SetSource(ms);
((Image)ar.AsyncState).Source = image;
},
d);
}
}
}
}
else
{
wc.OpenReadCompleted += (s, ea) =>
{
var image = new BitmapImage();
if (wc.ResponseHeaders == null)
{
throw new WebException("Could not retrieve album cover. Please check your internet connection.");
}
// download image to a local memory stream
var contentLength = int.Parse(wc.ResponseHeaders["content-length"]);
byte[] buffer = new byte[contentLength];
ea.Result.BeginRead(
buffer,
0,
contentLength,
ar =>
{
var bytes = ea.Result.EndRead(ar);
MemoryStream ms = new MemoryStream(buffer);
_logService.Trace(string.Format("ImageCachingService.OnSourcePropertyChanged : Network read completed with {0} bytes", bytes));
image.SetSource(ms);
((Image)ea.UserState).Source = image;
Task <string> taskWriteToDisk = new Task <string>(
stream =>
{
try
{
IEnumerable <string> paths = null;
if (this.CachedImagesMappings.Count >= this.MaxBindingsLimit)
{
paths = from mapping in this.CachedImagesMappings
where mapping.LastTimeUsed < DateTime.Now.AddDays(-14)
orderby mapping.TimesUsed descending
select mapping.FilePath;
}
lock (internalIsolatedStorageAccessLock)
{
using (var userStore = IsolatedStorageFile.GetUserStoreForApplication())
{
if (paths != null && paths.Count() >= 1)
{
userStore.DeleteFile(paths.First());
}
using (var fs = userStore.CreateFile(fileName))
{
ms.Position = 0;
ms.CopyTo(fs);
}
}
}
}
catch (Exception ex)
{
throw;
}
return(fileName);
},
ea.Result);
_tasksWritingOnDisk.Add(taskWriteToDisk);
taskWriteToDisk.Start();
taskWriteToDisk.ContinueWith(
taskUri =>
{
var pathInIsolatedStorage = taskUri.Result;
CachedImagesMapping cachedImagesMapping = new CachedImagesMapping
{
FilePath = pathInIsolatedStorage,
ImageId = albumCoverId,
LastTimeUsed = DateTime.Now,
TimesUsed = 1
};
this.CachedImagesMappings.Add(cachedImagesMapping);
// let's try not to kill our storage by writing too often on it.
Timer throttlingWriteToDisk = new Timer(t =>
{
_tasksWritingOnDisk.Remove(taskUri);
if (_tasksWritingOnDisk.Count > 0)
{
return;
}
Debug.WriteLine("Actual write request.");
this.RequestSave(EventArgs.Empty);
},
null,
2000,
uint.MaxValue);
},
TaskScheduler.FromCurrentSynchronizationContext());
},
d);
};
}
Uri imageUri = new Uri(uriString, UriKind.RelativeOrAbsolute);
wc.OpenReadAsync(imageUri, d);
}
