/// Actions
async Task InitialScan()
{
var stopwatch = Stopwatch.StartNew();
ReportLine("Started initial scan\n");
StorageItemQueryResult query = CreateQuery();
try
{
using (await _lock.LockAsync())
{
int itemIndex = 0;
uint chunkIndex = 0;
uint chunkSize = 50;
var chunkItems = new List <MonitoredFolderItem>((int)chunkSize);
int addedCount = 0;
do
{
if (_cancellationToken.IsCancellationRequested)
{
break;
}
// Get items
var items = await query.GetItemsAsync(chunkIndex, chunkSize);
if (!items.Any())
{
break;
}
Report(".");
// Gather added items
chunkItems.Clear();
foreach (var item in items)
{
if (_cancellationToken.IsCancellationRequested)
{
break;
}
var itemName = item.Name;
var newItem = new MonitoredFolderItem(item);
_cachedItems.Insert(itemIndex, newItem);
chunkItems.Add(newItem);
itemIndex++;
}
if (_cancellationToken.IsCancellationRequested)
{
break;
}
if (chunkItems.Any())
{
addedCount += chunkItems.Count;
// Raise event
Changed?.Invoke(this, new MonitoredFolderChangedArgs(chunkItems));
}
// Move Next
chunkIndex += (uint)items.Count();
}while (true);
stopwatch.Stop();
ReportLine($"+{addedCount}");
ReportLine($"Finished initial scan. Processed {chunkIndex} items in {stopwatch.ElapsedMilliseconds} ms.");
ReportLine("Releasing Lock");
}
}
catch (Exception ex)
{
ReportLine($"Exception\n{ex}");
}
}
async Task Scan()
{
var scanId = ++_debugScanCount;
ReportLine(scanId, "Started");
try
{
using (await _lock.LockAsync())
{
_isScanQueued = false;
ReportLine(scanId, "Obtained Lock\n");
var stopwatch = Stopwatch.StartNew();
var query = CreateQuery();
uint chunkIndex = 0;
uint chunkSize = 50;
var chunkItemsAdded = new List <MonitoredFolderItem>((int)chunkSize);
var chunkItemsRemoved = new List <MonitoredFolderItem>((int)chunkSize);
int addedCount = 0;
int removedCount = 0;
int thisIndex = -1;
int existingIndex = -1;
var existingItems = _cachedItems.ToList();
do
{
if (_cancellationToken.IsCancellationRequested)
{
break;
}
var items = await query.GetItemsAsync(chunkIndex, chunkSize);
if (!items.Any())
{
break;
}
Report(".");
foreach (var item in items)
{
if (_cancellationToken.IsCancellationRequested)
{
break;
}
thisIndex++;
var thisItem = new MonitoredFolderItem(item);
existingIndex++;
if (existingIndex < existingItems.Count)
{
var existingItem = existingItems[existingIndex];
if (existingItem.Equals(thisItem))
{
continue;
}
var comparison = existingItem.CompareTo(thisItem);
// Delete all existingItems at this index < thisItem
while (comparison < 0)
{
existingItems.RemoveAt(existingIndex);
chunkItemsRemoved.Add(existingItem);
if (existingItems.Count == existingIndex)
{
break;
}
existingItem = existingItems[existingIndex];
comparison = existingItem.CompareTo(thisItem);
}
if (existingIndex == existingItems.Count)
{
existingItems.Add(thisItem);
chunkItemsAdded.Add(thisItem);
}
else if (comparison > 0)
{
existingItems.Insert(existingIndex, thisItem);
chunkItemsAdded.Add(thisItem);
}
}
else
{
existingItems.Add(thisItem);
chunkItemsAdded.Add(thisItem);
}
}
if (_cancellationToken.IsCancellationRequested)
{
break;
}
// Raise event
if (chunkItemsAdded.Any() || chunkItemsRemoved.Any())
{
await UIThread.InvokeAsync(() => { Changed?.Invoke(this, new MonitoredFolderChangedArgs(chunkItemsAdded, chunkItemsRemoved)); });
addedCount += chunkItemsAdded.Count;
removedCount += chunkItemsRemoved.Count;
chunkItemsAdded.Clear();
chunkItemsRemoved.Clear();
}
// Move Next
chunkIndex += (uint)items.Count();
}while (true);
// Any remaining existingItems are removed
if (existingIndex < existingItems.Count - 1)
{
var itemsToRemove = existingItems.Where((_, i) => i > existingIndex).ToList();
chunkItemsRemoved.Clear();
chunkItemsRemoved.AddRange(itemsToRemove);
removedCount += itemsToRemove.Count;
var numberToRemove = existingItems.Count - 1 - existingIndex;
existingItems.RemoveRange(existingItems.Count - numberToRemove, numberToRemove);
await UIThread.InvokeAsync(() => { Changed?.Invoke(this, new MonitoredFolderChangedArgs(null, chunkItemsRemoved)); });
}
// Result
_cachedItems = existingItems;
stopwatch.Stop();
if (chunkIndex > 0)
{
ReportLine($"+{addedCount} -{removedCount}");
}
ReportLine(scanId, $"Finished. Processed {chunkIndex} items in {stopwatch.ElapsedMilliseconds} ms.");
ReportLine("Releasing Lock");
}
}
catch (Exception ex)
{
ReportLine(scanId, $"Exception\n{ex}");
}
}