private static AddQuestionResult UpdateQuestion(string website, SyndicationItem item)
{
if (!questionsCollection.ContainsKey(item.Id))
{
Debug.WriteLine("{0} Skipped question.", item.Id);
return(AddQuestionResult.None);
}
JsonObject questionObject = questionsCollection.GetNamedObject(item.Id);
AddQuestionResult result = AddQuestionResult.None;
string oldTitle = questionObject.GetNamedStringOrEmptyString("Title");
string newTitle = item.Title != null ? item.Title.Text : String.Empty;
if (oldTitle != newTitle)
{
questionObject.SetNamedValue("Title", JsonValue.CreateStringValue(newTitle));
Debug.WriteLine("{0} Updated question. Different title.", item.Id);
result = AddQuestionResult.Updated;
}
string oldSummary = questionObject.GetNamedStringOrEmptyString(SummaryKey);
string newSummary = item.Summary != null ? item.Summary.Text : String.Empty;
if (oldSummary != newSummary)
{
questionObject.SetNamedValue(SummaryKey, JsonValue.CreateStringValue(newTitle));
Debug.WriteLine("{0} Updated question. Different summary.", item.Id);
result = AddQuestionResult.Updated;
}
Debug.WriteLineIf(
result == AddQuestionResult.None,
String.Format("{0} Skipped question. Up to date.", item.Id));
return(result);
}
// This method can be call simultaneously. Make sure only one thread is touching it.
public static AddQuestionsResult AddQuestions(string websiteUrl, SyndicationFeed feed, bool skipLatestPubDate)
{
AddQuestionsResult globalResult = new AddQuestionsResult();
DateTimeOffset latestPubDate = SettingsManager.GetLastestPubDate(websiteUrl);
DateTimeOffset newLatestPubDate = DateTimeOffset.MinValue;
Debug.WriteLine("{0} Current LastestPubDate is {1}.", websiteUrl, latestPubDate);
// Wait until the event is set by another thread.
addEvent.WaitOne();
try
{
CheckSettingsAreLoaded();
foreach (SyndicationItem item in feed.Items)
{
AddQuestionResult result = AddQuestionResult.None;
if (skipLatestPubDate || DateTimeOffset.Compare(item.PublishedDate.DateTime, latestPubDate) > 0)
{
result = AddQuestion(websiteUrl, item);
// Chances are we need to update the LatestPubDate.
if (result == AddQuestionResult.Added && item.PublishedDate > newLatestPubDate)
{
newLatestPubDate = item.PublishedDate;
Debug.WriteLine("{0} New LastestPubDate is {1}.", websiteUrl, newLatestPubDate);
}
}
else
{
result = UpdateQuestion(websiteUrl, item);
}
switch (result)
{
case AddQuestionResult.Added:
globalResult.AddedQuestions++;
break;
case AddQuestionResult.Updated:
globalResult.UpdatedQuestions++;
break;
}
}
// If the quesiton list did not change, there should not be a new LatestPubDate.
if (globalResult.AddedQuestions > 0)
{
SettingsManager.SetLastestPubDate(websiteUrl, newLatestPubDate);
}
return(globalResult);
}
finally
{
// Set the event, so other threads waiting on it can do their job.
addEvent.Set();
}
}
