private FlashCardItem DoCreateCardItem(Guid meaningId, String query, DGetText GetText, FlashCardItemType itemType, bool useExample)
{
FlashCardItem item = null;
SqlCeCommand cmd;
lock (_commands)
{
if (!_commands.TryGetValue(query, out cmd))
{
cmd = new SqlCeCommand(query, _connVocabulary);
cmd.Parameters.Add(new SqlCeParameter("MeaningId", SqlDbType.UniqueIdentifier));
AddCommand(cmd);
}
}
lock (_connVocabulary)
{
cmd.Parameters["MeaningId"].Value = meaningId;
using (SqlCeDataReader reader = cmd.ExecuteReader())
{
StringBuilder sb = new StringBuilder();
String example = String.Empty;
while (reader.Read())
{
if (sb.Length > 0)
sb.Append(", ");
sb.Append(GetText(reader));
if (useExample)
example = GetExampleText(reader);
}
if (sb.Length > 0)
item = new FlashCardItem(meaningId, itemType, sb.ToString(), example);
}
}
return item;
}
private bool DoAddAnswers(FlashCard card, Guid meaningId, Guid typeId, String query, DGetText GetText, FlashCardItemType itemType)
{
Debug.Assert(card != null);
SqlCeCommand cmd = null;
lock (_commands)
{
if (!_commands.TryGetValue(query, out cmd))
{
cmd = new SqlCeCommand(query, _connVocabulary);
cmd.Parameters.Add(new SqlCeParameter("TypeId", SqlDbType.UniqueIdentifier));
cmd.Parameters.Add(new SqlCeParameter("SeedId", SqlDbType.UniqueIdentifier));
AddCommand(cmd);
_commands[query] = cmd;
}
}
lock (_connVocabulary)
{
cmd.Parameters["TypeId"].Value = typeId;
for (int i = 0; i < 10 && card.InnerAnswers.Count < ANSWERS_NUMBER; ++i)
{
cmd.Parameters["SeedId"].Value = Guid.NewGuid();
using (SqlCeDataReader reader = cmd.ExecuteReader())
{
StringBuilder sb = new StringBuilder();
Guid previousMeaningId = Guid.Empty;
while (card.InnerAnswers.Count < ANSWERS_NUMBER && reader.Read())
{
Guid currentMeaningId = reader.GetGuid(0);
if (currentMeaningId != meaningId && card.InnerAnswers.Count<FlashCardItem>(x => x.Id == currentMeaningId) == 0)
{
if (currentMeaningId != previousMeaningId && previousMeaningId != Guid.Empty)
{
Debug.Assert(sb.Length > 0);
FlashCardItem item = new FlashCardItem(previousMeaningId, itemType, sb.ToString());
card.InnerAnswers.Add(item);
sb.Length = 0;
}
if (sb.Length > 0)
sb.Append(", ");
sb.Append(GetText(reader));
previousMeaningId = currentMeaningId;
}
}
if (card.InnerAnswers.Count < ANSWERS_NUMBER && previousMeaningId != Guid.Empty && sb.Length > 0)
{
FlashCardItem item = new FlashCardItem(previousMeaningId, itemType, sb.ToString());
card.InnerAnswers.Add(item);
}
}
}
}
return card.InnerAnswers.Count > 2;
}
private bool DoAddQuestion(FlashCard card, Guid meaningId, String query, DGetText GetText, FlashCardItemType itemType)
{
Debug.Assert(card != null);
FlashCardItem item = DoCreateCardItem(meaningId, query, GetText, itemType, true);
if (item == null)
return false;
card.Question = item;
return true;
}
private bool DoAddAnswer(FlashCard card, Guid meaningId, String query, DGetText GetText, FlashCardItemType itemType)
{
Debug.Assert(card != null);
Debug.Assert(card.InnerAnswers.Count == 0);
FlashCardItem item = DoCreateCardItem(meaningId, query, GetText, itemType, false);
if (item == null)
return false;
card.InnerAnswers.Add(item);
return true;
}