public VerseHistoryTask(
UserSession us,
UserProfile user_profile,
Verse start,
Verse end,
DateTime datetime,
VerseHistoryRecord vhr)
{
this.us = us;
this.user_profile = user_profile;
this.start = start;
this.end = end;
this.datetime = datetime;
this.vhr = vhr;
}
private void loadVerseHistoryFromDB(
UserProfile user_profile,
UserSession user_session)
{
string sqlQuery =
"SELECT id, user_id, session_id, datetime, start_verse, end_verse " +
" FROM versehistory WHERE user_id = '" + user_profile.id +"'" +
" AND deleted = 0 ORDER BY id desc LIMIT 0," +HISTORY_MAX_SIZE;
MySqlConnection conn = DBManager.getConnection();
MySqlDataReader rdr = null;
try
{
conn.Open();
MySqlCommand cmd = new MySqlCommand(sqlQuery, conn);
rdr = cmd.ExecuteReader();
long id = -1;
long user_id= -1;
long session_id= -1;
DateTime datetime;
String start_verse;
String end_verse;
while (rdr.Read())
{
id = long.Parse((rdr[0]).ToString());
user_id = long.Parse((rdr[1]).ToString());
session_id = long.Parse((rdr[2]).ToString());
datetime = DateTime.Parse(rdr[3].ToString());
start_verse = rdr[4].ToString();
end_verse = rdr[5].ToString();
VerseHistoryRecord vhr = new VerseHistoryRecord(
id,
user_id,
session_id,
datetime,
start_verse,
end_verse);
history_list.AddLast(vhr);
}
}
catch (Exception ex)
{
Console.WriteLine(ex.StackTrace);
}
finally
{
if (rdr != null)
rdr.Close();
conn.Close();
}
}
/*this stores the last request and is responsible for maintaining synchronisation between memory
* and DB views.
*/
public void saveVerseRequest(
UserSession user_session,
UserProfile user_profile,
Verse start_verse,
Verse end_verse)
{
DateTime dt = DateTime.Now;
//update DB
String verse_start_str = start_verse.getVerseReference();
String verse_end_str;
if (end_verse == null)
verse_end_str = "NULL";
else
verse_end_str = end_verse.getVerseReference();
//now update in Memory View.
VerseHistoryRecord vhr = new VerseHistoryRecord(
-1,
user_profile.id,
user_session.session_id,
dt,
verse_start_str,
verse_end_str);
saveVerseRequestToDB(
user_session,
user_profile,
start_verse,
end_verse,
dt,
vhr);
if (history_list.Count() < HISTORY_MAX_SIZE)
{
history_list.AddFirst(vhr);
}
else //this should correspond to the list HISTORY_MAX_SIZE size because it should never grow more than this
{
history_list.RemoveLast();
history_list.AddFirst(vhr);
}
}
/*this method updates the DB in seperate thread. to increase performance.
*/
private static void saveVerseRequestToDB(
UserSession user_session,
UserProfile user_profile,
Verse start,
Verse end,
DateTime datetime,
VerseHistoryRecord vhr)
{
VerseHistoryTask vht = new VerseHistoryTask(
user_session,
user_profile,
start,
end,
datetime,
vhr);
vht.AddVerseToVerseHistory();
}