/// <summary>
/// Finds the one page of singers for one singer.
/// </summary>
/// <returns>The one page of singers for one singer.</returns>
/// <param name="mState">Singer state.</param>
/// <param name="singer">Singer.</param>
/// <param name="id">Identifier.</param>
public List <Singer> FindOnePageOfSingersForOneSinger(StateOfRequest mState, Singer singer, int id)
{
if ((mState == null) || (singer == null))
{
return(new List <Singer>());
}
int pageSize = mState.PageSize;
if (pageSize <= 0)
{
Console.WriteLine("The value of pageSize cannot be less than 0.");
return(new List <Singer>());
}
IQueryable <Singer> totalSingers = GetAllSingersIQueryable(mState);
if (totalSingers == null)
{
return(new List <Singer>());
}
List <Singer> singers = null;
Singer singerWithIndex = null;
IQueryable <Singer> singersTempList = null;
string orderByParam = mState.OrderBy.Trim();
if (id >= 0)
{
// There was a singer selected
singersTempList = totalSingers.Where(x => x.Id == id);
}
else
{
// No singer selected
if (orderByParam == "")
{
int sing_id = singer.Id;
singersTempList = totalSingers.Where(x => (x.Id == sing_id));
}
else if (orderByParam.Equals("SingNo", StringComparison.OrdinalIgnoreCase))
{
string sing_no = singer.SingNo.Trim();
int len = sing_no.Length;
singersTempList = totalSingers.Where(x => x.SingNo.Trim().Substring(0, len) == sing_no);
}
else if (orderByParam.Equals("SingNa", StringComparison.OrdinalIgnoreCase))
{
string sing_na = singer.SingNa.Trim();
int len = sing_na.Length;
singersTempList = totalSingers.Where(x => x.SingNa.Trim().Substring(0, len) == sing_na);
}
else
{
// not inside range of roder by then return empty lsit
return(new List <Singer>());
}
}
int totalRecords = totalSingers.Count(); // the whole singer table
bool isFound = true;
singerWithIndex = singersTempList.FirstOrDefault(); // the first one found
if (singerWithIndex == null)
{
if (totalRecords == 0)
{
// Singer Table is empty
UpdateStateOfRequest(mState, singerWithIndex, mState.CurrentPageNo, pageSize, 0, 0, true);
// return empty list
return(new List <Singer>());
}
else
{
// go to last page
singerWithIndex = totalSingers.LastOrDefault();
}
}
singer.CopyFrom(singerWithIndex); // return to calling function
// find the row number of singerWithIndex
int tempCount = 0;
foreach (var singerVar in totalSingers)
{
++tempCount; // first row number is 1
if (singerVar.Id == singerWithIndex.Id)
{
break;
}
}
int pageNo = tempCount / pageSize;
if ((pageNo * pageSize) != tempCount)
{
pageNo++;
}
int recordNo = (pageNo - 1) * pageSize;
singers = totalSingers.Skip(recordNo).Take(pageSize).ToList();
int totalPages = totalRecords / pageSize;
if ((totalPages * pageSize) != totalRecords)
{
totalPages++;
}
if (isFound)
{
// found
mState.OrgId = singer.Id; // chnaged OrgId to the singer id found
}
else
{
// not found, then it is last page and last record
mState.OrgId = 0; // no singer is selected
}
UpdateStateOfRequest(mState, singers.FirstOrDefault(), pageNo, pageSize, totalRecords, totalPages, true);
return(singers);
}
