public IEnumerable <AcknowledgementDTO> FindByKeywords(string search)
{
var keywords = textNormalizer.NormalizeText(search)
.Split(new char[] { ' ', ',' }, StringSplitOptions.RemoveEmptyEntries);
List <AcknowledgementDTO> acknowledgementDTOs = new List <AcknowledgementDTO>();
var comparer = new AcknowledgementsDtoComparer();
if (keywords.Count() == 1)
{
acknowledgementDTOs = FindBySingleKeyword(search);
}
else
{
acknowledgementDTOs = FindByMultipleKeywords(keywords);
}
return(acknowledgementDTOs.OrderByDescending(a => a.DateCreated).ToList());
}
private List <AcknowledgementDTO> FindByMultipleKeywords(string[] keywords)
{
var results = new List <AcknowledgementDTO>();
var comparer = new AcknowledgementsDtoComparer();
foreach (var keyword in keywords)
{
List <AcknowledgementDTO> acknowledgementsByUser = new List <AcknowledgementDTO>();
var usernames = manager.GetUsers(keyword)
.Select(u => u.Username)
.ToList();
foreach (var username in usernames)
{
acknowledgementsByUser.AddRange(repository.GetByUsername(username));
}
var acknowledgementsByContent = repository.GetByContent(keyword);
var acknowledgementsByTag = repository.GetByTag(keyword);
// Union the three into results by keyword
var acknowledgementsByKeyword = acknowledgementsByUser.Union(
acknowledgementsByContent.Union(acknowledgementsByTag, comparer),
comparer)
.ToList();
// On the first word or if no results are found so far, add the intersected result
if (results.Count == 0)
{
results.AddRange(acknowledgementsByKeyword);
}
// Intersect the previous result with the new intersected result and store it as current
else
{
results = results.Intersect(acknowledgementsByKeyword, comparer)
.ToList();
}
}
return(results);
}
private List <AcknowledgementDTO> FindBySingleKeyword(string search)
{
var results = new List <AcknowledgementDTO>();
var acknowledgementsByUser = new List <AcknowledgementDTO>();
var comparer = new AcknowledgementsDtoComparer();
var usernames = manager.GetUsers(search)
.Select(u => u.Username)
.ToList();
foreach (var username in usernames)
{
acknowledgementsByUser.AddRange(repository.GetByUsername(username));
}
var acknowledgementsByContent = repository.GetByContent(search);
var acknowledgementsByTag = repository.GetByTag(search);
// Add all the results
results.AddRange(acknowledgementsByUser);
results.AddRange(acknowledgementsByContent);
results.AddRange(acknowledgementsByTag);
return(results.Distinct(comparer).ToList());
}