public ObservableCollection<PlayerMatch> ApplyAlgorithm(ObservableCollection<PlayerMatch> playerMatches)
{
ObservableCollection<PlayerMatch> outputList = new ObservableCollection<PlayerMatch>();
//Join the win stats onto list of user selected players
IEnumerable<PlayerData> result = from pm in playerMatches
join ps in GetPlayerStatsForAllPlayers().DefaultIfEmpty() on pm.PlayerID equals ps.PlayerID into temp
from subtemp in temp.DefaultIfEmpty()
select new PlayerData
{
PlayerMatch = pm,
MatchWins = (subtemp == null ? 0 : subtemp.MatchWins),
MatchesPlayed = subtemp.MatchesPlayed,
WinRatio = SelectorServiceHelper.GetWinRatio(subtemp)
} into results
select results;
IList<PlayerData> playerData = result.ToList();
// Randomly shuffle list
playerData.Shuffle();
// Divide list of player data into a list per team
IEnumerable<PlayerData> firstTeam = playerData.TakeFirstHalf();
IEnumerable<PlayerData> lastTeam = playerData.TakeLastHalf();
// Get total win ratios per team
decimal? firstTeamsTotalWinRatio = firstTeam.Sum(x => x.WinRatio);
decimal? lastTeamsTotalWinRatio = lastTeam.Sum(x => x.WinRatio);
// Get difference in win ratio between teams
decimal winRatioOffset = SelectorServiceHelper.GetOffset(firstTeamsTotalWinRatio, lastTeamsTotalWinRatio);
// Prepare swap candidates based on win ratio differential
PlayerData firstSwapCandidate = firstTeam.GetClosestToWinRatio(winRatioOffset / 2);
PlayerData lastSwapCandidate = lastTeam.GetClosestToWinRatio(winRatioOffset / 2);
// Get difference in win ratio between swap candidates
decimal? candidateOffset = SelectorServiceHelper.GetOffset(firstSwapCandidate.WinRatio, lastSwapCandidate.WinRatio);
// Undertake the swap if there would be a reduction in the differential i.e. improvement in team matching
if (candidateOffset < winRatioOffset)
playerData.Swap(firstSwapCandidate, lastSwapCandidate);
// List is correctly ordered by player
outputList.DistributePlayersBasedOnListOrder(playerData);
// Assign the teams, smallest player should wear a bib
SelectorServiceHelper.AssignShortestTeamToBibs(outputList, _footballRepository);
return outputList;
}