public IEnumerable <IUser[]> SearchPathesBetweenUsers(IUser firstUser, IUser secondUser, long maximalDepth)
{
PathSearcherContext <long, long> searchContext = new PathSearcherContext <long, long>(new DfsPathSearcher <long, long>());
var normalGraph = BuildUsersSocialGraph(firstUser, TreeType.Normal);
var reversedGraph = BuildUsersSocialGraph(secondUser, TreeType.Reversed);
IEnumerable <long[]> allPathes = new List <long[]>();
long currentDepth = 3;
while (!(allPathes = searchContext.Search(LeveledGraph <long, long> .Merge(normalGraph, reversedGraph), firstUser.Id, secondUser.Id)).Any() && currentDepth++ < maximalDepth)
{
if (normalGraph.Size < reversedGraph.Size)
{
normalGraph = IncreaseDepthOfUsersSocialGraph(normalGraph, TreeType.Normal);
}
else
{
reversedGraph = IncreaseDepthOfUsersSocialGraph(reversedGraph, TreeType.Reversed);
}
}
var detalized = DetalizePathes(allPathes);
return(detalized);
}
public LeveledGraph <long, long> IncreaseDepthOfUsersSocialGraph(LeveledGraph <long, long> graph, TreeType treeType)
{
var toDownloadList = GetUsersIdsOfLevel(graph, treeType == TreeType.Normal ? graph.Depth : 100 - graph.Depth);
var friendsOfFriends = DownloadFriendsIds(toDownloadList);
foreach (var friendsList in friendsOfFriends)
{
var friendId = friendsList.Key;
var friendsOfFriendIds = friendsList.Value;
foreach (var friend in friendsOfFriendIds)
{
graph.AddVertex(friend, friend, treeType == TreeType.Normal ? graph.Depth + 1 : 100 - graph.Depth - 1);
if (treeType == TreeType.Normal)
{
graph.AddEdge(friendsList.Key, friend);
}
else
{
graph.AddEdge(friend, friendsList.Key);
}
}
}
graph.Depth++;
return(graph);
}
public LeveledGraph <long, long> BuildUsersSocialGraph(IUser user, TreeType treeType)
{
var graph = new LeveledGraph <long, long>();
var downloadQueue = new SortedSet <long>();
downloadQueue.Add(user.Id);
var friendsOfFriends = DownloadFriendsIds(downloadQueue);
foreach (var friendsList in friendsOfFriends)
{
var friendId = friendsList.Key;
var friendsOfFriend = friendsList.Value;
graph.AddVertex(user.Id, user.Id, treeType == TreeType.Normal ? 0 : 100);
foreach (var friend in friendsOfFriend)
{
graph.AddVertex(friend, friend, treeType == TreeType.Normal ? 1 : 100 - 1);
if (treeType == TreeType.Normal)
{
graph.AddEdge(friendsList.Key, friend);
}
else
{
graph.AddEdge(friend, friendsList.Key);
}
downloadQueue.Add(friend);
}
}
graph.Depth = 1;
return(graph);
}
public IEnumerable <long> GetUsersIdsOfLevel(LeveledGraph <long, long> graph, long level) => graph.GetVertexesOfLevel(level);
