private async Task <IEnumerable <byte[]> > GetUniqueNodeCountsAsync(Shape shape)
{
const int ThreadCount = 1;
var tableau = shape.CreateTableau();
var terminalNodePairs = tableau.TerminalNodeUniqueCombinations()
.GroupBy(nodePair => (TerminalNode)nodePair.Node1)
.Select(grp => (
startNode: grp.Key,
endNodes: grp.Select(node => (TerminalNode)node.Node2).ToList()))
.ToList();
var jobSpecs = terminalNodePairs.Select(nodePair =>
new PathFinderJobSpec
{
Tableau = tableau,
Name = nodePair.startNode.Index.ToString(),
StartPoint = nodePair.startNode,
EndPoints = nodePair.endNodes.ToList(),
ThreadCount = ThreadCount
}).ToList();
var combinedNodeCounts = new Dictionary <byte[], int>(new ByteSequenceEqualEqualityComparer());
var tokenSource = new CancellationTokenSource();
var tasks = new List <Task <(IDictionary <byte[], int>, PathFinderState)> >();
foreach (var jobSpec in jobSpecs)
{
var pathFinderJob = new PathFinderJob(jobSpec);
var pathFinderState = new PathFinderState
{
Name = jobSpec.Name,
Steps = jobSpec.StartPoint.Links.Select(link => new Step(link.Value, link.Key)).ToList(),
Progress = new Progress()
};
tasks.Add(pathFinderJob.ExploreAsync(pathFinderState, tokenSource.Token));
}
await Task.WhenAll(tasks);
foreach (var task in tasks)
{
var(nodeCounts, pathFinderState) = task.Result;
foreach (var nodeCount in nodeCounts)
{
if (!combinedNodeCounts.TryAdd(nodeCount.Key, nodeCount.Value))
{
combinedNodeCounts[nodeCount.Key] += nodeCount.Value;
}
}
}
return(combinedNodeCounts
.Where(kv => kv.Value == 1)
.Select(kv => kv.Key));
}
//TODO: Make this a Job
private void Awake()
{
CurrentState = PathFinderState.StateIdle;
PathNodeOpen = new List <PathNode>();
PathNodeClosed = new List <PathNode>();
PathNodeFinal = new List <PathNode>();
AdjacentNodes = new List <Tile>();
}
public static async Task Main(string[] args)
{
Trace.Listeners.Add(new TextWriterTraceListener(Console.Out));
if (!Directory.Exists(Configuration.FolderName))
{
Directory.CreateDirectory(Configuration.FolderName);
}
var shape = GetShape(args);
var tableau = shape.CreateTableau();
var concurrency = GetConcurrency(args);
var persistInterval = GetPersistInterval(args);
var terminalNodePairs = tableau.TerminalNodeUniqueCombinations()
.GroupBy(nodePair => (TerminalNode)nodePair.Node1)
.Select(grp => (
startNode: grp.Key,
endNodes: grp.Select(node => (TerminalNode)node.Node2).ToList()))
.ToList();
foreach (var(startNode, endNodes) in terminalNodePairs)
{
Trace.WriteLine($"{startNode.Index}: {string.Join(", ", endNodes.Select(node => node.Index))}");
}
var jobs = new List <(PathFinderJob, PathFinderState)>();
foreach (var(startNode, endNodes) in terminalNodePairs)
{
var jobAdded = false;
var jobSpec = new PathFinderJobSpec
{
Name = startNode.Index.ToString(),
Tableau = tableau,
StartPoint = startNode,
EndPoints = endNodes,
ThreadCount = concurrency,
MonitorInterval = persistInterval
};
if (persistInterval > TimeSpan.Zero)
{
var saveFilePath = Configuration.Filename(shape, jobSpec.Name);
Trace.WriteLine($"Save file path: {saveFilePath}");
if (File.Exists(saveFilePath))
{
var savedState = RouteStateReaderWriter.ReadFromFile(saveFilePath);
if (savedState.Shape != shape.Name)
{
throw new Exception($"The shape {savedState.Shape} specfied in file '{saveFilePath}' does not match the expected value {shape.Name}.");
}
if (savedState.Size != shape.Size)
{
throw new Exception($"The size {savedState.Size} specfied in file '{saveFilePath}' does not match the expected value {shape.Size}.");
}
var endPoints = savedState.TerminalNodes
.Select(index => tableau.TerminalNodes[index])
.ToList();
var steps = new List <Step>();
var queue = new Queue <(Step step, int id)>();
var items = savedState.Steps.Where(x => x.PreviousId == 0).ToList();
foreach (var item in items)
{
var step = new Step(
node: tableau.Nodes[item.Position],
direction: new Direction(item.Direction));
queue.Enqueue((step, item.Id));
}
while (queue.Any())
{
var(previousStep, id) = queue.Dequeue();
items = savedState.Steps.Where(x => x.PreviousId == id).ToList();
if (items.Count == 0)
{
steps.Add(previousStep);
continue;
}
foreach (var item in items)
{
var direction = new Direction(item.Direction);
var twist = direction - previousStep.Direction;
var step = new Step(
node: tableau.Nodes[item.Position],
direction: direction,
twist: twist,
previous: previousStep);
queue.Enqueue((step, item.Id));
}
}
var pathFinderJob = new PathFinderJob(jobSpec); //TODO: paths
var pathFinderState = new PathFinderState
{
Name = jobSpec.Name,
Steps = steps,
Progress = savedState.Progress
};
jobs.Add((pathFinderJob, pathFinderState));
jobAdded = true;
}
}
if (!jobAdded)
{
var pathFinderJob = new PathFinderJob(jobSpec);
var pathFinderState = new PathFinderState
{
Name = jobSpec.Name,
Steps = startNode.Links.Select(link => new Step(link.Value, link.Key)).ToList(),
Progress = new Progress()
};
jobs.Add((pathFinderJob, pathFinderState));
}
}
var tokenSource = new CancellationTokenSource();
var tasks = new List <Task <(IDictionary <byte[], int>, PathFinderState)> >();
foreach (var(pathFinderJob, pathFinderState) in jobs)
{
tasks.Add(pathFinderJob.ExploreAsync(pathFinderState, tokenSource.Token));
}
await Task.WhenAll(tasks);
var combinedElapsedTime = TimeSpan.Zero;
var combinedRouteCount = 0L;
var combinedNodeCounts = new Dictionary <byte[], int>(new ByteSequenceEqualEqualityComparer());
foreach (var task in tasks)
{
var(nodeCounts, pathFinderState) = task.Result;
foreach (var nodeCount in nodeCounts)
{
if (!combinedNodeCounts.ContainsKey(nodeCount.Key))
{
combinedNodeCounts.Add(nodeCount.Key, 0);
}
combinedNodeCounts[nodeCount.Key] += nodeCount.Value;
}
var uniqueSolutionCount = nodeCounts.Count(item => item.Value == 1);
combinedRouteCount += pathFinderState.Progress.RouteCount;
if (pathFinderState.Progress.ElapsedTime > combinedElapsedTime)
{
combinedElapsedTime = pathFinderState.Progress.ElapsedTime;
}
Trace.WriteLine($"Result for job {pathFinderState.Name}: routes = {pathFinderState.Progress.RouteCount}, distinct solutions = {nodeCounts.Count}, unique solutions = {uniqueSolutionCount}, elapsed time = {pathFinderState.Progress.ElapsedTime}");
}
var combinedUniqueSolutionCount = combinedNodeCounts.Count(item => item.Value == 1);
Trace.WriteLine($"Overall result: routes = {combinedRouteCount}, distinct solutions = {combinedNodeCounts.Count}, unique solutions = {combinedUniqueSolutionCount}, elapsed time = {combinedElapsedTime}");
}
public async Task <(IDictionary <byte[], int> nodeCounts, PathFinderState state)> ExploreAsync(
PathFinderState state,
CancellationToken cancellationToken)
{
var routeCount = state.Progress.RouteCount;
var stopwatch = Stopwatch.StartNew();
var routes = new BlockingCollection <Step>(new ConcurrentStack <Step>());
foreach (var step in state.Steps)
{
routes.Add(step);
}
var latch = new ManualResetEventSlim(initialState: true);
void StartWalkAction() => Interlocked.Add(ref routeCount, StartWalk(routes, latch));
while (routes.Any())
{
var tasks = Enumerable.Range(0, _threadCount)
.Select(index => Task.Run(StartWalkAction, cancellationToken))
.ToList();
if (_monitorInterval > TimeSpan.Zero)
{
var persistTask = Task.Delay(_monitorInterval, cancellationToken)
.ContinueWith(_ => latch.Reset(), TaskContinuationOptions.ExecuteSynchronously);
tasks.Add(persistTask);
}
await Task.WhenAll(tasks);
if (_monitorInterval > TimeSpan.Zero)
{
//TODO: export paths
var routeLog = RouteLogFactory.CreateRouteLog(
_tableau,
_endPoints,
routes.ToArray(),
new Progress
{
RouteCount = routeCount,
ElapsedTime = state.Progress.ElapsedTime + stopwatch.Elapsed
});
RouteStateReaderWriter.WriteToFile(routeLog, _saveFilePath);
}
latch.Set();
}
stopwatch.Stop();
return(
nodeCounts : _nodeCounts,
state : state with
{
Steps = routes.ToList(),
Progress = new Progress
{
RouteCount = routeCount,
ElapsedTime = state.Progress.ElapsedTime + stopwatch.Elapsed
}
});
public List <PathNode> FindPath(Tile startingTile, Tile destinationTile)//TODO: Refactor?
{
Reset();
var startingIndex = GetTileIndex(startingTile);
var destinationIndex = GetTileIndex(destinationTile);
if (startingIndex == destinationIndex)
{
return(null);
}
CurrentState = PathFinderState.StateSearchingPath;
var hScore = GetManhattanDistanceCost(startingTile, destinationTile);
var startingNode = startingTile.GetPathNode();
startingNode.SetScore(hScore);
AddPathNodeToOpenList(startingNode);
while (IsSearchingForPath())
{
if (PathNodeOpen.Count == 0)
{
CurrentState = PathFinderState.StateError;
return(null);
}
var currentNode = PathNodeOpen[0];
MoveNodeToClosedList(currentNode);
if (GetTileIndex(currentNode.GetTile()) == destinationIndex)
{
BuildFinalNodePath(currentNode);
CurrentState = PathFinderState.StateFoundPath;
return(PathNodeFinal);
}
FindAjacentTiles(currentNode.GetTile());
for (int i = 0; i < AdjacentNodes.Count; i++)
{
var tile = AdjacentNodes[i];
if (tile == null)
{
continue;
}
if (DoesTileExistInClosedList(tile))
{
continue;
}
if (!DoesTileExistInOpenList(tile))
{
hScore = GetManhattanDistanceCost(tile, destinationTile);
var node = tile.GetPathNode();
node.SetParent(currentNode);
node.SetScore(hScore);
AddPathNodeToOpenList(node);
}
else
{
var node = GetOpenPathNodeForTile(tile);
if (currentNode.GetGScore() + 1 < node.GetGScore())
{
node.SetParent(currentNode);
SortOpenList();
}
}
}
}
return(null);
}
public void Reset()
{
CurrentState = PathFinderState.StateIdle;
ClearPathNodes();
}