public static bool Evaluate <T>(Context <T> ctx)
{
if (ctx.procTermination.Invoke(ctx.start))
{
ctx.path = new List <T>();
return(true);
}
var opened = new MinHeap <T>();
var map = new Dictionary <int, Node <T> >();
var closed = new HashSet <int>();
var startNode = new Node <T>(ctx.start, 0, 0);
foreach (var adj in ctx.procAdjacencies.Invoke(ctx.start))
{
var node = new Node <T>(adj,
ctx.procWeight.Invoke(ctx.start, adj),
ctx.procDistanceEstimator(adj));
node.backwardRef = startNode;
map.Add(ctx.procTrait.Invoke(node.substance), node);
opened.AddNode(node);
}
closed.Add(ctx.procTrait.Invoke(ctx.start));
List <Node <T> > matches = new List <Node <T> >();
while (opened.Length > 0)
{
matches.Clear();
var cur = opened.ExtractMin();
if (ctx.procTermination.Invoke(cur.substance))
{
ctx.path = new List <T>();
var step = cur;
while (null != step)
{
ctx.path.Add(step.substance);
step = step.backwardRef;
}
return(true);
}
var adjs = ctx.procAdjacencies.Invoke(cur.substance);
closed.Add(ctx.procTrait.Invoke(cur.substance));
map.Remove(ctx.procTrait.Invoke(cur.substance));
foreach (var adj in adjs)
{
if (closed.Contains(ctx.procTrait.Invoke(adj)))
{
continue;
}
var estimation = ctx.procDistanceEstimator.Invoke(adj);
var dstIncrease = ctx.procWeight.Invoke(cur.substance, adj);
if (map.ContainsKey(ctx.procTrait.Invoke(adj)))
{
var exist = map[ctx.procTrait.Invoke(adj)];
if (cur.dstStart + dstIncrease + estimation < exist.dstStart + exist.dstEndEstimated)
{
exist.dstStart = cur.dstStart + dstIncrease;
exist.backwardRef = cur;
opened.HeapifyAll();
}
}
else
{
var node = new Node <T>(adj, cur.dstStart + dstIncrease, ctx.procDistanceEstimator(adj));
node.backwardRef = cur;
map.Add(ctx.procTrait.Invoke(adj), node);
opened.AddNode(node);
}
}
}
return(false);
}
