public async Task FactsAdded(ImmutableList <Fact> added, FactGraph graph, CancellationToken cancellationToken)
{
if (initialize == null)
{
return;
}
await initialize;
var productsAdded = ImmutableList <(Product product, Inverse inverse)> .Empty;
var productsRemoved = ImmutableList <Product> .Empty;
var startReferences = added.Select(a => a.Reference).ToImmutableList();
foreach (var inverse in inverses)
{
var inversePipeline = inverse.InversePipeline;
var matchingReferences = startReferences
.Where(r => inversePipeline.Starts.Any(start => r.Type == start.Type))
.ToImmutableList();
if (matchingReferences.Any())
{
var products = inversePipeline.CanRunOnGraph
? inversePipeline.Execute(startReferences, graph)
: await factManager.Query(
startReferences,
new Specification(inversePipeline, specification.Projection),
cancellationToken);
foreach (var product in products)
{
var initialProduct = inverse.InitialSubset.Of(product);
var identifyingProduct = inverse.FinalSubset.Of(product);
if (initialProduct.Equals(this.initialAnchor))
{
if (inverse.Operation == Operation.Add)
{
productsAdded = productsAdded.Add((identifyingProduct, inverse));
}
else if (inverse.Operation == Operation.Remove)
{
productsRemoved = productsRemoved.Add(identifyingProduct);
}
}
}
}
}
if (productsAdded.Any())
{
var products = productsAdded.Select(p => p.product).ToImmutableList();
var addedGraph = await factManager.LoadProducts(products, cancellationToken);
var productAnchorProjections = DeserializeAllProducts(graph, productsAdded);
var removals = await observation.NotifyAdded(productAnchorProjections);
lock (this)
{
removalsByProduct = removalsByProduct.AddRange(removals);
}
}
if (productsRemoved.Any())
{
var removals = productsRemoved
.Select(product => removalsByProduct.GetValueOrDefault(product) !)
.Where(identity => identity != null)
.ToImmutableList();
foreach (var removal in removals)
{
await removal();
}
lock (this)
{
removalsByProduct = removalsByProduct.RemoveRange(productsRemoved);
}
}
}
