Add GraphProperties and property caching

src/properties/create.jl

@@ -0,0 +1,73 @@
+"""
+   GraphProperties()
+
+Create an empty [`GraphProperties`](@ref) object.
+"""
+function GraphProperties()
+    return (
+        data = 0.0,
+        computeEffort = 0.0,
+        computeIntensity = 0.0,
+        cost = 0.0,
+        noNodes = 0,
+        noEdges = 0,
+    )::GraphProperties
+end
+
+"""
+   GraphProperties(graph::DAG)
+
+Calculate the graph's properties and return the constructed [`GraphProperties`](@ref) object.
+"""
+function GraphProperties(graph::DAG)
+    # make sure the graph is fully generated
+    apply_all!(graph)
+
+    d = 0.0
+    ce = 0.0
+    ed = 0
+    for node in graph.nodes
+        d += data(node.task) * length(node.parents)
+        ce += compute_effort(node.task)
+        ed += length(node.parents)
+    end
+
+    return (
+        data = d,
+        computeEffort = ce,
+        computeIntensity = (d == 0) ? 0.0 : ce / d,
+        cost = 0.0, # TODO
+        noNodes = length(graph.nodes),
+        noEdges = ed,
+    )::GraphProperties
+end
+
+"""
+   GraphProperties(diff::Diff)
+
+Create the graph properties difference from a given [`Diff`](@ref).
+The graph's properties after applying the [`Diff`](@ref) will be `get_properties(graph) + GraphProperties(diff)`.
+For reverting a diff, it's `get_properties(graph) - GraphProperties(diff)`.
+"""
+function GraphProperties(diff::Diff)
+    d = 0.0
+    ce = 0.0
+    c = 0.0 # TODO
+
+    ce =
+        reduce(+, compute_effort(n.task) for n in diff.addedNodes; init = 0.0) -
+        reduce(+, compute_effort(n.task) for n in diff.removedNodes; init = 0.0)
+
+    d =
+        reduce(+, data(e) for e in diff.addedEdges; init = 0.0) -
+        reduce(+, data(e) for e in diff.removedEdges; init = 0.0)
+
+    return (
+        data = d,
+        computeEffort = ce,
+        computeIntensity = (d == 0) ? 0.0 : ce / d,
+        cost = c,
+        noNodes = length(diff.addedNodes) - length(diff.removedNodes),
+        noEdges = length(diff.addedEdges) - length(diff.removedEdges),
+    )::GraphProperties
+end