def make_graph(self, init_state, max_depth=None):
graph = Graph()
new_nodes = [graph.node(init_state)]
new_nodes[0].fillcolor = "gray"
new_nodes[0].label = self.make_label(new_nodes[0].key)
depth = 0
while new_nodes and (max_depth is None or depth < max_depth):
nodes = new_nodes
new_nodes = []
depth += 1
while nodes:
node = nodes.pop()
key = node.key
node.label = self.make_label(key)
for a in self.get_enabled_actions(key):
s = self.step(key, a)
if s is None:
continue
n, exists = graph.node_check(s)
node.add_arc(n, a)
if not exists:
new_nodes.append(n)
for node in new_nodes:
node.label = self.make_label(node.key)
return graph
