import json
from database import NodeDB
from graph import Node, Edge

def insert_graph_data(config, json_str):
	try:
		graph_data = json.loads(json_str)
	except ValueError:
		return 'Invalid JSON'

	nodes = dict()
	edges = []

	try:
		for n in graph_data['nodes']:
			try:
				node = Node(n['ip'], version=n['version'])
				nodes[n['ip']] = node
			except Exception:
				pass

		for e in graph_data['edges']:
			try:
				edge = Edge(nodes[e['a']], nodes[e['b']])
				edges.append(edge)
			except Exception:
				pass
	except Exception:
		return 'Invalid JSON nodes'

	print "Accepted %d nodes and %d links." % (len(nodes), len(edges))

	if len(nodes) == 0 or len(edges) == 0:
		return 'No valid nodes or edges'

	try:
		with NodeDB(config) as db:
			db.insert_graph(nodes, edges)
	except Exception:
		return 'Database failure'

	return None