from functools import reduce
from itertools import chain

import networkx as nx

from lib.nodes import build_mac_table


def import_vis_data(graph, nodes, vis_data):
    macs = build_mac_table(nodes)
    nodes_a = map(lambda d: 2*[d['primary']], filter(lambda d: 'primary' in d, vis_data))
    nodes_b = map(lambda d: [d['secondary'], d['of']], filter(lambda d: 'secondary' in d, vis_data))
    graph.add_nodes_from(map(lambda a, b: (a, dict(primary=b, node_id=macs.get(b))), *zip(*chain(nodes_a, nodes_b))))

    edges = filter(lambda d: 'neighbor' in d, vis_data)
    graph.add_edges_from(map(lambda d: (d['router'], d['neighbor'], dict(tq=float(d['label']))), edges))


def mark_vpn(graph, vpn_macs):
    components = map(frozenset, nx.weakly_connected_components(graph))
    components = filter(vpn_macs.intersection, components)
    nodes = reduce(lambda a, b: a | b, components, set())

    for node in nodes:
        for k, v in graph[node].items():
            v['vpn'] = True


def to_multigraph(graph):
    def f(a):
        node = graph.node[a]
        return node['primary'] if node else a

    def map_node(node, data):
        return (data['primary'], dict(node_id=data['node_id'])) if data else (node, dict())

    digraph = nx.MultiDiGraph()
    digraph.add_nodes_from(map(map_node, *zip(*graph.nodes_iter(data=True))))
    digraph.add_edges_from(map(lambda a, b, data: (f(a), f(b), data), *zip(*graph.edges_iter(data=True))))

    return digraph


def merge_nodes(graph):
    def merge_edges(data):
        tq = min(map(lambda d: d['tq'], data))
        vpn = all(map(lambda d: d.get('vpn', False), data))
        return dict(tq=tq, vpn=vpn)

    multigraph = to_multigraph(graph)
    digraph = nx.DiGraph()
    digraph.add_nodes_from(multigraph.nodes_iter(data=True))
    edges = chain.from_iterable([[(e, d, merge_edges(multigraph[e][d].values()))
                                  for d in multigraph[e]] for e in multigraph])
    digraph.add_edges_from(edges)

    return digraph


def to_undirected(graph):
    multigraph = nx.MultiGraph()
    multigraph.add_nodes_from(graph.nodes_iter(data=True))
    multigraph.add_edges_from(graph.edges_iter(data=True))

    def merge_edges(data):
        tq = max(map(lambda d: d['tq'], data))
        vpn = all(map(lambda d: d.get('vpn', False), data))
        return dict(tq=tq, vpn=vpn, bidirect=len(data) == 2)

    graph = nx.Graph()
    graph.add_nodes_from(multigraph.nodes_iter(data=True))
    edges = chain.from_iterable([[(e, d, merge_edges(multigraph[e][d].values()))
                                  for d in multigraph[e]] for e in multigraph])
    graph.add_edges_from(edges)

    return graph