#!/usr/bin/env python
from __future__ import division
from nose.tools import *
import networkx as nx


def example1a_G():
    G = nx.Graph()
    G.add_node(1, percolation=0.1)
    G.add_node(2, percolation=0.2)
    G.add_node(3, percolation=0.2)
    G.add_node(4, percolation=0.2)
    G.add_node(5, percolation=0.3)
    G.add_node(6, percolation=0.2)
    G.add_node(7, percolation=0.5)
    G.add_node(8, percolation=0.5)
    G.add_edges_from([(1, 4), (2, 4), (3, 4), (4, 5), (5, 6), (6, 7), (6, 8)])
    return G


def example1b_G():
    G = nx.Graph()
    G.add_node(1, percolation=0.3)
    G.add_node(2, percolation=0.5)
    G.add_node(3, percolation=0.5)
    G.add_node(4, percolation=0.2)
    G.add_node(5, percolation=0.3)
    G.add_node(6, percolation=0.2)
    G.add_node(7, percolation=0.1)
    G.add_node(8, percolation=0.1)
    G.add_edges_from([(1, 4), (2, 4), (3, 4), (4, 5), (5, 6), (6, 7), (6, 8)])
    return G


class TestPercolationCentrality(object):
    def test_percolation_example1a(self):
        """percolation centrality: example 1a"""
        G = example1a_G()
        p = nx.percolation_centrality(G)
        p_answer = {4: 0.625, 6: 0.667}
        for n in p_answer:
            assert_almost_equal(p[n], p_answer[n], places=3)

    def test_percolation_example1b(self):
        """percolation centrality: example 1a"""
        G = example1b_G()
        p = nx.percolation_centrality(G)
        p_answer = {4: 0.825, 6: 0.4}
        for n in p_answer:
            assert_almost_equal(p[n], p_answer[n], places=3)

    def test_converge_to_betweenness(self):
        """percolation centrality: should converge to betweenness
        centrality when all nodes are percolated the same"""
        # taken from betweenness test test_florentine_families_graph
        G = nx.florentine_families_graph()
        b_answer =\
            {'Acciaiuoli':    0.000,
             'Albizzi':       0.212,
             'Barbadori':     0.093,
             'Bischeri':      0.104,
             'Castellani':    0.055,
             'Ginori':        0.000,
             'Guadagni':      0.255,
             'Lamberteschi':  0.000,
             'Medici':        0.522,
             'Pazzi':         0.000,
             'Peruzzi':       0.022,
             'Ridolfi':       0.114,
             'Salviati':      0.143,
             'Strozzi':       0.103,
             'Tornabuoni':    0.092}

        p_states = {k: 1.0 for k, v in b_answer.items()}
        p_answer = nx.percolation_centrality(G, states=p_states)
        for n in sorted(G):
            assert_almost_equal(p_answer[n], b_answer[n], places=3)

        p_states = {k: 0.3 for k, v in b_answer.items()}
        p_answer = nx.percolation_centrality(G, states=p_states)
        for n in sorted(G):
            assert_almost_equal(p_answer[n], b_answer[n], places=3)
