"""
Authors: Peter Mawhorter, Indira Ruslanova
Consulted:
Date: 2022-3-3
Purpose: Example file for writing code to find distances to unexplored
nodes.
"""

# Import the library (note: it must be installed for this to work)
import networkx as nx


#---------------#
# Graph metrics #
#---------------#


def findUnknownDistances(graph, startName):
    """
    Given a graph and the name of a starting node, finds the distance
    from that starting node to each node whose name starts with 'unknown:'
    and returns a list of those distances.

    Distances are measured in terms of number of hops in the graph,
    which is just an integer.
    """
    # TODO: write this function :)
    distList = []
    unknownList = []
    #go through every node
    for node in graph:
        #check if it starts with "unknown"
        if node.startswith("unknown"):
            unknownNode = node
            #add to the unknownList if node starts with "unknown"
            unknownList.append(unknownNode)
    #for every unknown node in the list        
    for unknown in unknownList:
        try:
            #calculate the path
            listNodes = nx.shortest_path(G=graph, source=startName, target=unknown, weight=None, method="dijkstra")
        #except for when there is no path
        except:
            nx.exception.NetworkXNoPath
            continue
        #counter to keep track of how many nodes there are
        countNodes = 0
        #not counting the start node and the target node themselves
        listNodes.remove(startName)
        listNodes.remove(unknown)
        #count how many nodes there are
        for node in listNodes:
            countNodes+=1
        #add to list of distances between nodes
        distList.append(countNodes)
    return (distList)


#---------#
# Testing #
#---------#

# I put your code from last week into `exampleGraph.py` and the variable
# `example` contains the graph you built, plus a few nodes whose names
# start with 'unknown:'.
from exampleGraph import example # noqa

print("Distances to unknown points from node A:")
print(findUnknownDistances(example, 'A'))
print("Distances to unknown points from node C:")
print(findUnknownDistances(example, 'C'))
print("Distances to unknown points from node E:")
print(findUnknownDistances(example, 'E'))