import arcpy, traceback, os, sys,time
import itertools as itt
scriptsPath=os.path.dirname(os.path.realpath(__file__))
os.chdir(scriptsPath)
import COMMON
sys.path.append(r'C:Usersfelix_pertzigerAppDataRoamingPythonPython27site-packages')
import networkx as nx
RATIO = int(arcpy.GetParameterAsText(0))

try:
    def showPyMessage():
        arcpy.AddMessage(str(time.ctime()) + " - " + message)
mxd = arcpy.mapping.MapDocument("CURRENT")
theT=COMMON.getTable(mxd)

theNodesLayer = COMMON.getInfoFromTable(theT,1)
theNodesLayer = COMMON.isLayerExist(mxd,theNodesLayer)

theLinksLayer = COMMON.getInfoFromTable(theT,9)
    theLinksLayer = COMMON.isLayerExist(mxd,theLinksLayer)
    arcpy.SelectLayerByAttribute_management(theLinksLayer, "CLEAR_SELECTION")
    linksFromI=COMMON.getInfoFromTable(theT,14)
    linksToI=COMMON.getInfoFromTable(theT,13)
    G=nx.Graph()
    arcpy.AddMessage("Adding links to graph")
    with arcpy.da.SearchCursor(theLinksLayer, (linksFromI,linksToI,"Times")) as cursor:
            for row in cursor:
                (f,t,c)=row
                G.add_edge(f,t,weight=c)
            del row, cursor
    pops=[]
    pops=arcpy.da.TableToNumPyArray(theNodesLayer,("P2013"))
    length0=nx.all_pairs_shortest_path_length(G)
    nNodes=len(pops)
    aBmNodes=[]
    aBig=xrange(nNodes)
    host=[-1]*nNodes
    while True:
            RATIO+=-1
            if RATIO==0:
                    break
            aBig = filter(lambda x: x not in aBmNodes, aBig)
            p=itt.combinations(aBig, 2)
            pMin=1000000
            small=[]
            for a in p:
                    S0,S1=0,0
                    for i in aBig:
                            p=pops[i][0]
                            p0=length0[a[0]][i]
                            p1=length0[a[1]][i]
                            if p0<p1:
                                    S0+=p
                            else:
                                    S1+=p
                    if S0!=0 and S1!=0:
                            sMin=min(S0,S1)
                            sMax=max(S0,S1)
                            df=abs(float(sMax)/sMin-RATIO)
                            if df<pMin:
                                    pMin=df
                                    aBest=a[:]
                                    arcpy.AddMessage('%s %i %i' %(aBest,sMax,sMin))
                            if df<0.005:
                                    break
            lSmall,lBig,S0,S1=[],[],0,0
            arcpy.AddMessage ('Ratio %i' %RATIO)
            for i in aBig:
                    p0=length0[aBest[0]][i]
                    p1=length0[aBest[1]][i]
                    if p0<p1:
                            lSmall.append(i)
                            S0+=p0
                    else:
                            lBig.append(i)
                            S1+=p1
            if S0<S1:
                    aBmNodes=lSmall[:]
                    for i in aBmNodes:
                            host[i]=aBest[0]
                    for i in lBig:
                            host[i]=aBest[1]
            else:
                    aBmNodes=lBig[:]
                    for i in aBmNodes:
                            host[i]=aBest[1]
                    for i in lSmall:
                            host[i]=aBest[0]

    with arcpy.da.UpdateCursor(theNodesLayer, "rcvnode") as cursor:
            i=0
            for row in cursor:
                    row[0]=host[i]
                    cursor.updateRow(row)
                    i+=1

            del row, cursor
except:
    message = "n*** PYTHON ERRORS *** "; showPyMessage()
    message = "Python Traceback Info: " + traceback.format_tb(sys.exc_info()[2])[0]; showPyMessage()
    message = "Python Error Info: " +  str(sys.exc_type)+ ": " + str(sys.exc_value) + "n"; showPyMessage()