import bs4, os, re, csv

pattern = r'.+\.xml$'
folder_name = 'spiskovi'

path = os.path.join( '.', folder_name )
    
os.chdir( path )
files = os.listdir()

if files is []:
    print("Folder je prazan!")
    exit()

regex = re.compile( pattern )
groups = []
groups_info = []

files.sort()

for file in files:
     reObj = regex.search( file )
     if reObj is not None:
         groups += [ reObj.group() ]
         
for group_name in groups:
    group_file = open( group_name, 'r' )
    group = bs4.BeautifulSoup( group_file, features="html.parser" )
    group_file.close()

    students = group.select("student")
    if students == []:
        continue
    studenti_info = dict()
    for student in students:
        ime = student.find( "ime" ).get_text()
        prezime = student.find( "prezime" ).get_text()
        
        ocene =student.find("ocene")
        lista_ocena = ocene.select('ocena')
        broj_ocena = len( lista_ocena )
        prosek = -1
        if broj_ocena is not 0:
            lista_ocena = list( map( lambda x: int(x.get_text()), lista_ocena ) )
            prosek = sum( lista_ocena ) / broj_ocena
        
        indeks = student.find( "indeks" ).get_text()
        if studenti_info.get( indeks ) == None:
            studenti_info[ indeks ] = ( ime, prezime, prosek, group_name[:-4] )
        else:
            print("Student sa indeksom %s je vec unet!" % indeks )
            
    groups_info += [ studenti_info ]

polja = [ 'Ime', 'Prezime', 'Indeks', 'Prosek', 'Grupa' ]    
najbolji_file = open('Pera.csv', 'w', newline = '' )
najbolji_writer = csv.writer( najbolji_file )
najbolji_writer.writerow( polja )

for group_info in groups_info:
    items = list( group_info.items() )
    items.sort( key = lambda x: x[1][2])
    
    najbolji = list( items[-1][1][:2] ) + [ items[-1][0] ] + list( items[-1][1][2:] )
    najbolji_writer.writerow( najbolji )

najbolji_file.close()
os.chdir('..')