import referencni
from referencni import reference
from ocesavac import ocesat

ABECEDA = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ'

def posun(char, pos=1):
    if 65 <= ord(char) < 91 - pos:
        return chr(ord(char) + pos)
    if ord(char) < 91 and ord(char) >= 91 - pos:
        return chr(ord(char) + pos - 26)
    else:
        return char

def vsechny(zprava):
    posunuty = zprava.upper()
    analyza = []
    for i in range(26):
        posunuty = map(posun, posunuty)
        analyza.append(''.join(posunuty))
    return analyza

def eu_vzdalenost(v1, v2):
    return sum([(x - y)**2 for (x, y) in zip(v1, v2)])

def nejlepsi(text):
    ref = referencni.nacti('bref')
    freq = dict()
    for char in ocesat(text, False):
        freq[char] = freq.get(char, 0) + 1
    celkem = sum(freq.values())
    frekv = [float(freq.get(char, 0))/celkem for char in ABECEDA]
    vzdalenost = eu_vzdalenost(frekv, ref.frekvence)
    posunuti = 0
    for i in range(1, 26):
        frekv = [frekv[25]] + frekv[:-1]
        v2 = eu_vzdalenost(frekv, ref.frekvence)
        if v2 < vzdalenost:
            vzdalenost = v2
            posunuti = i
    return (posunuti, ''.join([posun(char, posunuti) for char in text.upper()]))