#-----------------------------------------------------------
# Parameters:   plaintext (string)
#               key (b,r): (int,int)
# Return:       ciphertext (string)
# Description:  break plaintext into blocks of size b
#               rotate each block r times to the left
#-----------------------------------------------------------
def e_blockRotate(plaintext,key):

    #change to the one which removes non alpha
    key = adjustKey_blockRotate(key)
    ciphertext = ''
    b = key[0]
    r = key[1]

    nonAlpha = get_nonalpha(plaintext)
    plaintext = remove_nonalpha(plaintext)

    blocks = text_to_blocks(plaintext, b)

    size = len(blocks[-1])
    while size <(b):
        blocks[-1]+='q'
        size+=1

    i = 0
    while i<len(blocks):
        ciphertext+=utilities_A2.shift_string(blocks[i], r, 'l')
        i+=1

    ciphertext = insert_nonalpha(ciphertext,nonAlpha)
    return ciphertext


#-----------------------------------------------------------
# Parameters:   ciphertext (string)
#               key (b,r): (int,int)
# Return:       plaintext (string)
# Description:  Decryption using Block Rotate Cipher
#-----------------------------------------------------------
def d_blockRotate(ciphertext,key):
    i = adjustKey_blockRotate(key)
    plaintext = ''
    a = i[0]
    w = i[1]
    alpha = get_nonalpha(ciphertext)

    modifiedText = ''
    for char in ciphertext:
        if char.isalpha():
            modifiedText += char

    block = text_to_blocks(modifiedText,a)
    r = 0
    while r < len(block):
        plaintext += utilities_A2.shift_string(block[r], w, 'r')
        r += 1

    plaintext = insert_nonalpha(plaintext, alpha)
    value = plaintext[-1]
    while(value == 'q'):
        plaintext = plaintext[:len(plaintext)-1]
        value = plaintext[-1]
    return plaintext

#-----------------------------------------------------------
# Parameters:   ciphertext (string)
#               b1 (int): starting block size
#               b2 (int): end block size
# Return:       plaintext,key
# Description:  Cryptanalysis of Block Rotate Cipher
#               Returns plaintext and key (r,b)
#               Attempts block sizes from b1 to b2 (inclusive)
#               Prints number of attempts
#-----------------------------------------------------------
def cryptanalysis_blockRotate(ciphertext,b1,b2):
    # your code here
    attempts = 1
    for b in range(b1, b2+1):
        for i in range(b):
            testDecrypt = d_blockRotate(ciphertext, (b, i))
            if utilities_A2.is_plaintext(testDecrypt, "engmix.txt", .7):
                print("Key found after {:d} attempts".format(attempts))
                print("Key: ",(b,i))
                print("Plaintext:",testDecrypt)
                return testDecrypt, (b, i)
            else:
                attempts += 1
    print("Block Rotate Cryptanalysis Failed. No Key was found.")
    return "",(0,0)