module ia32/elf/begin.sts
module ia32/float/float.sts
module cipher.sts
module keygen.sts
module freq.sts

[ sd 0 swap drop ]

defword nicedist
    3e9eb852 float_fload
exit

defword calcdist ; distance from ideal as sqrt sum square diff
    1b ref as calcdist.textfr
    local calcdist.fr
    0 do dup 1a = until
        dup word_size mul dup dup
                calcdist.fr + @ float_fload
                calcdist.textfr + @ float_fload
            float_sub float_fstore dup float_fload float_fload
        float_mul float_fstore swap calcdist.fr + !
    1 + od
    0 do dup 19 = until
        swap float_fload swap float_fload float_add float_fstore swap
    1 + od drop
    float_fload float_sqrt nicedist float_less
exit

defword checktext
    as checktext.length
    local checktext.text
        ; Count frequencies:
    ; 26 latin letters:
    0 0 0 0 0  0 0 0 0 0  0 0 0
    0 0 0 0 0  0 0 0 0 0  0 0 0 local checktext.fr
    ; count how much of each letter is in text:
    0 local checktext.count
    checktext.length do 1 -
        dup word_size mul checktext.text + @
        dup dup 'z' > 0 = swap 'a' < 0 = mul if
            dup 'z' swap - word_size mul checktext.fr + dup @ 1 + swap !
            checktext.count @ 1 + checktext.count !
        fi dup dup 'Z' > 0 = swap 'A' < 0 = mul if
            dup 'Z' swap - word_size mul checktext.fr + dup @ 1 + swap !
            checktext.count @ 1 + checktext.count !
        fi dup dup 8 > 0 = swap 1 < 0 = mul if drop drop drop
            drop drop drop drop drop  drop drop drop drop drop  drop drop drop
            drop drop drop drop drop  drop drop drop drop drop  drop drop drop
        0 exit fi dup dup 1f > 0 = swap e < 0 = mul if drop drop drop
            drop drop drop drop drop  drop drop drop drop drop  drop drop drop
            drop drop drop drop drop  drop drop drop drop drop  drop drop drop
        0 exit fi drop
    dup 0 = untilod drop
; ZERO DIVISION SHALL NOT PASS
checktext.count 0 = if drop
    drop drop drop drop drop  drop drop drop drop drop  drop drop drop
    drop drop drop drop drop  drop drop drop drop drop  drop drop drop
0 exit fi
    ; normalize:
    0 do dup 1a = until
            dup word_size mul checktext.fr + dup @ float_iload
            checktext.count @ float_iload
        float_div float_fstore swap !
    1 + od drop
        ; Decide if text is real:
    freq_eng calcdist if 1 else
    0 fi
        ; Remove frequencies from stack:
    sd
    sd sd sd sd sd  sd sd sd sd sd  sd sd sd
    sd sd sd sd sd  sd sd sd sd sd  sd sd sd
exit

set_entry float_init ; this is program with floats
    ; read file into stack
    0 do sys_read 0 = until
        swap 1 +
    od drop as length
    local ciphertext

    0 ; initial key is empty
    do
        ; generate next key to try
        keygen as keylen local key

        ; decipher text (length is the same as for ciphertext)
        keylen 1 - length do 1 -
            as textpos local pos
                textpos word_size mul ciphertext + @
                key
                keylen
                pos
            cipher
            swap textpos
        dup 0 = untilod drop drop
        local plaintext

        ; check deciphering attempt, exit if Ok or keylen = max (2)
    keylen 2 = if eeeee else length checktext fi dup until drop
        ; else remove the text from stack and place keylen back
        0 do dup length = until
            swap drop 1 +
        od drop keylen
    od as langcode drop

    ; output language
    langcode 1 = if
        'e' sys_write_err
        'n' sys_write_err
        'g' sys_write_err
        'l' sys_write_err
        'i' sys_write_err
        's' sys_write_err
        'h' sys_write_err
    fi langcode 2 = if
        'd' sys_write_err
        'u' sys_write_err
        't' sys_write_err
        'c' sys_write_err
        'h' sys_write_err
    fi langcode 3 = if
        'g' sys_write_err
        'e' sys_write_err
        'r' sys_write_err
        'm' sys_write_err
        'a' sys_write_err
        'n' sys_write_err
    fi langcode 4 = if
        'f' sys_write_err
        'r' sys_write_err
        'e' sys_write_err
        'n' sys_write_err
        'c' sys_write_err
        'h' sys_write_err
    fi langcode 5 = if
        's' sys_write_err
        'p' sys_write_err
        'a' sys_write_err
        'n' sys_write_err
        'i' sys_write_err
        's' sys_write_err
        'h' sys_write_err
    fi langcode 6 = if
        'i' sys_write_err
        't' sys_write_err
        'a' sys_write_err
        'l' sys_write_err
        'i' sys_write_err
        'a' sys_write_err
        'n' sys_write_err
    fi langcode eeeee = if
        'e' sys_write_err
        'r' sys_write_err
        'r' sys_write_err
        'o' sys_write_err
        'r' sys_write_err
    fi newline sys_write_err

    ; output text
    length do 1 -
        swap sys_write
    dup 0 = untilod drop

    ; output key
    keylen do 1 -
        swap sys_write_err
    dup 0 = untilod drop newline sys_write_err
sys_exit

module ia32/elf/end.sts