# Man sure glad I can use SysMon to find this file without decrypting it manually, but don't tell OW - TJ
# IT WOULD""VE BEEEN NICE TO KNWO! - OW
# heh. oops - TJ

$Filename="decrypt.encrypted.ps1"
$Key=$args[0]
echo "key is $Key"

# safe filenaming so no one will overwrite a file accidentally -TJ
$end_thing = [System.IO.Path]::GetFileNameWithoutExtension($Filename)
$begin_thing = [System.IO.Path]::GetExtension($Filename)
$safe_filename = $end_thing + ".encrypted" + $begin_thing
$safe_path = [SYSTEM.IO.PATH]::Combine([System.IO.PATH]::GetDirectoryName($Filename), $safe_filename)

# TJ: while writing this, was inspired in part by https://github.com/watson/base64-emoji
function emojiTo64($str)
{
    $newstr = ""
    $convert_to_table = New-Object system.collections.hashtable
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,133,176))] = "A"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,133,177))] = "B"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]194,169))] = "C"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,152,160))] = "D"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,148,154))] = "E"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,152,135))] = "F"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,143,140,239,184,143,226,128,141,226,153,128,239,184,143))] = "G"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,144,177,226,128,141,240,159,146,187))] = "H"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,164,159))] = "I"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,142,131))] = "J"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,142,185))] = "K"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,148,172))] = "L"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,147,130))] = "M"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,153,143))] = "N"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,133,190))] = "O"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,133,191))] = "P"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,166,134))] = "Q"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,144,176))] = "R"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,143,185))] = "S"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,166,150))] = "T"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,155,184))] = "U"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,156,136))] = "V"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,152,171))] = "W"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,157,140))] = "X"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,146,185))] = "Y"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,164,170))] = "Z"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,148,160))] = "a"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,155,132))] = "b"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,147,134))] = "c"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,146,128))] = "d"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,154,161))] = "e"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,145,188))] = "f"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,143,140,239,184,143,226,128,141,226,153,130,239,184,143))] = "g"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,155,160))] = "h"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,132,185))] = "i"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,165,159))] = "j"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,166,182))] = "k"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,167,170))] = "l"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,167,153,226,128,141,226,153,130,239,184,143))] = "m"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,143,173))] = "n"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,173,149))] = "o"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,140,143))] = "p"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,167,175))] = "q"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]194,174))] = "r"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,141,182))] = "s"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,143,147))] = "t"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,145,189))] = "u"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,154,162))] = "v"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,152,169))] = "w"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,156,150))] = "x"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,159,168))] = "y"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,144,141))] = "z"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]48,239,184,143,226,131,163))] = "0"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]49,239,184,143,226,131,163))] = "1"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]50,239,184,143,226,131,163))] = "2"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]51,239,184,143,226,131,163))] = "3"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]52,239,184,143,226,131,163))] = "4"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]53,239,184,143,226,131,163))] = "5"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]54,239,184,143,226,131,163))] = "6"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]55,239,184,143,226,131,163))] = "7"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]56,239,184,143,226,131,163))] = "8"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]57,239,184,143,226,131,163))] = "9"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]226,143,175))] = "+"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,154,137))] = "/"
    $convert_to_table[[System.Text.Encoding]::UTF8.GetString(@([byte]240,159,144,142))] = "="

    $bytes = [system.Text.Encoding]::UTF8.GetBytes($str)
    for($i = 0; $i -lt $bytes.length; ) {
        $byte = $bytes[$i]
        if ($byte -eq 240) {

            if ($bytes[$($i+3)] -eq 153) {
                $offset = 12
            } elseif ($bytes[$($i+3)] -eq 140) {
                if ($bytes[$($i+12)] -eq 140) {
                    $offset = 16
                } else {
                    $offset = 15
                }
            } elseif ($bytes[$($i+3)] -eq 177) {
                if ($bytes[$($i+2)] -ne 133) {
                    $offset = 10
                } else {
                    $offset = 3
                }
            } else {
                $offset = 3
            }
            $subsection = $bytes[$i..$($i+$offset)]
            $emoji = [System.Text.Encoding]::UTF8.GetString($subsection)
            $newstr += $convert_to_table[$emoji]
            $i = $i+$offset+1
        } elseif ($byte -eq 194) {
            $subsection = $bytes[$i..$($i+1)]
            $emoji = [System.Text.Encoding]::UTF8.GetString($subsection)
            $newstr += $convert_to_table[$emoji]
            $i = $i+2
        } elseif ($byte -eq 226) {
            $subsection = $bytes[$i..$($i+2)]
            $emoji = [System.Text.Encoding]::UTF8.GetString($subsection)
            $newstr += $convert_to_table[$emoji]
            $i = $i+3
        } else {
            $subsection = $bytes[$i..$($i+6)]
            $emoji = [System.Text.Encoding]::UTF8.GetString($subsection)
            $newstr += $convert_to_table[$emoji]
            $i = $i+7
        }
    }
    return $newstr
}


# this is super secure - TJ
# i know, I tried for a while to break it, couldn't find a way - OW
# I moved the decrypt to another file, so no one could break it - TJ
# Good good good, now they'll never decrypt our customer credit card data - OW
function decrypt($str, $key)
{
    $bytes = [System.Convert]::FromBase64String($str)

    $key_bytes = $key.toCharArray()

    # vinginere cipher
    for($i = 0; $i -lt $bytes.length; $i++) {
        
        $key_byte = $key_bytes[$i % $key_bytes.length]
        $thing = $bytes[$i] 
        if ($thing -lt $key_byte) {
            $thing2 = ((($thing - $key_byte) % 256) + 256) % 256
        } else {
            $thing2 = ($thing - $key_byte) % 256
        }
        $bytes[$i] = $thing2
    }

    # Caesar to the rescue! to bad brutus got to him.
    for($i = 0; $i -lt $bytes.length; $i++) {
        if ($bytes[$i] -lt 3) {
            $bytes[$i] = ((($bytes[$i]- 3) % 256) + 256) % 256
        } else {
            $bytes[$i] = ($bytes[$i] - 3) % 256
        }
    }

    # shuffle
    if ($bytes.length % 2 -eq 0) {
        for($i = 0; $i -lt $($bytes.length / 2); $i++) {
            $cur_pos = $i * 2
            $orig = $bytes[$cur_pos..$($cur_pos + 2)]
            $bytes[$cur_pos + 1] = $orig[0]
            $bytes[$cur_pos + 0] = $orig[1]
        }
    }


    # add to bytes
    if ($bytes.length % 3 -eq 0) {
        for($i = 0; $i -lt $($bytes.length / 3); $i++) {
            $cur_pos = $i * 3
            $orig = $bytes[$cur_pos..$($cur_pos + 3)]


            if ($orig[0] -lt 7) {
                $orig[0] = ((($orig[0] - 7) % 256) + 256) % 256
            } else {
                $orig[0] = ($orig[0] - 7) % 256
            }

            if ($orig[1] -lt 3) {
                $orig[1] = ((($orig[1] - 3) % 256) + 256) % 256
            } else {
                $orig[1] = ($orig[1] - 3) % 256
            }

            if ($orig[2] -lt 1) {
                $orig[2] = ((($orig[2] - 1) % 256) + 256) % 256
            } else {
                $orig[2] = ($orig[2] - 1) % 256
            }

            $bytes[$cur_pos + 0] = $orig[0]
            $bytes[$cur_pos + 1] = $orig[1]
            $bytes[$cur_pos + 2] = $orig[2]
        }
    }




    # add and shuffle bytes
    if ($bytes.length % 5 -eq 0) {
        for($i = 0; $i -lt $($bytes.length / 5); $i++) {
            $cur_pos = $i * 5
            $orig = $bytes[$cur_pos..$($cur_pos + 5)]
            if ($orig[1] -lt 3) {
                $orig[1] = ((($orig[1] - 3) % 256) + 256) % 256
            } else {
                $orig[1] = ($orig[1] - 3) % 256
            }
            if ($orig[2] -lt 1) {
                $orig[2] = ((($orig[2] - 1) % 256) + 256) % 256
            } else {
                $orig[2] = ($orig[2] - 1) % 256
            }
            $orig[3] = ((($orig[3] - 0) % 256) + 256) % 256
            if ($orig[0] -lt 255) {
                $orig[4] = ((($orig[4] - 255) % 256) + 256) % 256
            } else {
                $orig[4] = ($orig[4] - 255) % 256
            }
            if ($orig[0] -lt 254) {
                $orig[0] = ((($orig[0] - 254) % 256) + 256) % 256
            } else {
                $orig[0] = ($orig[0] - 254) % 256
            }
            $bytes[$cur_pos + 0] = $orig[1]
            $bytes[$cur_pos + 1] = $orig[2]
            $bytes[$cur_pos + 2] = $orig[3]
            $bytes[$cur_pos + 3] = $orig[4]
            $bytes[$cur_pos + 4] = $orig[0]
        }
    }


    # shuffle bytes
    if ($bytes.length % 7 -eq 0) {
        for($i = 0; $i -lt $($bytes.length / 7); $i++) {
            $cur_pos = $i * 7
            $orig = $bytes[$cur_pos..$($cur_pos + 7)]
            # $bytes[$cur_pos + 0] = $orig[0]
            $bytes[$cur_pos + 2] = $orig[1]
            $bytes[$cur_pos + 1] = $orig[2]
            $bytes[$cur_pos + 6] = $orig[3]
            $bytes[$cur_pos + 5] = $orig[4]
            $bytes[$cur_pos + 4] = $orig[5]
            $bytes[$cur_pos + 3] = $orig[6]
        }
    }

    return [System.Text.Encoding]::UTF8.GetString($bytes)
}

$toencrypt=gc $Filename -Encoding utf8 -Raw
echo "file $Filename -> $safe_path w/$Key"
$plaintext=emojiTo64 "$toencrypt"
$plaintext=decrypt "$plaintext" "$Key"
echo $plaintext
SET-CONTENT -Force -PaTH $safe_path -NoNewLine -Encoding utf8 -Value "$plaintext"