########################################################################
#  Copyright (C) 2015 Max Mehl <mail@mehl.mx>
########################################################################
#  
#  This program is free software: you can redistribute it and/or modify
#  it under the terms of the GNU General Public License as published by
#  the Free Software Foundation, either version 3 of the License, or
#  (at your option) any later version.
#  
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#  
#  You should have received a copy of the GNU General Public License
#  along with this program.  If not, see <http://www.gnu.org/licenses/>.
#  
########################################################################
#  
#  This script handles calls from submit.php.
#  It checks the validity of usernames, executes basic command
#  When password entries are required, it starts the respective python
#   scripts
#  
########################################################################
#!/bin/bash

# Test if config.cfg exists and set needed variables
if [ ! -e config.cfg ]; then echo "Missing config.cfg file. Edit and rename config.cfg.sample"; exit 1; fi
source config.cfg

ACTION=$1     # adduser, changepw, listusers, userdetail, deluser, sizeall, sizeuser, viewdata
USER=$2
PASSFILE=$3   # $3 is a file containing the password
PASS=$(cat "$3")

## FUNCTIONS
function checkaction {
  REGEX="^adduser$|^changepw$|^listusers$|^userdetail$|^deluser$|^sizeall$|^sizeuser$|^viewdata$"
  if [[ $1 =~ $REGEX ]]; then 
    echo "true" 
  else
    echo "false"
  fi
}

function checkuser {
  REGEX="^[A-Za-z0-9._+-]+$"    # Allowed symbols
  if [[ $1 =~ $REGEX ]]; then 
    echo "true" 
  else
    echo "false"
  fi
}

function checkpass {
  REGEX="[ 'x\\]"   # Not allowed symbols
  if [[ ! "$1" =~ $REGEX ]]; then 
    echo "true" 
  else
    echo "false"
  fi
}

function userexists {
  STATUS=$(listvdomain | cut -d" " -f 1 | sed '1d' | grep -q "^$1$" ; echo $?)
  if [ $STATUS == 0 ]; then
    echo "true"
  else
    echo "false"
  fi
}

function mailsend { 
  TOEMAIL="$TOEMAIL";
  FREMAIL="$FREMAIL";
  SUBJECT="[$DOMAIN] $1";
  MSGBODY1="$2"
  MSGBODY2="$3"

  printf '%s\n' "From: $FREMAIL
To: $TOEMAIL
Reply-To: $FREMAIL
Subject: $SUBJECT

$MSGBODY1

$MSGBODY2
" > $MAILTMP
  cat $MAILTMP | "$SENDMAILPATH" -t;
  rm $MAILTMP;
}

function mailsendenc {
  
  if [ ! -e $SSLKEY ]; then
    #echo "Encryption key \"$SSLKEY\" is not available. Aborting."
    #exit 1
    
    openssl genrsa -out $SSLKEY 2048
  fi
  
  TOEMAIL="$TOEMAIL";
  FREMAIL="$FREMAIL";
  SUBJECT="[$DOMAIN] $1";
  MSGBODY1="$2"
  BOUNDARY="ZZafgwejwepfgkl.9453x1q"
  ATTACHMENT=$(echo $3 | openssl rsautl -inkey $SSLKEY -encrypt | base64)

printf '%s\n' "From: $FREMAIL
To: $TOEMAIL
Reply-To: $FREMAIL
Subject: $SUBJECT
Mime-Version: 1.0
Content-Type: multipart/mixed; boundary=\"$BOUNDARY\"

--${BOUNDARY}
Content-Type: text/plain; charset=\"us-ascii\"
Content-Transfer-Encoding: 7bit
Content-Disposition: inline

$MSGBODY1

Upload the attached encrypted file to your Account Administration Panel 
in order to see sensitive details. Please visit the section \"Decrypt 
system email\" for more details.

--${BOUNDARY}
Content-Type: text/plain
Content-Transfer-Encoding: 7bit
Content-Disposition: attachment; filename=\"message.txt.crypt\"

$ATTACHMENT

--${BOUNDARY}

" > $MAILTMP
  cat $MAILTMP | "$SENDMAILPATH" -t;
  rm $MAILTMP;
}

function notesdelete {  # $1=$USER
  USER="$1"
  # Extract Mail part | exclude LEAD and TAIL | delete user
  sed -n "/$LEAD/,/$TAIL/ p" $NOTES | grep -v "$LEAD\|$TAIL" | sed "/User:[ \t]*$USER$/,+2d" > $NOTESTMP
  # Put edited part in between $LEAD and $TAIL again
  sed -i "/$LEAD/,/$TAIL/{ /$LEAD/{p; r $NOTESTMP
          }; /$TAIL/p; d }" $NOTES
  rm $NOTESTMP
}

function notesinsert {
  # Update datasheet (add new entry in Email section)
  USER=$1
  PASSFILE=$2
  
  # Create temporary file from $PASSFILE
  sed -E "s/(.*)/User:     $USER\nPass:     \1\n/" $PASSFILE > .$PASSFILE.tmp
  
  # Insert this edited file into the datasheet
  sed -i "/$TAIL/ {
         h
         r .$PASSFILE.tmp
         g
         N
     }" $NOTES

  #rm .$PASSFILE.tmp
  
#  sed -i "/$TAIL/i User:     $USER\nPass:     $PASS\n" $NOTES
}

## FIRST CHECKS
if ! $(checkaction "$ACTION"); then
  echo "No valid action chosen"
  exit 1
fi


# # # # #
# ADDING USER
# # # # #
if [ "$ACTION" == "adduser" ]; then
  echo "Adding new Email user..."
  echo
  
  if ! $(checkuser "$USER"); then
    echo "Username \"$USER\" invalid"
    exit 1
  fi
  
  if $(userexists "$USER"); then
    echo "User \"$USER\" does already exist!"
    exit 1
  fi
  
  if ! $(checkpass "$PASS"); then
    echo "Password \"$PASS\" invalid"
    exit 1
  fi
  
  python adduser.py "$USER" "$PASSFILE"
  
  if [ $? == 0 ]; then
    # Send infomail
    $MAILTYPE "New Email account created" \
             "A new Email account has been created." \
             "User: $USER | Password: $PASS"
    
    LEAD='## > EMAIL'
    TAIL='## < EMAIL'
    notesinsert "$USER" "$PASSFILE"
  
  fi
fi # /adduser

# # # # #
# CHANGE PASSWORD
# # # # #
if [ "$ACTION" == "changepw" ]; then
  echo "Changing password of Email account..."
  echo
  
  if ! $(userexists "$USER"); then
    echo "User \"$USER\" does not exist!"
    exit 1
  fi
  
  if ! $(checkpass "$PASS"); then
    echo "Password \"$PASS\" invalid"
    exit 1
  fi
  
  python changepw.py "$USER" "$PASSFILE"
  
  if [ $? == 0 ]; then
    # Send infomail
    $MAILTYPE "Email password changed" \
             "An Email account password has been changed." \
             "User: $USER | New Password: $PASS"

    # Update datasheet (delete entry in Email section and add a new one with the new password)
    # In fact a combination of deluser and adduser
    LEAD='## > EMAIL'
    TAIL='## < EMAIL'
    
    notesdelete "$USER" 
    notesinsert "$USER" "$PASSFILE"
    
  fi
fi # /changepw

# # # # #
# LIST USERS
# # # # #
if [ "$ACTION" == "listusers" ]; then
  echo "Listing all Email accounts..."
  echo
  
  listvdomain | column -s $' ' -t
  
fi # /listusers

# # # # #
# SIZE ALL USERS
# # # # #
if [ "$ACTION" == "sizeall" ]; then
  echo "Calculate total size of all Email accounts..."
  echo
  
  du -sBM ~/users/* | sed -e "s:/home/$SYSUSER/users/::g"
  
fi # /sizeall

# # # # #
# VIEW DATASHEET
# # # # #
if [ "$ACTION" == "viewdata" ]; then
  echo "Extracting data sheet..."
  echo
  
  cat $NOTES
  
fi # /viewdata

# # # # #
# SIZE USER
# # # # #
if [ "$ACTION" == "sizeuser" ]; then
  echo "Calculate size of all folders of an Email account..."
  echo
  
  # Show size in MB, strip long paths, strip tmp and new folders, rename .INBOX cur-folder
  du -BM ~/users/"$USER" | sed -e "s:/home/$SYSUSER/users/$USER/::g" | grep -v "/cur$\|new$\|tmp$" | sed "s:cur$:.INBOX:" | grep -v "/home/$SYSUSER/users/$USER" | sort -nr
  
fi # /sizeuser

# # # # #
# USER DETAIL
# # # # #
if [ "$ACTION" == "userdetail" ]; then
  echo "Extracting details of Email account..."
  echo
  
  if ! $(userexists "$USER"); then
    echo "User \"$USER\" does not exist!"
    exit 1
  fi
  
  dumpvuser "$USER" | column -s $' ' -t
  
fi # /userdetail

# # # # #
# DELETE USER
# # # # #
if [ "$ACTION" == "deluser" ]; then
  echo "Extracting details of Email account..."
  echo
  
  if ! $(userexists "$USER"); then
    echo "User \"$USER\" does not exist!"
    exit 1
  fi
  
  vdeluser "$USER"
  
  if [ $? == 0 ]; then
    # Send infomail
    $MAILTYPE "Email account deleted" \
             "An Email account has been deleted." \
             "User: $USER"
    
    # Update datasheet (delete entry in Email section)
    LEAD='## > EMAIL'
    TAIL='## < EMAIL'
    
    notesdelete "$USER" 
  
  fi
fi # /deluser