#!/bin/bash
#
# vmail-stack
# https://git.stack-source.com/msb/vmail-stack
# MIT License Copyright (c) 2021 Matthew Saunders Brown

# load config
source /usr/local/etc/vmail.conf

help()
{
  thisfilename=$(basename -- "$0")
  echo "$thisfilename"
  echo "Add email forward to vmail system"
  echo ""
  echo "usage: $thisfilename email forward_to [OPTIONS]"
  echo ""
  echo "  -h          Print this help."
  echo "  -l          Save Local (forward & keep local copy). 0 = no/off, 1 = yes/on. Default is 0."
  echo ""
  echo "              'email' and 'forward_to' should both be in full email address format."
  echo "              .e.g to have info@example.com delivered (forwarded) to joe@example.com do:"
  echo "              $thisfilename info@example.com joe@example.com"
  exit
}

# check for and set forward_to & email address & split email in to mbox (local part) & domain
if [ -n "$2" ]; then
  if [ $1 == "-h" ] || [ $2 == "-h" ]; then
    help
  else
    email=$1
    shift
    if [[ $email =~ "@" ]] ; then
      mbox=${email%@*}
      domain=${email##*@}
      if [ -z $mbox ] ; then
        echo "ERROR: No local part in $email."
        exit 1
      elif [ -z $domain ] ; then
        echo "ERROR: No domain in $email."
        exit 1
      elif ! vmail::validate_domain $domain; then
        echo "ERROR: $domain is not a valid domain name."
        exit 1
      fi
    else
      echo "ERROR: $email is not a valid email."
      exit 1
    fi
    forward_to=$1
    shift
    if [[ $forward_to =~ "@" ]] ; then
      forward_to_mbox=${forward_to%@*}
      forward_to_domain=${forward_to##*@}
      if [ -z $forward_to_mbox ] ; then
        echo "ERROR: No local part in $forward_to."
        exit 1
      elif [ -z $forward_to_domain ] ; then
        echo "ERROR: No domain in $forward_to."
        exit 1
      elif ! vmail::validate_domain $forward_to_domain; then
        echo "ERROR: $forward_to_domain is not a valid domain name."
        exit 1
      fi
    else
      echo "ERROR: $forward_to is not a valid email."
      exit 1
    fi
  fi
else
  help
fi

# set any options that were passed
while getopts "hl:" opt; do
  case "${opt}" in
    h )
      help
      exit;;
    l )
      save_local=${OPTARG}
      if [ "$save_local" != "0" ] && [ "$save_local" != "1" ]; then
        echo "ERROR: Invalid save local setting: -l $save_local."
        help
        exit 1
      fi
      ;;
    \? )
      echo "Invalid option: $OPTARG" 1>&2
      exit;;
    : )
      echo "Invalid option: $OPTARG requires an argument" 1>&2
      exit;;
  esac
done

# build query
dbcmd="mysql --defaults-extra-file=$MYSQL_CONNECTION_INFO_FILE"
dbcmdopts="-s -r -N -e"

# get mbox id, which also verfies that email address exists
dbquery="SELECT vm_mboxes.id FROM vm_mboxes, vm_domains WHERE vm_mboxes.mbox='$mbox' AND vm_mboxes.domain_id=vm_domains.id AND vm_domains.domain='$domain';"
mbox_id=`eval $dbcmd $dbcmdopts \"$dbquery\"`

if [ -z $mbox_id ]; then
  # mbox does not exist, can't create forward
  echo "ERROR: Address to Forward ($email) does not exist."
  exit 1
elif [ "$mbox_id" -gt '0' ]; then
  # verified mbox, check for existing forward
  dbquery="SELECT id FROM vm_forwards WHERE mbox_id='$mbox_id';"
  vm_forwards_id=`eval $dbcmd $dbcmdopts \"$dbquery\"`
  if [ -z $vm_forwards_id ]; then
    # existing forward does not exist, add it now
    dbcommand="INSERT INTO vm_forwards SET mbox_id='$mbox_id', forward_to='$forward_to'"
    if [ -n $save_local ]; then
      dbquery="$dbquery, save_local='$save_local'"
    fi
    echo $dbcmd $dbcmdopts \"$dbquery;\"
  else
    echo "ERROR: Forward for $email already exists. To change either del then add or use mod script."
    exit 1
  fi
else
  # db query error
  echo "ERROR: System error querying vmail database."
  exit 1
fi