#!/bin/bash

CURDIR=$(dirname "$(readlink -f "$0")")
source "$CURDIR"/shared-functions.so

# MAIL QUEUE ACTIONS
function send_mailqueue {   # send queued mails
  $MSMTP_LIST
  read -p "Send these queued mails? [Y/n]: " YN
  if [[ $YN =~ ^(Y|y|)$ ]]; then
    $MSMTP_RUN
  else
    echo "Not sending emails"
  fi
}
function list_mailqueue {   # list emails in queue only
  $MSMTP_LIST
}

# CHANGE ONLINE STATUS
function switch_conn {
  echo "Current connection status: $var_conn"
  read -p "Switch connection status? [Y/n]: " YN
  if [[ $YN =~ ^(Y|y|)$ ]]; then
    if [ "$var_conn" == "off" ]; then
      var_conn="on"
      echo "Connection status switched to \"on\""
    else
      var_conn="off"
      echo "Connection status switched to \"off\""
    fi
  else
    echo "Connection status not changed."
  fi
}

# SWITCH NAMESERVERS
function switch_ns {
  read -p "Switch nameservers? [Y/n]: " YN
  if [[ $YN =~ ^(Y|y|)$ ]]; then
    NS_SETS=$(echo "$NS" | grep -o "|" | wc -l)   # number of nameserver sets (separated by |)
    NS_SETS=$(expr $NS_SETS + 1)                  # add number +1 to correct count
    
    for ((i = 1; i <= $NS_SETS; i++)); do   # circle through all nameserver sets and number them
      NS_NAME[$i]=$(echo $NS | cut -d"|" -f$i | sed -E 's/(^.+?)\((.+?)\)/\1/')
      NS_VALUE[$i]=$(echo $NS | cut -d"|" -f$i | sed -E 's/(^.+?)\((.+?)\)/\2/')
      
      echo "$i. ${NS_NAME[$i]}"
    done
    
    NS_NAME[0]="auto"; NS_VALUE[0]=""
    echo "0. ${NS_NAME[0]} (DHCP-given)"
    
    # Choose nameserver number and verify selection
    OK=0
    while [ "$OK" != "1" ]; do
      echo; read -p "Type number of nameserver set: " i
      
      if [ "${NS_NAME[$i]}" == "" ]; then
        OK=0
        echo "A nameserver set with this number does not exist. Please choose again."
      else
        OK=1
        echo "Nameserver set switched to \"${NS_NAME[$i]}\". Please reconnect with NetworkManager to put the changes into effect."
      fi
    done
    
    # Set definite values
    NS_NAME=${NS_NAME[$i]}
    NS_VALUE=${NS_VALUE[$i]}
    
    NONS=$(echo "$NS_VALUE" | grep -o "," | wc -l)  # number of nameservers in chosen set
    NONS=$(expr $NONS + 1)
    
    echo "# Custom nameserver set: $NS_NAME" > /tmp/resolv_custom.conf  # write custom resolv config, which will be interpreted by "90-custom-resolvconf"
    
    for ((i = 1; i <= $NONS; i++)); do
      echo "nameserver $(echo $NS_VALUE | cut -d"," -f$i)" >> /tmp/resolv_custom.conf
    done
  
    var_ns=$NS_NAME   # save name of nameserver set for later update of status file
    
  fi  # / YN
}

# OPTION SCREEN
function exec {
  ACTIONS=("send mails in queue" "list mails in queue" "switch connection status [$var_conn]" "switch nameservers" "quit")
  PS3="Select action: "
  
  select action in "${ACTIONS[@]}"
  do
    echo  # empty line after selection
    case $REPLY in  # $REPLY takes the numbers which is nice
      1) # Show queue; ask for confirmation; if yes, send emails
      send_mailqueue
      break ;;
      2) # Show queue
      list_mailqueue
      break ;;
      3) # Switch online status
      switch_conn
      break ;;
      4) # Switch nameservers
      switch_ns
      break ;;
      5|"q") # exit silently, one can also press "q" instead of the number
      exit 0
      break ;;
    esac
  done
}

while :; do             # endless loop
  exec                  # interaction screen
  wtmp; source "$TMP"   # write changes back and load them
  echo                  # empty line
done