#!/bin/bash

# ============= FUTURE YUNOHOST HELPER =============
# Delete a file checksum from the app settings
#
# $app should be defined when calling this helper
#
# usage: ynh_remove_file_checksum file
# | arg: file - The file for which the checksum will be deleted
ynh_delete_file_checksum () {
	local checksum_setting_name=checksum_${1//[\/ ]/_}	# Replace all '/' and ' ' by '_'
	ynh_app_setting_delete $app $checksum_setting_name
}


#=================================================
# EXPERIMENTAL HELPERS
#=================================================

# Create a dedicated fail2ban config (jail and filter conf files)
#
# usage: ynh_add_fail2ban_config log_file filter [max_retry [ports]]
# | arg: log_file - Log file to be checked by fail2ban
# | arg: failregex - Failregex to be looked for by fail2ban
# | arg: max_retry - Maximum number of retries allowed before banning IP address - default: 3
# | arg: ports - Ports blocked for a banned IP address - default: http,https
ynh_add_fail2ban_config () {
   # Process parameters
   logpath=$1
   failregex=$2
   max_retry=${3:-3}
   ports=${4:-http,https}
   
  test -n "$logpath" || ynh_die "ynh_add_fail2ban_config expects a logfile path as first argument and received nothing."
  test -n "$failregex" || ynh_die "ynh_add_fail2ban_config expects a failure regex as second argument and received nothing."
  
  finalfail2banjailconf="/etc/fail2ban/jail.d/$app.conf"
  finalfail2banfilterconf="/etc/fail2ban/filter.d/$app.conf"
  ynh_backup_if_checksum_is_different "$finalfail2banjailconf" 1
  ynh_backup_if_checksum_is_different "$finalfail2banfilterconf" 1
  
  sudo tee $finalfail2banjailconf <<EOF
[$app]
enabled = true
port = $ports
filter = $app
logpath = $logpath
maxretry = $max_retry
EOF

  sudo tee $finalfail2banfilterconf <<EOF
[INCLUDES]
before = common.conf
[Definition]
failregex = $failregex
ignoreregex =
EOF

  ynh_store_file_checksum "$finalfail2banjailconf"
  ynh_store_file_checksum "$finalfail2banfilterconf"
  
  systemctl restart fail2ban
  local fail2ban_error="$(journalctl -u fail2ban | tail -n50 | grep "WARNING.*$app.*")"
  if [ -n "$fail2ban_error" ]
  then
    echo "[ERR] Fail2ban failed to load the jail for $app" >&2
    echo "WARNING${fail2ban_error#*WARNING}" >&2
  fi
}

# Remove the dedicated fail2ban config (jail and filter conf files)
#
# usage: ynh_remove_fail2ban_config
ynh_remove_fail2ban_config () {
  ynh_secure_remove "/etc/fail2ban/jail.d/$app.conf"
  ynh_secure_remove "/etc/fail2ban/filter.d/$app.conf"
  sudo systemctl restart fail2ban
}