#!/usr/bin/env bash

# - Script generates webalizer webstatistics
# -
# - usage: generate_webstats.sh [<site1> [<site2> ... ]] 
# -
# - Webstatistics for the given sites will be created, where 'site<n>' must match
# - the 'HostName' parameter of the webalizer configuration. 
# -
# - If no commandline is parameter given, statistics for all sites (which has a webalizer 
# - configuration) will be generated.
# - 

_src_base_dir="$(dirname $(realpath $0))"
conf_file="${_src_base_dir}/conf/webalizer.conf"

tmp_dir="$(mktemp -d)"
log_file="$(mktemp)"



# -------------
# - Functions
# -------------

clean_up() {

   # Perform program exit housekeeping
   rm -f "$log_file"
   rm -rf "$tmp_dir"
   if $terminal ; then
      echo ""
   fi
   exit $1
}

## - Check if a given array (parameter 2) contains a given string (parameter 1)
## -
containsElement () {
   local e
   for e in "${@:2}"; do [[ "$e" == "$1" ]] && return 0; done
   return 1
}

echononl(){
   if $terminal ; then
      echo X\\c > /tmp/shprompt$$
      if [ `wc -c /tmp/shprompt$$ | awk '{print $1}'` -eq 1 ]; then
         echo -e -n "$*\\c" 1>&2
      else
         echo -e -n "$*" 1>&2
      fi
      rm /tmp/shprompt$$
   fi
}
info (){
   if $terminal ; then
      echo ""
      echo -e "   [ \033[32m\033[1mInfo\033[m ]: $*"
      echo ""
   fi
}
warn (){
   if $terminal ; then
      echo ""
      echo -e "   [ \033[33m\033[1mWarning\033[m ]: $*"
      echo ""
   else
      echo ""
      echo "[ Warning ]: $*"
      echo ""
   fi
}
error(){
   echo ""
   if $terminal ; then
      echo -e "   [ \033[31m\033[1mFehler\033[m ]: $*"
   else
      echo "[ Error ]: $*"
   fi
   echo ""
}


echo_done() {
   if $terminal ; then
      echo -e "\033[75G[ \033[32mdone\033[m ]"
   fi
}

echo_failed(){
   if $terminal ; then
      echo -e "\033[75G[ \033[1;31mfailed\033[m ]"
   fi
}
echo_skipped() {
   if $terminal ; then
      echo -e "\033[75G[ \033[37mskipped\033[m ]"
   fi
}



# -------------
# --- Check some prerequisites
# -------------

# - Running in a terminal?
# -
if [[ -t 1 ]] ; then
      terminal=true
else
   terminal=false
fi

declare -a given_site_arr

# - Is a site given on command line?
# - 
if [[ $# -gt 0 ]]; then
   for _site in "$@" ; do
      given_site_arr+=("$_site")
   done
fi


# -------------
# --- Default values
# -------------

DEFAULT_WEBALSIZER_BINARY="/usr/local/webalizer/bin/webalizer"
DEFAULT_WEBALSIZER_CONF_DIR="/usr/local/webalizer/etc"

# -------------
# --- Read Configurations from $conf_file
# -------------

if [[ -f "$conf_file" ]]; then
   source "$conf_file"
fi

[[ -n "$WEBALSIZER_BINARY" ]] || WEBALSIZER_BINARY="$DEFAULT_WEBALSIZER_BINARY"
[[ -n "$WEBALSIZER_CONF_DIR" ]] || WEBALSIZER_CONF_DIR="$DEFAULT_WEBALSIZER_CONF_DIR"

_CACHE_FILE="${tmp_dir}/dns_cache.db"


# - Check if script was invoked from logrotation script
# -
# - Note: Its the parent of the parent
# -
_stat=($(</proc/$PPID/stat))
_PPPID="${_stat[3]}"
_COMMAND="$(ps -o cmd= $_PPPID)"
if [[ "$_COMMAND" =~ /usr/sbin/logrotate ]]; then
   invoked_from_logrotate=true
else
   invoked_from_logrotate=false
fi

info "Generate web-statistics at host \033[1m$(hostname -f)\033[m"

while IFS='' read -r -d '' _conf_file ; do

   _websites_log_file="$(grep -E "^\s*LogFile" $_conf_file | awk '{print$2}')"
   _site="$(grep -e "^\s*HostName" $_conf_file | awk '{print$2}')"


   if [[ ${#given_site_arr[@]} -gt 0 ]] ; then
       containsElement "$_site" "${given_site_arr[@]}" || continue
   fi
   

   # - Warn if script was called from logrotation script
   # -
   if $invoked_from_logrotate ; then
      if [[ "${_websites_log_file##*.}" = "log" ]]; then
         warn "${_site}: Maybe you are going to inspect an empty - because just even rotated - logfile."
      fi
   fi

   echononl "  Generate statistics for site '${_site}'.."
   rm -f "$_CACHE_FILE"
   
   # - Take care log file is not empty
   # -
   if [[ ! -s "${_websites_log_file}" ]] ; then
      echo_skipped
      if ! $terminal ; then
         warn "No web-statistics for site '${_site}' generated!
             LogFile '${_websites_log_file}' not found or empty."
      fi
      continue
   fi

   $WEBALSIZER_BINARY  -Q  -p  -M4  -N20 -D "$_CACHE_FILE" -c "${_conf_file}" > $log_file 2>&1
   if [[ $? -ne 0 ]]; then
      if ! $terminal ; then
         echo "[ Error ]: Generatin webstatistics for site '${_site}' failed!"
      fi
      echo_failed
      error "$(cat "$log_file")"
   else
      echo_done
   fi

done < <(find "${WEBALSIZER_CONF_DIR}" -maxdepth 1 -type f -name "*.conf" -print0)

clean_up 0