Something

#!/bin/bash
#give sub name, wanted
parse_sub () {
  sub=$1
  parse_sub="${sub###*.}"   #ei.
  sub="${sub//$parse_sub/}"
  eposide="${sub#*E}"
  season="${sub//episode/}"
  season="${season#*S}"
  if [[ $2==2 ]]
  then
     return $season
  else
     return $episode
  fi
}
 
#give avi name, wanted
parse_avi () {
    avi=$1
    parse_avi="${avi##*_-_}" #ei
    avi="${avi//$parse_avi/}"
    avi="${avi#*_-_}"  #ei
    avi="${avi//_-_/}" #ei
    episode="${avi#*x}"
    season="${avi//$episode}"
    season="${season//x/}"
    echo before if episode is $episode                                   
    if [[ $2 = 2 ]]
    then 
      return $season
    else
      return $episode
    fi
}

files=$(ls *sub | wc -l) 
echo $files
while [[ $files > 0 ]] 
do 
  if [[ $files != 0 ]] 
  then
    let "files -= 1"
  fi
  read -r -a Words <<< $(ls *avi)
  read -r -a Subs <<< $(ls *sub)
  avi=${Words[$files]}
  sub=${Subs[$files]}  
  #parsitaan vähäc
  parse_sub $sub 2 #season from sub
  sub_season=$?
  parse_sub $sub 1 #episode from sub
  sub_episode=$?
  parse_avi $avi 2 #season from avi
  avi_season=$?
  parse_avi $avi 1 #episode from avi
  avi_episode=$?
#echo avi episode is $avi_episode
#echo avi season is $avi_season
#echo sub season is $sub_season
#echo sub episode is $sub_episode
done