#!/usr/bin/env bash

FILE=input
LEN=$( head -1 "$FILE" | sed -E 's/(.)/\1\ /g' | awk '{printf NF}' )

read -r -a MAP_ARRAY <<< "$( < "$FILE" sed -E 's/(.)/\1\ /g' | paste -s -d ' ' )"
read -r -a SHADOW_ARRAY <<< "$( < "$FILE" sed -E 's/(.)/\1\ /g' | paste -s -d ' ' )"
#printf "MAP_LEN: %s, NF: %s\n" "${#MAP_ARRAY[@]}" "$LEN" >&2

for CHAR in $( < "$FILE" grep -Eo '[^\.]' | sort -u | paste -s -d' ' )
do
  # Get indices for antennae
  LINE="$( 
    for (( i=0; i<${#MAP_ARRAY[@]}; i++ ))
    do
    if [[ ${MAP_ARRAY[i]} == "$CHAR" ]]
    then
      printf "%s " "$i"
    fi
    done
  )"
  #printf "%s\n" "$LINE" >&2
  read -r -a IDX_ARRAY <<< "$LINE"
  #printf "idx:  %s " "${IDX_ARRAY[@]}" >&2
  #printf "\n" >&2

  # Get all combinations
  for (( i=0; i<${#IDX_ARRAY[@]}-1; i++ ))
  do
    A=${IDX_ARRAY[i]}
    for (( j=i+1; j<${#IDX_ARRAY[@]}; j++ ))
    do
      B=${IDX_ARRAY[j]}
      DIFF=$(( B - A ))
      VDIFF=$(( (B / LEN) - (A / LEN) ))
      HEAD=$(( A - DIFF ))
      TAIL=$(( B + DIFF ))
      HEADVDIFF=$(( (A / LEN) - (HEAD / LEN) ))
      TAILVDIFF=$(( (TAIL / LEN) - (B / LEN) ))
      printf "char: %s, A: %s, B: %s, DIFF: %s, VDIFF: %s, HEAD: %s, HEADVDIFF: %s, TAIL: %s, TAILVDIFF: %s\n"  "$CHAR" "$A" "$B" "$DIFF" "$VDIFF" "$HEAD" "$HEADVDIFF" "$TAIL" "$TAILVDIFF" >&2
      # Check if out of bounds
      if [[ $HEAD -lt ${#MAP_ARRAY[@]} ]] && \
         [[ $HEAD -ge 0 ]] && \
         [[ $HEADVDIFF -eq $VDIFF ]]
      then
        SHADOW_ARRAY[HEAD]=X # Mark on shadow map
        echo $VALUE >> values
      fi
      if [[ $TAIL -lt ${#MAP_ARRAY[@]} ]] && \
         [[ $TAIL -ge 0 ]] && \
         [[ $TAILVDIFF -eq $VDIFF ]]
      then
        SHADOW_ARRAY[TAIL]=X # Mark on shadow map
        echo $VALUE >> values
      fi
    done
  done
  unset IDX_ARRAY

done
printf "%s" "${SHADOW_ARRAY[@]}" | fold -w "$LEN" | sed -E 's/(.)/\1\ /g'
printf "\n"
printf "%s" "${SHADOW_ARRAY[@]}" | grep -o 'X' | wc -l