#!/usr/bin/env bash

# Horizontal search
TOTAL_XMAS=$( grep -o 'XMAS' input.txt | wc -l )
TOTAL_XMAS=$(( TOTAL_XMAS + $( grep -o 'SAMX' input.txt | wc -l ) ))

# Add spaces for cut use
sed -E 's/(.)/\1\ /g' input.txt > input-proc 
FIELD_COUNT=$( head -1 input-proc | awk '{print NF}' )
LINE_COUNT=$( cat input-proc | wc -l )
INPUT_PROC=$( cat input-proc )

# Transpose for vertical search
TOTAL_XMAS=$(( 
  TOTAL_XMAS + $(
    RSTRING=$( 
      for i in $( seq 1 $FIELD_COUNT )
      do
        printf "$INPUT_PROC" | cut -f $i -d " " | paste -s -d ''
      done 
    ) 
    echo $( printf "$RSTRING" | grep -o 'XMAS' | wc -l ) + $( printf "$RSTRING" | grep -o 'SAMX' | wc -l ) | bc
  )
))

# Diagonal forward search
for COL_START in $( seq 1 $FIELD_COUNT )
do
  COL_COUNTER=$COL_START
  TOTAL_XMAS=$((
    TOTAL_XMAS + $(
      RSTRING=$(
        while read -r LINE
        do
          if [[ $COL_COUNTER -gt $FIELD_COUNT || $COL_COUNTER < 1 ]] 
          then
          	continue
          fi
          printf "$LINE" | cut -f $COL_COUNTER -d " "
          (( COL_COUNTER++ ))
        done <<< "$INPUT_PROC" | paste -s -d ""
      )
      echo $( printf "$RSTRING" | grep -o 'XMAS' | wc -l ) + $( printf "$RSTRING" | grep -o 'SAMX' | wc -l ) | bc
    )
  ))
done
for ROW_START in $( seq 2 $LINE_COUNT )
do
  COL_COUNTER=1
  TOTAL_XMAS=$((
    TOTAL_XMAS + $(
      RSTRING=$(
        while read -r LINE
        do
          if [[ $COL_COUNTER -gt $FIELD_COUNT || $COL_COUNTER < 1 ]] 
          then
          	continue
          fi
          printf "$LINE" | cut -f $COL_COUNTER -d " "
          (( COL_COUNTER++ ))
        done <<< "$( tail -n +$ROW_START input-proc )" | paste -s -d ""
      )
      echo $( printf "$RSTRING" | grep -o  'XMAS' | wc -l ) + $( printf "$RSTRING" | grep -o  'SAMX' | wc -l ) | bc
    )
  ))
done
# Diagonal backwards search
for COL_START in $( seq $FIELD_COUNT -1 1 )
do
  COL_COUNTER=$COL_START
  TOTAL_XMAS=$((
    TOTAL_XMAS + $(
      RSTRING=$(
        while read -r LINE
        do
          if [[ $COL_COUNTER -gt $FIELD_COUNT || $COL_COUNTER < 1 ]] 
          then
          	continue
          fi
          printf "$LINE" | cut -f $COL_COUNTER -d " "
          (( COL_COUNTER-- ))
        done <<< "$INPUT_PROC" | paste -s -d "" 
      )
      echo $( printf "$RSTRING" | grep -o  'XMAS' | wc -l ) + $( printf "$RSTRING" | grep -o  'SAMX' | wc -l ) | bc
    )
  ))
done
for ROW_START in $( seq 2 $LINE_COUNT )
do
  COL_COUNTER=$FIELD_COUNT
  TOTAL_XMAS=$((
    TOTAL_XMAS + $(
      RSTRING=$(
        while read -r LINE
        do
          if [[ $COL_COUNTER -gt $FIELD_COUNT || $COL_COUNTER < 1 ]] 
          then
          	continue
          fi
          printf "$LINE" | cut -f $COL_COUNTER -d " "
          (( COL_COUNTER-- ))
        done <<< "$( tail -n +$ROW_START input-proc )" | paste -s -d ""
      ) 
      echo $( printf "$RSTRING" | grep -o  'XMAS' | wc -l ) + $( printf "$RSTRING" | grep -o  'SAMX' | wc -l ) | bc
    )
  ))
done

printf "%s\n" "$TOTAL_XMAS"