Appease the margin police at all costs

check_margins.sh

#!/usr/bin/env bash

####
# Original version of this file was created by Dr. Chuck Cartledge
# as a make file and can be found in his WS-DL blog post:
# https://ws-dl.blogspot.com/2014/07/2014-0-7-2-ode-to-margin-police-or-how.html
####

#### Set these variables to match your setup
CHECK="msThesis"
CHECKEXT="pdf"
MARGINDIR="Margins"
LATEX="pdflatex"

#### Values used to determine if a page violates margin police rules
goodSum=484704
threshold=10

#### Vars and functions used interally
checkWhat="${CHECK}.${CHECKEXT}"
resultsFile="marginResults.txt"
workDir=$(pwd)

#### The Magic
function checkMargins () {
  cp ${checkWhat} ${MARGINDIR}
  cd ${MARGINDIR}
  pdftk ${checkWhat} burst
  convert -size 35x17 xc:skyblue insertPage.png
  convert -size 432x648 xc:skyblue insertBody.png
  toProcess=$(ls pg_*.pdf)
  echo "Processing ${#toProcess} pages"
  for pgpdf in ${toProcess}; do
    composite -geometry +108+72 insertBody.png ${pgpdf} temp.png
    composite -geometry +508+36 insertPage.png temp.png tempAlso.png
    convert tempAlso.png -flatten ${pgpdf/.pdf/.redacted.pdf}
    echo "Processed ${pgpdf}"
  done
  pdftk *redacted.pdf cat output ${checkWhat/.pdf/.redacted.pdf}
  toProcess=$(ls pg_*.redacted.pdf)
  echo "Checking margins for ${#toProcess} pages"
  for redacted in ${toProcess}; do
    echo "Checking ${redacted} for margins violation"
    convert ${redacted} -format %c histogram:info: > hist.txt
    skyblue=$(grep SkyBlue hist.txt | cut -d:  -f1 | tr -d "\n")
    white=$(grep white hist.txt | cut -d:  -f1 | tr -d "\n")
    dif=$(expr ${goodSum} - ${skyblue} - ${white})
    if [[ ${dif} -ge ${threshold} ]]; then
      echo "${redacted} is bad"
      echo "${redacted} is bad" >> ${resultsFile}
      cat hist.txt >> ${resultsFile}
    else
      rm ${redacted} ${redacted/.redacted.pdf/.pdf}
    fi
  done
  rm hist.txt doc_data.txt insertBody.png insertPage.png temp.png tempAlso.png
  if [[ -f ${resultsFile} ]]; then
    echo "Looks like there is still some work to be done in order to appease the margin police"
    echo "Offending pages and results per page are found in the directory ${MARGINDIR}"
    echo "Best of luck. Goodby and have nice day"
  else
    echo "No offending pages were found"
    echo "Goodby and have nice day"
  fi
}

if [[ ! -d ${MARGINDIR} ]]; then
  mkdir ${MARGINDIR}
else
  hasStuff=$(ls ${MARGINDIR})
  if [[ ${#hasStuff} -gt 0 ]]; then
    rm ${MARGINDIR}/*
  fi
fi

if [[ ! -f ${checkWhat} ]]; then
  echo "The pdf to be checked, ${checkWhat}, does not exist"
  echo "Goodby and have nice day"
  exit 1
fi

hasPDFTK=$(hash pdftk 2>/dev/null)
if [[ ! hasPDFTK ]]; then
  echo "The program pdftk is not installed"
  echo "Please install it via [sudo] apt install pdftk"
  echo "Goodby and have nice day"
  exit 1
fi

hasImageMagick=$(hash convert 2>/dev/null)
if [[ ! hasImageMagick ]]; then
  echo "The program ImageMagick is not installed"
  echo "Please install it via [sudo] apt install imagemagick"
  echo "Goodby and have nice day"
  exit 1
fi

checkMargins