#!/bin/bash

# PURPOSE: batch extraction or setting of skim notes data of PDF files using Skim's skimnotes command-line tool

# AUTHOR: Christiaan Hofman
# ASSUMPTIONS: skimnotes is located at /Applications/Skim.app/Contents/SharedSupport/skimnotes

# USAGE:
#  skimbulk get PDFDIR [SKIMDIR]
#	Extract skim notes from each skim-annotated pdf in specified folder and write them to SKIMDIR if supplied
#  skimbulk get PDFFILE [PDFDIR] [SKIMDIR]
#	Extract skim notes from PDFFILE and write them to a file by replacing PDFDIR by SKIMDIR if supplied
#  skimbulk set PDFDIR [SKIMDIR]
#	Writes skim notes data to each non-skim-annotated pdf in specified folder getting the .skim file from SKIMDIR if supplied
#  skimbulk set PDFFILE [PDFDIR] [SKIMDIR]
#	Writes skim notes data to PDFFILE getting the data from a .skim file by replacing PDFDIR by SKIMDIR if supplied
#  skimbulk test PDFDIR
#	Prints the name of all skim-annotated pdfs in specified folder 
#  skimbulk test PDFFILE
#	Prints the name of the pdffile when it has skim notes

skimnotes=/Applications/Skim.app/Contents/SharedSupport/skimnotes

if [[ $# -eq 1 && "$1" == version ]]; then
		
	echo "skimbulk version 1.1"
		
elif [[ $# -lt 2 || $# -gt 4 || ($# -eq 4 && ! -d "$3") || ! "$1" =~ get|set|test ]]; then
		
	echo "usage:"
	echo " skimbulk get|set|test PDFDIR [SKIMDIR]"
	echo "get or set Skim notes on PDF files in bulk, with PDF files in PDFDIR and skim files in SKIMDIR"
	echo "skimbulk, version 1.0"
	
elif [[ -d "$2" ]]; then
	
#	echo "after d test" # **
#	echo "$2" # **
	
	# recursively execute this script for all pdf files in the directory
#	echo "recursion" # **
#	echo "$2" # **
	find "$2" -type f -name "*.pdf" -exec "$0" "$1" "{}" "${@:2}" ";"
#	echo "after recursion" # **
	
elif ([[ "$1" == set && -f "$2" ]] && ! "$skimnotes" test "$2") || \
	 ([[ "$1" != set ]] && "$skimnotes" test "$2"); then
	
#	echo "after xattr test" # **
#	echo "$2" # **
	
	# reset the Internal Field Separator for word boundaries
	SAVEIFS=$IFS # default is {space, tab, and newline}
	IFS=$(echo -en "\n\b") # reset to {new line, backspace} to ignore space and tab in filenames
	
	pdfdir=$(dirname "$2") # path to file's directory
	pdfdir=$(cd "$pdfdir" && pwd) # expand and normalize path
	
	# if the pdf is not in a pdf bundle (pdfd)
	if [[ "$pdfdir" != *.pdfd ]]; then
		
#		echo "after pdfd test" # **
#		echo "$2" # **
		
		if [[ "$1" == test ]]; then
			
			echo "$2"
			
		else
			
			# replace extension for skim file
			skimfile="${2%.pdf}.skim"
			
			if [[ $# -gt 3 ]]; then
				
				# expand and normalize full path for pdf directory
				pdfroot=$(cd "$3" && pwd)
				
				# get associated directory for skim file
				skimdir="${pdfdir/#$pdfroot/$4}"
				
				skimfile="$skimdir/$(basename $skimfile)"
				
				# make sure file's directory exists for get
				[[ "$1" == get ]] && ([[ -d "$skimdir" ]] || mkdir -p "$skimdir")
				
			fi
			
			if [[ "$1" == get || -f "$skimfile" ]]; then
				
#				echo "after skim file test" # **
				echo "$2" # **
			
				# get or set skim notes
#				echo "skimnotes $1 $2 $skimfile" # **
				"$skimnotes" "$1" "$2" "$skimfile"
#				echo "after skimnotes" # **
				
			fi
			
		fi
		
	fi
	
	IFS=$SAVEIFS

fi