#! /bin/bash 
#title           :jpgHasDate.sh
#description     :Determine if an JPEG file has a date
#author		 :gmj@pobox.com
#date            :Sat Dec 19 15:35:06 2015
#version         :0.1
#usage		 :jpgHasDate.sh [optinos] FILE [FILE...]
#notes           :Experimeting with well-writtne bash
#bash_version    :
#==============================================================================

set -u   # exit on undefined
set -e   # exit on error
# set -x # echo during execution

# Useful tips
# http://www.kfirlavi.com/blog/2012/11/14/defensive-bash-programming/
readonly PROGNAME=$(basename $0)
readonly PROGDIR=$(readlink -m $(dirname $0))
readonly ARGS="$@"

usage() {
    if [ $# -gt 0 ]; then echo  "${PROGNAME}: $@"; echo; fi
    cat <<- EOF
usage: $PROGNAME [options] FILE [FILE...]
    
This program determins if a JPEG file has an Original Date stored
with it and prints the filename and/or date.

OPTIONS:
   -w --withdates	Select files with dates
   -m --missingdates	Select files with no dates
   -p --path		Print path of matching files
   -t --dates		Print dates of matching files
   -v --verbose         Verbose. You can specify more then one -v to have more verbose
   -d --debug           debug
   -h --help            show this help
    
Examples:
   print info about a single file
   $PROGNAME --test all

EOF
}


parseArgs() {
    # Option parsing courtesy of 
    # http://stackoverflow.com/questions/402377/using-getopts-in-bash-shell-script-to-get-long-and-short-command-line-options


    # NOTE: This requires GNU getopt.  On Mac OS X and FreeBSD, you have to install this
    # separately; see below.
    TEMP=`getopt -o wmptvdh --long withdates,missingdates,path,dates,verbose,debug,help \
            	  -n 'jpghasDate' -- "$@"`

    if [ $? != 0 ] ; then echo "getopt failed. Terminating..." >&2 ; exit 1 ; fi

    # Note the quotes around `$TEMP': they are essential!
    eval set -- "$TEMP"


    # Set default values

    # Selection Parameters
    OPT_SELECT_WITH_DATES=false		# print files that have dates
    OPT_SELECT_MISSING_DATES=false	# print files with no date
    # Output Parameters
    OPT_VERBOSE=false			# verbose output
    OPT_DEBUG=false			# debugging output
    OPT_PRINT_PATH=false  		# print path
    OPT_PRINT_DATES=false		# print date
    OPT_PRINT_ALL=true			# print all (default)

    while true; do
	case "$1" in
	    -w | --withdates ) OPT_SELECT_WITH_DATES=true; shift ;;
	    -m | --missingdates ) OPT_SELECT_MISSING_DATES=true; shift ;;
	    -p | --path ) OPT_PRINT_PATH=true; shift ;;
	    -t | --dates ) OPT_PRINT_DATES=true; shift ;;
	    -v | --verbose ) OPT_VERBOSE=true; shift ;;
	    -d | --debug ) OPT_DEBUG=true; shift ;;
	    -h | --help ) usage; exit 0;shift ;;        
	    -- ) shift; break ;;
	    * ) break ;;
	esac
    done
    
    if [ $# -lt 1 ] ; then usage "Missing argument.  Need at least one filename."; exit 1; fi

    # Defualt to printing all
    if ! ( $OPT_PRINT_PATH || $OPT_PRINT_DATES ); then 
	OPT_PRINT_PATH=true
	OPT_PRINT_DATES=true
    fi
    
    # Defualt to selectiing all
    if ! ( $OPT_SELECT_WITH_DATES || $OPT_SELECT_MISSING_DATES ); then 
	OPT_SELECT_WITH_DATES=true
	OPT_SELECT_MISSING_DATES=true
    fi

    # Make parsing paramters readonly

    readonly OPT_SELECT_WITH_DATES=${OPT_SELECT_WITH_DATES}	# print files that have dates
    readonly OPT_SELECT_MISSING_DATES=${OPT_SELECT_MISSING_DATES}	# print files with no date
    readonly OPT_VERBOSE=${OPT_VERBOSE}				# verbose output
    readonly OPT_DEBUG=${OPT_DEBUG}				# debugging output
    readonly OPT_PRINT_PATH=${OPT_PRINT_PATH}			# print path
    readonly OPT_PRINT_DATES=${OPT_PRINT_DATES}			# print date
    readonly OPT_PRINT_ALL=${OPT_PRINT_ALL}			# print all (default)

    readonly OPT_ARGS="$@"
}

printSelectedFiles () {
    for file in "$*"; do
	if $OPT_DEBUG; then echo file $file >&2; fi
	date=$(exiftool $file | grep Orig || echo "NONE")
	date=$(echo $date | sed -e 's/Date\/Time Original\s*\:\s*//')
	output=""

	if $OPT_PRINT_PATH; then output="$file"; fi

	if $OPT_PRINT_DATES; then output="$output : $date"; fi
	
	if $OPT_SELECT_MISSING_DATES; then 
	    if [[ $date == *"NONE"* ]]; then
		echo $output
	    fi
	fi

	if $OPT_SELECT_WITH_DATES; then 
	    if [[ $date != *"NONE"* ]]; then
		echo $output
	    fi
	fi    
    done
}

main() {
    parseArgs $ARGS
    printSelectedFiles $OPT_ARGS
}

main