#!/usr/local/bin/perl



my $NEXT_DAY_HH_THRESHOLD = "08";		#For example, if set to 08, This means that any picture taken before 08AM will be considered part of the previous day -- assuming there were pics that previous day and this is a running set



use strict;

my $DEBUG=0;							#set to 2 to actually see hash tables
my $filenameprefix="";
my $filename="";
my $info="";
my $tmpdateinfo="";
my $filenameprefix="";
my $SKIP="";
my $original_filename="";
my $scrubbed_date="";
my $YYYYMMDD="";
my $HH="";
my $MM="";
my $SS="";
my %YYYYMMDD_USED=();
my $newyyyymmdd="";
my $temp="";

use Image::ExifTool 'ImageInfo';
#use Clint::Date;									#functions have now been copied into this script so as to not rely on a Clint library

while ($filename=<>) {
    chomp $filename;
	$SKIP=1;
    if ($filename =~ /\.jpg$/i)  { $SKIP=0; }
    if ($filename =~ /\.raw$/i)  { $SKIP=0; }		#no clue if RAW files have EXIF or not
    if ($filename =~ /\.wav$/i)  { $SKIP=0; }		#wikipedia says WAV  can have exif
    if ($filename =~ /\.tiff$/i) { $SKIP=0; }		#wikipedia says TIFF can have exif
	if ($SKIP) { next; }
	$original_filename=$filename;

	if ($DEBUG) { print "filename is $filename\n"; }

	$info = &ImageInfo($filename);											
	if ($DEBUG>1) { foreach my $key (sort keys %$info) { print "key=$key, data=$info->$key\n"; } }

	$tmpdateinfo = $info->{DateTimeOriginal};								
	if ($DEBUG>0) { print "tmpdateinfo for $filename is \"$tmpdateinfo\"\n"; }

	$tmpdateinfo =~ /^([0-9]{4}):([01][0-9]):([0-3][0-9]) ([0-2][0-9]):([0-5][0-9]):([0-5][0-9])/;					#2009:01:24 23:58:15
	if ($DEBUG>0) { print "for $filename, \$1=$1,\$2=$2,\$3=$3,\$4=$4,\$5=$5,\$6=$6\n"; }
	$YYYYMMDD = $1 . $2 . $3;		#YYYYMMDD --- the date
	$HH=$4;  $MM=$5;  $SS=$6;		#HHMMSS ----- the time
	$YYYYMMDD_USED{$YYYYMMDD}="1";											#store the date, so if we go past midnight we can "remember" there were pictures before midnight
	$filenameprefix = $YYYYMMDD;

	if (($HH >= 00) && ($HH < $NEXT_DAY_HH_THRESHOLD)) {					#if it's between midnight and our next-day-threshold (ex: 8AM)
		if ($DEBUG) { print "** The \$HH of $HH for $filename falls between 00 and $NEXT_DAY_HH_THRESHOLD!\n"; }
		$newyyyymmdd=&decrement_date_by_one_day($YYYYMMDD);					#then we need to figure out what the previous day is in YYYYMMDD format
		if ($DEBUG) { print "** So we decreament $YYYYMMDD one day to get $newyyyymmdd and check if there were pictures\n"; }
		if ($YYYYMMDD_USED{$newyyyymmdd} eq "1") {							#and if we "remember" there being pictures on that date
			$filenameprefix = $newyyyymmdd;									#then this is a continuance of that event, and we should use that date instead
		}
	}

	if ($filenameprefix ne "") { $filenameprefix .= " - "; }				
	if ($DEBUG>0) { print "fileprefix for $filename is $filenameprefix\n"; }

	##### BONUS FUNCTIONALITY; CLEAN UP THE NAME A BIT:
	$filename =~ s/_IMG.JPG/.jpg/i;									

	print qq[mv "$original_filename" "$filenameprefix$filename"\n];
}









#################################################################################################################################
sub decrement_date_by_one_day {		#USAGE: ($newyymmdd)=&decrement_date_by_one_day($yymmdd);
	#USES last_day_of_month;
	my $date = $_[0];
	my $year="";
	my $month="";
	my $day="";
	my $MONTH_DECREMENTED=0;

	#DEBUG: print "\n\ndate=$date,length(\$date) is ";print length($date);print "\n\n";

	#FIRST let us define all the numbers and strings we will need:
	if (length($date) == 8) {
		$year = $day = $month = $date;
		$year      =~ s/(....)..../$1/;
		$month     =~ s/....(..)../$1/;
		$day       =~ s/......(..)/$1/;
	} else {
		$year = $day = $month = $date;
		$year      =~ s/(..)..../$1/;
		$month     =~ s/..(..)../$1/;
		$day       =~ s/....(..)/$1/;
	}

	$day--;                         #decrement day

	if (!$day) {                    #if day is zero, decrement month, set flag
			$month--;
			$MONTH_DECREMENTED=1;
	}#endif

	if (!$month) {                  #if month is zero, it's really december of the last year
			$year--;
			$month=12;
	}#endif

	if ($year == -1) { $year=99; }  #if year is -1, it's really <century>99

	if ($MONTH_DECREMENTED) {       #if month was decremented, set day to last day of month
			$day=&last_day_of_month($month,$year);
	}#endif
	if ($day   =~ /^[1-9]$/) { $day   = "0$day";   }        #normalize values to have 0 in front of them if less than 10
	if ($month =~ /^[1-9]$/) { $month = "0$month"; }
	if ($year  =~ /^[1-9]$/) { $year  = "0$year";  }

	return "$year$month$day";

}#endsub decrement_date_by_one_day
#################################################################################################################################


#########################################################################################################################
sub last_day_of_month {		#USAGE: ($day)=&last_day_of_month(2,1998);
	my ($month)=$_[0];
	my ($year)=$_[1];
	my $day="";

	#### months with 31 days:
	if (($month==1) || ($month==3) || ($month==5) || ($month==7)
	 || ($month==8) || ($month==10) || ($month==12)) {
			$day=31;
	#### months with 30 days:
	} elsif (($month==4) || ($month==6) || ($month==9) || ($month==11)) {
			$day=30;
	### february is special:
	} elsif ($month==2) {
			if (($year % 4)==0) {
					$day=29;
			} else {
					$day=28;
			}#endif it's a leap year
	} else {
			$temp  = "\n\n******* INTERNAL ERROR MONTH_1_X: month=$month,year=$year *******\n";
			$temp .= "        (THIS SHOULD NEVER HAPPEN)\n\n";
			print $temp;
	}#endif

	#print "<h1>Last day of month \"$month\" in year \"$year\" is \"$day\"</h1>\n\n";	#
	 
	return($day);
}#endsub last_day_of_month
#########################################################################################################################