#!/bin/sh
#
# copy-camera-media - copy images and videos off Bien's Olympus and HTC
#
# $Id$

# written to be called automatically when a camera or phone is plugged in,
# but it can also copy files from directories supplied as arguments

PATH=/usr/local/bin:/usr/bin:/bin
export PATH

Die()
{
  echo $0: fatal error: $@ 1>&2
  exit 1
}

DieIfMissing()
{
  for x in "$@"
  do
    type "$x" >/dev/null || Die missing executable $x
  done
}

DieIfMissing exiftool rsync

# parse the command line: command [-options] [sourcedir] [destdir]

rsyncopts=

while :
do
  case "$1" in
  -*|--*)
    rsyncopts="$rsyncopts $1"
    shift
    ;;
  *)
    break
    ;;
  esac
done

# default source directory
[ $# -eq 0 ] && set /media

[ -d "$1" ] || Die cannot find source directory $1

# default destination directory
if [ $# -eq 1 ]
then
  HOME=`getent passwd "$me" | awk -F: '{print $6}'`
  [ -d "$HOME" ] || Die cannot find home directory $HOME
  set "$1" $HOME/Pictures
fi

[ -d "$2" ] || Die cannot find destination directory $2

# we may be started automatically as root
# in which case we want to execute the real work
# as the user who actually owns the pictures
# convention: if $OWNER is set, it is the user in question;
# if not, we scan all picture owners and reexecute as them

me=`id -nu`

case "$OWNER" in
"$me") ;;
'')
  find "$@" -type f \
    -exec exiftool -if '!defined ${Error}' -p '${Directory}/${FileName}' '{}' + 2>/dev/null |
  perl -lne '$seen{$_}++ or print' |  # why is this necessary?
  perl -lne '
    my $o = (stat($_))[4] // next;
    my @u = getpwuid($o) or next;
    my $o = $u[0] or next;   # never run as unknown user or root
    $seen{$o}++ or print $o  # deduplicate
  ' |
  while read ownerid
  do
    owner=`getent passwd $ownerid | awk -F: '{print $1}'`
    case "$owner" in
    "$me") exec env OWNER=$owner PATH=$PATH "$0" $rsyncopts "$@";;
    *) exec sudo -u $owner env OWNER=$owner PATH=$PATH "$0" $rsyncopts "$@";;
    esac
  done
  exit $?
  ;;
*)
  if getent passwd "$OWNER" >/dev/null
  then
    sudo -u $OWNER env OWNER=$OWNER PATH=$PATH "$0" $rsyncopts "$@"
    exit $?
  else
    Die cannot execute as $OWNER
  fi
  ;;
esac

#echo executing as $me

find "$1" -type f -user "$me" \
  -exec exiftool -if '!defined ${Error}' -p '${Directory}/${FileName}' '{}' + 2>/dev/null |
while IFS= read -r f
do
  exiftool -q -d '%Y %m' -p '${filemodifydate} XXX ${model} XXX ${software}' "$f" 2>/dev/null |
  perl -wlpe '
    my ($date, $model, $software) = split(/ XXX /);
    warn "date: $date, camera model: $model, software: $software\n";
    $date =~ s# 0[1-6]#-helft1# or $date =~ s# [01]\d#-helft2#;
    if ($model eq "HTC Desire")
    # matches Bien"s HTC
    {
      $model = "HTC"
      # for backward compatibility only
    }
    elsif ($model eq "C765UZ")
    # matches Bien"s Olympus
    {
      $model = "Olympus"
      # for backward compatibility only
    }
    elsif ($model =~ /^VG\w+/)
    # matches the *.JPG on Reinier"s Olympus VG-150
    {
      $model = "Olympus $&"
    }
    elsif ($model =~ /^Unknown/ && $software =~ /^OLYMPUS (\w+)/)
    # matches the *.AVI on Reinier"s Olympus VG-150 (seriously!)
    {
      $model = "Olympus $1"
    }
    elsif (!$model && $software =~ /MediaTek/)
    # matches Reinier"s Acer X220
    # this heuristic should be smarter
    {
      $model = "Acer Z220"
    }
    elsif (!$model)
    {
     #warn "unspecified, unguessed camera model\n";
      $model = "unknown"
    }
    $model =~ s#\s+##g;

    $_ = sprintf("%s-%s", $date, $model);
    warn "semester: $date, adjusted camera model: $model, software: $software\n";
   #warn "dir: $_\n";
  ' |
  while read reltgtdir
  do
    M=${T}/$reltgtdir
    [ -d "$M" ] || mkdir "$M" || continue
    echo rsync -a $rsyncopts "$f" "$M/"
    rsync -a $rsyncopts "$f" "$M/"
  done
done