#! /bin/bash
# Last edited on 2010-03-04 14:58:47 by stolfi

usage="$0 [ -tag TAG ] main.{gif|png} main.pov [ FILES... ]"

# This script is executed by students in order to hand labwork in.
# Copies the named files from the current directory to the user's
# directory "public_html/mo814/YYYY-MM-DD/", creating it if necessary. Also
# sets the proper file and directory permissions. 
# If "-tag" is given, the destination directory will be
# "public_html/mo814/YYYY-MM-DD-TAG/". 

# Must be executed in a Linux environment.

if [[ $# -lt 2 ]]; then
  echo "$0: bad arguments"  1>&2
  echo "usage: ${usage}" 1>&2; exit 1
fi

tag=""
while [[ ( $# -gt 0 ) && ( "/$1" =~ /-.* ) ]]; do 
  if [[ ( $# -ge 2 ) && ( "/$1" == "/-tag" ) ]]; then
    tag="-$2"; shift; shift;
  else
    echo 'invalid option "'"$1"'"' 1>&2; 
    echo "usage: ${usage}" 1>&2; exit 1
  fi
done

image="$1"; shift
source="$1"; shift
extras=( $* )

# Make sure the files have the right extension:

if [[ ( "@${image}" != "@main.png" ) && ( "@${image}" != "@main.gif" ) ]]; then
  echo "${image}"' should be "main.png" or "main.gif"' 1>&2; exit 1
fi
if [[ "@${source##*.}" != "@pov" ]]; then
  echo "${source}"' should be "main.pov"' 1>&2; exit 1
fi

dt=`/bin/date '+%Y-%m-%d'`
pubdir="${HOME}/public_html/mc930/${dt}${tag}"

# Make sure the target directory exists:
mkdir -p ${pubdir}

# Make sure the target directory is writable by user:
chmod u+w ${pubdir}

# Make sure that the target directory is readable through HTTP:
tmp="${pubdir}"
while [[ "@${tmp}" != "@${HOME}" ]]; do 
  # echo "tmp = ${tmp}"
  chmod a+rX ${tmp}
  tmp="${tmp%/*}"
done
chmod -v a+X ${HOME}

# Check whether we succeeded:
if [[ ! ( -d ${pubdir} ) ]]; then
  echo "failed to create directory ${pubdir}" 1>&2; exit 1
fi
if [[ ! ( -w ${pubdir} ) ]]; then
  echo "directory ${pubdir} is not writable" 1>&2; exit 1
fi

# Remove any previously exported version of the exported files:
( cd ${pubdir} && \
  /bin/rm -fv main.png main.gif main.pov ${image} ${source} ${extras} \
) 

# Make sure the files exist and have nonzero length,
# then copy them to the target directory and make sure that
# they are accessible through HTTP:
for f in ${image} ${source} ${extras[@]}; do
  if [[ ! ( -r ${f} ) ]]; then 
    echo "I cannot find ${f} in the current directory" 1>&2; exit 1
  fi
  if [[ -z ${f} ]]; then
    echo "File ${f} has zero length"; exit 1
  fi
  dest="${pubdir}/${f}"
  cp -avi ${f} ${dest}
  chmod og=r,u=rw ${dest}
done