#! /bin/sh

# foreachpam - execute a program for each image of a PAM image stream

# Copyright (c) 2006-2022 Erik Auerswald <auerswal@unix-ag.uni-kl.de>
# 
# Permission is hereby granted, free of charge, to any person obtaining a
# copy of this software and associated documentation files (the "Software"),
# to deal in the Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
# and/or sell copies of the Software, and to permit persons to whom the
# Software is furnished to do so, subject to the following conditions:
# 
# The above copyright notice and this permission notice shall be included
# in all copies or substantial portions of the Software.
# 
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
# ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.

[ $# -gt 0 ] || { echo "foreachpam: usage: foreachpam PROG [PROGARGS]" 1>&2; \
                  exit 1; }

which pamsplit > /dev/null 2>&1 || \
    { echo "foreachpam: error: pamsplit not in PATH" 1>&2; exit 1; }

which "$1" > /dev/null 2>&1 || \
    { echo "foreachpam: error: $1 not in PATH" 1>&2; exit 1; }

dir="`mktemp -dt`" || \
    { echo "foreachpam: error: could not create temporary directory" 1>&2; \
      exit 1; }

trap "rm -rf \"${dir}\"" 0

pamsplit - "${dir}/image%d.pnm" -padname=5 -quiet

for image in "${dir}"/image?????.pnm; do
    "$@" < "$image"
done