#!/bin/bash
#
# This script tangles all the org-mode files in the src directory of QMCkl.
# It needs to be run from in the src directory.  It uses the config_tangle.el
# Emacs configuration file, which contains information required to compute the
# current file names using for example ~(eval c)~ to get the name of the
# produced C file. The org-mode file is not tangled if the last modification
# date of the org file is older than one of the tangled files.
# The =missing= script is used to check if emacs is present on the system.

if [[ -z ${srcdir} ]] ; then
  echo "Error: srcdir environment variable is not defined"
  exit 1
fi

if [[ -z ${top_builddir} ]] ; then
   echo "Error: top_builddir environment variable is not defined"
   exit 1
fi

function tangle()
{
    local org_file=$1
    local c_file=${org_file%.org}.c
    local f_file=${org_file%.org}.f90

    if [[ ${org_file} -ot ${c_file} ]] ; then
        return
    elif [[ ${org_file} -ot ${f_file} ]] ; then
        return
    fi
    ${srcdir}/tools/missing \
        emacs --batch ${org_file} \
         --load=${srcdir}/tools/config_tangle.el \
        -f org-babel-tangle
}

for i in $@
do
    tangled=${i%.org}.tangled
    tangled=${top_builddir}/src/$(basename $tangled)
    NOW=$(date +"%m%d%H%M.%S")
    tangle ${i} &> $tangled 
    rc=$?
    # Make log file older than the tangled files
    touch -t ${NOW} $tangled
    # Fail if tangling failed
    if [[ $rc -ne 0 ]] ; then
       cat $tangled
       exit $rc
    fi
done