#!/bin/bash
#######################################################
# Script to perform a geometry optimistion using psi4 #
#######################################################

set -e

#########################
# Test usage is correct #
#########################

if [ $# -ne 2 ]; then
         echo 1>&2 "Usage: psi4_relax <exe> <seed>"
         exit 127
fi

###########################
# Set the input variables #
###########################

exe=$1
seed=$2

root=${seed%%-*}
root=${root##*\/}

############
# Run psi4 #
############


# Build the psi4 input file

cabal cell psi4 < $seed.cell > $seed.psin  

echo "set {" >> $seed.psin
#echo "reference uks" >> $seed.psin
#echo "frac_start 1" >> $seed.psin
echo "basis cc-pvdz" >> $seed.psin
echo "scf_type df" >> $seed.psin
echo "guess sad" >> $seed.psin
echo "}" >> $seed.psin
echo "optimize('pbe')" >> $seed.psin

# Run psi4

set +e
$exe $seed.psin $seed.psout 2>/dev/null
set -e

# Check for failure

if `grep -q coffee $seed.psout` ; then
    exit 0 # Fail peacefully
fi

# Construct a fake Castep output file

echo " *  Pressure: 0.0" >  $seed.castep
grep "Final energy is" $seed.psout | tail -1 | awk '{print " PSI4: Final Enthalpy     = "$4}' >> $seed.castep
echo "Current cell volume = 0.00000001" >> $seed.castep

# Save the final structure in Castep -out.cell format

if [[ -e $seed.psout ]]; then
    cabal psi4 cell < $seed.psout > $seed-out.cell
fi

# Return the key results

grep " *  Pressure: " $seed.castep | awk '{printf "%-20s%10.8f\n", "Pressure: ",$3}'
grep " PSI4: Final Enthalpy     = " $seed.castep | awk '{printf "%-20s%10.8f\n", "Enthalpy: ",$5}'
grep "Current cell volume = " $seed.castep | awk '{printf "%-20s%10.8f\n", "Volume: ",$5}'

exit 0