#!/bin/sh

# run from directory where this script is
cd `echo $0 | sed 's/\(.*\)\/.*/\1/'` # extract pathname
EXAMPLE_DIR=`pwd`

# check whether echo has the -e option
if test "`echo -e`" = "-e" ; then ECHO=echo ; else ECHO="echo -e" ; fi

$ECHO
$ECHO "$EXAMPLE_DIR : starting"
$ECHO
$ECHO "This example will calculate the initial state contribution for a Rh011 slab"

# set the needed environment variables
. ../../../environment_variables

# required executables and pseudopotentials
BIN_LIST="pw.x initial_state.x"
PSEUDO_LIST="Rh.pbe-rrkjus_lb.UPF Rhs.pbe-rrkjus_lb.UPF"

$ECHO
$ECHO "  executables directory: $BIN_DIR"
$ECHO "  pseudo directory:      $PSEUDO_DIR"
$ECHO "  temporary directory:   $TMP_DIR"
$ECHO
$ECHO "  checking that needed directories and files exist...\c"

# check for directories
for DIR in "$BIN_DIR" "$PSEUDO_DIR" ; do
    if test ! -d $DIR ; then
        $ECHO
        $ECHO "ERROR: $DIR not existent or not a directory"
        $ECHO "Aborting"
        exit 1
    fi
done
for DIR in "$TMP_DIR" "$EXAMPLE_DIR/results" ; do
    if test ! -d $DIR ; then
        mkdir $DIR
    fi
done
cd $EXAMPLE_DIR/results

# check for executables
for FILE in $BIN_LIST ; do
    if test ! -x $BIN_DIR/$FILE ; then
        $ECHO
        $ECHO "ERROR: $BIN_DIR/$FILE not existent or not executable"
        $ECHO "Aborting"
        exit 1
    fi
done

# check for pseudopotentials
for FILE in $PSEUDO_LIST ; do
    if test ! -r $PSEUDO_DIR/$FILE ; then
       $ECHO
       $ECHO "Downloading $FILE to $PSEUDO_DIR...\c"
            $WGET $PSEUDO_DIR/$FILE $NETWORK_PSEUDO/$FILE 2> /dev/null
    fi
    if test $? != 0; then
        $ECHO
        $ECHO "ERROR: $PSEUDO_DIR/$FILE not existent or not readable"
        $ECHO "Aborting"
        exit 1
    fi
done
$ECHO " done"

# how to run executables
PW_COMMAND="$PARA_PREFIX $BIN_DIR/pw.x $PARA_POSTFIX"
IS_COMMAND="$PARA_PREFIX $BIN_DIR/initial_state.x $PARA_POSTFIX"
$ECHO
$ECHO "  running pw.x as: $PW_COMMAND"
$ECHO "  running initial_state.x as: $IS_COMMAND"
$ECHO

#
# self-consistent calculation. Note the definitions in ATOMIC_SPECIES and ntyp in &system
# 
cat > rh011slab.scf.in << EOF
 &control
    calculation='scf',
    restart_mode='from_scratch',
    prefix='Rh011',
    pseudo_dir = '$PSEUDO_DIR',
    outdir='$TMP_DIR'
 /
&system
    nat=5, ntyp=2,
    ibrav=0, celldm(1)=10.31510000,
    ecutwfc = 25, occupations='smearing', degauss = 0.02, smearing='mv',
/
&electrons
    mixing_beta = 0.3
    conv_thr =  1.0d-6
/
CELL_PARAMETERS alat
0.50000000 0.00000000 0.00000000
0.00000000 0.70710678 0.00000000
0.00000000 0.00000000 3.00000000

ATOMIC_SPECIES
Rh    1.0   Rh.pbe-rrkjus_lb.UPF 
Rhs   1.0   Rhs.pbe-rrkjus_lb.UPF

ATOMIC_POSITIONS (alat)

Rh     0.25000000     0.35000000     0.50000000
Rh     0.00000000     0.00000000     0.25000000
Rh     0.25000000     0.35000000     0.00000000
Rh     0.00000000     0.00000000    -0.25000000
Rh     0.25000000     0.35000000    -0.50000000

K_POINTS {gamma}
EOF
$ECHO
$ECHO "  running pw.x for Rh011 slab...\c"
$PW_COMMAND < rh011slab.scf.in > rh011slab.scf.out
check_failure $?
$ECHO " done"

# Initial state calculation as a post-processing tool
# 
cat > rh011slab.istate.in << EOF
&inputpp
       prefix='Rh011',
       outdir='$TMP_DIR'
       excite(1) = 2,
/
EOF
$ECHO
$ECHO "  running initial_state.x for RhUS->RhsUS ...\c"
$IS_COMMAND < rh011slab.istate.in > rh011slab.istate.out
check_failure $?
$ECHO " done"

#
#       Extract data and write results
#
enbulk=$(grep "atom   3 type  1" rh011slab.istate.out | head -n1 | cut -d" " -f 19)
enlay1=$(grep "atom   2 type  1" rh011slab.istate.out | head -n1 | cut -d" " -f 19)
ensurf=$(grep "atom   1 type  1" rh011slab.istate.out | head -n1 | cut -d" " -f 19)


clssurfry=$(echo "scale=5; ($enbulk)-($ensurf)" | bc) 
clssurfev=$(echo "scale=5; (($enbulk)-($ensurf))*13.6" | bc) 

clslay1ry=$(echo "scale=5; ($enbulk)-($enlay1)" | bc) 
clslay1ev=$(echo "scale=5; (($enbulk)-($enlay1))*13.6" | bc) 

$ECHO "" > initial-state.txt
$ECHO "IS contribution for the bulk atom: $enbulk (Ry)" >> initial-state.txt
$ECHO "IS contribution for the surface atom: $ensurf (Ry)" >> initial-state.txt
$ECHO "IS contribution for the layer(-1) atom: $enlay1 (Ry)" >> initial-state.txt
$ECHO "" >> initial-state.txt
$ECHO "------------------------------------------" >> initial-state.txt
$ECHO "" >> initial-state.txt
$ECHO "IS shift surface: $clssurfev (eV)" >> initial-state.txt
$ECHO "IS shift layer(-1): $clslay1ev (eV)" >> initial-state.txt

$ECHO
$ECHO "  Results written in results/initial-state.txt !"
$ECHO
$ECHO "  cleaning $TMP_DIR...\c"
rm -rf $TMP_DIR/Rh011.*

$ECHO
$ECHO "$EXAMPLE_DIR: done"

