#!/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 shows how to use pw.x and projwfc.x to calculate"
$ECHO "the Magnetic Anisotropy Energy in Co using the Force Theorem"

# set the needed environment variables
. ../../../environment_variables
# required executables and pseudopotentials
BIN_LIST="pw.x projwfc.x"
PSEUDO_LIST="Co.pbe-nd-rrkjus.UPF  Co.rel-pbe-nd-rrkjus.UPF"

$ECHO
$ECHO "  executables directory: $BIN_DIR"
$ECHO "  pseudo directory:      $PSEUDO_DIR"
$ECHO "  temporary directory:   $TMP_DIR"
$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 $PARA_POSTFIX"
PROJ_COMMAND="$PARA_PREFIX $BIN_DIR/projwfc.x $PARA_POSTFIX"
$ECHO
$ECHO "  running pw.x as: $PW_COMMAND"
$ECHO

# self-consistent calculation for 3-layer Co slab, no SOC
cat > sr.in << EOF
 &control
    calculation = 'scf',
    restart_mode = 'from_scratch',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir = '$TMP_DIR/',
    prefix = 'sr'
 /
 &system
    ibrav = 4,
    celldm(1) = 4.723553684826,
    celldm(3) = 10.0,
    nat= 3,
    ntyp= 1,
    nspin = 2,
    ecutwfc = 25.0,
    ecutrho = 200.0,
    occupations='smearing',
    smearing='mv',
    degauss=0.005
    starting_magnetization(1)=1.0,
 /
 &electrons
    conv_thr = 1.0e-10
    mixing_mode = 'local-TF'
    mixing_beta = 0.7
 /
 &ions
 /
ATOMIC_SPECIES
Co 58.933  Co.pbe-nd-rrkjus.UPF
ATOMIC_POSITIONS {angstrom}
Co       1.249798200   0.721571500   0.000000000
Co       0.000000000   0.000000000   2.019286000
Co       1.249798200   0.721571500   4.038572000
K_POINTS (automatic)
12 12 1 1 1 0
EOF

$ECHO "  running SR calculation ...\c"
$PW_COMMAND < sr.in > sr.out
check_failure $?
$ECHO " done"

$ECHO "  create SOC folders and copy there SR density and spin moment...\c"
mkdir -p $TMP_DIR/par.save
mkdir -p $TMP_DIR/per.save
cp $TMP_DIR/sr.save/data-file*.xml $TMP_DIR/par.save/
cp $TMP_DIR/sr.save/charge-density.dat $TMP_DIR/par.save/
cp $TMP_DIR/sr.save/data-file*.xml $TMP_DIR/per.save/
cp $TMP_DIR/sr.save/charge-density.dat $TMP_DIR/per.save/
$ECHO " done"


# NSCF run with SOC for parallel configuration 
cat > par.in << EOF
 &control
    calculation='nscf'
    restart_mode='from_scratch',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir = '$TMP_DIR/',
    prefix='par'
    verbosity = 'high'
 /
 &system
    ibrav = 4,
    celldm(1) = 4.723553684826,
    celldm(3) = 10.0,
    nat= 3,
    ntyp= 1,
    ecutwfc = 25.0,
    ecutrho = 200.0,
    occupations='smearing',
    smearing='mv',
    degauss=0.005
    starting_magnetization(1)=1.0,
    noncolin = .true.
    lspinorb = .true.
    angle1(1) = 90, 
    angle2(1) = 0,
    lforcet = .true.
    nosym = .true.
 /
 &electrons
    startingpot = 'file'
    diago_thr_init = 1.d-14
    mixing_mode = 'local-TF'
    mixing_beta = 0.7
 /
 &ions
 /
ATOMIC_SPECIES
Co 58.933  Co.rel-pbe-nd-rrkjus.UPF
ATOMIC_POSITIONS {angstrom}
Co       1.249798200   0.721571500   0.000000000
Co       0.000000000   0.000000000   2.019286000
Co       1.249798200   0.721571500   4.038572000
K_POINTS (automatic)
4 4 1 1 1 0
EOF
$ECHO "  NSCF run with SOC for parallel configuration ...\c"
$PW_COMMAND < par.in > par.out
check_failure $?
$ECHO " done"

# NSCF run with SOC for perpendicular configuration 
cat > per.in << EOF
 &control
    calculation='nscf'
    restart_mode='from_scratch',
    pseudo_dir = '$PSEUDO_DIR/',
    outdir = '$TMP_DIR/',
    prefix='per'
    verbosity = 'high'
 /
 &system
    ibrav = 4,
    celldm(1) = 4.723553684826,
    celldm(3) = 10.0,
    nat= 3,
    ntyp= 1,
    ecutwfc = 25.0,
    ecutrho = 200.0,
    occupations='smearing',
    smearing='mv',
    degauss=0.005
    starting_magnetization(1)=1.0,
    noncolin = .true.
    lspinorb = .true.
    angle1(1) = 0, 
    angle2(1) = 0,
    lforcet = .true.
    nosym = .true.
 /
 &electrons
    startingpot = 'file'
    diago_thr_init = 1.d-14
    mixing_mode = 'local-TF'
    mixing_beta = 0.7
 /
 &ions
 /
ATOMIC_SPECIES
Co 58.933  Co.rel-pbe-nd-rrkjus.UPF
ATOMIC_POSITIONS {angstrom}
Co       1.249798200   0.721571500   0.000000000
Co       0.000000000   0.000000000   2.019286000
Co       1.249798200   0.721571500   4.038572000
K_POINTS (automatic)
4 4 1 1 1 0
EOF
$ECHO "  NSCF run with SOC for perpendicular configuration ...\c"
$PW_COMMAND < per.in > per.out
check_failure $?
$ECHO " done"

# projection for parallel configuration 
cat > proj_par.in << EOF
 &projwfc
    outdir = '$TMP_DIR/',
    prefix='par'
    Emin = -25.0
    Emax=25.0
    DeltaE=0.01
    degauss = 0.005
    ngauss = -1
    lsym = .false.
    filproj = 'eband_par.dat'
    ef_0 = -0.454721315571854  
    lforcet = .true.
 /
EOF
$ECHO "  running projection for parallel configuration ...\c"
$PROJ_COMMAND < proj_par.in > proj_par.out
check_failure $?
$ECHO " done"

# projection for perpendicular configuration 
cat > proj_per.in << EOF
 &projwfc
    outdir = '$TMP_DIR/',
    prefix='per'
    Emin = -25.0
    Emax=25.0
    DeltaE=0.01
    degauss = 0.005
    ngauss = -1
    lsym = .false.
    filproj = 'eband_per.dat'
    ef_0 = -0.454721315571854
    lforcet = .true.
 /
EOF
$ECHO "  running projection for perpendicular configuration ...\c"
$PROJ_COMMAND < proj_per.in > proj_per.out
check_failure $?
$ECHO " done"