#!/bin/bash

# Usage: loc_x <LAMMPS input file> <atom #>
loc_x() { cat $1|grep "^$2\s*[0-9]"|
					sed "s/^$2\s*1\s*\([-0-9.]*\)\s*[-0-9.]*\s*[-0-9.]*\s*/\1/"; }
loc_y() { cat $1|grep "^$2\s*[0-9]"|
					sed "s/^$2\s*1\s*[-0-9.]*\s*\([-0-9.]*\)\s*[-0-9.]*\s*/\1/"; }


# Usage: 
# pullout <LAMMPS input file> "<atom #> <atom #> ..." <x displacement> <y disp>
#
#	Return LAMMPS input file text after adding displacement*sin(theta) to
# y coord, and displacement*cos(theta) to the x coord, of indicated atom #.
pullout() {
	if [[ $3 == 0 && $4 == 0 ]]; then exit 0; fi
	count=0
	echo $2: $3, $4 > outputsomething
	for atom in $2; do
		((count++))
		newloc_x=$(bc <<< "$(loc_x $1 $2) + $3")
		newloc_y=$(bc <<< "$(loc_y $1 $2) + $4")

		# echo $1 $2 $3 $4 > /dev/stderr
		cat $1|sed "s/^\($2\s*1\s*\)\([-0-9.]*\)\(\s*\)\([-0-9.]*\)\(\s*\)\([-0-9.]*\)\(\s*$\)/\1${newloc_x}\3${newloc_y}\5\6\7/" > cmd.pullout.tmp.$count
	done
	echo cmd.pullout.tmp.$count
	rm -f cmd.pullout.tmp.* >> /dev/null 2> /dev/null
}


# Usage: get_pulled_atoms <LAMMPS input file>
#
# Return a list of atoms from LAMMPS group "pulled" from LAMMPS input file.
get_pulled_atoms() {
#	grep 'group' $1|grep 'pulled'|sed 's/^.*id[\s]*\([0-9\s]*\)[\s]*$/\1/'
	grep 'group' $1|grep 'pulled'|sed 's/[^0-9\s]?/'
}


# Usage: convert_to_pull_displacement <value> <order>
#
# Converts int to a decimal number in angstroms where int is 1/order angstroms.
convert_to_pull_displacement() {
	echo $(bc <<< "scale=2; $1 / $2"|
		sed 's/^\([0-9]\)*$/\1\.00/'|
		sed 's/\.\([0-9]\)\s*$/\.\10/'|
		sed 's/^\./0\./')
}



#	Print the three-dimensional extremes of the atom coordinates in a LAMMPS
# input file.

# Usage: print_extremes <LAMMPS input file>
# Output: <x_min> <x_max> <y_min> <y_max> <z_min> <z_max>
print_extremes() {
	input_file=$1
	found_atoms="false"
	while read -r line; do
		if [[ $found_atoms == "false" ]]; then
			if [[ $line == "Atoms" ]]; then	found_atoms="true"; fi
			continue
		fi
		atom_num=$(echo $line|sed 's/^\s*\([0-9]*\).*/\1/')
		x_cur=$(echo $line|sed 's/^\s*[0-9]\+\s\+[0-9]\+\s\+\([0-9.-]\+\).*$/\1/')
		y_cur=$(echo $line|sed 's/^\s*[0-9]\+\s\+[0-9]\+\s\+[0-9.-]\+\s*\([0-9.-]\+\).*$/\1/')
		z_cur=$(echo $line|sed 's/^\s*[0-9]\+\s\+[0-9]\+\s\+[0-9.-]\+\s*[0-9.-]\+\s*\([0-9.-]\+\)\s*$/\1/')
		if [[ ! $atom_num -ge 1 ]]; then continue; fi
		if [[ $atom_num == "1" ]]; then
			x_max=$x_cur; x_min=$x_cur
			y_max=$y_cur; y_min=$y_cur
			z_max=$z_cur; z_min=$z_cur
		fi
		if [[ $(bc <<< "$x_cur > $x_max") == "1" ]]; then
			x_max=$x_cur
		fi
		if [[ $(bc <<< "$x_cur < $x_min") == "1" ]]; then
			x_min=$x_cur
		fi
		if [[ $(bc <<< "$y_cur > $y_max") == "1" ]]; then
			y_max=$y_cur
		fi
		if [[ $(bc <<< "$y_cur < $y_min") == "1" ]]; then
			y_min=$y_cur
		fi
		if [[ $(bc <<< "$z_cur > $z_max") == "1" ]]; then
			z_max=$z_cur
		fi
		if [[ $(bc <<< "$z_cur < $z_min") == "1" ]]; then
			z_min=$z_cur
		fi
	done < $input_file
	echo "$x_min $x_max $y_min $y_max $z_min $z_max"
}