#!/bin/bash

# Copyright (c) 2020 jm1hey
#
# Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

# Version
script_version="1.5"

# The purpose of this script is described in the 'printhelp' function defined below.

# define command name -- this should be the same as the script file name
cmdname="srchbin"

# define usage and help functions
function printusage {
	echo \
"
Usage: $cmdname SEARCH_TERM [OPTION(s)]

Options:
	--help
		Print help information and exit

	--version
		Print version information and exit

	--case-sensitive | -c
		Make the search case-sensitive

	--full-path | -f
		Print each result as a full path

"
}

function printhelp {
	echo \
"
$cmdname is a Bash script that searches the locations specified
in the current environment PATH variable for files whose names
contain a given search term. It is useful for determining
forgotten command names and finding unknown commands."
	printusage
}

function printversion {
	echo "$script_version"
}

# check for sufficient number of arguments
if [ $# -lt 1 ]
then
	printusage
	exit 1
fi

# check for "--help" argument
for i in "$@"
do
	if [ "$i" == "--help" ]
	then
		# print help text
		printhelp
		exit 0
	fi
done

# check for "--version" argument
for i in "$@"
do
	if [ "$i" == "--version" ]
	then
		printversion
		exit 0
	fi
done

# process arguments
## check for "--case-sensitive"
num_i=1
for i in "$@"
do
	if [ "$i" == "--case-sensitive" ] || [ "$i" == "-c" ]
	then
		case_sens=1
		argvalid[$num_i]=1
	fi
	num_i=$((num_i+1))
done
if [ -z "$case_sens" ]
then
	# default
	case_sens=0
fi

## check for "--full-path"
num_i=1
for i in "$@"
do
	if [ "$i" == "--full-path" ] || [ "$i" == "-f" ]
	then
		full_path=1
		argvalid[$num_i]=1
	fi
	num_i=$((num_i+1))
done
if [ -z "$full_path" ]
then
	# default
	full_path=0
fi

# get search term
num_i=1
for i in "$@"
do
	if [ "${i:0:1}" != "-" ] && [ -z $search_term_found ]
	then
		search_term="$i"
		search_term_found=1
		argvalid[$num_i]=1
	fi
	num_i=$((num_i+1))
done

# reject invalid arguments
num_i=1
for i in "$@"
do
	if [ "${argvalid[$num_i]}" != 1 ]
	then
		printf "Invalid argument: \"%s\"\n" "$i"
		invalid_arg=1
	fi
	num_i=$((num_i+1))
done
if ! [ -z $invalid_arg ]
then
	exit 1
fi

# process settings
if [ $case_sens == 1 ]
then
	namearg="name"
else
	namearg="iname"
fi

# loop through PATH directories
IFS=":"
for pathdir in $PATH
do
	if ! [ -d "$pathdir" ]
	then
		continue
	fi
	unset IFS
	for result in $(find "$pathdir" -maxdepth 1 -"$namearg" "*""$search_term""*" "!" -type d)
	do
		if [ $full_path == 1 ]
		then
			echo "$result"
		else
			echo "${result##*/}"
		fi
	done
	IFS=":"
done
unset IFS