#!/usr/bin/env bash
# This file can be sourced or executed.
# More information below at the "Execution" section

# Todo Function
function todo(){
	local conf="${HOME}/.config/.todo"
	local iterVal mode array
	[[ -f "${conf}" ]] ||
	cat /dev/null > "${conf}"
	sed -i '/^\s*$/d' "${conf}"
	sed -i '/^$/d' "${conf}"
	case "$1" in
		-h|--help)	mode=0 ;;
		-r|--remove)	mode=1 ;;
		-a|--add)	mode=2 ;;
		*[0-9]*)	mode=3 ;;
		-q|--quiet)	mode=4 ;;
		*)		mode=5 ;;
	esac
	if [[ "${mode}" =~ ^[0-5]$ ]]; then
		if [[ "${mode}" -eq 0 ]]; then
			cat << EOF

@Usage:	todo [INDEX]...
     	todo [OPTIONS [INDEX|ITEM]...]...
List, add, or remove todo items.

@OPTIONS:
	-h,--help	This help message.
	-r,--remove	Remove an item by INDEX number. 
	-a,--add	Add an item by ITEM.
	-q,--quiet	No error messages.
@INDEX:
	Integers	Index number of item.
@ITEM:
	String		Todo ITEM.
@EXAMPLES:
	todo 		
		List all items in todo list.
	todo 1
		List 1st ITEM in todo list. 
	todo -a "Something to do"
		Add a todo item.
	todo -r 1
		Remove item at index #1.

EOF
		elif [[ "${mode}" -eq 1 ]]; then
			sed -i -e "${2}d" "${conf}"
			return
		elif [[ "${mode}" -eq 2 ]]; then
			echo "$2" >> "${conf}"
			return
		elif [[ "${mode}" -eq 3 ]]; then
			readarray -t array < "${conf}"
			echo "${array[$((${1} - 1))]}"
			return
		else
			readarray -t array < "${conf}"
			if [[ ${#array[@]} -eq 0 ]]; then
				[[ ${mode} -ne 4 ]] &&
				echo "No items in the TODO list."
				return
			fi
			for iterVal in "${!array[@]}"; do
				echo "[$((${iterVal} + 1))]:${array[${iterVal}]}"
			done
			return
		fi
	fi
}
$(return >/dev/null 2>&1)
if [ "$?" -eq "0" ]; then
	complete -W '-h --help -r --remove -a --add -q --quiet' todo
else
	todo "$@"
fi