#!/bin/sh
#
# todo - operate on a todo.txt file
#
# SPDX-FileCopyrightText: 2023 Daniel Kalak
# SPDX-License-Identifier: GPL-3.0-or-later

todotxt="${TODOTXT:-"${HOME:?}/todo"}"
donetxt="${DONETXT:-"${HOME:?}/done"}"
editor="${EDITOR:-nano}"

usage() {
	cat <<- EOF >&2
	Usage:
	    $(basename "$0") COMMAND
	Commands:
	    h|help:              Show this information
	    [show]:              Page todo, sorted
	    r|random [N]:        Print N (5) random lines from todo, sorted
	    e|edit:              Edit todo
	    s|sort:              Sort todo in-place
	    d|done:              Page x tasks (from todo and done), sorted
	    x|extract:           Move x tasks from todo to done
	    p|projects:          Print project tags in todo, sorted
	    c|contexts:          Print context tags in todo, sorted
	    [--|search] PATTERN: Print lines in todo matching PATTERN, sorted
	Environment:
	    todo: using "$todotxt", change with TODOTXT
	    done: using "$donetxt", change with DONETXT
	    editor: using "$editor", change with EDITOR
	EOF
}

search() {
	grep -e "$1" "$todotxt" | LC_ALL=C sort
}

case "$1" in
h|help)
	usage
	;;
''|show)
	LC_ALL=C sort "$todotxt" | less
	;;
r|random)
	shuf -n "${2:-5}" "$todotxt" | LC_ALL=C sort
	;;
e|edit)
	exec $editor "$todotxt"
	;;
s|sort)
	temp="$(mktemp)"
	LC_ALL=C sort "$todotxt" > "$temp"
	mv -i "$temp" "$todotxt"
	;;
d|'done')
	if [ -f "$donetxt" ]
	then grep '^x ' "$todotxt" | cat - "$donetxt" | LC_ALL=C sort | less
	else grep '^x ' "$todotxt" | LC_ALL=C sort | less
	fi
	;;
x|extract)
	grep '^x ' "$todotxt" >> "$donetxt"
	temp="$(mktemp)"
	grep -v '^x ' "$todotxt" > "$temp"
	mv "$temp" "$todotxt"
	;;
p|projects)
	grep -o '+[^ ]*' "$todotxt" | LC_ALL=C sort | uniq
	;;
c|contexts)
	grep -o '@[^ ]*' "$todotxt" | LC_ALL=C sort | uniq
	;;
--|search)
	search "$2"
	;;
*)
	search "$1"
	;;
esac