dman

#!/bin/sh

progname=$(basename $0)

main () { parse_opts "$@"
	if [ "$terminal" = true ]; then
		apropos . | fzf | cut -d " " -f 1-2 | tr -d " " | xargs -I {} man '{}'
		exit $?
	fi

	directory=/tmp/$progname

	cleanup() { rm -rf $directory; }
	trap cleanup EXIT
	trap exit INT HUP TERM

	[ ! -d "$directory" ] && mkdir $directory
	title="$(apropos . | dmenu -l 10 | cut -d " " -f 1-2 | tr -d " ")"
	[ "$title" = "" ] && exit 1

	files="$(for i in $title; do
		file="$directory/$i – $(printf '%s' "$i" | xargs -r man | head -1 |
			tr -s " " | cut -d " " -f 2- | rev | cut -d " " -f 2- | rev |
			# Straight apostrophes with non-whitespace characters surrounding them:
			# https://unix.stackexchange.com/a/713841/513913
			sed -e :1 -e "s/\([^[:space:]]\)'\([^[:space:]]\)/\1’\2/g" -e t1 |
			sed "s/'/‘/ ; s/'/’/")"

		printf '%s' "$i" | xargs -r man -Tpdf > "$file"
		[ -s "$file" ] && printf '%s\n' "$file"
	done)"

	if [ -z "$READER" ]; then
		if [ ! -x "$(command -v xdg-mime)" ]; then
			printf "$progname: %s\n" '`$READER` is not set and xdg-utils is not installed.' >&2
			exit 1
		fi
		READER="$(xdg-mime query default application/pdf | sed s/\.desktop$//)"
	fi

	printf '%s' "$files" | sed -e "s|'|'\\\\''|g ; s|\(.*\)|'\1'|" | xargs $READER
}

help() { printf "Usage:\t%s" "$progname [option]

Options:

Modes:
-t|--terminal  │ Use the terminal user interface (fzf and man)
-g|--graphical │ Use the graphical user interface (dmenu and PDF) (default)

-h|--help      │ Print this help message and exit
"; }

parse_opts() {
	while getopts htg- OPT; do
		if [ "$OPT" = "-" ]; then
			OPT="${OPTARG%%=*}"
			OPTARG="${OPTARG#$OPT}"
			OPTARG="${OPTARG#=}"
		fi
		case "$OPT" in
			h | help) help ; exit 0 ;;
			t | terminal) terminal=true ;;
			g | graphical) graphical=true ;;
			??*) printf "%s\n" "Illegal option --$OPT" >&2 ; exit 2 ;;
			?) exit 2 ;;
		esac
	done
	shift $((OPTIND-1))

	[ "$graphical" != true -a "$terminal" != true ] && graphical=true
}

main "$@"