cnf: CLI for https://command-not-found.com

README.md

@@ -19,6 +19,7 @@ will create the symbolic link for each script in the \<path> directory.
 
 ## Shell
 
+- [cnf](scripts/cnf) is a command line interface for [command-not-found website](https://command-not-found.com).
 - [dus](scripts/dus) shows the directories' sizes sorted in descending order (see also [dust](https://github.com/bootandy/dust)).
 - [ext](scripts/ext) unpacks archives.
 - [pk](scripts/pk) creates archives of various types.

scripts/cnf

@@ -0,0 +1,43 @@
+#!/bin/bash
+
+# CLI for https://command-not-found.com.
+
+trim() {
+	tr -d '\n'
+}
+
+die() {
+	echo "$*" >&2
+	exit 1
+}
+
+xpath() {
+	xmllint --html --xpath "$1" - 2>&-
+}
+
+if [ -z "$1" ]; then
+	die "USAGE: $(basename "$0") COMMAND_NAME"
+fi
+
+CNF_PAGE=$(curl -sq -L "command-not-found.com/$1")
+
+CMD_NAME=$(xpath '//*[contains(@class, "row-command-info")]/div/h2/text()' <<<"$CNF_PAGE" | trim)
+
+[ -z "$CMD_NAME" ] && die "Command '$1' not found."
+
+CMD_DESCRIPTION=$(xpath '(//*[contains(@class, "row-command-info")]/div/p)[1]/text()' <<<"$CNF_PAGE" \
+	| trim | sed -E 's/(.)\.(.)/\1. \2/g' | fmt -s -w 60)
+
+OS_LIST=$(xpath '//*[contains(@class, "card-body")]/dl/div/dt/text()' <<<"$CNF_PAGE"  \
+	| sed -E '/^$/d; s/^[[:space:]]+//')
+
+INSTALL_CMDS=$(xpath '//div[@class="card-body"]/dl/div/dd/code' <<<"$CNF_PAGE" \
+	| sed -E -e $'s/></>\\\n</g; s/<\/?code>//g')
+
+# ------------------------------------------------------------------------------
+
+echo -e "# $CMD_NAME\n"
+echo -e "$CMD_DESCRIPTION\n"
+
+paste <(echo "$OS_LIST") <(echo "$INSTALL_CMDS") --delimiter '@' | column -t -s '@'
+