feat(scripts): pimp rfc script

.bin/rfc.sh

@@ -1 +0,0 @@
-curl -sSL "https://tools.ietf.org/rfc/rfc$*.txt" | less

configs/packages/default.nix

@@ -144,6 +144,7 @@ in {
     scripts.liddel-scott-jones
     # kmein.slide
     scripts.tolino-screensaver
+    scripts.rfc
     nix-prefetch-git
     scripts.nix-git
     nixfmt

packages/scripts/default.nix

@@ -302,6 +302,11 @@ in rec {
 
   unicodmenu = pkgs.callPackage ./unicodmenu.nix { };
 
+  rfc = wrapScript {
+    script = ./rfc.sh;
+    name = "rfc";
+    packages = [ pkgs.curl pkgs.pup pkgs.gnused pkgs.gawk pkgs.gnugrep pkgs.fzf ];
+  };
 
   bvg = pkgs.callPackage ./bvg.nix { };
   nav = pkgs.callPackage ./nav.nix { };

packages/scripts/rfc.sh

@@ -0,0 +1,24 @@
+#!/bin/sh
+set -efu
+
+cache_file=/tmp/rfc-index.txt
+
+fetch_index() {
+  if [ -f "$cache_file" ]
+  then cat "$cache_file"
+  else curl -sSL https://tools.ietf.org/rfc/index | tee "$cache_file"
+  fi
+}
+
+rfc_list="$(fetch_index \
+  | pup 'pre text{}' \
+  | awk '$0 != "" {printf "%s",$0} $0 == "" {printf "\n"}' \
+  | sed 's/\s\+/ /g' \
+  | sed 'n;d' \
+  | grep '^RFC[[:digit:]]' \
+  | sed 's/RFC\([[:digit:]]\+\)/\1\t/;s/\. .*//'
+)"
+
+selection="$(echo "$rfc_list" | fzf | awk '{print $1}')"
+
+curl -sSL "https://tools.ietf.org/rfc/rfc$selection.txt" | less