bang!

#!/bin/sh -e

help() {
	cat - >&2 <<EOF
This script emulates DuckDuckGo's "bangs" feature, but better:

1. Links are generated locally, which saves time, esp. on slow connections.

2. Fully configurable/extensible. New bangs can be defined in ~/.bangs,
described below. The default bang can also be changed with the DEFAULT_BANG
environment variable.

3. The generated links point to non-JS versions/mirrors of sites when available.

4. Links can be generated for non-HTTP resources, such as Gopher.

Examples:

bang! what is a cat?
bang! !w cat
bang! !wes gato  # Spanish-Wikipedia page for cat
bang! !yt cat videos

Environment variables used by this script:

BROWSER: (default: xdg-open)
	The command that will be used to open the link. You may want to set
	this to your preferred web browser. Set to "echo" to just print the
	link to standard output.

DEFAULT_BANG: (default: !duckduckgo)
	The default bang if no bang is provided.

NITTER_MIRRORS:
	Nitter mirrors used by !tw and !twitter, URLs must end with /

INVIDIOUS_MIRRORS:
	Invidious mirrors used by !yt and !youtube, URLs must end with /

The ~/.bangs (or \$BANGS) file:
	This file allows you to define your own bangs which take priority
	over this script's builtin bangs. The location of the file can be
	overriden with the \$BANG variable. Here's an example:

	case "\$bang" in
		!g) link="https://www.google.com/search?q=\$*" ;;
		!a) link="https://www.amazon.com/s/?field-keywords=\$*" ;;
	esac
EOF
}

case "$1" in
	-h|--help) help; exit 0 ;;
	'') exit 0 ;;
	!*) bang="$1"; shift 1 ;;
	*) bang="${DEFAULT_BANG:-!duckduckgo}" ;;
esac

if [ -r "${BANGS:=${HOME:?}/.bangs}" ]; then
	. "$BANGS" "$@"
fi

# each URL must end with /
: ${NITTER_MIRRORS='https://bird.trom.tf/
https://birdsite.xanny.family/
https://n.0x0.st/
https://n.hyperborea.cloud/
https://nitter.1d4.us/
https://nitter.alefvanoon.xyz/
https://nitter.autarkic.org/
https://nitter.ca/
https://nitter.domain.glass/
https://nitter.eu/
https://nitter.fdn.fr/
https://nitter.grimneko.de/
https://nitter.ir/
https://nitter.it/
https://nitter.koyu.space/
https://nitter.mailstation.de/
https://nitter.moomoo.me/
https://nitter.namazso.eu/
https://nitter.net/
https://nitter.nixnet.services/
https://nitter.pussthecat.org/
https://nitter.unixfox.eu/
https://nitter.vxempire.xyz/
https://twitter.076.ne.jp/
https://twitter.censors.us/'}

# each URL must end with /
: ${INVIDIOUS_MIRRORS='https://invidious.namazso.eu/
https://vid.puffyan.us/
https://yewtu.be/
https://yt.artemislena.eu/'}

#
# these are sorted alphabetically, please try to maintain this
#
# in Vim you can sort this by putting your cursor on the first bang,
# C-v, and then putting cursor on the last bang, and then :sort
#
# each bang is restricted to one line so it's easier to sort
#
if [ ! "$link" ]; then
case "$bang" in
!alpine) link="https://pkgs.alpinelinux.org/packages?name=$*" ;;
!alpinewiki) link="https://wiki.alpinelinux.org/w/index.php?search=$*" ;;
!archaur|!aur) link="https://aur.archlinux.org/packages.php?K=$*" ;;
!archive) link="https://archive.org/search.php?query=$*" ;;
!archived|!wayback|!wb|!wbm) link="https://web.archive.org/web/*/$*" ;;
!archlinux) link="https://bbs.archlinux.org/search.php?keywords=$*" ;;
!archpkg|!archpackages) link="https://www.archlinux.org/packages/?q=$*" ;;
!aw|!arch|!archwiki) link="https://wiki.archlinux.org/index.php/$*" ;;
!a|!amazon) link="https://www.amazon.com/s/?field-keywords=$*" ;;
!ddg|!duckduckgo) link="https://duckduckgo.com/lite?q=$*" ;;
!deb) link="https://packages.debian.org/search?keywords=$*" ;;
!debian) link="https://search.debian.org/cgi-bin/omega?DB=en&P=$*" ;;
!e|!ebay) link="https://www.ebay.com/sch/i.html?_nkw=$*" ;;
!gb) link="https://www.google.com/search?q=$*&tbm=bks" ;;
!gentoopkg|!gentoopackage) link="https://packages.gentoo.org/packages/search?q=$*" ;;
!gentoo|!gentoowiki) link="https://wiki.gentoo.org/?search=$*" ;;
!gh|!github) link="https://github.com/search?q=$*" ;;
!gi) link="https://www.google.com/search?q=$*&tbm=isch" ;;
!gm) link="https://www.google.com/maps/search/$*" ;;
!gn) link="https://news.google.com/search?q=$*" ;;
!gp|!gw|!gopherpedia) link="gopher://gopherpedia.com/7/lookup%09$*?" ;;
!gs) link="https://www.google.com/search?q=$*&tbm=shop" ;;
!gt) link="https://translate.google.com/?text=$*" ;;
!gv) link="https://www.google.com/search?q=$*&tbm=video" ;;
!g|!google) link="https://www.google.com/search?q=$*" ;;
!hackage) link="https://hackage.haskell.org/packages/search?terms=$*" ;;
!hn|!hackernews) link="https://hn.algolia.com/?q=$*" ;;
!h|!hoogle) link="https://hoogle.haskell.org/?hoogle=$*" ;;
!imdb) link="https://www.imdb.com/find?q=$*" ;;
!lt|!limetorrents) IFS=-; link="https://www.limetorrents.pro/search/all/$*/" ;;
!lw|!legwork) link="http://legwork.i2p/yacysearch.html?query=$*" ;;
!man|!debman) link="https://manpages.debian.org/jump?q=$*" ;;
!nethack) link="https://nethackwiki.com/wiki/?search=$*" ;;
!nyaa) link="https://nyaa.si/?f=0&c=0_0&q=$*" ;;
!phoronix) link="https://www.phoronix.com/scan.php?page=search&q=$*" ;;
!pm|!postman) link="http://tracker2.postman.i2p/?search=$*" ;;
!p|!pinterest) link="https://www.pinterest.com/search/pins/?q=$*" ;;
!r|!reddit) link="https://old.reddit.com/search?q=$*" ;;
!so|!stackoverflow) link="https://stackoverflow.com/search?q=$*" ;;
!ste|!steam) link="https://store.steampowered.com/search/?term=$*" ;;
!tgb|!thegopherbay) link="gopher://bay.parazy.de:666/7/q.dcgi?%09$*" ;;
!tpb10|!thepiratebay10) link="https://thepiratebay10.org/search/$*" ;;
!tpbl|!piratebaylive) link="https://piratebay.live/search/$*" ;;
!tpb|!thepiratebay) link="https://thepiratebay.org/search.php?q=$*" ;;
!twitch) link="https://www.twitch.tv/$*" ;;
!twitchg) link="https://www.twitch.tv/directory/game/$*" ;;
!tw|!twitter) link="$(printf '%s\n' "$NITTER_MIRRORS" | shuf | head -n 1)search?q=$*" ;;
!v|!veronica) link="gopher://gopher.floodgap.com:70/7/v2/vs?%09$*" ;;
!w) link="https://wikipedia.org/w/index.php?search=$*&ns0=1" ;;
!w??) link="https://${bang#!w}.wikipedia.org/w/index.php?search=$*&ns0=1" ;;
!wa|!wolf|!wolfram) link="https://www.wolframalpha.com/input/?i=$*" ;;
!wt) link="https://wiktionary.org/wiki/$*" ;;
!wt??) link="https://${bang#!wt}.wiktionary.org/wiki/$*" ;;
!yt|!youtube) link="$(printf '%s\n' "$INVIDIOUS_MIRRORS" | shuf | head -n 1)search?q=$*" ;;
!zillow) link="https://www.zillow.com/homes/$*_rb" ;;
*)
	printf '%s\n' "unknown bang $bang" >&2
	help
	exit 1
	;;
esac
fi

eval exec "${BROWSER:-xdg-open}" '"$link"'