#!/bin/bash
# Open media links in your preferred program, or browser as fallback

# Handlers and templates for common file extensions and media sites are below.
# You should change the defaults to your liking.
#
# Imgur support for indirect links (so any link not on i.imgur.com) is also
# available, using Imgur's API to determine wether you're trying to open an
# album or an image, then feeding all direct image links to either your
# gif handler for gifs, or image handler for images.
# If you intend to use this feature often, please replace the imgur client id
# below with yours, because API requests are limited for each one.
# You can get your own client id here: https://api.imgur.com/oauth2/addclient
#
# This script assumes that your image and video players support direct links
# as opposed to local files, but if they don't you can simply remove any sites
# or file extensions in the templates below and use the -d or --detect flag;
# they'll be downloaded to a temporary directory before being played (except
# for imgur.com and v.redd.it links).
# It also assumes that they support multiple links as arguments, instead of
# just one. There's no easy workaround for this though.


# Imgur client id
# Required for indirect imgur links
imgurClientId=""

# Temp file directory
tmpDir="/tmp/linkhandler"


## Handlers
# Images
imgHandler="feh"

# Gifs
gifHandler="mpv --quiet --loop"

# Videos
vidHandler="mpv --quiet"

# Download
dwnHandler="tsp wget"

# Fallback browser
browser="$TRUEBROWSER"


## Templates
# Images
imgFiles="png apng jpg jpeg jpe bmp tiff"
imgSites="i.imgur.com/
	\|i.redd.it/
	\|deviantart.com/
	\|tinypic.com/
	\|unsplash.com/photos/
	\|gyazo.com/
	\|prnt.sc/
	"

# Gifs
gifFiles="gif webm"
gifSites="gfycat.com/
	\|giphy.com/
	\|gph.is/
	\|gifbin.com/
	\|clips.twitch.tv/
	\|streamable.com/
	"

# Video
vidFiles="mkv mp4 mov mpv flv avi"
vidSites="youtube.com/watch
	\|youtube.com/embed/
	\|youtube.com/video/
	\|youtu.be/
	\|hooktube.com/
	\|bitchute.com/
	\|vimeo.com/
	\|liveleak.com/
	\|twitch.tv/
	\|neatclip.com/
	"

# Download
dwnFiles="pdf csv doc docx xls xlsx ppt pptx mp3 flac opus ogg aac"
dwnSites="raw.githubusercontent.com/"

# Browser
brwFiles="htm html shtm shtml php asp aspx"
brwSites="reddit.com/
	\|wikipedia.org/
	\|archlinux.org/
	\|wiki.gentoo.org/
	\|twitter.com/
	\|github.com/
	\|stackoverflow.com/
	\|stackexchange.com/
	\|superuser.com/
	"


### Functions
# Usage
usage() {
	cat << EOF
USAGE
   $(basename "$0") [OPTIONS] URLS...

OPTIONS
   -h, --help        Print help and exit.
   -d, --detect      Detect link type instead of opening in browser.
                     (it will then be opened in the appropiate handler)
   -v, --verbose     Print progress as links are being processed.
EOF
}

# Print to stdout if verbose mode is enabled
printMessage() {
	if [[ -n $verbose ]]; then
		echo -e "$@"
	fi
}

# Check dependecies
checkDep() {
	if ! command -v "$1" > /dev/null; then
		echo "$(basename "$0"): \"$1\" isn't installed!" >&2
		return 1
	fi
}

# Determine appropiate handler based on filetype
# Indirect links will usually be opened in the browser,
# unless you add the site to one of the templates above.
detectLinkType() {
	# Download file
	mkdir -p "${tmpDir:-/tmp/linkhandler}"
	tmp="$(mktemp -d "${tmpDir:-/tmp/linkhandler}/XXXXXXXX")/$(basename "$1")"
	checkDep wget && wget -q -O "$tmp" -- "$1"

	# Detect mime type
	case "$(file -b --mime-type "$tmp" 2>/dev/null)" in
		image/gif|video/webm)
			printMessage "Link type: Gif"
			gifQueue+=( "$tmp" )
			;;
		image/*)
			printMessage "Link type: Image"
			imgQueue+=( "$tmp" )
			;;
		video/*|audio/*)
			printMessage "Link type: Video"
			vidQueue+=( "$tmp" )
			;;
		*)
			printMessage "Link type: Browser"
			brwQueue+=( "$1" )
			;;
	esac
}

## Imgur
# Send Imgur API request
imgurReq() {
	checkDep curl &&
		curl -s -H "Authorization: Client-ID $imgurClientId" \
			  -- "https://api.imgur.com/3/$1/${2##*/}"
}

# Queue Imgur links into the appropiate handler's queue
# Turns all animated formats into mp4
imgurQueue() {
	# For indirect imgurCheck links
	if [[ $1 == -i ]]; then
		local indirectLink="true"
		unset printNewline
		shift 1
	fi

	for link; do
		[[ -n $indirectLink ]] && printMessage "Link: $link"
		[[ $link =~ \?.+$ ]] && link="${link%\?*}"

		# Gif
		if [[ "${link##*.}" =~ ^(gif|gifv|mov|mp4)$ ]]; then
			printMessage "Link type: Gif"
			[[ -n $indirectLink ]] && printMessage
			gifQueue+=( "${link%.*}.mp4" )

		# Image
		elif [[ "${link##*.}" =~ ^(jpg|jpeg|png|apng|tiff)$  ]]; then
			printMessage "Link type: Image"
			[[ -n $indirectLink ]] && printMessage
			imgQueue+=( "$link" )

		# Indirect link
		else
			printMessage "Link type: Indirect Imgur link. Detecting type..."
			imgurCheckQueue+=( "$link" )
		fi
	done
}

# Determine wether Imgur link is of an album or an image,
# then add it to the respective handler's queue
imgurCheck() {
	for link; do
		# Album
		if imgurReply="$(imgurReq album "$link")" &&
		[[ $(echo "$imgurReply" | jq -j '.status') = 200 ]]; then
			printMessage "Imgur link type: Album\n"
			imgurLinks="$(echo "$imgurReply" | jq -r '.data.images[].link')"
			imgurQueue -i $imgurLinks

		# Single image/gif
		elif imgurReply="$(imgurReq image "$link")" &&
		[[ $(echo "$imgurReply" | jq -j '.status') = 200 ]]; then
			printMessage "Imgur link type: Single image/gif\n"
			imgurLinks="$(echo "$imgurReply" | jq -r '.data.link')"
			imgurQueue -i $imgurLinks

		# Invalid link
		else
			echo "Error: Invalid Imgur link!" >&2
		fi
	done
}


## Flags
[[ $# = 0 ]] && { ${browser:-usage}; exit 0; }
checkDep getopt &&
	eval set -- $(getopt -o "h,d,v" -l "help,detect,verbose" \
	                     -n "$(basename "$0")" -- "$@")
while true; do
	case "$1" in
		-h|--help)
			usage
			exit 0
			;;
		-d|--detect)
			detect="true"
			shift 1
			;;
		-v|--verbose)
			verbose="true"
			shift 1
			;;
		--)
			shift 1
			break
			;;
	esac
done

## Parse links
for arg; do
	printMessage "Link: $arg"
	printNewline="true"
	ext="${arg##*.}"

	# Embedded markdown link
	if [[ $arg =~ \]\(https?://.+ ]] && checkDep sed; then
		arg="$(echo "$arg" | sed -E 's|.*\]\((https?://.+)|\1|; s|\)$||')"
	fi

	# Imgur image/gif/album
	if [[ $arg =~ imgur\.com/.+ ]]; then
		imgurQueue "$arg"

		# Indirect link
		if [[ -n $imgurCheckQueue ]] && checkDep jq; then
			if [[ -n $imgurClientId ]]; then
				imgurCheck ${imgurCheckQueue[@]}
			else
				echo "Error: Imgur client id not set!" >&2
				printMessage "Link type: Browser"
				brwQueue+=( "$arg" )
			fi
		fi

	# Reddit gif/video
	elif [[ $arg =~ v\.redd\.it/[a-z0-9]+ ]]; then
		printMessage "Link type: Gif"
		gifQueue+=( "${arg%/DASHPlaylist.mpd}/DASHPlaylist.mpd" )

	# Gif
	elif echo "$arg" | grep -q "$gifSites" ||
	echo "$gifFiles" | grep -q "${ext%%\?*}"; then
		printMessage "Link type: Gif"
		gifQueue+=( "$arg" )

	# Image
	elif echo "$arg" | grep -q "$imgSites" ||
	echo "$imgFiles" | grep -q "${ext%%\?*}"; then
		printMessage "Link type: Image"
		imgQueue+=( "$arg" )

	# Video
	elif echo "$arg" | grep -q "$vidSites" ||
	echo "$vidFiles" | grep -q "${ext%%\?*}"; then
		printMessage "Link type: Video"
		vidQueue+=( "$arg" )

	# Download
	elif echo "$arg" | grep -q "$dwnSites" ||
	echo "$dwnFiles" | grep -q "${ext%%\?*}"; then
		printMessage "Link type: Download"
		dwnQueue+=( "$arg" )

	# Browser
	elif echo "$arg" | grep -q "$brwSites" ||
	echo "$brwFiles" | grep -q "${ext%%\?*}" ||
	[[ -z $detect ]]; then
		printMessage "Link type: Browser"
		brwQueue+=( "$arg" )

	# Detect link type
	else
		printMessage "Detecting link type..."
		detectLinkType "$arg"
	fi

	# Newline at the end
	if [[ -n $printNewline ]]; then
		printMessage
		unset printNewline
	fi
done


## Open queued links
printMessage "Opening links..."

# Image
if [[ -n $imgQueue ]] && checkDep ${imgHandler%%\ *}; then
	$imgHandler ${imgQueue[@]} &disown
fi

# Gif
if [[ -n $gifQueue ]] && checkDep ${gifHandler%%\ *}; then
	$gifHandler ${gifQueue[@]} &disown
fi

# Video
if [[ -n $vidQueue ]] && checkDep ${vidHandler%%\ *}; then
	$vidHandler ${vidQueue[@]} &disown
fi

# Download
if [[ -n $dwnQueue ]] && checkDep ${dwnHandler%%\ *}; then
	$dwnHandler ${dwnQueue[@]} &disown
fi

# Browser
if [[ -n $brwQueue ]] && checkDep ${browser%%\ *}; then
	$browser ${brwQueue[@]} &disown
fi