#!/usr/bin/env bash

set -o noclobber -o noglob -o nounset -o pipefail
IFS=$'\n'

## If the option `use_preview_script` is set to `true`,
## then this script will be called and its output will be displayed in ranger.
## ANSI color codes are supported.
## STDIN is disabled, so interactive scripts won't work properly

## This script is considered a configuration file and must be updated manually.
## It will be left untouched if you upgrade ranger.

## Because of some automated testing we do on the script #'s for comments need
## to be doubled up. Code that is commented out, because it's an alternative for
## example, gets only one #.

## Meanings of exit codes:
## code | meaning    | action of ranger
## -----+------------+-------------------------------------------
## 0    | success    | Display stdout as preview
## 1    | no preview | Display no preview at all
## 2    | plain text | Display the plain content of the file
## 3    | fix width  | Don't reload when width changes
## 4    | fix height | Don't reload when height changes
## 5    | fix both   | Don't ever reload
## 6    | image      | Display the image `$IMAGE_CACHE_PATH` points to as an image preview
## 7    | image      | Display the file directly as an image

## Script arguments
FILE_PATH="${1}" # Full path of the highlighted file
PV_WIDTH="${2}"  # Width of the preview pane (number of fitting characters)
## shellcheck disable=SC2034 # PV_HEIGHT is provided for convenience and unused
PV_HEIGHT="${3}"        # Height of the preview pane (number of fitting characters)
IMAGE_CACHE_PATH="${4}" # Full path that should be used to cache image preview
PV_IMAGE_ENABLED="${5}" # 'True' if image previews are enabled, 'False' otherwise.

FILE_EXTENSION="${FILE_PATH##*.}"
FILE_EXTENSION_LOWER="$(printf "%s" "$FILE_EXTENSION" | tr '[:upper:]' '[:lower:]')"

## Settings
HIGHLIGHT_SIZE_MAX=262143 # 256KiB
HIGHLIGHT_TABWIDTH=${HIGHLIGHT_TABWIDTH:-8}
HIGHLIGHT_STYLE=${HIGHLIGHT_STYLE:-pablo}
HIGHLIGHT_OPTIONS="--replace-tabs=${HIGHLIGHT_TABWIDTH} --style=${HIGHLIGHT_STYLE} ${HIGHLIGHT_OPTIONS:-}"
PYGMENTIZE_STYLE=${PYGMENTIZE_STYLE:-autumn}
OPENSCAD_IMGSIZE=${RNGR_OPENSCAD_IMGSIZE:-1000,1000}
OPENSCAD_COLORSCHEME=${RNGR_OPENSCAD_COLORSCHEME:-Tomorrow Night}

handle_extension() {
	case "$FILE_EXTENSION_LOWER" in
	## Archive
	a | ace | alz | arc | arj | bz | bz2 | cab | cpio | deb | gz | jar | lha | lz | lzh | lzma | lzo | \
		rpm | rz | t7z | tar | tbz | tbz2 | tgz | tlz | txz | tZ | tzo | war | xpi | xz | Z | zip)
		atool --list -- "$FILE_PATH" && exit 5
		bsdtar --list --file "$FILE_PATH" && exit 5
		exit 1
		;;
	rar)
		## Avoid password prompt by providing empty password
		unrar lt -p- -- "$FILE_PATH" && exit 5
		exit 1
		;;
	7z)
		## Avoid password prompt by providing empty password
		7z l -p -- "$FILE_PATH" && exit 5
		exit 1
		;;

	## PDF
	pdf)
		## Preview as text conversion
		pdftotext -l 10 -nopgbrk -q -- "$FILE_PATH" - |
			fmt -w "$PV_WIDTH" && exit 5
		mutool draw -F txt -i -- "$FILE_PATH" 1-10 |
			fmt -w "$PV_WIDTH" && exit 5
		exiftool "$FILE_PATH" && exit 5
		exit 1
		;;

	## BitTorrent
	torrent)
		transmission-show -- "$FILE_PATH" && exit 5
		exit 1
		;;

	## OpenDocument
	odt | ods | odp | sxw)
		## Preview as text conversion
		odt2txt "$FILE_PATH" && exit 5
		## Preview as markdown conversion
		pandoc -s -t markdown -- "$FILE_PATH" && exit 5
		exit 1
		;;

	## XLSX
	xlsx)
		## Preview as csv conversion
		## Uses: https://github.com/dilshod/xlsx2csv
		xlsx2csv -- "$FILE_PATH" && exit 5
		exit 1
		;;

		# Markdown
	md)
		glow -s dark "${FILE_PATH}" && exit 5
		highlight --syntax=markdown --out-format=ansi "${FILE_PATH}" && exit 5
		bat "${FILE_PATH}" && exit 5
		exit 1
		;;

	## HTML
	htm | html | xhtml)
		## Preview as text conversion
		w3m -dump "$FILE_PATH" && exit 5
		lynx -dump -- "$FILE_PATH" && exit 5
		elinks -dump "$FILE_PATH" && exit 5
		pandoc -s -t markdown -- "$FILE_PATH" && exit 5
		;;

	## JSON
	json)
		jq --color-output . "$FILE_PATH" && exit 5
		python -m json.tool -- "$FILE_PATH" && exit 5
		;;

	## Direct Stream Digital/Transfer (DSDIFF) and wavpack aren't detected
	## by file(1).
	dff | dsf | wv | wvc)
		mediainfo "$FILE_PATH" && exit 5
		exiftool "$FILE_PATH" && exit 5
		;; # Continue with next handler on failure

	ini)
		cat "$FILE_PATH" && exit 5
		;;
	esac
}

handle_image() {
	## Size of the preview if there are multiple options or it has to be
	## rendered from vector graphics. If the conversion program allows
	## specifying only one dimension while keeping the aspect ratio, the width
	## will be used.
	local DEFAULT_SIZE="1920x1080"

	local mimetype="${1}"
	case "$mimetype" in
	## SVG
	image/svg+xml | image/svg)
		convert -- "${FILE_PATH}" "${IMAGE_CACHE_PATH}" && exit 6
		exit 1
		;;

	## DjVu
	# image/vnd.djvu)
	#     ddjvu -format=tiff -quality=90 -page=1 -size="${DEFAULT_SIZE}" \
	#           - "${IMAGE_CACHE_PATH}" < "${FILE_PATH}" \
	#           && exit 6 || exit 1;;

	## Image
	image/*)
		local orientation
		orientation="$(identify -format '%[EXIF:Orientation]\n' -- "$FILE_PATH")"
		## If orientation data is present and the image actually
		## needs rotating ("1" means no rotation)...
		if [[ -n "$orientation" && "$orientation" != 1 ]]; then
			## ...auto-rotate the image according to the EXIF data.
			convert -- "$FILE_PATH" -auto-orient "$IMAGE_CACHE_PATH" && exit 6
		fi

		## `w3mimgdisplay` will be called for all images (unless overriden
		## as above), but might fail for unsupported types.
		exit 7
		;;

	# Video
	video/*)
		# Thumbnail
		ffmpegthumbnailer -i "${FILE_PATH}" -o "${IMAGE_CACHE_PATH}" -s 0 && exit 6
		exit 1
		;;

	# PDF
	application/pdf)
		pdftoppm -f 1 -l 1 \
			-scale-to-x "${DEFAULT_SIZE%x*}" \
			-scale-to-y -1 \
			-singlefile \
			-jpeg -tiffcompression jpeg \
			-- "${FILE_PATH}" "${IMAGE_CACHE_PATH%.*}" &&
			exit 6 || exit 1
		;;

	## ePub, MOBI, FB2 (using Calibre)
	application/epub+zip | application/x-mobipocket-ebook | \
		application/x-fictionbook+xml)
		# ePub (using https://github.com/marianosimone/epub-thumbnailer)
		epub-thumbnailer "${FILE_PATH}" "${IMAGE_CACHE_PATH}" \
			"${DEFAULT_SIZE%x*}" && exit 6
		ebook-meta --get-cover="${IMAGE_CACHE_PATH}" -- "${FILE_PATH}" \
			>/dev/null && exit 6
		exit 1
		;;

	## Font
	application/font* | application/*opentype)
		preview_png="/tmp/$(basename "${IMAGE_CACHE_PATH%.*}").png"
		if fontimage -o "$preview_png" \
			--pixelsize "120" \
			--fontname \
			--pixelsize "80" \
			--text "  ABCDEFGHIJKLMNOPQRSTUVWXYZ  " \
			--text "  abcdefghijklmnopqrstuvwxyz  " \
			--text "  0123456789.:,;(*!?') ff fl fi ffi ffl  " \
			--text "  The quick brown fox jumps over the lazy dog.  " \
			"$FILE_PATH"; then
			convert -- "$preview_png" "$IMAGE_CACHE_PATH" &&
				rm "$preview_png" &&
				exit 6
		else
			exit 1
		fi
		;;

		## Preview archives using the first image inside.
		## (Very useful for comic book collections for example.)
		# application/zip|application/x-rar|application/x-7z-compressed|\
		#     application/x-xz|application/x-bzip2|application/x-gzip|application/x-tar)
		#     local fn=""; local fe=""
		#     local zip=""; local rar=""; local tar=""; local bsd=""
		#     case "${mimetype}" in
		#         application/zip) zip=1 ;;
		#         application/x-rar) rar=1 ;;
		#         application/x-7z-compressed) ;;
		#         *) tar=1 ;;
		#     esac
		#     { [ "$tar" ] && fn=$(tar --list --file "${FILE_PATH}"); } || \
		#     { fn=$(bsdtar --list --file "${FILE_PATH}") && bsd=1 && tar=""; } || \
		#     { [ "$rar" ] && fn=$(unrar lb -p- -- "${FILE_PATH}"); } || \
		#     { [ "$zip" ] && fn=$(zipinfo -1 -- "${FILE_PATH}"); } || return
		#
		#     fn=$(echo "$fn" | python -c "import sys; import mimetypes as m; \
		#             [ print(l, end='') for l in sys.stdin if \
		#               (m.guess_type(l[:-1])[0] or '').startswith('image/') ]" |\
		#         sort -V | head -n 1)
		#     [ "$fn" = "" ] && return
		#     [ "$bsd" ] && fn=$(printf '%b' "$fn")
		#
		#     [ "$tar" ] && tar --extract --to-stdout \
		#         --file "${FILE_PATH}" -- "$fn" > "${IMAGE_CACHE_PATH}" && exit 6
		#     fe=$(echo -n "$fn" | sed 's/[][*?\]/\\\0/g')
		#     [ "$bsd" ] && bsdtar --extract --to-stdout \
		#         --file "${FILE_PATH}" -- "$fe" > "${IMAGE_CACHE_PATH}" && exit 6
		#     [ "$bsd" ] || [ "$tar" ] && rm -- "${IMAGE_CACHE_PATH}"
		#     [ "$rar" ] && unrar p -p- -inul -- "${FILE_PATH}" "$fn" > \
		#         "${IMAGE_CACHE_PATH}" && exit 6
		#     [ "$zip" ] && unzip -pP "" -- "${FILE_PATH}" "$fe" > \
		#         "${IMAGE_CACHE_PATH}" && exit 6
		#     [ "$rar" ] || [ "$zip" ] && rm -- "${IMAGE_CACHE_PATH}"
		#     ;;
	esac

	# openscad_image() {
	#     TMPPNG="$(mktemp -t XXXXXX.png)"
	#     openscad --colorscheme="${OPENSCAD_COLORSCHEME}" \
	#         --imgsize="${OPENSCAD_IMGSIZE/x/,}" \
	#         -o "${TMPPNG}" "${1}"
	#     mv "${TMPPNG}" "${IMAGE_CACHE_PATH}"
	# }

	# case "${FILE_EXTENSION_LOWER}" in
	#     ## 3D models
	#     ## OpenSCAD only supports png image output, and ${IMAGE_CACHE_PATH}
	#     ## is hardcoded as jpeg. So we make a tempfile.png and just
	#     ## move/rename it to jpg. This works because image libraries are
	#     ## smart enough to handle it.
	#     csg|scad)
	#         openscad_image "${FILE_PATH}" && exit 6
	#         ;;
	#     3mf|amf|dxf|off|stl)
	#         openscad_image <(echo "import(\"${FILE_PATH}\");") && exit 6
	#         ;;
	# esac
}

handle_mime() {
	local mimetype="${1}"
	case "$mimetype" in
	## RTF and DOC
	text/rtf | *msword)
		## Preview as text conversion
		## note: catdoc does not always work for .doc files
		## catdoc: http://www.wagner.pp.ru/~vitus/software/catdoc/
		catdoc -- "$FILE_PATH" && exit 5
		exit 1
		;;

	## DOCX, ePub, FB2 (using markdown)
	## You might want to remove "|epub" and/or "|fb2" below if you have
	## uncommented other methods to preview those formats
	*wordprocessingml.document | */epub+zip | */x-fictionbook+xml)
		## Preview as markdown conversion
		pandoc -s -t markdown -- "$FILE_PATH" | mdcat && exit 5
		# pandoc -s -t markdown -- "${FILE_PATH}" | glow -s dark - && exit 5
		# pandoc -s -t markdown -- "${FILE_PATH}" && exit 5
		exit 1
		;;

	## XLS
	*ms-excel)
		## Preview as csv conversion
		## xls2csv comes with catdoc:
		##   http://www.wagner.pp.ru/~vitus/software/catdoc/
		xls2csv -- "$FILE_PATH" && exit 5
		exit 1
		;;

	## Text
	text/* | */xml)
		## Syntax highlight
		if [[ "$(stat --printf='%s' -- "$FILE_PATH")" -gt "$HIGHLIGHT_SIZE_MAX" ]]; then
			exit 2
		fi
		if [[ "$(tput colors)" -ge 256 ]]; then
			local pygmentize_format='terminal256'
			local highlight_format='xterm256'
		else
			local pygmentize_format='terminal'
			local highlight_format='ansi'
		fi
		env HIGHLIGHT_OPTIONS="$HIGHLIGHT_OPTIONS" highlight \
			--out-format="$highlight_format" \
			--force -- "$FILE_PATH" && exit 5
		env COLORTERM=8bit bat --color=always --style="numbers" \
			-- "$FILE_PATH" && exit 5
		# env COLORTERM=8bit bat --color=always --style="numbers" \
		#     --theme=base16 -- "${FILE_PATH}" && exit 5
		pygmentize -f "$pygmentize_format" -O "style=${PYGMENTIZE_STYLE}" \
			-- "$FILE_PATH" && exit 5
		exit 2
		;;

	## DjVu
	image/vnd.djvu)
		## Preview as text conversion (requires djvulibre)
		djvutxt "$FILE_PATH" | fmt -w "$PV_WIDTH" && exit 5
		exiftool "$FILE_PATH" && exit 5
		exit 1
		;;

	## Image
	image/*)
		## Preview as text conversion
		# img2txt --gamma=0.6 --width="${PV_WIDTH}" -- "${FILE_PATH}" && exit 4
		exiftool "$FILE_PATH" && exit 5
		exit 1
		;;

	## Video and audio
	video/* | audio/*)
		mediainfo "$FILE_PATH" && exit 5
		exiftool "$FILE_PATH" && exit 5
		exit 1
		;;
	esac
}

handle_fallback() {
	echo '----- File Type Classification -----' && file --dereference --brief -- "$FILE_PATH" && exit 5
	exit 1
}

MIMETYPE="$(file --dereference --brief --mime-type -- "$FILE_PATH")"
if [[ "$PV_IMAGE_ENABLED" == 'True' ]]; then
	handle_image "$MIMETYPE"
fi
handle_extension
handle_mime "$MIMETYPE"
handle_fallback

exit 1
