#!/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
        ;;

    ## 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
    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}" && 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 -- "${FILE_PATH}" && exit 5
        env COLORTERM=8bit bat --color=always --style="plain" \
            -- "${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
