#!/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.

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

# Settings
HIGHLIGHT_SIZE_MAX=262143 # 256KiB

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
            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
            ;; # Continue with next handler on failure
    esac
}

handle_image() {
    local mimetype="${1}"
    case "${mimetype}" in
        # SVG
        # image/svg+xml)
        #     convert "${FILE_PATH}" "${IMAGE_CACHE_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 1920 \
            #              -scale-to-y -1 \
            #              -singlefile \
            #              -jpeg -tiffcompression jpeg \
            #              -- "${FILE_PATH}" "${IMAGE_CACHE_PATH%.*}" \
            #         && exit 6 || exit 1 ;;
    esac
}

handle_mime() {
    local mimetype="${1}"
    case "${mimetype}" in
        # Text
        text/* | */xml)
            # Syntax highlight
            if [[ "$(stat --printf='%s' -- "${FILE_PATH}")" -gt "${HIGHLIGHT_SIZE_MAX}" ]]; then
                exit 2
            fi
            export COLORTERM=tmux-256color
            bat --line-range :200 "${FILE_PATH}" && exit 5
            exit 2
            ;;

            # 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
