#!/bin/sh
set -eu

viewer=

notify() {
  if [ -x /usr/bin/notify-send ]; then
    /usr/bin/notify-send "SimpleImageViewer" "$1" || true
  fi
}

types=$(/usr/bin/wl-paste --list-types 2>/dev/null || true)

text_type=$(
  printf '%s\n' "$types" | /usr/bin/awk '
        /^text\/plain/ || $0 == "text/uri-list" || $0 == "UTF8_STRING" || $0 == "STRING" {
            print
            exit
        }
    '
)

path=
if [ -n "$text_type" ]; then
  path=$(
    /usr/bin/wl-paste --no-newline --type "$text_type" 2>/dev/null | /usr/bin/awk '
            {
                sub(/^[[:space:]]+/, "")
                sub(/[[:space:]]+$/, "")
                if ($0 == "" || $0 == "copy" || $0 == "cut" || substr($0, 1, 1) == "#") next
                sub(/^file:\/\//, "")
                gsub(/%20/, " ")
                sub(/^~/, ENVIRON["HOME"])
                print
                exit
            }
        '
  )
fi

if [ -n "$path" ] && [ -f "$path" ]; then
  exec "$viewer" "$path"
fi

image_type=$(
  printf '%s\n' "$types" | /usr/bin/awk '
        $0 == "image/png" { found = $0; print; exit }
        $0 == "image/jpeg" || $0 == "image/jpg" { found = $0; print; exit }
        $0 == "image/bmp" || $0 == "image/x-bmp" { found = $0; print; exit }
        $0 == "image/gif" { found = $0; print; exit }
        $0 == "image/x-tga" || $0 == "image/tga" { found = $0; print; exit }
        $0 == "image/x-portable-pixmap" || $0 == "image/x-portable-anymap" { found = $0; print; exit }
        /^image\// && fallback == "" { fallback = $0 }
        END { if (found == "" && fallback != "") print fallback }
    '
)

if [ -z "$image_type" ]; then
  notify "Clipboard contains neither an image path nor image data"
  exit 1
fi

case "$image_type" in
image/png) ext=png ;;
image/jpeg | image/jpg) ext=jpg ;;
image/bmp | image/x-bmp) ext=bmp ;;
image/gif) ext=gif ;;
image/x-tga | image/tga) ext=tga ;;
image/x-portable-pixmap) ext=ppm ;;
image/x-portable-anymap) ext=pnm ;;
*) ext=img ;;
esac

tmpdir=$(/usr/bin/mktemp -d "${TMPDIR:-/tmp}/simple-image-viewer.XXXXXXXXXX")

cleanup() {
  /usr/bin/rm -rf "$tmpdir"
}

trap cleanup EXIT
trap 'exit 130' HUP INT TERM

image_path=$tmpdir/clipboard.$ext
if ! /usr/bin/wl-paste --type "$image_type" >"$image_path"; then
  notify "Could not read image data from clipboard"
  exit 1
fi

if [ ! -s "$image_path" ]; then
  notify "Clipboard image data is empty"
  exit 1
fi

"$viewer" "$image_path"