#!/usr/bin/env bash
# Both standalone script and qutebrowser userscript that opens a rofi menu with
# all files from the download directory and opens the selected file. It works
# both as a userscript and a standalone script that is called from outside of
# qutebrowser.
#
# Suggested keybinding (for "show downloads"):
# spawn --userscript ~/.config/qutebrowser/open_download
#     sd
#
# Requirements:
#  - rofi (in a recent version)
#  - xdg-open and xdg-mime
#  - You should configure qutebrowser to download files to a single directory
#  - It comes in handy if you enable downloads.remove_finished. If you want to
#    see the recent downloads, just press "sd".
#
# Thorsten Wißmann, 2015 (thorsten` on freenode)
# Any feedback is welcome!

set -e

# open a file from the download directory using rofi
DOWNLOAD_DIR=${DOWNLOAD_DIR:-$QUTE_DOWNLOAD_DIR}
DOWNLOAD_DIR=${DOWNLOAD_DIR:-$HOME/Downloads}
# the name of the rofi command
ROFI_CMD=${ROFI_CMD:-rofi}
ROFI_ARGS=${ROFI_ARGS:-}

msg() {
    local cmd="$1"
    shift
    local msg="$*"
    if [ -z "$QUTE_FIFO" ] ; then
        echo "$cmd: $msg" >&2
    else
        echo "message-$cmd '${msg//\'/\\\'}'" >> "$QUTE_FIFO"
    fi
}
die() {
    msg error "$*"
    if [ -n "$QUTE_FIFO" ] ; then
        # when run as a userscript, the above error message already informs the
        # user about the failure, and no additional "userscript exited with status
        # 1" is needed.
        exit 0;
    else
        exit 1;
    fi
}

if ! [ -d "$DOWNLOAD_DIR" ] ; then
    die "Download directory »$DOWNLOAD_DIR« not found!"
fi
if ! command -v "${ROFI_CMD}" > /dev/null ; then
    die "Rofi command »${ROFI_CMD}« not found in PATH!"
fi

rofi_default_args=(
        -monitor -2 # place above window
        -location 6 # aligned at the bottom
        -i
        -no-custom
        -format i   # make rofi return the index
        -l 10
        -p 'Open download' -dmenu
    )

crop-first-column() {
    local maxlength=${1:-40}
    local expression='s|^\([^\t]\{0,'"$maxlength"'\}\)[^\t]*\t|\1\t|'
    sed "$expression"
}

ls-files() {
    # add the slash at the end of the download dir enforces to follow the
    # symlink, if the DOWNLOAD_DIR itself is a symlink
    # shellcheck disable=SC2010
    ls -Q --quoting-style escape    -h  -o -1 -A -t "${DOWNLOAD_DIR}/" \
        | grep '^[-]' \
        | cut -d' ' -f3- \
        | sed 's,^\(.*[^\]\) \(.*\)$,\2\t\1,' \
        | sed 's,\\\(.\),\1,g'
}

mapfile -t entries < <(ls-files)

# we need to manually check that there are items, because rofi doesn't show up
# if there are no items and -no-custom is passed to rofi.
if [ "${#entries[@]}" -eq 0 ] ; then
    die "Download directory »${DOWNLOAD_DIR}« empty"
fi

line=$(printf '%s\n' "${entries[@]}"  \
       | crop-first-column 55 \
       | column -s $'\t' -t \
       | $ROFI_CMD "${rofi_default_args[@]}" "$ROFI_ARGS") || true
if [ -z "$line" ];  then
    exit 0
fi

file="${entries[$line]}"
file="${file%%$'\t'*}"
path="$DOWNLOAD_DIR/$file"
filetype=$(xdg-mime query filetype "$path")
application=$(xdg-mime query default "$filetype")

if [ -z "$application" ] ; then
    die "Do not know how to open »$file« of type $filetype"
fi

msg info "Opening »$file« (of type $filetype) with ${application%.desktop}"

xdg-open "$path" &