#!/bin/bash
# shellcheck disable=SC2016

# send .desktop files from directories persisting across VM restarts, specifically:
#  - any directory in case of "full" persistence
#  - directories stored on /rw in case of "rw-only" persistence
#  - nothing, otherwise

# Reload scripts in /etc/profile.d/, in case they register additional
# directories in XDG_DATA_DIRS and we forgot them
# (e.g. because we are running under sudo).
# shellcheck disable=SC1091
source /etc/profile

if [ -z "$XDG_DATA_HOME" ]; then
    user="$(whoami)"
    # In case we are running under sudo, use default-user.
    if [ "$user" = "root" ]; then
        user="$(qubesdb-read /default-user || echo user)"
    fi
    home="$(eval echo "~$user")"
    XDG_DATA_HOME="$home/.local/share"
fi
if [ -z "$XDG_DATA_DIRS" ]; then
    XDG_DATA_DIRS="/usr/local/share/:/usr/share/"
fi

# if read fails for some reason, default to full
persistence=$(qubesdb-read /qubes-vm-persistence || echo full)
rw_devno=$(stat -c %D /rw)

apps_dirs_to_consider=( "$XDG_DATA_HOME" )
old_IFS="$IFS"
IFS=:
# shellcheck disable=SC2206
apps_dirs_to_consider+=( $XDG_DATA_DIRS )
IFS="$old_IFS"

apps_dirs=()
for dir in "${apps_dirs_to_consider[@]}"; do
    if [ "$persistence" = "full" ]; then
        apps_dirs+=( "$dir/applications" )
    elif [ "$persistence" = "rw-only" ] && \
            [ "$(stat -c %D "$dir")" = "$rw_devno" ]; then
        apps_dirs+=( "$dir/applications" )
    fi
done

if [ "${#apps_dirs[@]}" -eq "0" ]; then
    # nothing to send, exit early to not let `find` browse the current
    # directory
    exit 0
fi

find "${apps_dirs[@]}" -name '*.desktop' -print0 2>/dev/null | \
         xargs -0 awk '
         BEGINFILE { if (ERRNO) nextfile; entry="" }
         /^\[/ { if (tolower($0) != "\[desktop entry\]") nextfile } 
         /^Exec *=/ { entry = entry FILENAME ":Exec=qubes-desktop-run " FILENAME "\n"; next }
         /^NoDisplay *= *true$/ { entry=""; nextfile }
         /=/ { entry = entry FILENAME ":" $0 "\n" }
         ENDFILE { print entry }
         ' 2> /dev/null