#!/usr/bin/env bash
set -eou pipefail

# Get the list of rooms with no local users
empty_rooms() {
    psql -d synapse -c "SELECT room_id FROM room_stats_current WHERE local_users_in_room = 0 \
        ORDER BY current_state_events DESC LIMIT 1;" -t --csv
}

# Delete a room and purge its history
delete_room() {
    details=$(synadm room details $1)
    name=$(echo $details | jq -r '.name')
    canonical_alias=$(echo $details | jq -r '.canonical_aliacanonical_alias')
    topic=$(echo $details | jq -r '.topic')
    joined_local_members=$(echo $details | jq -r '.joined_local_members')
    state_events=$(echo $details | jq -r '.state_events')
    echo "Deleting room $1 (name: $name, canonical alias: $canonical_alias, topic: $topic)[$joined_local_members]"
    echo "This will remove $state_events state events"
    if [[ $joined_local_members == "0" ]];
    then
        time synadm --yes room delete $1
    else
        echo "Room still had active members!!! $1"
    fi
    echo ""
}

log_file="empty-removal-$(date -Iminutes).log"
touch $log_file
for room in $(empty_rooms); do
    delete_room $room | tee -a $log_file
done