torrpen - automated torrent management by size

torrpen

#!/bin/bash

rtorrent_watch_dir=~/torrent
torrent_holding_pen=~/torrent/pending
buffer=$((600 * 1024)) # Size in KB to keep unused (600MB)

space_left=$(($(df $rtorrent_watch_dir | awk '/dev/ {print $4}') - $buffer))
tmpdir=$(mktemp -d /tmp/torrpen.XXXX)

get_torrent_size () {
    size=$(echo "$(transmissioncli --info "$1" |& awk '/size/ {print $2}') / 1024" | bc)
    echo $size
}

cleanup () {
    rm -rf "$tmpdir"
    exit
}

cd "$torrent_holding_pen"
declare -A torrent_sizes
for torrent in *.torrent; do
    [[ -f "$torrent" ]] || exit # Dir is empty
    torrsize=$(get_torrent_size "$torrent")
    torrent_sizes["$torrent"]=$torrsize
done

for key in "${!torrent_sizes[@]}"; do
    echo "${torrent_sizes[$key]} $key"
done | sort -n > "$tmpdir/sizes"

projected_space=$space_left
while read size torrent < "$tmpdir/sizes"; do
    (( projected_space > 0 )) || break
    if (( size < projected_space )); then
        mv "$torrent" "$rtorrent_watch_dir"
        let "projected_space -= size"
    else
        break
    fi
done

cleanup