#!/usr/bin/env bash

set -u

declare -r username='transmission'
declare -r password='transmission'
declare -r download_dir='/var/lib/transmission-daemon/downloads'

declare -t log='/var/log/transmission-purge.log'


log()
{
    local timestamp="$(/bin/date +'%Y-%m-%dT%H:%M:%S%z')"
    local level="$1"
    shift 1
    printf "%s - %s - %b\n" "$timestamp" "$level" "$@" | \
        /usr/bin/tee -a "$log" >&2
}

log_info()
{
    log 'INFO' "$@"
}

log_error()
{
    log 'ERROR' "$@"
}

die()
{
    log 'ERROR' "$@"
    exit 1
}

log_info '----------------------------------------'

trap 'log_info "----------------------------------------"' \
     HUP INT TERM EXIT

if [ ! -d "$download_dir" ]; then
    die "Transmission download directory '$download_dir' not found"
fi

log_info "List tasks"

output="$(transmission-remote -n "$username":"$password" -l)"
status=$?

log_info "Tasks\n$output"

if [ $status -ne 0 ]; then
    die "Failed to list tasks, status: $status"
fi

log_info "Check orphan files"

/bin/ls -1 "$download_dir" | \
    while IFS='' read -r line || [[ -n "$line" ]]; do
        case $output in
            *"$line"*) ;;
            *) log_info "Orphan: ${download_dir}/${line}" ;;
        esac
    done

log_info "Free Spaces\n$(df -h /)"