Update torrents with current tracker URL via transmission-remote (uses a gsed alias)

replace_tracker.sh

#!/bin/bash
SECONDS=0
CMD=/usr/local/bin/transmission-remote
TR=$(/usr/local/bin/transmission-remote)

# Your announce key for the new tracker (keep secret)
KEY="key"
# Transmission daemon host
HOST="localhost:9091"
# Authentication to transmission-daemon; 1 = True, 0 = False
AUTH=1
TDUSER="user"
TDPASS="passwd"
# Old tracker URL to be replaced
OLD="old"
# New tracker URL
NEW="new"

displaytime () {
   local T=$SECONDS
   local D=$((T/60/60/24))
   local H=$((T/60/60%24))
   local M=$((T/60%60))
   local S=$((T%60))
   [[ $D > 0 ]] && printf '%d days ' $D
   [[ $H > 0 ]] && printf '%d hours ' $H
   [[ $M > 0 ]] && printf '%d minutes ' $M
   [[ $D > 0 || $H > 0 || $M > 0 ]] && printf 'and '
   printf '%d seconds\n' $S
}

# Check $PATH for command
if ! [ -x "$(command -v transmission-remote)" ]; then
    echo -e 'Error: transmission-remote is not on your $PATH or is not installed.\n' >&2
    exit 1
fi

# Check if command exists.
if [[ -f $CMD ]] ; then
    echo -e "The command transmission-remote was found, Proceeding...\n"
    else
        echo -e "The command transmission-remote was not found at $TR. Please edit \$TR or install transmission-remote. Exiting.\n"
        exit 2
fi

if [ ${AUTH} -eq 1 ]; then
    OPTS="${HOST} -n ${TDUSER}:${TDPASS}"
        else
	OPTS="${HOST}"
fi

# Get all torrent IDs
LISTID=$(${TR} ${OPTS} -l | awk '{print $1}' | grep -E '^[0-9]+' | gsed -r -e 's/^([0-9]*).*$/\1/') 
COUNT=$(echo ${LISTID} | wc -l)
echo -e "Found $COUNT torrents for $HOST\n"

for id in ${LISTID}; do
    echo "================================"
# Get all trackers
    TRACKS=$(${TR} ${OPTS} -t ${id} -it | grep -E 'Tracker [0-9]+')
# Check for old tracker
    TRTEST=$(echo "${TRACKS}" | grep '${OLD}')
    if [ $? -eq 0 ]; then
        echo "Found old tracker - ${OLD} on torrent ID ${id} ..."
# Get tracker ID
	TRKID=$(echo "${TRACKS}" | grep "${OLD}" | gsed -r -e 's/Tracker ([0-9]+).*/\1/') 
        echo $TRKID
        echo "Removing ${OLD} tracker from transmission client..."
	${TR} ${OPTS} -t ${id} -tr ${TRKID}
        echo "Adding new tracker ${NEW} to torrent ${id} ..."
	${TR} ${OPTS} -t ${id} -td "${NEW}/${KEY}/announce"
    fi
done

TIME=$(displaytime)
echo -e "Completed in $TIME.\n"

exit 0