#!/bin/bash

# Set mode
if [ "$1" = "auto" ]; then
    mode="auto"
else
    mode="man"
fi

# Read environment variables
source "${HOME}/.borg-env"

# some helpers and error handling:
info() {
    printf "\n%s %s\n\n" ${DATE} "$*" >&2;
    echo "$( date ) BORGBACKUP $* " >> /var/log/backup.log;
}

# function to send ntfy messages
ntfy() {
    local message="$1"
    local priority="$2"
    local ntfy_url="${NTFY_URL}"
    local ntfy_token="${NTFY_TOKEN}"

    if [ -z "${ntfy_url}" ]; then
        info "NTFY_URL is not set. Cannot send notification."
        return
    fi

    # construct curl command with or without token
    if [ -z "${ntfy_token}" ]; then
        local curl_command="curl -H 'Priority: ${priority}' -d '${message}' '${ntfy_url}'"
    else
        local curl_command="curl -H 'Authorization: Bearer ${ntfy_token}' -H 'Priority: ${priority}' -d '${message}' '${ntfy_url}'"
    fi

    # send curl and log result
    if eval "${curl_command}"; then
        info "Notification sent successfully: ${message}"
    else
        info "Failed to send notification: ${message}"
    fi
}

trap 'echo $( date ) Backup interrupted >&2; exit 2' INT TERM

info "Starting backup"

exclude() {
    for entry in "${BORG_EXCLUDE[@]}"; do
        echo "--exclude $entry"
    done
}

# Backup the most important directories into an archive named after
# the machine this script is currently running on:

borg_command=("/usr/local/bin/borg create" "--verbose" "--filter AME" "--list" "--stats" "--show-rc" "--compression lz4" "--exclude-caches")
borg_command+=($(exclude))
borg_command+=("::backup-{hostname}-{now}" "${BORG_TARGETS[@]}")

"${borg_command[@]}"

backup_exit=$?

if [ $mode = "auto" ]; then

    info "Pruning repository"

    # Use the `prune` subcommand to maintain 7 daily, 4 weekly and 6 monthly
    # archives of THIS machine. The '{hostname}-' prefix is very important to
    # limit prune's operation to this machine's archives and not apply to
    # other machines' archives also:

    /usr/local/bin/borg prune           \
        --list                          \
        --glob-archives 'auto-*'        \
        --show-rc                       \
        --keep-daily    7               \
        --keep-weekly   4               \
        --keep-monthly  6               \
        --keep-yearly   2               \

    prune_exit=$?

    # actually free repo disk space by compacting segments

    info "Compacting repository"

    /usr/local/bin/borg compact

    compact_exit=$?

    # use highest exit code as global exit code
    global_exit=$(( backup_exit > prune_exit ? backup_exit : prune_exit ))
    global_exit=$(( compact_exit > global_exit ? compact_exit : global_exit ))

else
    global_exit=$(( compact_exit > global_exit ? compact_exit : global_exit ))
fi

if [ ${global_exit} -eq 0 ]; then
    info "Borg Backups finished successfully"
    if [ "${NTFY}" = "true" ]; then
        ntfy "${HOSTNAME}: Borg Backups finished successfully" "low"
    fi
elif [ ${global_exit} -eq 1 ]; then
    info "Borg Backups finished with warnings"
    if [ "${NTFY}" = "true" ]; then
        ntfy "${HOSTNAME}: Borg Backups finished with warnings" "urgent"
    fi
else
    info "Borg Backups finished with errors"
    if [ "${NTFY}" = "true" ]; then
        ntfy "${HOSTNAME}: Borg Backups finished with errors" "urgent"
    fi
fi
exit ${global_exit}