#!/bin/sh
# Run the backup and mail the logs
# Set TEST_SMTP=1 to run in SMTP testing mode, which will just send an email

set -o pipefail

# Set up environment
/bin/sh /scripts/msmtprc.sh
/bin/sh /scripts/env.sh
BACKUP_COMMAND="borgmatic --stats -v 2"
LOGFILE="/tmp/backup_run_$(date +%s).log"
SUCCESS_PREFIX="=?utf-8?Q? =E2=9C=85 SUCCESS?="
FAILED_PREFIX="=?utf-8?Q? =E2=9D=8C FAILED?="

# Helper function to prepend a timestamp and the first parameter to every line of STDIN
_indent() {
    while read -rs line; do
	printf "%s%s\n" "$(date +%s)" "$1" "$line"
    done
}

# This function prepends timestamps to stderr and stdout of the
# command supplied as parameters to this.
log() {
    # Adapted from https://stackoverflow.com/a/31151808
    {
	"$@"   2>&1 1>&3 3>&- | _indent " ! "
    } 3>&1 1>&2 | _indent " | " >>"$LOGFILE"
}

report() {
    if [ -n "$SUCCESS" ]; then
	log echo SUCCESS
        PREFIX="$SUCCESS_PREFIX"
    else
	log echo FAILED
        PREFIX="$FAILED_PREFIX"
    fi
    printf "Subject: $PREFIX: $MAIL_SUBJECT\n\n$(cat $LOGFILE)\n" |
        sendmail -t "$MAIL_TO"
}

testmail() {
    echo -e "Subject: TESTING!\n\ntest mail, please ignore\n" |
        sendmail -t "$MAIL_TO"
}

failed() {
    log echo "Exited abnormally!"
    report
    rm -f "$LOGFILE"
}

cleanup() {
    borgmatic break-lock
    echo "Done, removing $LOGFILE"
    rm -f "$LOGFILE"
}

# Handle various kinds of exit
trap failed INT QUIT KILL
trap cleanup EXIT

if [ -n "$TEST_SMTP" ]; then
    echo "Testing mail to $MAIL_TO"
    testmail
    echo "Done."
    exit
fi


echo "STARTED" >> "$LOGFILE"
if log $BACKUP_COMMAND; then
    SUCCESS=1
    report
fi