#!/command/with-contenv bash

bootstrap_compression() {
    ### Set Compression Options
    if var_true "${ENABLE_PARALLEL_COMPRESSION}" ; then
        bzip="pbzip2 -${COMPRESSION_LEVEL}"
        gzip="pigz -${COMPRESSION_LEVEL}"
        xzip="pixz -${COMPRESSION_LEVEL}"
        zstd="zstd --rm -${COMPRESSION_LEVEL}"
    else
        bzip="bzip2 -${COMPRESSION_LEVEL}"
        gzip="gzip -${COMPRESSION_LEVEL}"
        xzip="xz -${COMPRESSION_LEVEL} "
        zstd="zstd --rm -${COMPRESSION_LEVEL}"
    fi
}

bootstrap_variables() {
    case "${dbtype,,}" in
        couch* )
            dbtype=couch
            dbport=${DB_PORT:-5984}
            file_env 'DB_USER'
            file_env 'DB_PASS'
        ;;
        influx* )
            dbtype=influx
            dbport=${DB_PORT:-8088}
            file_env 'DB_USER'
            file_env 'DB_PASS'
        ;;
        mongo* )
            dbtype=mongo
            dbport=${DB_PORT:-27017}
            [[ ( -n "${DB_USER}" ) || ( -n "${DB_USER_FILE}" ) ]] && file_env 'DB_USER'
            [[ ( -n "${DB_PASS}" ) || ( -n "${DB_PASS_FILE}" ) ]] && file_env 'DB_PASS'
        ;;
        "mysql" | "mariadb" )
            dbtype=mysql
            dbport=${DB_PORT:-3306}
            [[ ( -n "${DB_PASS}" ) || ( -n "${DB_PASS_FILE}" ) ]] && file_env 'DB_PASS'
        ;;
        "mssql" | "microsoftsql" )
            apkArch="$(apk --print-arch)"; \
            case "$apkArch" in
                x86_64) mssql=true ;;
                *) print_error "MSSQL cannot operate on $apkArch processor!" ; exit 1 ;;
            esac
            dbtype=mssql
            dbport=${DB_PORT:-1433}
        ;;
        postgres* | "pgsql" )
            dbtype=pgsql
            dbport=${DB_PORT:-5432}
            [[ ( -n "${DB_PASS}" ) || ( -n "${DB_PASS_FILE}" ) ]] && file_env 'DB_PASS'
        ;;
        "redis" )
            dbtype=redis
            dbport=${DB_PORT:-6379}
            [[ ( -n "${DB_PASS}" || ( -n "${DB_PASS_FILE}" ) ) ]] && file_env 'DB_PASS'
        ;;
        sqlite* )
            dbtype=sqlite3
        ;;
    esac

    if [ "${BACKUP_LOCATION,,}" = "s3" ] || [ "${BACKUP_LOCATION,,}" = "minio" ] ; then
        file_env 'S3_KEY_ID'
        file_env 'S3_KEY_SECRET'
    fi

    ### Set the Database Authentication Details
    case "$dbtype" in
        "mongo" )
            [[ ( -n "${DB_USER}" ) ]] && MONGO_USER_STR=" --username ${dbuser}"
            [[ ( -n "${DB_PASS}" ) ]] && MONGO_PASS_STR=" --password ${dbpass}"
            [[ ( -n "${DB_NAME}" ) ]] && MONGO_DB_STR=" --db ${dbname}"
            [[ ( -n "${DB_AUTH}" ) ]] && MONGO_AUTH_STR=" --authenticationDatabase ${DB_AUTH}"
        ;;
        "mysql" )
            [[ ( -n "${DB_PASS}" ) ]] && export MYSQL_PWD=${dbpass}
        ;;
        "postgres" )
            [[ ( -n "${DB_PASS}" ) ]] && POSTGRES_PASS_STR="PGPASSWORD=${dbpass}"
        ;;
        "redis" )
            [[ ( -n "${DB_PASS}" ) ]] && REDIS_PASS_STR=" -a ${dbpass}"
        ;;
    esac
}

backup_couch() {
    target=couch_${dbname}_${dbhost}_${now}.txt
    compression
    print_notice "Dumping CouchDB database: '${dbname}'"
    curl -X GET http://${dbhost}:${dbport}/${dbname}/_all_docs?include_docs=true ${dumpoutput} | $dumpoutput > ${TEMP_LOCATION}/${target}
    exit_code=$?
    check_exit_code
    generate_checksum
    move_backup
}

backup_influx() {
    if [ "${ENABLE_COMPRESSION,,}" = "none" ] || [ "${ENABLE_COMPRESSION,,}" = "false" ] ; then
        :
    else
        print_notice "Compressing InfluxDB backup with gzip"
        influx_compression="-portable"
    fi
    for DB in ${DB_NAME}; do
        print_notice "Dumping Influx database: '${DB}'"
        target=influx_${DB}_${dbhost}_${now}
        influxd backup ${influx_compression} -database $DB -host ${dbhost}:${dbport} ${TEMP_LOCATION}/${target}
        exit_code=$?
        check_exit_code
        generate_checksum
        move_backup
    done
}

backup_mongo() {
    if [ "${ENABLE_COMPRESSION,,}" = "none" ] || [ "${ENABLE_COMPRESSION,,}" = "false" ] ; then
        target=${dbtype}_${dbname}_${dbhost}_${now}.archive
    else
        print_notice "Compressing MongoDB backup with gzip"
        target=${dbtype}_${dbname}_${dbhost}_${now}.archive.gz
        mongo_compression="--gzip"
    fi
    print_notice "Dumping MongoDB database: '${DB_NAME}'"
    mongodump --archive=${TEMP_LOCATION}/${target} ${mongo_compression} --host ${dbhost} --port ${dbport} ${MONGO_USER_STR}${MONGO_PASS_STR}${MONGO_AUTH_STR}${MONGO_DB_STR} ${EXTRA_OPTS}
    exit_code=$?
    check_exit_code
    cd "${TEMP_LOCATION}"
    generate_checksum
    move_backup
}

backup_mssql() {
    target=mssql_${dbname}_${dbhost}_${now}.bak
    print_notice "Dumping MSSQL database: '${dbname}'"
    /opt/mssql-tools/bin/sqlcmd -E -C -S ${dbhost}\,${dbport} -U ${dbuser} -P ${dbpass} –Q "BACKUP DATABASE \[${dbname}\] TO DISK = N'${TEMP_LOCATION}/${target}' WITH NOFORMAT, NOINIT, NAME = '${dbname}-full', SKIP, NOREWIND, NOUNLOAD, STATS = 10"
    exit_code=$?
    check_exit_code
    generate_checksum
    move_backup
}

backup_mysql() {
    if var_true "${MYSQL_SINGLE_TRANSACTION}" ; then
        single_transaction="--single-transaction"
    fi
    if var_true "${MYSQL_STORED_PROCEDURES}" ; then
        stored_procedures="--routines"
    fi
    if var_true "${SPLIT_DB}" ; then
        DATABASES=$(mysql -h ${dbhost} -P $dbport -u$dbuser --batch -e "SHOW DATABASES;" | grep -v Database | grep -v schema)
        for db in "${DATABASES}" ; do
                if [[ "$db" != "information_schema" ]] && [[ "$db" != _* ]] ; then
                    print_debug "Backing up everything except for information_schema and _* prefixes"
                    print_notice "Dumping MySQL/MariaDB database: '${db}'"
                    target=mysql_${db}_${dbhost}_${now}.sql
                    compression
                    mysqldump --max-allowed-packet=${MYSQL_MAX_ALLOWED_PACKET} -h $dbhost -P $dbport -u$dbuser ${single_transaction} ${stored_procedures} ${EXTRA_OPTS} --databases $db | $dumpoutput > ${TEMP_LOCATION}/${target}
                    exit_code=$?
                    check_exit_code
                    generate_checksum
                    move_backup
                fi
        done
    else
        compression
        print_notice "Dumping MySQL/MariaDB database: '${DB_NAME}'"
        mysqldump --max-allowed-packet=${MYSQL_MAX_ALLOWED_PACKET} -A -h $dbhost -P $dbport -u$dbuser  ${single_transaction} ${stored_procedures} ${EXTRA_OPTS} | $dumpoutput > ${TEMP_LOCATION}/${target}
        exit_code=$?
        check_exit_code
        generate_checksum
        move_backup
    fi
}

backup_pgsql() {
  export PGPASSWORD=${dbpass}
  if var_true "${SPLIT_DB}" ; then

      authdb=${DB_USER}
      [ -n "${DB_NAME}" ] && authdb=${DB_NAME}
      DATABASES=$(psql -h $dbhost -U $dbuser -p ${dbport} -d ${authdb} -c 'COPY (SELECT datname FROM pg_database WHERE datistemplate = false) TO STDOUT;' )
            for db in "${DATABASES}"; do
                print_notice "Dumping Postgresql database: $db"
                target=pgsql_${db}_${dbhost}_${now}.sql
                compression
                pg_dump -h ${dbhost} -p ${dbport} -U ${dbuser} $db ${EXTRA_OPTS} | $dumpoutput > ${TEMP_LOCATION}/${target}
                exit_code=$?
                check_exit_code
                generate_checksum
                move_backup
            done
  else
      compression
      print_notice "Dumping PostgreSQL: '${DB_NAME}'"
      pg_dump -h ${dbhost} -U ${dbuser} -p ${dbport} ${dbname} ${EXTRA_OPTS} | $dumpoutput > ${TEMP_LOCATION}/${target}
      exit_code=$?
      check_exit_code
      generate_checksum
      move_backup
  fi
}

backup_redis() {
    target=redis_${db}_${dbhost}_${now}.rdb
    echo bgsave | redis-cli -h ${dbhost} -p ${dbport} ${REDIS_PASS_STR} --rdb ${TEMP_LOCATION}/${target} ${EXTRA_OPTS}
    print_notice "Dumping Redis - Flushing Redis Cache First"
    sleep 10
    try=5
    while [ $try -gt 0 ] ; do
        saved=$(echo 'info Persistence' | redis-cli -h ${dbhost} -p ${dbport} ${REDIS_PASS_STR} | awk '/rdb_bgsave_in_progress:0/{print "saved"}')
        ok=$(echo 'info Persistence' | redis-cli -h ${dbhost} -p ${dbport} ${REDIS_PASS_STR} | awk '/rdb_last_bgsave_status:ok/{print "ok"}')
        if [[ "$saved" = "saved" ]] && [[ "$ok" = "ok" ]]; then
            print_notice "Redis Backup Complete"
            break
        fi
        try=$((try - 1))
        print_warn "Redis Busy - Waiting and retrying in 5 seconds"
        sleep 5
    done
    target_original=${target}
    compression
    $dumpoutput "${TEMP_LOCATION}/${target_original}"
    generate_checksum
    move_backup
}

backup_sqlite3() {
    db=$(basename "$dbhost")
    db="${db%.*}"
    target=sqlite3_${db}_${now}.sqlite3
    compression

    print_notice "Dumping sqlite3 database: '${dbhost}'"
    sqlite3 "${dbhost}" ".backup '${TEMP_LOCATION}/backup.sqlite3'"
    exit_code=$?
    check_exit_code
    cat "${TEMP_LOCATION}"/backup.sqlite3 | $dumpoutput > "${TEMP_LOCATION}/${target}"
    generate_checksum
    move_backup
}

check_availability() {
### Set the Database Type
   case "$dbtype" in
        "couch" )
            COUNTER=0
            while ! (nc -z ${dbhost} ${dbport}) ; do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "CouchDB Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "influx" )
            COUNTER=0
            while ! (nc -z ${dbhost} ${dbport}) ; do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "InfluxDB Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "mongo" )
            COUNTER=0
            while ! (nc -z ${dbhost} ${dbport}) ; do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "Mongo Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "mysql" )
            COUNTER=0
            export MYSQL_PWD=${dbpass}
            while ! (mysqladmin -u"${dbuser}" -P"${dbport}" -h"${dbhost}" status > /dev/null 2>&1) ; do
              sleep 5
              (( COUNTER+=5 ))
              print_warn "MySQL/MariaDB Server '${dbhost}' is not accessible, retrying.. (${COUNTER} seconds so far)"
            done
        ;;
        "mssql" )
            COUNTER=0
            while ! (nc -z ${dbhost} ${dbport}) ; do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "MSSQL Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "pgsql" )
            COUNTER=0
            export PGPASSWORD=${dbpass}
            until pg_isready --dbname=${dbname} --host=${dbhost} --port=${dbport} --username=${dbuser} -q
            do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "Postgres Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "redis" )
            COUNTER=0
            while ! (nc -z "${dbhost}" "${dbport}") ; do
                sleep 5
                (( COUNTER+=5 ))
                print_warn "Redis Host '${dbhost}' is not accessible, retrying.. ($COUNTER seconds so far)"
            done
        ;;
        "sqlite3" )
            if [[ ! -e "${dbhost}" ]]; then
                print_error "File '${dbhost}' does not exist."
                exit_code=2
                exit $exit_code
            elif [[ ! -f "${dbhost}" ]]; then
                print_error "File '${dbhost}' is not a file."
                exit_code=2
                exit $exit_code
            elif [[ ! -r "${dbhost}" ]]; then
                print_error "File '${dbhost}' is not readable."
                exit_code=2
                exit $exit_code
            fi
        ;;
    esac
}

check_exit_code() {
    print_debug "Exit Code is ${exit_code}"
    case "${exit_code}" in
        0 )
            print_info "Backup completed successfully"
        ;;
        * )
            print_error "Backup reported errors - Aborting"
            exit 1
        ;;
    esac
}

compression() {
   case "${ENABLE_COMPRESSION,,}" in
        gz* )
            print_notice "Compressing backup with gzip"
            target=${target}.gz
            dumpoutput="$gzip "
        ;;
        bz* )
            print_notice "Compressing backup with bzip2"
            target=${target}.bz2
            dumpoutput="$bzip "
        ;;
        xz* )
            print_notice "Compressing backup with xzip"
            target=${target}.xz
            dumpoutput="$xzip "
        ;;
        zst* )
            print_notice "Compressing backup with zstd"
            target=${target}.zst
            dumpoutput="$zstd "
        ;;
        "none" | "false")
            print_notice "Not compressing backups"
            dumpoutput="cat "
        ;;
    esac
}

generate_checksum() {
    if var_true "${ENABLE_CHECKSUM}" ; then
        case "${CHECKSUM,,}" in
            "md5" )
                checksum_command="md5sum"
                checksum_extension="md5"
            ;;
            "sha1" )
                checksum_command="sha1sum"
                checksum_extension="sha1"
            ;;
        esac

        print_notice "Generating ${checksum_extension^^} for '${target}'"
        cd "${TEMP_LOCATION}"
        ${checksum_command} "${target}" > "${target}"."${checksum_extension}"
        checksum_value=$(${checksum_command} "${target}" | awk ' { print $1}')
        print_debug "${checksum_extension^^}: ${checksum_value} - ${target}"
    fi
}

move_backup() {
    case "$SIZE_VALUE" in
        "b" | "bytes" )
            SIZE_VALUE=1
        ;;
        "[kK]" | "[kK][bB]" | "kilobytes" | "[mM]" | "[mM][bB]" | "megabytes" )
            SIZE_VALUE="-h"
        ;;
        *)
            SIZE_VALUE=1
        ;;
    esac
    if [ "$SIZE_VALUE" = "1" ] ; then
        FILESIZE=$(stat -c%s "${TEMP_LOCATION}"/"${target}")
        print_notice "Backup of ${target} created with the size of ${FILESIZE} bytes"
    else
        FILESIZE=$(du -h "${TEMP_LOCATION}"/"${target}" | awk '{ print $1}')
        print_notice "Backup of ${target} created with the size of ${FILESIZE}"
    fi

    case "${BACKUP_LOCATION,,}" in
        "file" | "filesystem" )
            print_debug "Moving backup to filesystem"
            mkdir -p "${DB_DUMP_TARGET}"
            mv "${TEMP_LOCATION}"/*."${checksum_extension}" "${DB_DUMP_TARGET}"/
            mv "${TEMP_LOCATION}"/"${target}" "${DB_DUMP_TARGET}"/"${target}"
        ;;
        "s3" | "minio" )
            print_debug "Moving backup to S3 Bucket"
            export AWS_ACCESS_KEY_ID=${S3_KEY_ID}
            export AWS_SECRET_ACCESS_KEY=${S3_KEY_SECRET}
            export AWS_DEFAULT_REGION=${S3_REGION}
            if [ -f "${S3_CERT_CA_FILE}" ] ; then
                print_debug "Using Custom CA for S3 Backups"
                s3_ssl=" --ca-bundle ${S3_CERT_CA_FILE}"
            fi
            if var_true "${S3_CERT_SKIP_VERIFY}" ; then
                print_debug "Skipping SSL verification for HTTPS S3 Hosts"
                s3_ssl="${s3_ssl} --no-verify-ssl"
            fi

            [[ ( -n "${S3_HOST}" ) ]] && PARAM_AWS_ENDPOINT_URL=" --endpoint-url ${S3_PROTOCOL}://${S3_HOST}"

            aws ${PARAM_AWS_ENDPOINT_URL} s3 cp ${TEMP_LOCATION}/${target} s3://${S3_BUCKET}/${S3_PATH}/${target} ${s3_ssl} ${S3_EXTRA_OPTS}

            rm -rf "${TEMP_LOCATION}"/*."${checksum_extension}"
            rm -rf "${TEMP_LOCATION}"/"${target}"
        ;;
    esac
}

sanity_test() {
    sanity_var DB_TYPE "Database Type"
    sanity_var DB_HOST "Database Host"
    file_env 'DB_USER'
    file_env 'DB_PASS'

    if [ "${BACKUP_LOCATION,,}" = "s3" ] || [ "${BACKUP_LOCATION,,}" = "minio" ] ; then
        sanity_var S3_BUCKET "S3 Bucket"
        sanity_var S3_PATH "S3 Path"
        sanity_var S3_REGION "S3 Region"
        file_env 'S3_KEY_ID'
        file_env 'S3_KEY_SECRET'
    fi
}

setup_mode() {
    if [ "${MODE,,}" = "auto" ] || [ ${MODE,,} = "default" ] ; then
        print_debug "Running in Auto / Default Mode - Letting Image control scheduling"
    else
        print_info "Running in Manual mode - Execute 'backup_now' to run a manual backup"
        service_stop 10-db-backup
        if var_true "${MANUAL_RUN_FOREVER}" ; then
            mkdir -p /etc/services.d/99-run_forever
            cat <<EOF > /etc/services.d/99-run_forever/run
#!/bin/bash
while true
do
	sleep 86400
done
EOF
            chmod +x /etc/services.d/99-run_forever/run
        fi
    fi
}