#!/bin/bash

set -e

# clickhouse-backup output lives inside the event-data volume (snapshotted via
# backupbot.backup.volumes.event-data.path). Restoring the raw data files under a
# running server is unsafe, so restore performs a logical restore instead.
BACKUP_DIR=/var/lib/clickhouse/backup/events
MIGRATIONS_TSV="$BACKUP_DIR/schema_migrations.tsv"

backup() {
  clickhouse-backup create events
  # schema_migrations is a TinyLog table — clickhouse-backup only FREEZEs MergeTree
  # data, so its rows aren't captured. Export them alongside the backup, else a restore
  # leaves the ledger empty and the next boot re-runs every migration (DUPLICATE_COLUMN).
  clickhouse-client --query "SELECT * FROM plausible_events_db.schema_migrations FORMAT TSV" > "$MIGRATIONS_TSV"
}

backup_cleanup() {
  rm -rf "$BACKUP_DIR"
}

restore() {
  clickhouse-backup restore --rm events
  clickhouse-client --query "TRUNCATE TABLE plausible_events_db.schema_migrations"
  clickhouse-client --query "INSERT INTO plausible_events_db.schema_migrations FORMAT TSV" < "$MIGRATIONS_TSV"
  rm -rf "$BACKUP_DIR"
}

"$@"