#!/usr/bin/env bash
# Fix PostgreSQL "collation version mismatch" (e.g. DB created with 2.36, OS provides 2.41).
# Reindexes then refreshes collation version. REINDEX will be canceled if Gitea (or other
# clients) keep using the DB, so either stop Gitea first or use --terminate-connections.
#
# Usage (from host):
#   ./fix-postgres-collation-version.sh <postgres_container_name>
#   ./fix-postgres-collation-version.sh <postgres_container_name> gitea
#   ./fix-postgres-collation-version.sh <postgres_container_name> gitea --terminate-connections
#
# Option: --terminate-connections  Terminate all other sessions on the DB so REINDEX can
#                                  run without being canceled. Gitea will disconnect; restart it after.


# REINDEX DATABASE gitea;
# ALTER DATABASE gitea REFRESH COLLATION VERSION;


set -e
CONTAINER="${1:?Usage: $0 <postgres_container_name> [database_name] [--terminate-connections]}"
DB="${2:-gitea}"
TERMINATE=""
if [[ "$2" == "--terminate-connections" ]]; then
  TERMINATE=1
  DB="gitea"
elif [[ "$3" == "--terminate-connections" ]]; then
  TERMINATE=1
fi

if [[ -z "$TERMINATE" ]]; then
  echo "Stop the Gitea container (and any other app using database $DB) before continuing,"
  echo "otherwise REINDEX may be canceled. Press Enter when ready, or Ctrl+C to abort."
  read -r
fi

if [[ -n "$TERMINATE" ]]; then
  echo "Terminating other connections to $DB..."
  docker exec "$CONTAINER" psql -U postgres -d "$DB" -c "SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '$DB' AND pid <> pg_backend_pid();" || true
  sleep 2
fi

echo "Reindexing database $DB (may take a while)..."
docker exec "$CONTAINER" psql -U postgres -d "$DB" -c "REINDEX DATABASE $DB;"

echo "Refreshing collation version..."
docker exec "$CONTAINER" psql -U postgres -d "$DB" -c "ALTER DATABASE $DB REFRESH COLLATION VERSION;"

echo "Done. Start Gitea again if you stopped it or used --terminate-connections."