#!/bin/bash
set -e

echo "== Creating publication in each database =="

for db in $(psql -Atqc "SELECT datname FROM pg_database WHERE datallowconn AND datname NOT IN ('template0','template1')"); do
  echo "Processing DB: $db"

  # Create publication (idempotent)
  psql -d "$db" -v ON_ERROR_STOP=1 <<SQL
DO \$\$
BEGIN
  IF NOT EXISTS (
    SELECT 1 FROM pg_publication WHERE pubname = 'migrate_pub'
  ) THEN
    CREATE PUBLICATION migrate_pub FOR ALL TABLES;
  END IF;
END
\$\$;
SQL

  # Create logical replication slot (idempotent-ish)
  SLOT="migrate_slot_${db}"

  if ! psql -d "$db" -Atqc "SELECT 1 FROM pg_replication_slots WHERE slot_name = '$SLOT'" | grep -q 1; then
    echo "  Creating slot: $SLOT"
    psql -d "$db" -c "SELECT pg_create_logical_replication_slot('$SLOT', 'pgoutput');"
  else
    echo "  Slot already exists: $SLOT"
  fi

done

echo "== Done =="