#!/usr/bin/env bash
#
# split-databases.sh — Migrate from single appdb to per-domain databases.
#
# Prerequisites:
#   - All apps stopped (5-min maintenance window)
#   - init-databases.sql already run (CREATE DATABASE db_*)
#   - Run from a host that can reach the Postgres container
#
# Usage:
#   PGHOST=db PGUSER=postgres PGPASSWORD=change-me bash split-databases.sh
#
set -euo pipefail

SOURCE_DB="${SOURCE_DB:-appdb}"

# ── Table → database mapping ───────────────────────────────────────────────

declare -A DB_TABLES

DB_TABLES[db_account]="
  users
  magic_links
  oauth_codes
  oauth_grants
  ghost_labels
  user_labels
  ghost_newsletters
  user_newsletters
  ghost_tiers
  ghost_subscriptions
  kv
"

DB_TABLES[db_blog]="
  authors
  tags
  posts
  post_authors
  post_tags
  post_likes
  menu_items
  menu_nodes
  container_relations
  page_configs
"

DB_TABLES[db_market]="
  products
  product_images
  product_sections
  product_labels
  product_stickers
  product_attributes
  product_nutrition
  product_allergens
  product_likes
  product_logs
  market_places
  nav_tops
  nav_subs
  listings
  listing_items
  link_errors
  link_externals
  subcategory_redirects
  cart_items
  orders
  order_items
"

# db_cart merged into db_market — cart and market share the same bounded context
# (commerce). Cart needs direct read access to products/market_places.

DB_TABLES[db_events]="
  calendars
  calendar_slots
  calendar_entries
  calendar_entry_posts
  ticket_types
  tickets
"

DB_TABLES[db_federation]="
  ap_anchors
  ap_actor_profiles
  ap_activities
  ap_followers
  ap_inbox_items
  ap_remote_actors
  ap_following
  ap_remote_posts
  ap_local_posts
  ap_interactions
  ap_notifications
  ap_delivery_log
  ipfs_pins
"

# ── Migrate each domain ────────────────────────────────────────────────────

for target_db in db_account db_blog db_market db_events db_federation; do
  tables="${DB_TABLES[$target_db]}"
  table_list=""
  for t in $tables; do
    table_list="$table_list --table=$t"
  done

  echo "=== Migrating $target_db ==="
  echo "  Tables: $(echo $tables | tr '\n' ' ')"

  # Dump schema + data for these tables from the source DB
  pg_dump "$SOURCE_DB" $table_list --no-owner --no-privileges \
    | psql -q "$target_db"

  echo "  Done."
done

# ── Stamp Alembic head in each domain DB ──────────────────────────────────

echo ""
echo "=== Stamping Alembic head in each DB ==="
for target_db in db_account db_blog db_market db_events db_federation; do
  # Create alembic_version table and stamp current head
  psql -q "$target_db" <<'SQL'
    CREATE TABLE IF NOT EXISTS alembic_version (
      version_num VARCHAR(32) NOT NULL,
      CONSTRAINT alembic_version_pkc PRIMARY KEY (version_num)
    );
    DELETE FROM alembic_version;
    INSERT INTO alembic_version (version_num) VALUES ('w3u1q9r0s1');
SQL
  echo "  $target_db stamped at w3u1q9r0s1"
done

echo ""
echo "=== Migration complete ==="
echo ""
echo "Next steps:"
echo "  1. Update docker-compose.yml — set per-app DATABASE_URL to the new DBs"
echo "  2. Remove schema_sql config (no longer needed)"
echo "  3. Redeploy all services"
echo ""
echo "Per-app DATABASE_URL values:"
echo "  blog:       postgresql+asyncpg://postgres:change-me@db:5432/db_blog"
echo "  market:     postgresql+asyncpg://postgres:change-me@db:5432/db_market"
echo "  cart:       postgresql+asyncpg://postgres:change-me@db:5432/db_market  (shared with market)"
echo "  events:     postgresql+asyncpg://postgres:change-me@db:5432/db_events"
echo "  federation: postgresql+asyncpg://postgres:change-me@db:5432/db_federation"
echo "  account:    postgresql+asyncpg://postgres:change-me@db:5432/db_account"
echo ""
echo "  DATABASE_URL_ACCOUNT:    postgresql+asyncpg://postgres:change-me@db:5432/db_account"
echo "  DATABASE_URL_FEDERATION: postgresql+asyncpg://postgres:change-me@db:5432/db_federation"