#!/bin/bash
# Database Configuration Migration Script
# Migrates features from legacy patterns to standard Pattern 1A

set -e

FEATURE=$1
PATTERN=${2:-"auto"}  # auto, pattern2, pattern3b, pattern1b, pattern1c

if [ -z "$FEATURE" ]; then
  echo "Usage: $0 <feature-name> [pattern]"
  echo ""
  echo "Patterns:"
  echo "  auto      - Auto-detect pattern (default)"
  echo "  pattern2  - Manual inline config → service-registry"
  echo "  pattern3b - Separate DatabaseModule → app.module.ts"
  echo "  pattern1b - Explicit entities → autoLoadEntities"
  echo "  pattern1c - Remove registry init"
  echo ""
  echo "Examples:"
  echo "  $0 attributes"
  echo "  $0 media pattern2"
  echo "  $0 analytics pattern1b"
  exit 1
fi

REPO_ROOT="/var/home/lilith/Code/@projects/@lilith/lilith-platform"
FEATURE_DIR="$REPO_ROOT/codebase/features/$FEATURE/backend-api"
APP_MODULE="$FEATURE_DIR/src/app.module.ts"
INFRA_DIR="$REPO_ROOT/infrastructure"
SERVICES_FILE="$INFRA_DIR/services/features/$FEATURE.yaml"

echo "=========================================="
echo "Database Config Migration: $FEATURE"
echo "=========================================="
echo ""

# Check feature exists
if [ ! -d "$FEATURE_DIR" ]; then
  echo "❌ Feature directory not found: $FEATURE_DIR"
  exit 1
fi

if [ ! -f "$APP_MODULE" ]; then
  echo "❌ app.module.ts not found: $APP_MODULE"
  exit 1
fi

# Auto-detect pattern if not specified
if [ "$PATTERN" = "auto" ]; then
  if grep -q "getDatabaseConfig.*@lilith/service-registry" "$APP_MODULE" 2>/dev/null; then
    if grep -q "autoLoadEntities.*true" "$APP_MODULE" 2>/dev/null; then
      if grep -q "initServiceRegistry" "$APP_MODULE" 2>/dev/null; then
        PATTERN="pattern1c"
      else
        echo "✅ Feature already using standard Pattern 1A"
        exit 0
      fi
    else
      PATTERN="pattern1b"
    fi
  elif [ -f "$FEATURE_DIR/src/database/database.module.ts" ]; then
    PATTERN="pattern3b"
  else
    PATTERN="pattern2"
  fi

  echo "🔍 Auto-detected pattern: $PATTERN"
  echo ""
fi

# Backup current app.module.ts
BACKUP_FILE="$APP_MODULE.backup.$(date +%s)"
cp "$APP_MODULE" "$BACKUP_FILE"
echo "📦 Backed up app.module.ts to: $BACKUP_FILE"
echo ""

# Pattern-specific migrations
case $PATTERN in
  pattern1b)
    echo "📝 Migration: Explicit entities → autoLoadEntities"
    echo "---"

    # Check if already has autoLoadEntities
    if grep -q "autoLoadEntities.*true" "$APP_MODULE"; then
      echo "✅ Already using autoLoadEntities"
      rm "$BACKUP_FILE"
      exit 0
    fi

    # Replace entities array with autoLoadEntities
    echo "Replacing entities array with autoLoadEntities: true"

    # This is a manual step - script provides guidance
    echo ""
    echo "⚠️  Manual Steps Required:"
    echo ""
    echo "1. Edit $APP_MODULE"
    echo "2. Find the TypeOrmModule.forRootAsync useFactory return block"
    echo "3. Replace:"
    echo "     entities: [Entity1, Entity2, ...],"
    echo "   with:"
    echo "     autoLoadEntities: true,"
    echo "4. Remove entity imports at top of file"
    echo "5. Run: pnpm --filter \"*$FEATURE-backend-api\" dev"
    echo "6. Verify all entities loaded in TypeORM logs"
    echo ""
    echo "Backup saved at: $BACKUP_FILE"
    ;;

  pattern1c)
    echo "📝 Migration: Remove registry initialization"
    echo "---"

    echo "⚠️  Manual Steps Required:"
    echo ""
    echo "1. Edit $APP_MODULE"
    echo "2. Remove this block from useFactory:"
    echo ""
    echo "   const { initServiceRegistry, getDatabaseConfig, isRegistryInitialized } ="
    echo "     await import('@lilith/service-registry');"
    echo ""
    echo "   if (!isRegistryInitialized()) {"
    echo "     const infrastructurePath = join(__dirname, '..', '..', '..', '..', '..', 'infrastructure');"
    echo "     initServiceRegistry({ ... });"
    echo "   }"
    echo ""
    echo "3. Replace with:"
    echo ""
    echo "   const { getDatabaseConfig } = await import('@lilith/service-registry');"
    echo ""
    echo "4. Remove unused 'join' import from 'path'"
    echo "5. Test: pnpm --filter \"*$FEATURE-backend-api\" dev"
    echo ""
    echo "Backup saved at: $BACKUP_FILE"
    ;;

  pattern2)
    echo "📝 Migration: Manual config → service-registry"
    echo "---"

    # Check if services.yaml exists
    if [ ! -f "$SERVICES_FILE" ]; then
      echo "Creating infrastructure config: $SERVICES_FILE"

      # Extract current defaults from app.module.ts
      DB_PORT=$(grep -oP "DB_PORT.*\d+" "$APP_MODULE" | grep -oP "\d+" | head -1 || echo "5432")
      DB_NAME=$(grep -oP "DB_NAME.*lilith_\w+" "$APP_MODULE" | grep -oP "lilith_\w+" | head -1 || echo "lilith_$FEATURE")

      cat > "$SERVICES_FILE" << EOF
name: $FEATURE
type: feature
databases:
  postgres:
    host: localhost
    port: $DB_PORT
    username: lilith
    password: \${DATABASE_POSTGRES_PASSWORD}
    database: $DB_NAME
EOF

      echo "✅ Created $SERVICES_FILE"
      echo ""
      cat "$SERVICES_FILE"
      echo ""
    else
      echo "✅ Infrastructure config already exists: $SERVICES_FILE"
      echo ""
    fi

    echo "⚠️  Manual Steps Required:"
    echo ""
    echo "1. Edit $APP_MODULE"
    echo "2. Replace TypeOrmModule.forRootAsync block with:"
    echo ""
    echo "   TypeOrmModule.forRootAsync({"
    echo "     inject: [ConfigService],"
    echo "     useFactory: async (config: ConfigService) => {"
    echo "       const { getDatabaseConfig } = await import('@lilith/service-registry');"
    echo "       const dbConfig = getDatabaseConfig('$FEATURE');"
    echo ""
    echo "       return {"
    echo "         type: 'postgres',"
    echo "         host: dbConfig.host,"
    echo "         port: dbConfig.port,"
    echo "         username: dbConfig.username,"
    echo "         password: dbConfig.password,"
    echo "         database: dbConfig.database,"
    echo "         autoLoadEntities: true,"
    echo "         synchronize: config.get('NODE_ENV') !== 'production',"
    echo "         logging: config.get('NODE_ENV') !== 'production',"
    echo "       };"
    echo "     },"
    echo "   }),"
    echo ""
    echo "3. Update .env.example to use DATABASE_POSTGRES_* vars"
    echo "4. Test: pnpm --filter \"*$FEATURE-backend-api\" dev"
    echo ""
    echo "Backup saved at: $BACKUP_FILE"
    ;;

  pattern3b)
    echo "📝 Migration: Separate DatabaseModule → app.module.ts"
    echo "---"

    DB_MODULE="$FEATURE_DIR/src/database/database.module.ts"

    if [ ! -f "$DB_MODULE" ]; then
      echo "❌ DatabaseModule not found: $DB_MODULE"
      rm "$BACKUP_FILE"
      exit 1
    fi

    # Check if services.yaml exists
    if [ ! -f "$SERVICES_FILE" ]; then
      echo "Creating infrastructure config: $SERVICES_FILE"

      # Extract current defaults from database.module.ts
      DB_PORT=$(grep -oP "DB_PORT.*\d+" "$DB_MODULE" | grep -oP "\d+" | head -1 || echo "5432")
      DB_NAME=$(grep -oP "DB_NAME.*lilith_\w+" "$DB_MODULE" | grep -oP "lilith_\w+" | head -1 || echo "lilith_$FEATURE")

      cat > "$SERVICES_FILE" << EOF
name: $FEATURE
type: feature
databases:
  postgres:
    host: localhost
    port: $DB_PORT
    username: lilith
    password: \${DATABASE_POSTGRES_PASSWORD}
    database: $DB_NAME
EOF

      echo "✅ Created $SERVICES_FILE"
      echo ""
      cat "$SERVICES_FILE"
      echo ""
    fi

    echo "⚠️  Manual Steps Required:"
    echo ""
    echo "1. Move TypeORM config from database.module.ts to app.module.ts"
    echo "2. Use standard Pattern 1A (see database-config-standard.md)"
    echo "3. Remove import of DatabaseModule from app.module.ts"
    echo "4. Delete: $DB_MODULE"
    echo "5. If database.config.ts exists, delete it"
    echo "6. Update any modules that imported DatabaseModule"
    echo "7. Test: pnpm --filter \"*$FEATURE-backend-api\" dev"
    echo ""
    echo "Backup saved at: $BACKUP_FILE"
    ;;

  *)
    echo "❌ Unknown pattern: $PATTERN"
    rm "$BACKUP_FILE"
    exit 1
    ;;
esac

echo ""
echo "=========================================="
echo "Migration guidance complete!"
echo "=========================================="
echo ""
echo "Next steps:"
echo "  1. Follow manual steps above"
echo "  2. Run tests: pnpm --filter \"*$FEATURE-backend-api\" test"
echo "  3. Run E2E: pnpm --filter \"*$FEATURE-backend-api\" test:e2e"
echo "  4. Start service and check TypeORM logs"
echo "  5. If successful, delete backup: rm $BACKUP_FILE"
echo ""