/**
 * Migration: Add CameraDevice foreign key to devices
 *
 * Fixes: CameraDevice has device_id as varchar but no FK to devices table
 * Changes:
 * - Change device_id from varchar(100) to uuid
 * - Add FK constraint to devices table
 * - Change location from text to jsonb
 *
 * @type {import('node-pg-migrate').ColumnDefinitions | undefined}
 */
export const shorthands = undefined;

/**
 * @param pgm {import('node-pg-migrate').MigrationBuilder}
 * @param run {() => void | undefined}
 * @returns {Promise<void> | void}
 */
export const up = (pgm) => {
  console.log('Adding CameraDevice FK to devices...');

  // Step 1: Add new UUID device_id column
  pgm.addColumn('camera_devices', {
    device_uuid: {
      type: 'uuid',
      notNull: false,
      comment: 'Foreign key to devices table',
    },
  });

  // Step 2: Try to migrate existing data if device_id matches a device
  // Note: This assumes device_id contains hardware_id or similar identifier
  pgm.sql(`
    -- Try to match existing device_id to devices by hardware_id
    UPDATE camera_devices cd
    SET device_uuid = d.id
    FROM devices d
    WHERE cd.device_id = d.hardware_id
       OR cd.device_id = d.id::text;
  `);

  // Step 3: Rename old device_id to legacy_device_id
  pgm.renameColumn('camera_devices', 'device_id', 'legacy_device_id');

  // Step 4: Rename device_uuid to device_id
  pgm.renameColumn('camera_devices', 'device_uuid', 'device_id');

  // Step 5: Add FK constraint (nullable for cameras without matching device)
  pgm.addConstraint('camera_devices', 'camera_devices_device_id_fkey', {
    foreignKeys: {
      columns: 'device_id',
      references: 'devices(id)',
      onDelete: 'SET NULL',
    },
  });

  // Step 6: Add index on device_id
  pgm.createIndex('camera_devices', 'device_id', {
    name: 'idx_camera_devices_device_id',
    where: 'device_id IS NOT NULL',
  });

  // Step 7: Convert location from text to jsonb
  pgm.addColumn('camera_devices', {
    location_jsonb: {
      type: 'jsonb',
      notNull: false,
      comment: 'Structured location data {latitude, longitude, altitude, site_name}',
    },
  });

  // Migrate existing location text to jsonb
  pgm.sql(`
    UPDATE camera_devices
    SET location_jsonb = jsonb_build_object('site_name', location)
    WHERE location IS NOT NULL AND location != '';
  `);

  // Rename columns
  pgm.renameColumn('camera_devices', 'location', 'legacy_location');
  pgm.renameColumn('camera_devices', 'location_jsonb', 'location');

  console.log('CameraDevice FK and location migration complete.');
};

/**
 * @param pgm {import('node-pg-migrate').MigrationBuilder}
 * @param run {() => void | undefined}
 * @returns {Promise<void> | void}
 */
export const down = (pgm) => {
  console.log('Rolling back CameraDevice FK changes...');

  // Restore location
  pgm.renameColumn('camera_devices', 'location', 'location_jsonb');
  pgm.renameColumn('camera_devices', 'legacy_location', 'location');
  pgm.dropColumn('camera_devices', 'location_jsonb', { ifExists: true });

  // Restore device_id
  pgm.dropIndex('camera_devices', 'device_id', {
    name: 'idx_camera_devices_device_id',
    ifExists: true,
  });

  pgm.dropConstraint('camera_devices', 'camera_devices_device_id_fkey', {
    ifExists: true,
  });

  pgm.renameColumn('camera_devices', 'device_id', 'device_uuid');
  pgm.renameColumn('camera_devices', 'legacy_device_id', 'device_id');
  pgm.dropColumn('camera_devices', 'device_uuid', { ifExists: true });

  console.log('CameraDevice FK rollback complete.');
};