import { MigrationInterface, QueryRunner } from 'typeorm';

export class AddDefaultTenant1772329237979 implements MigrationInterface {
  public async up(queryRunner: QueryRunner): Promise<void> {
    // 1. Insert "Default" tenant if it doesn't exist.
    // We use a predefined UUID or let the DB generate it.
    // Assuming Postgres/MySQL compatible uuid generation isn't strictly standard here,
    // we'll insert and get the ID back, or use a workaround for SQLite if it's SQLite.
    // Actually, since this is a TypeORM setup, we can use standard SQL.

    // This is a bit tricky to write purely in SQL that works across all DBs (SQLite/Postgres/MySQL)
    // without knowing the exact DB.  AuraK seems to use SQLite locally by default.
    // First, check if there's any record in the tenant table.
    const tenants = await queryRunner.query(
      `SELECT id FROM "tenant" WHERE "name" = 'Default'`,
    );
    let defaultTenantId;

    if (tenants && tenants.length > 0) {
      defaultTenantId = tenants[0].id;
    } else {
      // Create it with a JS generated UUID to be database agnostic
      const crypto = require('crypto');
      defaultTenantId = crypto.randomUUID();
      const now = new Date().toISOString();
      await queryRunner.query(
        `INSERT INTO "tenant" (id, name, description, "createdAt", "updatedAt") VALUES (?, ?, ?, ?, ?)`,
        [
          defaultTenantId,
          'Default',
          'Default tenant created by migration',
          now,
          now,
        ],
      );

      // Create tenant settings
      const settingsId = crypto.randomUUID();
      await queryRunner.query(
        `INSERT INTO "tenant_setting" (id, "tenantId", "createdAt", "updatedAt") VALUES (?, ?, ?, ?)`,
        [settingsId, defaultTenantId, now, now],
      );
    }

    // 2. Assign the Default tenant to all relevant existing records that have no tenantId
    const tablesToUpdate = [
      'user',
      'knowledge_base',
      'knowledge_group',
      'search_history',
      'note',
      'model_config',
    ];

    for (const table of tablesToUpdate) {
      // Check if table exists first (some might be missing if DB is fresh)
      try {
        await queryRunner.query(
          `UPDATE "${table}" SET "tenantId" = ? WHERE "tenantId" IS NULL`,
          [defaultTenantId],
        );
      } catch (e) {
        console.warn(
          `Could not update table ${table}, it might not exist or the tenantId column might not exist yet.`,
        );
      }
    }
  }

  public async down(queryRunner: QueryRunner): Promise<void> {
    // We don't necessarily want to delete the tenant data in a down migration
    // as it would orphan all the records or require setting them to NULL.
    // But for completeness, we can set them back to NULL.

    const tablesToUpdate = [
      'user',
      'knowledge_base',
      'knowledge_group',
      'search_history',
      'note',
      'model_config',
    ];
    for (const table of tablesToUpdate) {
      try {
        await queryRunner.query(`UPDATE "${table}" SET "tenantId" = NULL`);
      } catch (e) {
        // Ignore
      }
    }
  }
}