import { vi } from 'vitest';
import type { FastifyInstance } from 'fastify';
import type { NodePgDatabase } from 'drizzle-orm/node-postgres';
import type * as schema from '../src/db/schema/index.js';

export type MockDb = {
  select: ReturnType<NodePgDatabase<typeof schema>['select']>;
  insert: ReturnType<NodePgDatabase<typeof schema>['insert']>;
  update: ReturnType<NodePgDatabase<typeof schema>['update']>;
  delete: ReturnType<NodePgDatabase<typeof schema>['delete']>;
};

/**
 * Create a chainable mock for Drizzle DB operations.
 * Configure chain terminals (limit, returning) to resolve to desired values.
 * Example: mockDb.select.mockReturnValue({ from: vi.fn().mockReturnValue({ where: vi.fn().mockReturnValue({ limit: vi.fn().mockResolvedValue([user]) }) }) })
 */
export function createMockDb(): MockDb {
  const chain = {
    from: vi.fn().mockReturnThis(),
    where: vi.fn().mockReturnThis(),
    values: vi.fn().mockReturnThis(),
    set: vi.fn().mockReturnThis(),
    orderBy: vi.fn().mockReturnThis(),
    limit: vi.fn().mockReturnThis(),
    returning: vi.fn().mockReturnThis(),
  };

  return {
    select: vi.fn().mockReturnValue(chain),
    insert: vi.fn().mockReturnValue(chain),
    update: vi.fn().mockReturnValue(chain),
    delete: vi.fn().mockReturnValue(chain),
  } as unknown as MockDb;
}

/**
 * Create a minimal mock Fastify app with db for route/integration tests.
 * Use buildApp() from app.ts for full integration tests.
 */
export function createMockApp(): FastifyInstance & { db: MockDb } {
  return {
    db: createMockDb(),
    log: {
      child: () => ({
        debug: () => {},
        info: () => {},
        warn: () => {},
        error: () => {},
        trace: () => {},
        fatal: () => {},
      }),
      debug: () => {},
      info: () => {},
      warn: () => {},
      error: () => {},
      trace: () => {},
      fatal: () => {},
    },
  } as FastifyInstance & { db: MockDb };
}