import type { Event, Filter } from 'nostr-tools'
import { SimplePool } from 'nostr-tools'

/**
 * Extended SimplePool interface that includes the sub method
 * The sub method exists in nostr-tools but is not properly typed in the TypeScript definitions
 */
export interface SimplePoolWithSub extends SimplePool {
  sub(relays: string[], filters: Filter[]): {
    on(event: 'event', callback: (event: Event) => void): void
    on(event: 'eose', callback: () => void): void
    unsub(): void
  }
}

/**
 * Type guard to check if a SimplePool has the sub method
 */
export function hasSubMethod(pool: SimplePool): pool is SimplePoolWithSub {
  return typeof (pool as SimplePoolWithSub).sub === 'function'
}