import type { EventTemplate, Event } from 'nostr-tools'
import { getEventHash, signEvent } from 'nostr-tools'
import { nostrConnectService } from './nostrconnect'
import { nostrService } from './nostr'

/**
 * Remote signer using NostrConnect
 * Supports both direct signing (if private key available) and remote signing via bridge
 */
export class NostrRemoteSigner {
  /**
   * Sign an event template
   * Requires private key to be available
   */
  async signEvent(eventTemplate: EventTemplate): Promise<Event | null> {
    // Get the event hash first
    const eventId = getEventHash(eventTemplate)

    // Try to get private key from nostrService (if available from NostrConnect)
    const privateKey = nostrService.getPrivateKey()

    if (privateKey) {
      // Use direct signing if private key is available
      const event = {
        ...eventTemplate,
        id: eventId,
        sig: signEvent(eventTemplate, privateKey),
      } as Event

      return event
    }

    // If no private key, remote signing is required
    // Note: use.nsec.app might not support direct signing via postMessage
    throw new Error(
      'Private key required for signing. ' +
      'Please use a NostrConnect wallet that provides signing capabilities, ' +
      'or ensure your wallet is properly connected.'
    )
  }

  /**
   * Check if remote signing is available
   */
  isAvailable(): boolean {
    const state = nostrConnectService.getState()
    return state.connected && !!state.pubkey
  }

  /**
   * Check if direct signing (with private key) is available
   */
  isDirectSigningAvailable(): boolean {
    return !!nostrService.getPrivateKey()
  }
}

export const nostrRemoteSigner = new NostrRemoteSigner()