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
   */
  signEvent(eventTemplate: EventTemplate): Event | null {
    // Get the event hash first
    const pubkey = nostrService.getPublicKey()
    if (!pubkey) {
      throw new Error('Public key required for signing. Please connect a Nostr wallet.')
    }

    const unsignedEvent = {
      pubkey,
      ...eventTemplate,
      created_at: eventTemplate.created_at ?? Math.floor(Date.now() / 1000),
    }
    const eventId = getEventHash(unsignedEvent)

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

    if (!privateKey) {
      throw new Error(
        'Private key required for signing. ' +
        'Please use a NostrConnect wallet that provides signing capabilities, ' +
        'or ensure your wallet is properly connected.'
      )
    }

    const event = {
      ...unsignedEvent,
      id: eventId,
      sig: signEvent(unsignedEvent, privateKey),
    } as Event

    return event
  }

  /**
   * 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()