sigit.io/src/controllers/MetadataController.ts

import {
  Filter,
  SimplePool,
  VerifiedEvent,
  kinds,
  validateEvent,
  verifyEvent,
  Event
} from 'nostr-tools'
import { ProfileMetadata } from '../types'
import { NostrController } from '.'
import { toast } from 'react-toastify'

export class MetadataController {
  private nostrController: NostrController
  private specialMetadataRelay = 'wss://purplepag.es'

  constructor() {
    this.nostrController = NostrController.getInstance()
  }

  public findMetadata = async (hexKey: string) => {
    const mostPopularRelays = import.meta.env.VITE_MOST_POPULAR_RELAYS
    const hardcodedPopularRelays = (mostPopularRelays || '').split(' ')
    const relays = [...hardcodedPopularRelays, this.specialMetadataRelay]

    const eventFilter: Filter = {
      kinds: [kinds.Metadata],
      authors: [hexKey]
    }

    const pool = new SimplePool()

    const events = await pool.querySync(relays, eventFilter).catch((err) => {
      console.error(err)
      return null
    })

    if (events && events.length) {
      events.sort((a, b) => b.created_at - a.created_at)

      for (const event of events) {
        if (validateEvent(event) && verifyEvent(event)) {
          return event
        }
      }
    }

    throw new Error('Mo metadata found.')
  }

  public extractProfileMetadataContent = (event: VerifiedEvent) => {
    try {
      return JSON.parse(event.content) as ProfileMetadata
    } catch (error) {
      console.log('error in parsing metadata event content :>> ', error)
      return null
    }
  }

  /**
   * Function will not sign provided event if the SIG exists
   */
  public publishMetadataEvent = async (event: Event) => {
    let signedMetadataEvent = event

    if (event.sig.length < 1) {
      const timestamp = Math.floor(Date.now() / 1000)

      // Metadata event to publish to the nquiz relay
      const newMetadataEvent: Event = {
        ...event,
        created_at: timestamp
      }

      signedMetadataEvent = await this.nostrController.signEvent(
        newMetadataEvent
      )
    }

    await this.nostrController
      .publishEvent(signedMetadataEvent, this.specialMetadataRelay)
      .then((res) => {
        toast.success(`Metadata: ${res}`)
      })
      .catch((err) => {
        toast.error(err.message)
      })
  }

  public validate = (event: Event) => validateEvent(event) && verifyEvent(event)
}