import { nip04, type Event } from 'nostr-tools'
import { nostrService } from './nostr'
import type { AuthorPresentationDraft } from './articlePublisher'
import type { SimplePoolWithSub } from '@/types/nostr-tools-extended'
import { buildTags, extractTagsFromEvent, buildTagFilter } from './nostrTagSystem'

const RELAY_URL = process.env.NEXT_PUBLIC_NOSTR_RELAY_URL ?? 'wss://relay.damus.io'

export function buildPresentationEvent(draft: AuthorPresentationDraft, eventId: string, category: 'sciencefiction' | 'research' = 'sciencefiction') {
  return {
    kind: 1 as const,
    created_at: Math.floor(Date.now() / 1000),
    tags: buildTags({
      type: 'author',
      category,
      id: eventId,
      paywall: false,
      title: draft.title,
      preview: draft.preview,
      mainnetAddress: draft.mainnetAddress,
      totalSponsoring: 0,
      ...(draft.pictureUrl ? { pictureUrl: draft.pictureUrl } : {}),
    }),
    content: draft.content,
  }
}

export function parsePresentationEvent(event: Event): import('@/types/nostr').AuthorPresentationArticle | null {
  const tags = extractTagsFromEvent(event)

  // Check if it's an author type (tag is 'author' in English)
  if (tags.type !== 'author') {
    return null
  }

  return {
    id: tags.id ?? event.id,
    pubkey: event.pubkey,
    title: (tags.title as string | undefined) ?? 'Présentation',
    preview: (tags.preview as string | undefined) ?? event.content.substring(0, 200),
    content: event.content,
    createdAt: event.created_at,
    zapAmount: 0,
    paid: true,
    category: 'author-presentation',
    isPresentation: true,
    mainnetAddress: (tags.mainnetAddress as string | undefined) ?? '',
    totalSponsoring: (tags.totalSponsoring as number | undefined) ?? 0,
    ...(tags.pictureUrl ? { bannerUrl: tags.pictureUrl as string } : {}),
  }
}

export function fetchAuthorPresentationFromPool(
  pool: SimplePoolWithSub,
  pubkey: string
): Promise<import('@/types/nostr').AuthorPresentationArticle | null> {
  const filters = [
    {
      ...buildTagFilter({
        type: 'author',
        authorPubkey: pubkey,
      }),
      limit: 1,
    },
  ]

  return new Promise((resolve) => {
    let resolved = false
    const sub = pool.sub([RELAY_URL], filters)

    const finalize = (value: import('@/types/nostr').AuthorPresentationArticle | null) => {
      if (resolved) {
        return
      }
      resolved = true
      sub.unsub()
      resolve(value)
    }

    sub.on('event', (event: Event) => {
      const parsed = parsePresentationEvent(event)
      if (parsed) {
        finalize(parsed)
      }
    })

    sub.on('eose', () => finalize(null))
    setTimeout(() => finalize(null), 5000)
  })
}

export interface SendContentResult {
  success: boolean
  messageEventId?: string
  error?: string
  verified?: boolean
}

export async function sendEncryptedContent(
  articleId: string,
  recipientPubkey: string,
  storedContent: { content: string; authorPubkey: string; decryptionKey?: string; decryptionIV?: string },
  authorPrivateKey: string
): Promise<SendContentResult> {
  try {
    nostrService.setPrivateKey(authorPrivateKey)
    nostrService.setPublicKey(storedContent.authorPubkey)

    // Send the decryption key instead of the full content
    // The key is sent as JSON: { key: string, iv: string }
    const keyData = storedContent.decryptionKey && storedContent.decryptionIV
      ? JSON.stringify({ key: storedContent.decryptionKey, iv: storedContent.decryptionIV })
      : storedContent.content // Fallback to old behavior if keys are not available

    const encryptedKey = await Promise.resolve(nip04.encrypt(authorPrivateKey, recipientPubkey, keyData))

    const privateMessageEvent = {
      kind: 4,
      created_at: Math.floor(Date.now() / 1000),
      tags: [
        ['p', recipientPubkey],
        ['e', articleId],
      ],
      content: encryptedKey,
    }

    const publishedEvent = await nostrService.publishEvent(privateMessageEvent)

    if (!publishedEvent) {
      console.error('Failed to publish private message event', {
        articleId,
        recipientPubkey,
        authorPubkey: storedContent.authorPubkey,
      })
      return {
        success: false,
        error: 'Failed to publish private message event',
      }
    }

    const messageEventId = publishedEvent.id
    console.log('Private message published', {
      messageEventId,
      articleId,
      recipientPubkey,
      authorPubkey: storedContent.authorPubkey,
      timestamp: new Date().toISOString(),
    })

    const verified = await verifyPrivateMessagePublished(messageEventId, storedContent.authorPubkey, recipientPubkey, articleId)

    if (verified) {
      console.log('Private message verified on relay', {
        messageEventId,
        articleId,
        recipientPubkey,
      })
    } else {
      console.warn('Private message published but not yet verified on relay', {
        messageEventId,
        articleId,
        recipientPubkey,
      })
    }

    return {
      success: true,
      messageEventId,
      verified,
    }
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : 'Unknown error'
    console.error('Error sending encrypted content', {
      articleId,
      recipientPubkey,
      authorPubkey: storedContent.authorPubkey,
      error: errorMessage,
      timestamp: new Date().toISOString(),
    })
    return {
      success: false,
      error: errorMessage,
    }
  }
}

async function verifyPrivateMessagePublished(
  messageEventId: string,
  authorPubkey: string,
  recipientPubkey: string,
  articleId: string
): Promise<boolean> {
  try {
    const pool = nostrService.getPool()
    if (!pool) {
      console.error('Pool not initialized for message verification', {
        messageEventId,
        articleId,
        recipientPubkey,
      })
      return false
    }

    return new Promise((resolve) => {
      let resolved = false
      const filters = [
        {
          kinds: [4],
          ids: [messageEventId],
          authors: [authorPubkey],
          '#p': [recipientPubkey],
          '#e': [articleId],
          limit: 1,
        },
      ]

      const sub = (pool as import('@/types/nostr-tools-extended').SimplePoolWithSub).sub([RELAY_URL], filters)

      const finalize = (value: boolean) => {
        if (resolved) {
          return
        }
        resolved = true
        sub.unsub()
        resolve(value)
      }

      sub.on('event', (event) => {
        console.log('Private message verified on relay', {
          messageEventId: event.id,
          articleId,
          recipientPubkey,
          authorPubkey,
          timestamp: new Date().toISOString(),
        })
        finalize(true)
      })

      sub.on('eose', () => {
        console.warn('Private message not found on relay after EOSE', {
          messageEventId,
          articleId,
          recipientPubkey,
          timestamp: new Date().toISOString(),
        })
        finalize(false)
      })

      setTimeout(() => {
        if (!resolved) {
          console.warn('Timeout verifying private message on relay', {
            messageEventId,
            articleId,
            recipientPubkey,
            timestamp: new Date().toISOString(),
          })
          finalize(false)
        }
      }, 5000)
    })
  } catch (error) {
    console.error('Error verifying private message', {
      messageEventId,
      articleId,
      recipientPubkey,
      error: error instanceof Error ? error.message : 'Unknown error',
      timestamp: new Date().toISOString(),
    })
    return false
  }
}