import { removeUndefined, sanitizeRelayUrl } from "@snort/shared"
import EventKind from "./event-kind"
import type { FullRelaySettings, NostrEvent } from "./nostr"

export function parseRelayTag(tag: Array<string>) {
  if (tag[0] !== "r") return
  const url = sanitizeRelayUrl(tag[1])
  if (url) {
    return {
      url,
      settings: {
        read: tag[2] === "read" || tag[2] === undefined,
        write: tag[2] === "write" || tag[2] === undefined,
      },
    } as FullRelaySettings
  }
}

export function parseRelayTags(tag: Array<Array<string>>) {
  return removeUndefined(tag.map(parseRelayTag))
}

export function parseRelaysFromKind(ev: NostrEvent) {
  if (ev.kind === EventKind.ContactList) {
    let relaysInContent: Record<string, { read: boolean; write: boolean }> | undefined
    try {
      relaysInContent =
        ev.content.length > 0
          ? (JSON.parse(ev.content) as Record<string, { read: boolean; write: boolean }>)
          : undefined
    } catch {
      // Malformed kind-3 content — treat as if no relay list in content
      relaysInContent = undefined
    }
    if (relaysInContent) {
      return removeUndefined(
        Object.entries(relaysInContent).map(([k, v]) => {
          const url = sanitizeRelayUrl(k)
          if (url) {
            return {
              url,
              settings: {
                read: v.read,
                write: v.write,
              },
            } as FullRelaySettings
          }
        }),
      )
    }
  } else if (ev.kind === EventKind.Relays) {
    return parseRelayTags(ev.tags)
  }
}

/**
 * Convert relay settings into NIP-65 relay tag
 */
export function settingsToRelayTag(rx: FullRelaySettings) {
  const rTag = ["r", rx.url]
  if (rx.settings.read && !rx.settings.write) {
    rTag.push("read")
  }
  if (rx.settings.write && !rx.settings.read) {
    rTag.push("write")
  }
  if (rx.settings.read || rx.settings.write) {
    return rTag
  }
}