nip58.ts

import { Event, EventTemplate } from './core.ts'
import {
  BadgeAward as BadgeAwardKind,
  BadgeDefinition as BadgeDefinitionKind,
  ProfileBadges as ProfileBadgesKind,
} from './kinds.ts'

/**
 * Represents the structure for defining a badge within the Nostr network.
 * This structure is used to create templates for badge definition events,
 * facilitating the recognition and awarding of badges to users for various achievements.
 */
export type BadgeDefinition = {
  /**
   * A unique identifier for the badge. This is used to distinguish badges
   * from one another and should be unique across all badge definitions.
   * Typically, this could be a short, descriptive string.
   */
  d: string

  /**
   * An optional short name for the badge. This provides a human-readable
   * title for the badge, making it easier to recognize and refer to.
   */
  name?: string

  /**
   * An optional description for the badge. This field can be used to
   * provide more detailed information about the badge, such as the criteria
   * for its awarding or its significance.
   */
  description?: string

  /**
   * An optional image URL and dimensions for the badge. The first element
   * of the tuple is the URL pointing to a high-resolution image representing
   * the badge, and the second element specifies the image's dimensions in
   * the format "widthxheight". The recommended dimensions are 1024x1024 pixels.
   */
  image?: [string, string]

  /**
   * An optional list of thumbnail images for the badge. Each element in the
   * array is a tuple, where the first element is the URL pointing to a thumbnail
   * version of the badge image, and the second element specifies the thumbnail's
   * dimensions in the format "widthxheight". Multiple thumbnails can be provided
   * to support different display sizes.
   */
  thumbs?: Array<[string, string]>
}

/**
 * Represents the structure for awarding a badge to one or more recipients
 * within the Nostr network. This structure is used to create templates for
 * badge award events, which are immutable and signify the recognition of
 * individuals' achievements or contributions.
 */
export type BadgeAward = {
  /**
   * A reference to the Badge Definition event. This is typically composed
   * of the event ID of the badge definition. It establishes a clear linkage
   * between the badge being awarded and its original definition, ensuring
   * that recipients are awarded the correct badge.
   */
  a: string

  /**
   * An array of p tags, each containing a pubkey and its associated relays.
   */
  p: string[][]
}

/**
 * Represents the collection of badges a user chooses to display on their profile.
 * This structure is crucial for applications that allow users to showcase achievements
 * or recognitions in the form of badges, following the specifications of NIP-58.
 */
export type ProfileBadges = {
  /**
   * A unique identifier for the profile badges collection. According to NIP-58,
   * this should be set to "profile_badges" to differentiate it from other event types.
   */
  d: 'profile_badges'

  /**
   * A list of badges that the user has elected to display on their profile. Each item
   * in the array represents a specific badge, including references to both its definition
   * and the award event.
   */
  badges: Array<{
    /**
     * The event address of the badge definition. This is a reference to the specific badge
     * being displayed, linking back to the badge's original definition event. It allows
     * clients to fetch and display the badge's details, such as its name, description,
     * and image.
     */
    a: string

    /**
     * The event id of the badge award with corresponding relays. This references the event
     * in which the badge was awarded to the user. It is crucial for verifying the
     * authenticity of the badge display, ensuring that the user was indeed awarded the
     * badge they are choosing to display.
     */
    e: string[]
  }>
}

/**
 * Generates an EventTemplate based on the provided BadgeDefinition.
 *
 * @param {BadgeDefinition} badgeDefinition - The BadgeDefinition object.
 * @returns {EventTemplate} - The generated EventTemplate object.
 */
export function generateBadgeDefinitionEventTemplate({
  d,
  description,
  image,
  name,
  thumbs,
}: BadgeDefinition): EventTemplate {
  // Mandatory tags
  const tags: string[][] = [['d', d]]

  // Append optional tags
  name && tags.push(['name', name])
  description && tags.push(['description', description])
  image && tags.push(['image', ...image])
  if (thumbs) {
    for (const thumb of thumbs) {
      tags.push(['thumb', ...thumb])
    }
  }

  // Construct the EventTemplate object
  const eventTemplate: EventTemplate = {
    content: '',
    created_at: Math.floor(Date.now() / 1000),
    kind: BadgeDefinitionKind,
    tags,
  }

  return eventTemplate
}

/**
 * Validates a badge definition event.
 *
 * @param event - The event to validate.
 * @returns A boolean indicating whether the event is a valid badge definition event.
 */
export function validateBadgeDefinitionEvent(event: Event): boolean {
  if (event.kind !== BadgeDefinitionKind) return false

  const requiredTags = ['d'] as const
  for (const tag of requiredTags) {
    if (!event.tags.find(([t]) => t == tag)) return false
  }

  return true
}

/**
 * Generates an EventTemplate based on the provided BadgeAward.
 *
 * @param {BadgeAward} badgeAward - The BadgeAward object.
 * @returns {EventTemplate} - The generated EventTemplate object.
 */
export function generateBadgeAwardEventTemplate({ a, p }: BadgeAward): EventTemplate {
  // Mandatory tags
  const tags: string[][] = [['a', a]]
  for (const _p of p) {
    tags.push(['p', ..._p])
  }

  // Construct the EventTemplate object
  const eventTemplate: EventTemplate = {
    content: '',
    created_at: Math.floor(Date.now() / 1000),
    kind: BadgeAwardKind,
    tags,
  }

  return eventTemplate
}

/**
 * Validates a badge award event.
 *
 * @param event - The event to validate.
 * @returns A boolean indicating whether the event is a valid badge award event.
 */
export function validateBadgeAwardEvent(event: Event): boolean {
  if (event.kind !== BadgeAwardKind) return false

  const requiredTags = ['a', 'p'] as const
  for (const tag of requiredTags) {
    if (!event.tags.find(([t]) => t == tag)) return false
  }

  return true
}

/**
 * Generates an EventTemplate based on the provided ProfileBadges.
 *
 * @param {ProfileBadges} profileBadges - The ProfileBadges object.
 * @returns {EventTemplate} - The generated EventTemplate object.
 */
export function generateProfileBadgesEventTemplate({ badges }: ProfileBadges): EventTemplate {
  // Mandatory tags
  const tags: string[][] = [['d', 'profile_badges']]

  // Append optional tags
  for (const badge of badges) {
    tags.push(['a', badge.a], ['e', ...badge.e])
  }

  // Construct the EventTemplate object
  const eventTemplate: EventTemplate = {
    content: '',
    created_at: Math.floor(Date.now() / 1000),
    kind: ProfileBadgesKind,
    tags,
  }

  return eventTemplate
}

/**
 * Validates a profile badges event.
 *
 * @param event - The event to validate.
 * @returns A boolean indicating whether the event is a valid profile badges event.
 */
export function validateProfileBadgesEvent(event: Event): boolean {
  if (event.kind !== ProfileBadgesKind) return false

  const requiredTags = ['d'] as const
  for (const tag of requiredTags) {
    if (!event.tags.find(([t]) => t == tag)) return false
  }

  return true
}