/** Parsed at:// URI. */
export interface AtUri {
  did: string
  collection: string
  rkey: string
}

/** site.standard.publication record value. */
export interface PublicationRecord {
  $type: 'site.standard.publication'
  url: string
  name: string
  description?: string
  /**
   * Declared as a blob, but records are third-party data: publishers in the
   * wild also put a plain path string here. Read it through `isBlobRef`.
   */
  icon?: unknown
}

/** site.standard.document record value. */
export interface DocumentRecord {
  $type: 'site.standard.document'
  site: string
  title: string
  publishedAt: string
  path?: string
  description?: string
  /**
   * Structured body (an open union of publishing-tool formats). Only its
   * presence matters to us: readers render in-app from `content`, not from
   * plain `textContent`.
   */
  content?: unknown
}

export interface BlobRef {
  $type: 'blob'
  ref: { $link: string }
  mimeType: string
  size: number
}

/** What we know about the publication behind a tab's page. */
export interface PubInfo {
  uri: string
  did: string
  handle?: string
  pds: string
  record: PublicationRecord
  iconUrl?: string
  /** Confirmed via .well-known lookup at the publication's URL. */
  verified: boolean
}

export interface DocInfo {
  uri: string
  record: DocumentRecord
}

/**
 * Why detection could not produce a definite answer. Distinct from "no
 * publication found": with an error set, pub/doc are unknown, not absent.
 */
export type DetectionError = 'offline' | 'fetch-failed'

/** Per-tab detection result, held by the background worker. */
export interface PageState {
  url: string
  fetchedAt: number
  pub?: PubInfo
  doc?: DocInfo
  /** Rkey of our subscription record, if subscribed. Null = known unsubscribed, undefined = unknown (e.g. logged out). */
  subscriptionRkey?: string | null
  /**
   * The signed-in account blocks the DID this publication belongs to.
   * Undefined = unknown (signed out, or the block list could not be read);
   * a block is only ever asserted, never guessed.
   */
  blocked?: boolean
  /** Set when detection itself failed rather than finding nothing. */
  error?: DetectionError
}

export interface SessionInfo {
  did: string
  handle?: string
  /** Avatar blob URL on the account's PDS; absent when there is none. */
  avatarUrl?: string
}

/**
 * What the worker answers a `follows` message with. Null means the question
 * has no answer — signed out, or the walk failed — which every caller draws as
 * nothing rather than as "you follow nobody".
 */
export interface FollowSet {
  /** Whose follows these are. The account can change between ask and answer. */
  did: string
  dids: string[]
  /** The walk stopped at its cap, so absence from `dids` is not a "no". */
  truncated: boolean
}

/** Messages between content script / popup and the background worker. */
export type Msg =
  | { type: 'page-hints'; pubHint?: string; docHint?: string }
  | { type: 'get-state'; tabId: number; refresh?: boolean }
  | { type: 'signin'; handle: string }
  | { type: 'follows'; refresh?: boolean }
  /** Dev channel only: forget every cached read. Answers `{dropped}`. */
  | { type: 'drop-caches' }

/**
 * Messages from the worker to the offscreen document that hosts the OAuth
 * client. `target` routes them: the worker's listener ignores these, and the
 * offscreen listener handles nothing else.
 */
export type OffscreenMsg =
  | { target: 'offscreen'; type: 'oauth-authorize'; handle: string }
  | { target: 'offscreen'; type: 'oauth-callback'; url: string }
  | { target: 'offscreen'; type: 'oauth-revoke'; sub: string }