export type ChatRole = 'user' | 'assistant' | 'system' | 'tool'

export type ChatMessageStatus = 'streaming' | 'complete' | 'error'

export type ChatMessageKind = 'text' | 'tool' | 'status'

/**
 * A reference attachment already persisted on a message (server shape). Rendered
 * as a chip/thumbnail on the message that carries it.
 */
export interface ChatMessageAttachment {
  id: string
  /** Asset url (image thumbnails / download link); may be null while pending. */
  fileUrl: string | null
  filename: string
  contentType: string
}

export interface ChatMessageData {
  id: string
  role: ChatRole
  content: string
  /** Display name for the author (defaults derived from role). */
  author?: string
  timestamp?: string | number | Date
  /** `streaming` shows a live indicator; `error` styles the bubble as failed. */
  status?: ChatMessageStatus
  /** `tool`/`status` render as compact system rows rather than chat bubbles. */
  kind?: ChatMessageKind
  /** Name of the tool when kind === 'tool'. */
  toolName?: string
  /** Reference attachments carried by this message (rendered as chips). */
  attachments?: ChatMessageAttachment[]
}

/**
 * A composer-side pending attachment. The APP owns upload state and feeds these
 * down as a controlled prop; the composer renders them as chips with progress.
 */
export interface PendingAttachment {
  id: string
  name: string
  /**
   * `queued` = parked client-side, waiting for a document to land on (a brand-new
   * deck has no document until the first turn creates it). It is NOT actively
   * uploading — surfacing it as `uploading` at 0% reads as a stuck upload.
   */
  status: 'queued' | 'uploading' | 'ready' | 'error'
  /** Upload progress 0..1 while `status === 'uploading'`. */
  progress?: number
  /** Object/asset url for an image preview thumbnail. */
  thumbnailUrl?: string
  sizeBytes?: number
  /** Human-readable failure reason shown on `status === 'error'` chips. */
  error?: string
}