import type { MessageRef, RichBlock, ActionElement, DurableHooks } from './types.js';
export interface MutableRegion {
    /** Replace the region's content. No-op once the stream commits past this region. */
    update(text: string): void;
}
export interface OutputStream {
    /** Emit committed assistant text — a hard boundary for aggregation. */
    emitText(text: string): void;
    /** Open a fresh mutable region, returning a handle for updates.
     *  The region is sealed when emitText, openMutable, or postInteractive is called next. */
    openMutable(text: string): MutableRegion;
    /** Post an independent interactive message (buttons, actions). Resets the internal cursor. */
    postInteractive(text: string, opts?: {
        richBlocks?: RichBlock[];
        actions?: ActionElement[];
    }): Promise<MessageRef | null>;
    /** Await all queued operations and surface any captured errors. */
    flush(): Promise<void>;
    /** All MessageRefs posted by this stream, in order. */
    getRefs(): MessageRef[];
    /** The first MessageRef posted (the parent / root of the thread). */
    getParentRef(): MessageRef | null;
}
export interface OpenOutputStreamOpts {
    threadId?: string | null;
    /** Anchor message to thread under. For composite (multi-platform) destinations this may carry
     *  `parts[]` (per-platform sub-refs); CompositeAdapter resolves the right per-platform anchor for
     *  each sub-stream so a platform never receives another platform's (incompatible) messageId.
     *  Single adapters ignore this and rely on `threadId`. */
    anchorRef?: MessageRef | null;
    onMessagePosted?: ((ref: MessageRef) => void) | null;
    durable?: DurableHooks | null;
}