import type { CitationSource } from './CitationChip/index.js';
/** Author of a chat message. */
export type ChatRole = 'user' | 'assistant' | 'system';
/**
 * Lifecycle of a message. `streaming` drives the live-rendering affordances
 * (markdown tail repair, cursor, deferred screen-reader announcement);
 * `error` / `aborted` switch the message to its failure presentation.
 * A message without a status counts as `complete`.
 */
export type ChatMessageStatus = 'streaming' | 'complete' | 'error' | 'aborted';
/**
 * One renderable segment of a message. Mirrors the shape of modern
 * model/tool transcripts: interleaved text, reasoning, tool calls, sources
 * and attachments — rendered in order by the ChatMessage component.
 */
export type ChatMessagePart = 
/** Markdown text, rendered through StreamingMarkdown. */
{
    type: 'text';
    text: string;
}
/** Model reasoning. Collapsed, tertiary presentation; `durationMs` feeds the "Thought for Xs" label. */
 | {
    type: 'reasoning';
    text: string;
    durationMs?: number;
}
/** A tool invocation with its lifecycle state. Rendered as a ToolCallCard by default; override via `partRenderers`. */
 | {
    type: 'tool-call';
    id: string;
    name: string;
    state: 'pending' | 'running' | 'complete' | 'error';
    input?: unknown;
    output?: unknown;
    errorMessage?: string;
}
/** A cited source. Same shape as CitationSource — also feeds StreamingMarkdown's `sources` for `[id]` markers. */
 | ({
    type: 'source';
} & CitationSource)
/**
 * A file attached to the message. `url` is only ever rendered as a
 * policy-checked download link (never as an inline image/iframe) — LLM- or
 * server-supplied URLs are untrusted input.
 */
 | {
    type: 'attachment';
    name: string;
    mimeType: string;
    size?: number;
    url?: string;
}
/** Declarative A2UI payload (P4). Validated fail-loud by A2UIView; ignored by default renderers until then. */
 | {
    type: 'a2ui';
    payload: unknown;
};
/** The `tool-call` member of {@link ChatMessagePart} — the prop shape of ToolCallCard. */
export type ChatToolCallPart = Extract<ChatMessagePart, {
    type: 'tool-call';
}>;
/** The `reasoning` member of {@link ChatMessagePart} — the prop shape of ReasoningDisclosure. */
export type ChatReasoningPart = Extract<ChatMessagePart, {
    type: 'reasoning';
}>;
/**
 * One message in a conversation. Named `ChatMessageData` because the value
 * export `ChatMessage` is the component that renders it.
 */
export interface ChatMessageData {
    /** Stable unique id — keyed `{#each}` identity, never an array index. */
    id: string;
    role: ChatRole;
    /** Ordered renderable segments. A plain text answer is `[{ type: 'text', text }]`. */
    parts: ChatMessagePart[];
    createdAt?: Date;
    /** Omitted counts as `complete`. */
    status?: ChatMessageStatus;
    /** Consumer-defined extras (model name, token counts, …). Not rendered by defaults. */
    metadata?: Record<string, unknown>;
}