// Narrow browser protocol, inspired by letta-ai/letta-agent-sdk-react-chat.
// No SDK payload, tool arguments/results, or reasoning crosses this boundary.
export type ChatRow =
  | { kind: "user" | "assistant"; key: string; text: string; otid?: string }
  | { kind: "tool_call"; key: string; name: string; outcome: "pending" | "complete" | "failed" };
export type TurnStatus = "dispatching" | "running" | "stopping" | "completed" | "interrupted" | "failed" | "unknown";
export interface TurnReceipt {
  requestId: string;
  status: TurnStatus;
  createdAt: string;
  updatedAt: string;
  runIds: string[];
}
export interface WebConversation {
  id: string;
  title: string;
  createdAt: string;
  updatedAt: string;
  turn?: TurnReceipt;
}
export interface ChatSnapshot {
  conversation: WebConversation;
  rows: ChatRow[];
  model?: string;
  historyPending?: boolean;
  nextBefore?: string | null;
  hasMore?: boolean;
  runtime?: { online: boolean; processing: boolean; permissionMode: string };
}
export interface ChatContext { source: string; observedAt: string; excerpt: string }
export interface ChatSend { requestId: string; text: string; context?: ChatContext | undefined }
export function rowIdentity(row: ChatRow): string {
  return row.kind !== "tool_call" && row.otid ? `${row.kind}:otid:${row.otid}` : row.key;
}
export function mergeRows(previous: readonly ChatRow[], current: readonly ChatRow[]): ChatRow[] {
  const keys = new Set(current.map(rowIdentity));
  return [...previous.filter((row) => !keys.has(rowIdentity(row))), ...current];
}
export function isUnsettled(status: TurnStatus | undefined): boolean {
  return status !== undefined && !["completed", "interrupted", "failed"].includes(status);
}