cinny/src/app/utils/scheduledMessages.ts

import { IContent, MatrixClient, Method } from 'matrix-js-sdk';

/**
 * Schedule a message via MSC4140 (delayed messages).
 * @param mx - Matrix client instance
 * @param roomId - The room to send the message in
 * @param content - The message event content
 * @param sendAtMs - Unix timestamp (ms) when the message should be sent
 * @returns The delay_id returned by the server (use to cancel/restart)
 */
export async function scheduleMessage(
  mx: MatrixClient,
  roomId: string,
  content: IContent,
  sendAtMs: number,
): Promise<string> {
  const delayMs = Math.max(1000, Math.round(sendAtMs - Date.now()));
  const txnId = `sched_${Date.now()}_${Math.random().toString(36).slice(2)}`;
  // Use the path relative to the MSC4140 prefix — authedRequest prepends prefix to path.
  const path = `/rooms/${encodeURIComponent(roomId)}/send/m.room.message/${txnId}`;
  const res = (await mx.http.authedRequest(Method.Put, path, { delay: delayMs }, content, {
    prefix: '/_matrix/client/unstable/org.matrix.msc4140',
  })) as { delay_id: string };
  return res.delay_id;
}

/**
 * Cancel a scheduled message via MSC4140.
 * @param mx - Matrix client instance
 * @param delayId - The delay_id from scheduleMessage
 */
export async function cancelScheduledMessage(mx: MatrixClient, delayId: string): Promise<void> {
  const path = `/delayed_events/${encodeURIComponent(delayId)}`;
  await mx.http.authedRequest(
    Method.Post,
    path,
    undefined,
    { action: 'cancel' },
    {
      prefix: '/_matrix/client/unstable/org.matrix.msc4140',
    },
  );
}

export async function restartScheduledMessage(mx: MatrixClient, delayId: string): Promise<void> {
  const path = `/delayed_events/${encodeURIComponent(delayId)}`;
  await mx.http.authedRequest(
    Method.Post,
    path,
    undefined,
    { action: 'restart' },
    {
      prefix: '/_matrix/client/unstable/org.matrix.msc4140',
    },
  );
}