cinny/src/app/hooks/useUserNotes.ts

import { useCallback, useEffect, useState } from 'react';
import { MatrixClient } from 'matrix-js-sdk';
import { useMatrixClient } from './useMatrixClient';
import { useAccountDataCallback } from './useAccountDataCallback';

const NOTES_KEY = 'io.lotus.user_notes';
export const USER_NOTE_MAX_LENGTH = 500;

type UserNotesContent = Record<string, string>;

function readNotes(mx: MatrixClient): UserNotesContent {
  return (mx.getAccountData(NOTES_KEY as any)?.getContent() as UserNotesContent | undefined) ?? {};
}

export function useUserNotes(): {
  getNote: (userId: string) => string;
  setNote: (userId: string, note: string) => Promise<void>;
} {
  const mx = useMatrixClient();
  const [notes, setNotes] = useState<UserNotesContent>(() => readNotes(mx));

  useAccountDataCallback(
    mx,
    useCallback((evt) => {
      if (evt.getType() === NOTES_KEY) {
        setNotes(evt.getContent<UserNotesContent>() ?? {});
      }
    }, []),
  );

  useEffect(() => {
    setNotes(readNotes(mx));
  }, [mx]);

  const getNote = useCallback((userId: string) => notes[userId] ?? '', [notes]);

  const setNote = useCallback(
    async (userId: string, note: string) => {
      const current = readNotes(mx);
      const updated = { ...current };
      const trimmed = note.trim().slice(0, USER_NOTE_MAX_LENGTH);
      if (trimmed) {
        updated[userId] = trimmed;
      } else {
        delete updated[userId];
      }
      await (mx as any).setAccountData(NOTES_KEY, updated);
    },
    [mx],
  );

  return { getNote, setNote };
}