import { useEffect, useState } from 'react';
import { CallEmbed } from '../plugins/call';
import { nextSpeakerSet } from '../utils/speakerSet';
import { useCallMembers, useCallSession } from './useCall';
import { useCallJoined } from './useCallEmbed';

/**
 * Returns the set of Matrix user IDs currently speaking in the call, from the
 * fork's io.lotus.call_state reports ([lotus #2]).
 *
 * [Gitea #43] The fallback that scraped EC's rendered tiles (the speaking
 * ring's `::before` background) is gone: the bundled fork always reports call
 * state, and the host no longer reads the call frame's DOM.
 */
export const useCallSpeakers = (callEmbed: CallEmbed): Set<string> => {
  const [speakers, setSpeakers] = useState(new Set<string>());
  const callSession = useCallSession(callEmbed.room);
  const callMembers = useCallMembers(callSession);
  const joined = useCallJoined(callEmbed);

  // C-L5 — depend on a STABLE boolean, not the callMembers array (whose identity
  // changes on every membership change). The io.lotus.call_state subscription
  // below already tracks participants joining/leaving live.
  const hasCallMembers = callMembers.length > 0;

  useEffect(() => {
    if (!hasCallMembers || !joined) {
      setSpeakers(new Set<string>());
      return undefined;
    }

    const syncState = (): void => {
      // #32 — bail out of setState (and the re-render it causes) when the
      // derived set is unchanged from the previous one.
      setSpeakers((prev) => nextSpeakerSet(prev, callEmbed.getLotusParticipants() ?? []));
    };

    syncState();
    return callEmbed.onLotusCallState(syncState);
  }, [callEmbed, hasCallMembers, joined]);

  return speakers;
};

/**
 * Returns true when there is at least one REMOTE participant and every one of
 * them has their microphone muted, from the fork's io.lotus.call_state reports.
 */
export const useRemoteAllMuted = (callEmbed: CallEmbed | undefined): boolean => {
  const [muted, setMuted] = useState(false);

  useEffect(() => {
    if (!callEmbed) return undefined;

    const localUserId = callEmbed.room.client?.getUserId() ?? '';

    const syncState = (): void => {
      const remote = (callEmbed.getLotusParticipants() ?? []).filter(
        (p) => p.userId !== localUserId,
      );
      setMuted(remote.length > 0 && remote.every((p) => !p.audioEnabled));
    };

    syncState();
    return callEmbed.onLotusCallState(syncState);
  }, [callEmbed]);

  return muted;
};