import { useState, useEffect, useCallback } from 'react';
import { createMMKV } from 'react-native-mmkv';
import { localFileRegistry } from '../services/localFileRegistry';
import { safDirectory } from '../services/safDirectory';
import { useDeviceFiles } from './useDeviceFiles';

const syncStateStorage = createMMKV({ id: 'vaultdrop-sync-state' });

export function getIsSyncing(): boolean {
  return syncStateStorage.getString('is_syncing') === 'true';
}

export function setIsSyncing(value: boolean) {
  syncStateStorage.set('is_syncing', value ? 'true' : 'false');
}

export function useSyncQueue() {
  const [pendingCount, setPendingCount] = useState(0);
  const [isSyncing, setIsSyncingState] = useState(() => getIsSyncing());
  const { folders } = useDeviceFiles();

  const refresh = useCallback(() => {
    const allFolders = safDirectory.getAll();
    const syncFolderIds = new Set(
      allFolders.filter((f) => f.syncMode !== 'none').map((f) => f.id)
    );

    if (syncFolderIds.size === 0) {
      setPendingCount(0);
      setIsSyncingState(getIsSyncing());
      return;
    }

    const registry = localFileRegistry.getAll();
    let count = 0;
    for (const entry of registry) {
      if (entry.backendFileId) continue;
      if (entry.syncStatus !== 'local') continue;
      if (entry.folderId && !syncFolderIds.has(entry.folderId)) continue;
      count++;
    }

    setPendingCount(count);
    setIsSyncingState(getIsSyncing());
  }, []);

  useEffect(() => {
    refresh();
    const interval = setInterval(refresh, 5000);
    return () => clearInterval(interval);
  }, [refresh]);

  return { pendingCount, isSyncing, refresh };
}