/**
 * Change the current folder and load emails from that folder
 */
const changeFolder = async (folder: string, accountId?: string) => {
  console.log(`Changing folder to ${folder} for account ${accountId || 'default'}`);
  try {
    // Reset selected email
    setSelectedEmail(null);
    setSelectedEmailIds([]);
    
    // Record the new folder
    setCurrentFolder(folder);
    
    // Reset search query when changing folders
    setSearchQuery('');
    
    // Reset to page 1
    setPage(1);
    
    // Clear existing emails before loading new ones to prevent UI flicker
    setEmails([]);
    
    // Show loading state
    setIsLoading(true);
    
    // Load emails for the new folder with a deliberate delay to allow state to update
    await new Promise(resolve => setTimeout(resolve, 100));
    await loadEmails(folder, 1, 20, accountId);
  } catch (error) {
    console.error(`Error changing to folder ${folder}:`, error);
    setError(`Failed to load emails from ${folder}: ${error instanceof Error ? error.message : 'Unknown error'}`);
  } finally {
    setIsLoading(false);
  }
};

/**
 * Load emails for the current folder
 */
const loadEmails = async (
  folderOverride?: string, 
  pageOverride?: number,
  perPageOverride?: number,
  accountIdOverride?: string
) => {
  const folderToUse = folderOverride || currentFolder;
  const pageToUse = pageOverride || page;
  const perPageToUse = perPageOverride || perPage;
  const accountIdToUse = accountIdOverride !== undefined ? accountIdOverride : 
                         folderToUse.includes(':') ? folderToUse.split(':')[0] : undefined;
  
  console.log(`Loading emails: folder=${folderToUse}, page=${pageToUse}, accountId=${accountIdToUse || 'default'}`);
  
  try {
    setIsLoading(true);
    setError('');
    
    // Construct the API URL with a unique timestamp to prevent caching
    let url = `/api/courrier/emails?folder=${encodeURIComponent(folderToUse)}&page=${pageToUse}&perPage=${perPageToUse}`;
    
    // Add accountId parameter if specified
    if (accountIdToUse) {
      url += `&accountId=${encodeURIComponent(accountIdToUse)}`;
    }
    
    // Add cache-busting timestamp
    url += `&_t=${Date.now()}`;
    
    console.log(`Fetching emails from API: ${url}`);
    const response = await fetch(url);
    
    if (!response.ok) {
      let errorText;
      try {
        const errorData = await response.json();
        errorText = errorData.error || `Server error: ${response.status}`;
      } catch {
        errorText = `HTTP error: ${response.status}`;
      }
      throw new Error(errorText);
    }
    
    const data = await response.json();
    
    if (pageOverride === 1 || !pageOverride) {
      // Replace emails when loading first page
      setEmails(data.emails);
    } else {
      // Append emails when loading subsequent pages
      setEmails(prev => [...prev, ...data.emails]);
    }
    
    // Update pagination info
    setTotalPages(data.totalPages);
    setMailboxes(data.mailboxes || []);
    
    return data;
  } catch (error) {
    console.error('Error loading emails:', error);
    setError(`Failed to load emails: ${error instanceof Error ? error.message : 'Unknown error'}`);
    return null;
  } finally {
    setIsLoading(false);
  }
};