import { simpleParser, ParsedMail, Attachment, HeaderValue, AddressObject } from 'mailparser';

export interface DecodedEmail {
  html: string | false;
  text: string | false;
  attachments: Attachment[];
  headers: Map<string, HeaderValue>;
  subject: string;
  from: string;
  to: string;
  date: Date;
}

function getAddressText(address: AddressObject | AddressObject[] | undefined): string {
  if (!address) return '';
  if (Array.isArray(address)) {
    return address.map(addr => addr.value?.[0]?.address || '').filter(Boolean).join(', ');
  }
  return address.value?.[0]?.address || '';
}

export async function decodeEmail(rawEmail: string): Promise<DecodedEmail> {
  try {
    const parsed = await simpleParser(rawEmail);
    
    return {
      html: parsed.html || false,
      text: parsed.text || false,
      attachments: parsed.attachments || [],
      headers: parsed.headers,
      subject: parsed.subject || '',
      from: getAddressText(parsed.from),
      to: getAddressText(parsed.to),
      date: parsed.date || new Date()
    };
  } catch (error) {
    console.error('Error decoding email:', error);
    throw new Error('Failed to decode email');
  }
}

export function cleanHtml(html: string): string {
  if (!html) return '';
  
  // Detect text direction from the content
  const hasRtlChars = /[\u0591-\u07FF\u200F\u202B\u202E\uFB1D-\uFDFD\uFE70-\uFEFC]/.test(html);
  const defaultDir = hasRtlChars ? 'rtl' : 'ltr';
  
  // Basic HTML cleaning while preserving structure
  const cleaned = html
    // Remove script and style tags
    .replace(/<script[^>]*>[\s\S]*?<\/script>/gi, '')
    .replace(/<style[^>]*>[\s\S]*?<\/style>/gi, '')
    // Remove meta tags
    .replace(/<meta[^>]*>/gi, '')
    // Remove head and title
    .replace(/<head[^>]*>[\s\S]*?<\/head>/gi, '')
    .replace(/<title[^>]*>[\s\S]*?<\/title>/gi, '')
    // Remove body tags
    .replace(/<body[^>]*>/gi, '')
    .replace(/<\/body>/gi, '')
    // Remove html tags
    .replace(/<html[^>]*>/gi, '')
    .replace(/<\/html>/gi, '')
    // Clean up whitespace
    .replace(/\s+/g, ' ')
    .trim();
  
  // Wrap in a div with the detected direction
  return `<div dir="${defaultDir}">${cleaned}</div>`;
}