'use client';

import DOMPurify from 'dompurify';

export interface ParsedEmail {
  subject: string | null;
  from: string | null;
  to: string | null;
  cc: string | null;
  bcc: string | null;
  date: Date | null;
  html: string | null;
  text: string | null;
  attachments: Array<{
    filename: string;
    contentType: string;
    size: number;
  }>;
  headers: Record<string, any>;
}

export async function decodeEmail(emailContent: string): Promise<ParsedEmail> {
  try {
    // Ensure the email content is properly formatted
    const formattedContent = emailContent?.trim();
    if (!formattedContent) {
      return {
        subject: null,
        from: null,
        to: null,
        cc: null,
        bcc: null,
        date: null,
        html: null,
        text: 'No content available',
        attachments: [],
        headers: {}
      };
    }

    const response = await fetch('/api/parse-email', {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({ email: formattedContent }),
    });

    const data = await response.json();

    if (!response.ok) {
      console.error('API Error:', data);
      return {
        subject: null,
        from: null,
        to: null,
        cc: null,
        bcc: null,
        date: null,
        html: null,
        text: data.error || 'Failed to parse email',
        attachments: [],
        headers: {}
      };
    }

    // If we have a successful response but no content
    if (!data.html && !data.text) {
      return {
        ...data,
        date: data.date ? new Date(data.date) : null,
        html: null,
        text: 'No content available',
        attachments: data.attachments || [],
        headers: data.headers || {}
      };
    }

    return {
      ...data,
      date: data.date ? new Date(data.date) : null,
      text: data.text || null,
      html: data.html || null,
      attachments: data.attachments || [],
      headers: data.headers || {}
    };
  } catch (error) {
    console.error('Error parsing email:', error);
    return {
      subject: null,
      from: null,
      to: null,
      cc: null,
      bcc: null,
      date: null,
      html: null,
      text: 'Error parsing email content',
      attachments: [],
      headers: {}
    };
  }
}

export function cleanHtml(html: string): string {
  try {
    // Enhanced configuration to preserve more HTML elements for complex emails
    return DOMPurify.sanitize(html, {
      ADD_TAGS: ['style', 'meta', 'link', 'table', 'thead', 'tbody', 'tr', 'td', 'th', 'hr', 'font', 'div', 'span', 'a', 'img', 'b', 'strong', 'i', 'em', 'u', 'br', 'p', 'ul', 'ol', 'li', 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'blockquote', 'pre', 'code', 'center', 'section', 'header', 'footer', 'article', 'nav'],
      ADD_ATTR: ['*', 'colspan', 'rowspan', 'cellpadding', 'cellspacing', 'border', 'bgcolor', 'width', 'height', 'align', 'valign', 'class', 'id', 'style', 'color', 'face', 'size', 'background', 'src', 'href', 'target', 'rel', 'alt', 'title', 'name'],
      ALLOW_UNKNOWN_PROTOCOLS: true,
      WHOLE_DOCUMENT: true,
      KEEP_CONTENT: true,
      RETURN_DOM: false,
      FORBID_TAGS: ['script', 'iframe', 'object', 'embed', 'form', 'input', 'button', 'select', 'option', 'textarea', 'canvas', 'video', 'audio'],
      FORBID_ATTR: ['onerror', 'onload', 'onclick', 'onmouseover', 'onmouseout', 'onchange', 'onsubmit']
    });
  } catch (error) {
    console.error('Error cleaning HTML:', error);
    return html;
  }
}