export interface ExtractedOpenGraph {
  title?: string;
  description?: string;
  publishedDate?: string;
  author?: string;
  siteName?: string;
}

/**
 * Internal helper to query meta content by property or name attribute.
 */
function getMetaContent(doc: Document, selectors: string[]): string | undefined {
  for (const selector of selectors) {
    const element = doc.querySelector(selector);
    if (element) {
      const content = element.getAttribute("content");
      if (content && content.trim()) {
        return content.trim();
      }
    }
  }
  return undefined;
}

/**
 * Extracts Open Graph, Twitter, and standard HTML meta tags from the document.
 */
export function extractOpenGraph(doc: Document): ExtractedOpenGraph {
  const title = getMetaContent(doc, [
    'meta[property="og:title"]',
    'meta[name="twitter:title"]',
    'meta[name="title"]',
  ]);

  const description = getMetaContent(doc, [
    'meta[property="og:description"]',
    'meta[name="twitter:description"]',
    'meta[name="description"]',
  ]);

  const publishedDate = getMetaContent(doc, [
    'meta[property="article:published_time"]',
    'meta[property="og:article:published_time"]',
    'meta[property="article:modified_time"]',
    'meta[name="pubdate"]',
    'meta[name="dc.date"]',
    'meta[name="date"]',
  ]);

  const author = getMetaContent(doc, [
    'meta[name="author"]',
    'meta[property="article:author"]',
    'meta[property="og:article:author"]',
    'meta[name="twitter:creator"]',
  ]);

  const siteName = getMetaContent(doc, [
    'meta[property="og:site_name"]',
    'meta[name="application-name"]',
  ]);

  return {
    title,
    description,
    publishedDate,
    author,
    siteName,
  };
}

export interface ExtractedOpenGraph {
  title?: string;
  description?: string;
  publishedDate?: string;
  author?: string;
  siteName?: string;
}

/**
 * Internal helper to query meta content by property or name attribute.
 */
function getMetaContent(doc: Document, selectors: string[]): string | undefined {
  for (const selector of selectors) {
    const element = doc.querySelector(selector);
    if (element) {
      const content = element.getAttribute("content");
      if (content && content.trim()) {
        return content.trim();
      }
    }
  }
  return undefined;
}

/**
 * Extracts Open Graph, Twitter, and standard HTML meta tags from the document.
 */
export function extractOpenGraph(doc: Document): ExtractedOpenGraph {
  const title = getMetaContent(doc, [
    'meta[property="og:title"]',
    'meta[name="twitter:title"]',
    'meta[name="title"]',
  ]);

  const description = getMetaContent(doc, [
    'meta[property="og:description"]',
    'meta[name="twitter:description"]',
    'meta[name="description"]',
  ]);

  const publishedDate = getMetaContent(doc, [
    'meta[property="article:published_time"]',
    'meta[property="og:article:published_time"]',
    'meta[property="article:modified_time"]',
    'meta[name="pubdate"]',
    'meta[name="dc.date"]',
    'meta[name="date"]',
  ]);

  const author = getMetaContent(doc, [
    'meta[name="author"]',
    'meta[property="article:author"]',
    'meta[property="og:article:author"]',
    'meta[name="twitter:creator"]',
  ]);

  const siteName = getMetaContent(doc, [
    'meta[property="og:site_name"]',
    'meta[name="application-name"]',
  ]);

  return {
    title,
    description,
    publishedDate,
    author,
    siteName,
  };
}