123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133
import { merge } from "../core/utils.ts";
import type { Page, Site } from "../core.ts";import type { HTMLDocument } from "../deps/dom.ts";
export interface Options {  /** The list extensions this plugin applies to */  extensions: string[];
  /** The key name for the transformations definitions */  name: string;
  /** Default values */  defaults: Partial<MetaData>;}
export interface MetaData {  /** The name of the site */  site: string;
  /** The title of the page */  title: string;
  /** The page language */  lang: string;
  /** The description of the page */  description: string;
  /** The image of the page */  image: string;
  /** The icon of the site */  icon: string;
  /** The page keywords */  keywords: string[];
  /** The twitter username */  twitter: string;
  /** The color theme */  color: string;}
const defaults: Options = {  extensions: [".html"],  name: "metas",  defaults: {},};
/** A plugin to insert meta tags for SEO and social media */export default function (userOptions?: Partial<Options>) {  const options = merge(defaults, userOptions);
  return (site: Site) => {    site.process(options.extensions, metas);
    function metas(page: Page) {      const pageMetas = page.data[options.name] as MetaData | undefined;
      if (!pageMetas || !page.document) {        return;      }
      const { document } = page;      const metas: Partial<MetaData> = {        ...options.defaults,        ...pageMetas,      };
      const url = site.url(page.data.url as string, true);      const icon = metas.icon ? site.url(metas.icon, true) : undefined;      const image = metas.image ? site.url(metas.image, true) : undefined;
      // Open graph      addMeta(document, "property", "og:type", "website");      addMeta(document, "property", "og:site_name", metas.site);      addMeta(document, "property", "og:locale", metas.lang);      addMeta(document, "property", "og:title", metas.title, 65);      addMeta(document, "property", "og:description", metas.description, 155);      addMeta(document, "property", "og:url", url);      addMeta(document, "property", "og:image", image || icon);
      // Twitter cards      addMeta(document, "name", "twitter:title", metas.title, 65);      addMeta(document, "name", "twitter:description", metas.description, 200);      addMeta(        document,        "name",        "twitter:card",        image ? "summary_large_image" : "summary",      );      addMeta(document, "name", "twitter:image", image || icon);      addMeta(document, "name", "twitter:site", metas.twitter);
      // Schema.org      addMeta(document, "itemprop", "name", metas.title);      addMeta(document, "itemprop", "description", metas.description, 155);      addMeta(document, "itemprop", "image", image || icon);
      // SEO      addMeta(document, "name", "description", metas.description, 155);      addMeta(document, "name", "keywords", metas.keywords?.join(", "));
      // Misc      addMeta(document, "name", "theme-color", metas.color);    }  };}
function addMeta(  document: HTMLDocument,  propName: string,  propValue: string,  content?: string,  limit?: number,) {  if (!content) {    return;  }
  if (limit && content.length > limit) {    content = content.substr(0, limit - 3) + "...";  }
  const meta = document.createElement("meta");  meta.setAttribute(propName, propValue);  meta.setAttribute("content", content);  document.head.appendChild(meta);  document.head.appendChild(document.createTextNode("\n"));}