sitegen/framework/meta/nextjs/resolvers/resolve-opengraph.ts

import type { Metadata, ResolvedMetadata } from "../types/metadata-interface";
import type {
  OpenGraph,
  OpenGraphType,
  ResolvedOpenGraph,
} from "../types/opengraph-types";
import type { FieldResolverWithMetadataBase } from "../types/resolvers";
import type { ResolvedTwitterMetadata, Twitter } from "../types/twitter-types";
import { resolveAsArrayOrUndefined } from "../generate/utils";
import { isStringOrURL, resolveUrl } from "./resolve-url";

const OgTypeFields = {
  article: ["authors", "tags"],
  song: ["albums", "musicians"],
  playlist: ["albums", "musicians"],
  radio: ["creators"],
  video: ["actors", "directors", "writers", "tags"],
  basic: [
    "emails",
    "phoneNumbers",
    "faxNumbers",
    "alternateLocale",
    "audio",
    "videos",
  ],
} as const;

function resolveImages(
  images: Twitter["images"],
  metadataBase: ResolvedMetadata["metadataBase"],
): NonNullable<ResolvedMetadata["twitter"]>["images"];
function resolveImages(
  images: OpenGraph["images"],
  metadataBase: ResolvedMetadata["metadataBase"],
): NonNullable<ResolvedMetadata["openGraph"]>["images"];
function resolveImages(
  images: OpenGraph["images"] | Twitter["images"],
  metadataBase: ResolvedMetadata["metadataBase"],
):
  | NonNullable<ResolvedMetadata["twitter"]>["images"]
  | NonNullable<ResolvedMetadata["openGraph"]>["images"] {
  const resolvedImages = resolveAsArrayOrUndefined(images);
  resolvedImages?.forEach((item, index, array) => {
    if (isStringOrURL(item)) {
      array[index] = {
        url: resolveUrl(item, metadataBase)!,
      };
    } else {
      // Update image descriptor url
      item.url = resolveUrl(item.url, metadataBase)!;
    }
  });
  return resolvedImages;
}

function getFieldsByOgType(ogType: OpenGraphType | undefined) {
  switch (ogType) {
    case "article":
    case "book":
      return OgTypeFields.article;
    case "music.song":
    case "music.album":
      return OgTypeFields.song;
    case "music.playlist":
      return OgTypeFields.playlist;
    case "music.radio_station":
      return OgTypeFields.radio;
    case "video.movie":
    case "video.episode":
      return OgTypeFields.video;
    default:
      return OgTypeFields.basic;
  }
}

export const resolveOpenGraph: FieldResolverWithMetadataBase<"openGraph"> = (
  openGraph: Metadata["openGraph"],
  metadataBase: ResolvedMetadata["metadataBase"],
) => {
  if (!openGraph) return null;

  const url = resolveUrl(openGraph.url, metadataBase);
  const resolved = { ...openGraph } as ResolvedOpenGraph;

  function assignProps(og: OpenGraph) {
    const ogType = og && "type" in og ? og.type : undefined;
    const keys = getFieldsByOgType(ogType);
    for (const k of keys) {
      const key = k as keyof ResolvedOpenGraph;
      if (key in og && key !== "url") {
        const value = og[key];
        if (value) {
          const arrayValue = resolveAsArrayOrUndefined(value); /// TODO: improve typing inferring
          (resolved as any)[key] = arrayValue;
        }
      }
    }

    resolved.images = resolveImages(og.images, metadataBase);
  }

  assignProps(openGraph);

  resolved.url = url;

  return resolved;
};

const TwitterBasicInfoKeys = [
  "site",
  "siteId",
  "creator",
  "creatorId",
  "description",
] as const;

export const resolveTwitter: FieldResolverWithMetadataBase<"twitter"> = (
  twitter,
  metadataBase,
) => {
  if (!twitter) return null;
  const resolved = {
    ...twitter,
    card: "card" in twitter ? twitter.card : "summary",
  } as ResolvedTwitterMetadata;
  for (const infoKey of TwitterBasicInfoKeys) {
    resolved[infoKey] = twitter[infoKey] || null;
  }
  resolved.images = resolveImages(twitter.images, metadataBase);

  if ("card" in resolved) {
    switch (resolved.card) {
      case "player": {
        resolved.players = resolveAsArrayOrUndefined(resolved.players) || [];
        break;
      }
      case "app": {
        resolved.app = resolved.app || {};
        break;
      }
      default:
        break;
    }
  }

  return resolved;
};