gallery.badmanners.xyz/src/pages/api/export-story/[...slug].ts

import type { APIRoute, GetStaticPaths } from "astro";
import { getCollection, type CollectionEntry, getEntries } from "astro:content";
import type { Website } from "../../../content/config";
import { t, type Lang } from "../../../i18n";
import { formatCopyrightedCharacters } from "../../../utils/format_copyrighted_characters";
import { markdownToBbcode } from "../../../utils/markdown_to_bbcode";
import { getUsernameForLang } from "../../../utils/get_username_for_lang";
import { isAnonymousUser } from "../../../utils/is_anonymous_user";

interface ExportWebsiteInfo {
  website: Website;
  exportFormat: "bbcode" | "markdown";
}

const WEBSITE_LIST = [
  { website: "eka", exportFormat: "bbcode" },
  { website: "furaffinity", exportFormat: "bbcode" },
  { website: "inkbunny", exportFormat: "bbcode" },
  { website: "sofurry", exportFormat: "bbcode" },
  { website: "weasyl", exportFormat: "markdown" },
] as const satisfies ExportWebsiteInfo[];

type ExportWebsiteName = typeof WEBSITE_LIST extends ReadonlyArray<{ website: infer K }> ? K : never;

function getUsernameForWebsite(user: CollectionEntry<"users">, website: Website): string {
  const link = user.data.links[website];
  if (link && "username" in link && link.username) {
    return link.username;
  }
  throw new Error(`Cannot get "${website}" username for user "${user.id}"`);
}

function isPreferredWebsite(user: CollectionEntry<"users">, website: Website): boolean {
  const { preferredLink } = user.data;
  return !preferredLink || preferredLink == website;
}

function getLinkForUser(user: CollectionEntry<"users">, website: ExportWebsiteName, lang: Lang): string {
  const { links, preferredLink } = user.data;
  switch (website) {
    case "eka":
      if ("eka" in links) {
        return `:icon${getUsernameForWebsite(user, "eka")}:`;
      }
      break;
    case "furaffinity":
      if ("furaffinity" in links) {
        return `:icon${getUsernameForWebsite(user, "furaffinity")}:`;
      }
      break;
    case "weasyl":
      if ("weasyl" in links) {
        return `<!~${getUsernameForWebsite(user, "weasyl").replaceAll(" ", "")}>`;
      } else if (isPreferredWebsite(user, "furaffinity")) {
        return `<fa:${getUsernameForWebsite(user, "furaffinity").replaceAll("_", "")}>`;
      } else if (isPreferredWebsite(user, "inkbunny")) {
        return `<ib:${getUsernameForWebsite(user, "inkbunny")}>`;
      } else if (isPreferredWebsite(user, "sofurry")) {
        return `<sf:${getUsernameForWebsite(user, "sofurry")}>`;
      }
      break;
    case "inkbunny":
      if ("inkbunny" in links) {
        return `[iconname]${getUsernameForWebsite(user, "inkbunny")}[/iconname]`;
      } else if (isPreferredWebsite(user, "furaffinity")) {
        return `[fa]${getUsernameForWebsite(user, "furaffinity")}[/fa]`;
      } else if (isPreferredWebsite(user, "sofurry")) {
        return `[sf]${getUsernameForWebsite(user, "sofurry")}[/sf]`;
      } else if (isPreferredWebsite(user, "weasyl")) {
        return `[weasyl]${getUsernameForWebsite(user, "weasyl")}[/weasyl]`;
      }
      break;
    case "sofurry":
      if ("sofurry" in links) {
        return `:icon${getUsernameForWebsite(user, "sofurry")}:`;
      } else if (isPreferredWebsite(user, "furaffinity")) {
        return `fa!${getUsernameForWebsite(user, "furaffinity")}`;
      } else if (isPreferredWebsite(user, "inkbunny")) {
        return `ib!${getUsernameForWebsite(user, "inkbunny")}`;
      }
      break;
    default:
      const unknown: never = website;
      throw new Error(`Unhandled export website "${unknown}"`);
  }
  if (preferredLink) {
    const preferred = links[preferredLink]!;
    return `[${getUsernameForLang(user, lang)}](${preferred.link})`;
  }
  throw new Error(
    `No matching "${website}" link for user "${user.id}" (consider setting their "preferredLink" property)`,
  );
}

type Props = {
  story: CollectionEntry<"stories">;
};

type Params = {
  slug: CollectionEntry<"stories">["slug"];
};

export const getStaticPaths: GetStaticPaths = async () => {
  if (import.meta.env.PROD) {
    return [];
  }
  return (await getCollection("stories")).map((story) => ({
    params: { slug: story.slug } satisfies Params,
    props: { story } satisfies Props,
  }));
};

export const GET: APIRoute<Props, Params> = async ({ props: { story }, site }) => {
  const { lang } = story.data;
  const copyrightedCharacters = await formatCopyrightedCharacters(story.data.copyrightedCharacters);
  const authorsList = await getEntries(story.data.authors);
  const commissionersList = story.data.commissioner && (await getEntries(story.data.commissioner));
  const requestersList = story.data.requester && (await getEntries(story.data.requester));

  const description = Object.fromEntries(
    WEBSITE_LIST.map<[ExportWebsiteName, string]>(({ website, exportFormat }) => {
      const u = (user: CollectionEntry<"users">) =>
        isAnonymousUser(user) ? getUsernameForLang(user, lang) : getLinkForUser(user, website, lang);
      const storyDescription = (
        [
          story.data.description,
          `*${t(lang, "story/warnings", story.data.wordCount, story.data.contentWarning)}*`,
          t(
            lang,
            "export_story/authors",
            authorsList.map((author) => u(author)),
          ),
          requestersList &&
            t(
              lang,
              "export_story/request_for",
              requestersList.map((requester) => u(requester)),
            ),
          commissionersList &&
            t(
              lang,
              "export_story/commissioned_by",
              commissionersList.map((commissioner) => u(commissioner)),
            ),
          ...copyrightedCharacters.map(([user, characterList]) =>
            characterList[0] == ""
              ? t(lang, "characters/all_characters_are_copyrighted_by", u(user))
              : t(lang, "characters/characters_are_copyrighted_by", u(user), characterList),
          ),
        ].filter((data) => data) as string[]
      )
        .join("\n\n")
        .replaceAll(
          /\[([^\]]+)\]\((\/[^\)]+)\)/g,
          (_, group1, group2) => `[${group1}](${new URL(group2, site).toString()})`,
        );
      switch (exportFormat) {
        case "bbcode":
          return [website, markdownToBbcode(storyDescription).replaceAll(/\n\n\n+/g, "\n\n")];
        case "markdown":
          return [website, storyDescription.replaceAll(/\n\n\n+/g, "\n\n").trim()];
        default:
          const unknown: never = exportFormat;
          throw new Error(`Unknown export format "${unknown}"`);
      }
    }),
  );

  const storyHeader =
    `${story.data.title}\n` +
    `${t(
      lang,
      "story/authors",
      authorsList.map((author) => getUsernameForLang(author, lang)),
    )}\n` +
    (requestersList
      ? `${t(
          lang,
          "story/requested_by",
          requestersList.map((requester) => getUsernameForLang(requester, lang)),
        )}\n`
      : "") +
    (commissionersList
      ? `${t(
          lang,
          "story/commissioned_by",
          commissionersList.map((commissioner) => getUsernameForLang(commissioner, lang)),
        )}\n`
      : "");

  const storyText = `${storyHeader}\n===\n\n${story.body.replaceAll(/\\([=*])/g, "$1")}`
    .replaceAll(/\n\n\n+/g, "\n\n")
    .trim();

  return new Response(
    JSON.stringify({
      story: storyText,
      description,
      thumbnail: story.data.thumbnail ? story.data.thumbnail.src : null,
    }),
    { headers: { "Content-Type": "application/json; charset=utf-8" } },
  );
};