import { join } from "node:path";
import type { APIRoute } from "astro";
import { stringify } from "yaml";
import type { AstroPostEntry } from "../../content.config";
import { getPosts } from "../../utils/getPost";

export async function getStaticPaths() {
  const blogEntries = await getPosts();
  return blogEntries.map((entry) => ({
    params: { id: entry.id },
    props: { entry },
  }));
}

export const GET: APIRoute<{ entry: AstroPostEntry }> = async ({
  props,
  url,
}) => {
  const md = props.entry.body ?? "";

  // ローカル画像参照箇所をフルパスに変換
  const localImagePaths =
    (props.entry.rendered?.metadata?.localImagePaths as string[] | undefined) ??
    [];
  const localPathsMap = new Map(
    localImagePaths.map((path) => {
      const localFullPath = join(props.entry.filePath ?? "", path).replace(
        "src/public",
        "",
      );
      const remoteUrl = new URL(localFullPath, url);
      return [path, remoteUrl.toString()];
    }),
  );
  const replaced = md.replace(
    /!\[([^\]]*)\]\(([^)]+)\)/g,
    (match, alt, path) => {
      const replacedPath = localPathsMap.get(path);
      if (replacedPath) {
        return `![${alt}](${replacedPath})`;
      }
      return match;
    },
  );

  // frontmatterをyamlに変換して先頭に結合
  const frontmatter = stringify(props.entry.rendered?.metadata?.frontmatter);
  const joined = `---\n${frontmatter}---\n${replaced}`;

  return new Response(joined, {
    headers: {
      "Content-Type": "text/markdown; charset=utf-8",
      "Access-Control-Allow-Origin": "*",
    },
  });
};