import { defineConfig } from "blume";
import { custom, filesystem } from "blume/sources";
import { githubReleasesSource } from "blume/sources/github-releases.ts";
import redirects from "./redirects";

/**
 * GitHub releases → /changelog, dated by the topic's real finish instant.
 *
 * Blume dates a release entry by `published_at`, which the GitHub API cannot
 * backdate — so the topic releases backfilled on one day (apps/cli/
 * release-topics.ts) would all read that day. Their tags are timever
 * (`YYYYMMDD.HHMMSS.NNNNNNNNN`, UTC) of the moment the topic finished, so this
 * fetch rewrites each timever release's `published_at` to that instant before
 * Blume maps it; anything else passes through untouched. The config-level
 * `githubReleases()` accepts no `fetchImpl`, hence the `custom()` wrap of the
 * underlying source (the `blume/sources/*.ts` path the Blume docs use for
 * custom sources), with the context the built-in adapter would receive.
 */
const TIMEVER = /^(\d{4})(\d{2})(\d{2})\.(\d{2})(\d{2})(\d{2})\.\d{9}$/;

const releasesDatedByTag: typeof fetch = async (input, init) => {
  const res = await fetch(input, init);
  if (!res.ok) return res;
  const releases: unknown = await res.json();
  if (Array.isArray(releases)) {
    for (const release of releases) {
      const m = typeof release?.tag_name === "string" ? release.tag_name.match(TIMEVER) : null;
      if (m) release.published_at = `${m[1]}-${m[2]}-${m[3]}T${m[4]}:${m[5]}:${m[6]}Z`;
    }
  }
  // Blume reads only `ok` and the JSON body, so the original headers (whose
  // content-length/encoding describe the upstream bytes) are not carried over.
  return Response.json(releases, { status: res.status });
};

// Blume's defaults (`inter`, `ibm-plex-mono`) are fetched from fonts.gstatic.com
// on every build, which has timed out on the Pages runner and, fully offline,
// silently ships no fonts at all. The same two families from Fontsource, as
// local files, keep the build network-free. Blume resolves `src` from this
// directory; the workspace links these packages under ./node_modules.
const inter = {
  name: "Inter",
  variants: [
    {
      src: "./node_modules/@fontsource-variable/inter/files/inter-latin-wght-normal.woff2",
      weight: "100..900",
    },
  ],
};
const plexMono = {
  name: "IBM Plex Mono",
  variants: [
    {
      src: "./node_modules/@fontsource/ibm-plex-mono/files/ibm-plex-mono-latin-400-normal.woff2",
      weight: 400,
    },
    {
      src: "./node_modules/@fontsource/ibm-plex-mono/files/ibm-plex-mono-latin-500-normal.woff2",
      weight: 500,
    },
  ],
};

export default defineConfig({
  title: "prdlk",
  description: "Documentation for my LeetCode solutions",
  logo: "./public/logo.svg",
  deployment: {
    site: "https://lc.prd.lk",
  },
  github: {
    owner: "prdlk",
    repo: "leetcode",
  },
  lastModified: "git",
  redirects,
  content: {
    sources: [
      filesystem({ root: "content" }),
      custom(
        githubReleasesSource(
          {
            name: "changelog",
            prefix: "changelog",
            owner: "prdlk",
            repo: "leetcode",
            fetchImpl: releasesDatedByTag,
          },
          // What resolve.ts hands the built-in adapter: `.blume/cache/<name>/`,
          // and a refresh on every load (the source reads nothing else).
          {
            projectRoot: import.meta.dirname,
            cacheDir: `${import.meta.dirname}/.blume/cache/changelog`,
            mode: "build",
          },
        ),
      ),
    ],
  },
  theme: {
    fonts: { display: inter, body: inter, mono: plexMono },
  },
  navigation: {
    sidebar: {
      display: "flat", // "flat" | "group" | "page"
    },
    tabs: [{ label: "Changelog", path: "/changelog" }],
  },
});