import { defineConfig } from "blume";
import type { StandardSchema } from "blume/core/standard-schema.ts";
import { filesystem } from "blume/sources";
import { APPENDIX } from "./appendix";
import redirects from "./redirects";

// 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,
    },
  ],
};

/**
 * Custom frontmatter, rendered as the badge row by
 * components/ProblemBadges.astro. Problem pages: `topics:` is LeetCode's topic
 * tags and `issue:` the problem's GitHub issue URL (both written by
 * apps/cli/sync.ts), `video:` the NeetCode walkthrough's
 * YouTube id (apps/cli/videos.ts). Blume rejects undeclared keys and takes
 * any Standard Schema; these are hand-rolled so the docs workspace needs no
 * zod. All optional — every other page carries none.
 */
const optional = <T>(
  message: string,
  valid: (value: unknown) => value is T,
): StandardSchema<unknown, T | undefined> => ({
  "~standard": {
    version: 1,
    vendor: "prdlk",
    validate: (value) =>
      value === undefined || valid(value)
        ? { value }
        : { issues: [{ message }] },
  },
});

const topicsSchema = optional(
  "expected a list of { name, slug } LeetCode topic tags",
  (value): value is { name: string; slug: string }[] =>
    Array.isArray(value) &&
    value.every(
      (t) => typeof t?.name === "string" && typeof t?.slug === "string",
    ),
);
const videoSchema = optional(
  "expected an 11-character YouTube video id",
  (value): value is string =>
    typeof value === "string" && /^[\w-]{11}$/.test(value),
);
const issueSchema = optional(
  "expected a https://github.com/<owner>/<repo>/issues/<n> URL",
  (value): value is string =>
    typeof value === "string" &&
    /^https:\/\/github\.com\/[\w.-]+\/[\w.-]+\/issues\/\d+$/.test(value),
);

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",
  // Sync's `/<num>` short links, then the Appendix's former per-term pages
  // (`/appendix/<slug>`, published until the glossary became one page) onto
  // their cards, so old links and search results still land.
  redirects: [
    ...redirects,
    ...Object.keys(APPENDIX).map((slug) => ({
      from: `/appendix/${slug}`,
      to: `/appendix#${slug}`,
    })),
  ],
  frontmatter: {
    extend: {
      topics: topicsSchema,
      video: videoSchema,
      issue: issueSchema,
    },
  },
  seo: {
    og: { enabled: true },
    // No `rss`: the changelog is one custom page (pages/changelog.astro), not
    // `type: changelog` entries, so a changelog feed would have nothing in it.
    sitemap: true,
    robots: true,
    structuredData: true,
    x: { handle: "@prdlk" },
  },
  // Blume's own assistant route is server-rendered (it reads the provider key
  // per request), which a static Pages build cannot ship. The SRS Worker
  // answers instead (apps/api/src/ask.ts: OpenRouter, grounded on this site's
  // llms-full.txt, which `agents.llmsTxt` publishes).
  ai: {
    assistant: {
      enabled: true,
      endpoint: "https://srs-api.prdlk.workers.dev/ask",
    },
  },
  agents: {
    llmsTxt: true,
    mcp: { enabled: false },
  },
  // The only content source. `/changelog` and `/appendix` are custom pages
  // (pages/*.astro): `/changelog` reads the GitHub releases itself — one
  // timeline, no per-release pages — and `/appendix` is one glossary page
  // built from appendix.ts, so neither enters the sidebar tree or prev/next.
  content: {
    sources: [filesystem({ root: "content" })],
  },
  theme: {
    fonts: { display: inter, body: inter, mono: plexMono },
  },
  navigation: {
    repo: "https://github.com/prdlk/leetcode",
    sidebar: {
      display: "flat", // "flat" | "group" | "page"
    },
    // The two custom pages (pages/*.astro) as header tabs. Neither is a
    // content folder, so the tabs scope nothing out of the sidebar tree.
    tabs: [
      { label: "Changelog", path: "/changelog" },
      { label: "Appendix", path: "/appendix" },
    ],
  },
});