import { notFound } from "next/navigation";
import Image from "next/image";
import { Metadata } from "next";
import { MDXRemote } from "next-mdx-remote/rsc";
import { Container } from "@/components/layout/Container";
import { Button } from "@/components/ui/Button";
import { getAllResources, getResourceBySlug } from "@/lib/resources";
import { ResourcesGrid } from "../resources-client";

function MdxLink(props: React.AnchorHTMLAttributes<HTMLAnchorElement>) {
  const { href, children, ...rest } = props;
  const isExternal = href?.startsWith("http");
  return (
    <a
      href={href}
      {...(isExternal ? { target: "_blank", rel: "noopener noreferrer" } : {})}
      {...rest}
    >
      {children}
    </a>
  );
}

const mdxComponents = {
  a: MdxLink,
};

const NEWS_CATEGORIES = ["News & Updates", "Customer Stories"];
const ACTIVITY_CATEGORIES = ["Activities", "Simulator Activities"];

const CATEGORY_SLUGS: Record<string, {
  name: string;
  description: string;
  matchCategories?: string[];
  filterCategories?: string[];
}> = {
  "getting-started": {
    name: "Getting Started",
    description: "Everything you need to get up and running with the Micromelon platform.",
  },
  activities: {
    name: "Activities",
    description: "Hands-on activities for the Micromelon Rover and Robot Simulator.",
    matchCategories: ["Activities", "Simulator Activities"],
    filterCategories: ["Activities", "Simulator Activities"],
  },
  "sensor-guides": {
    name: "Sensor Guides",
    description: "Learn how each sensor on the Micromelon Rover works and how to code it.",
  },
  "3d-printing-guides": {
    name: "3D Printing Guides",
    description: "Guides for designing, printing, and troubleshooting rover attachments.",
  },
  "advanced-guides": {
    name: "Advanced Guides",
    description: "I2C, UART, OpenMV, and other advanced topics for experienced users.",
  },
  "build-guides": {
    name: "Build Guides",
    description: "Step-by-step instructions for building rover attachments.",
  },
  "design-blogs": {
    name: "Design Blogs",
    description: "Read about the design process behind rover attachments.",
  },
};

interface ResourcePageProps {
  params: Promise<{ slug: string }>;
}

export function generateStaticParams() {
  const resources = getAllResources();
  const resourceParams = resources.map((resource) => ({
    slug: resource.slug,
  }));
  const categoryParams = Object.keys(CATEGORY_SLUGS).map((slug) => ({
    slug,
  }));
  return [...resourceParams, ...categoryParams];
}

export async function generateMetadata({
  params,
}: ResourcePageProps): Promise<Metadata> {
  const { slug } = await params;

  const category = CATEGORY_SLUGS[slug];
  if (category) {
    return {
      title: `${category.name} - Resources`,
      description: category.description,
    };
  }

  const resource = getResourceBySlug(slug);
  if (!resource) return {};
  return {
    title: resource.title,
    description: resource.excerpt,
  };
}

export default async function ResourcePage({ params }: ResourcePageProps) {
  const { slug } = await params;

  /* Category page */
  const category = CATEGORY_SLUGS[slug];
  if (category) {
    const cats = category.matchCategories || [category.name];
    const resources = getAllResources()
      .filter((r) => r.categories.some((c) => cats.includes(c)))
      .map(({ content, ...meta }) => meta);

    return (
      <>
        <section className="bg-white pt-16 sm:pt-20">
          <Container>
            <Button href="/resources" variant="outline" size="sm" className="mb-8">
              &larr; All Resources
            </Button>
          </Container>
        </section>
        <ResourcesGrid
          resources={resources}
          title={category.name}
          subtitle={category.description}
          filterCategories={category.filterCategories}
        />
      </>
    );
  }

  /* Individual resource page */
  const resource = getResourceBySlug(slug);

  if (!resource) {
    notFound();
  }

  const isNews = resource.categories.some((cat) =>
    NEWS_CATEGORIES.includes(cat)
  );
  const isActivity = resource.categories.some((cat) =>
    ACTIVITY_CATEGORIES.includes(cat)
  );

  if (isActivity) {
    return (
      <>
        {/* Activity Hero */}
        <section className="bg-white py-16 sm:py-24">
          <Container>
            <Button
              href="/resources"
              variant="outline"
              size="sm"
              className="mb-8"
            >
              &larr; Back to Resources
            </Button>
            <div className="grid items-center gap-12 md:grid-cols-2">
              <div>
                <div className="mb-3 flex flex-wrap gap-1.5">
                  {resource.categories.map((cat) => (
                    <span
                      key={cat}
                      className="rounded-full bg-muted px-2.5 py-0.5 text-xs font-medium text-muted-foreground"
                    >
                      {cat}
                    </span>
                  ))}
                </div>
                <h1 className="text-4xl font-bold tracking-tight text-foreground sm:text-5xl">
                  {resource.title}
                </h1>
                {(resource.codingSkills.length > 0 || resource.roverConcepts.length > 0) && (
                  <div className="mt-6 flex flex-wrap gap-x-8 gap-y-4">
                    {resource.codingSkills.length > 0 && (
                      <div>
                        <p className="mb-2 text-xs font-semibold uppercase tracking-wider text-muted-foreground">
                          Coding Skills
                        </p>
                        <div className="flex flex-wrap gap-1.5">
                          {resource.codingSkills.map((skill) => (
                            <span
                              key={skill}
                              className="rounded-full border border-brand/30 bg-brand/5 px-2.5 py-0.5 text-xs font-medium text-foreground"
                            >
                              {skill}
                            </span>
                          ))}
                        </div>
                      </div>
                    )}
                    {resource.roverConcepts.length > 0 && (
                      <div>
                        <p className="mb-2 text-xs font-semibold uppercase tracking-wider text-muted-foreground">
                          Rover Concepts
                        </p>
                        <div className="flex flex-wrap gap-1.5">
                          {resource.roverConcepts.map((concept) => (
                            <span
                              key={concept}
                              className="rounded-full border border-foreground/20 bg-foreground/5 px-2.5 py-0.5 text-xs font-medium text-foreground"
                            >
                              {concept}
                            </span>
                          ))}
                        </div>
                      </div>
                    )}
                  </div>
                )}
              </div>
              {resource.featuredImage && (
                <div>
                  <Image
                    src={resource.featuredImage}
                    alt={resource.title}
                    width={700}
                    height={700}
                    className="w-full rounded-2xl"
                    priority
                  />
                </div>
              )}
            </div>
          </Container>
        </section>

        {/* Activity Content */}
        <section className="border-t border-border bg-muted py-16">
          <Container className="max-w-3xl">
            <article className="mdx-content">
              <MDXRemote source={resource.content} components={mdxComponents} />
            </article>
            <div className="mt-12 border-t border-border pt-8">
              <Button href="/resources" variant="outline" size="sm">
                &larr; Return to Resources
              </Button>
            </div>
          </Container>
        </section>
      </>
    );
  }

  const backHref = isNews ? "/news" : "/resources";
  const backLabel = isNews ? "Back to News" : "Back to Resources";
  const returnLabel = isNews ? "Return to News" : "Return to Resources";

  return (
    <>
      {/* Hero */}
      <section className="bg-white py-16 sm:py-24">
        <Container>
          <Button href={backHref} variant="outline" size="sm" className="mb-8">
            &larr; {backLabel}
          </Button>
          <div className="grid items-center gap-12 md:grid-cols-2">
            <div>
              <div className="mb-3 flex flex-wrap gap-1.5">
                {resource.categories.map((cat) => (
                  <span
                    key={cat}
                    className="rounded-full bg-muted px-2.5 py-0.5 text-xs font-medium text-muted-foreground"
                  >
                    {cat}
                  </span>
                ))}
              </div>
              <h1 className="text-4xl font-bold tracking-tight text-foreground sm:text-5xl">
                {resource.title}
              </h1>
              <p className="mt-3 text-muted-foreground">
                {new Date(resource.date).toLocaleDateString("en-AU", {
                  year: "numeric",
                  month: "long",
                  day: "numeric",
                })}
              </p>
            </div>
            {resource.featuredImage && (
              <div>
                <Image
                  src={resource.featuredImage}
                  alt={resource.title}
                  width={700}
                  height={467}
                  className="w-full rounded-2xl"
                  priority
                />
              </div>
            )}
          </div>
        </Container>
      </section>

      {/* Content */}
      <section className="border-t border-border bg-muted py-16">
        <Container className="max-w-3xl">
          <article className="mdx-content">
            <MDXRemote source={resource.content} components={mdxComponents} />
          </article>
          <div className="mt-12 border-t border-border pt-8">
            <Button href={backHref} variant="outline" size="sm">
              &larr; {returnLabel}
            </Button>
          </div>
        </Container>
      </section>
    </>
  );
}