import type { CSSProperties, ReactNode } from "react";
import Link from "next/link";
import GlobeCanvas from "@/components/globe-canvas";
import StatCounter from "@/components/stat-counter";
import RevealObserver from "@/components/reveal-observer";
import ContactForm from "./contact-form";
import type { Item, Page, Section } from "@/lib/pages";
import { SITE_URL, hrefFor } from "@/lib/routes";

type Vars = CSSProperties & Record<`--${string}`, string | number>;
const delay = (ms: number) => ({ "--d": `${ms}ms` }) as Vars;
const pad = (n: number) => String(n).padStart(2, "0");

export type Crumb = { name: string; href: string };

const Arrow = () => <span className="arrow">→</span>;

function Eyebrow({ index, children }: { index?: string; children: ReactNode }) {
  return (
    <p className="eyebrow">
      {index && <span className="idx">{index}</span>}
      {children}
    </p>
  );
}

/** "> " marks a sentence that was bold in the copy deck. */
function Para({ text, className }: { text: string; className?: string }) {
  if (text.startsWith("> ")) return <p className="emph">{text.slice(2)}</p>;
  return <p className={className}>{text}</p>;
}

function Paras({ items, firstClass }: { items: string[]; firstClass?: string }) {
  return (
    <>
      {items.map((t, i) => (
        <Para key={i} text={t} className={i === 0 ? firstClass : undefined} />
      ))}
    </>
  );
}

function CtaLinks({ ctas, path }: { ctas: string[]; path: string }) {
  if (!ctas.length) return null;
  return (
    <div className="cta-row">
      {ctas.map((c) => (
        <Link key={c} href={hrefFor(c, path)} className="arrow-link">
          {c} <Arrow />
        </Link>
      ))}
    </div>
  );
}

function SectionHead({ section, index }: { section: Section; index: number }) {
  const isFaq = section.kind === "faq";
  const eyebrow = isFaq && !section.title ? null : section.eyebrow;
  const title = section.title ?? (isFaq ? "Frequently Asked Questions" : null);
  return (
    <div className="section-head">
      <div className="title" data-reveal>
        {eyebrow && <Eyebrow index={pad(index)}>{eyebrow}</Eyebrow>}
        {title && <h2 className="display h2">{title}</h2>}
      </div>
    </div>
  );
}

function Intro({ section }: { section: Section }) {
  const { intro } = section;
  if (!intro.length) return null;
  if (intro.length === 1) {
    return (
      <div className="split" data-reveal>
        <div className="lead">
          <Para text={intro[0]} />
        </div>
        <div />
      </div>
    );
  }
  return (
    <div className="split">
      <div className="lead" data-reveal>
        <Para text={intro[0]} />
      </div>
      <div className="copy" data-reveal style={delay(140)}>
        <Paras items={intro.slice(1)} firstClass="hl" />
      </div>
    </div>
  );
}

function Outro({ section, path }: { section: Section; path: string }) {
  if (!section.outro.length && !section.ctas.length) return null;
  return (
    <div className="outro" data-reveal>
      {section.outro.length > 0 && (
        <div className="outro-copy">
          <Paras items={section.outro} />
        </div>
      )}
      <CtaLinks ctas={section.ctas} path={path} />
    </div>
  );
}

function ItemList({ list }: { list: string[] }) {
  if (!list.length) return null;
  return (
    <ul className="tick-list">
      {list.map((l) => (
        <li key={l}>{l}</li>
      ))}
    </ul>
  );
}

function columnsFor(items: Item[]) {
  const n = items.length;
  const avg = items.reduce((a, it) => a + it.body.join(" ").length, 0) / Math.max(n, 1);
  if (n === 2 || (n === 4 && avg > 240)) return 2;
  if (n === 4) return 4;
  return 3;
}

/* ───────────── Section variants ───────────── */

function TextSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      {section.ctas.length > 0 && (
        <div className="split">
          <div />
          <div data-reveal>
            <CtaLinks ctas={section.ctas} path={path} />
          </div>
        </div>
      )}
    </>
  );
}

function CardsSection({ section, path }: { section: Section; path: string }) {
  const cols = columnsFor(section.items);
  return (
    <>
      <Intro section={section} />
      <div className="card-grid" style={{ "--cols": cols } as Vars}>
        {section.items.map((it, i) => (
          <article key={it.title} className="card" data-reveal style={delay((i % cols) * 90)}>
            <span className="card-num">{pad(i + 1)}</span>
            <h3 className="card-title">{it.title}</h3>
            {it.subtitle && <p className="card-sub">{it.subtitle}</p>}
            {it.body.length > 0 && (
              <div className="copy">
                <Paras items={it.body} firstClass="hl" />
              </div>
            )}
            <ItemList list={it.list} />
            {it.cta && (
              <Link href={hrefFor(it.cta, path)} className="arrow-link">
                {it.cta} <Arrow />
              </Link>
            )}
          </article>
        ))}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function StepsSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      <ol className="steps">
        {section.items.map((it, i) => (
          <li key={it.title} className="step" data-reveal style={delay(i * 70)}>
            <span className="step-num">{it.num ?? pad(i + 1)}</span>
            <h3 className="step-title">{it.title}</h3>
            <div className="copy">
              <Paras items={it.body} firstClass="hl" />
            </div>
          </li>
        ))}
      </ol>
      <Outro section={section} path={path} />
    </>
  );
}

function FaqSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      <div className="faq">
        {section.items.map((it, i) => (
          <details key={it.title} className="faq-item" data-reveal style={delay(i * 50)} open={i === 0}>
            <summary>
              <span>{it.title}</span>
              <i aria-hidden="true" />
            </summary>
            <div className="copy">
              <Paras items={it.body} />
            </div>
          </details>
        ))}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function LinksSection({ section, path }: { section: Section; path: string }) {
  const cols = columnsFor(section.items);
  return (
    <>
      <Intro section={section} />
      <div className="card-grid link-grid" style={{ "--cols": cols } as Vars}>
        {section.items.map((it, i) => (
          <Link
            key={it.title}
            href={hrefFor(it.cta ?? "", path)}
            className="card link-card"
            data-reveal
            style={delay((i % cols) * 90)}
          >
            <span className="card-num">{pad(i + 1)}</span>
            <h3 className="card-title">{it.title}</h3>
            <div className="copy">
              <Paras items={it.body} firstClass="hl" />
            </div>
            <span className="arrow-link">
              {it.cta} <Arrow />
            </span>
          </Link>
        ))}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function StatsSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      <div className="stats">
        {section.items.map((it, i) => {
          const m = it.title.match(/^([\d.,]+)(.*)$/);
          const value = m ? Number(m[1].replace(/,/g, "")) : 0;
          return (
            <div key={it.title} className="stat" data-reveal style={delay(i * 120)}>
              <StatCounter value={value} suffix={m ? m[2] : ""} />
              <div className="stat-label">{it.subtitle}</div>
              <div className="copy stat-copy">
                <Paras items={it.body} />
              </div>
            </div>
          );
        })}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function AddressLines({ text }: { text: string }) {
  return (
    <address className="office-address">
      {text.split("\n").map((line) => {
        const [label, ...rest] = line.split(":");
        const value = rest.join(":").trim();
        if (/^phone$/i.test(label.trim()) && value) {
          return (
            <span key={line}>
              <em>Phone</em>
              <a href={`tel:${value.replace(/[^\d+]/g, "")}`}>{value}</a>
            </span>
          );
        }
        if (/^email$/i.test(label.trim()) && value) {
          return (
            <span key={line}>
              <em>Email</em>
              <a href={`mailto:${value}`}>{value}</a>
            </span>
          );
        }
        return <span key={line}>{line}</span>;
      })}
    </address>
  );
}

function OfficesSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      <div className="offices">
        {section.items.map((it, i) => {
          const address = it.body.find((b) => b.includes("Phone:"));
          const desc = it.body.filter((b) => b !== address);
          return (
            <article key={it.title} className="office" data-reveal style={delay(i * 100)}>
              <div className="office-head">
                <h3 className="card-title">{it.title}</h3>
                {it.subtitle && <span className="pill">{it.subtitle}</span>}
              </div>
              <div className="copy">
                <Paras items={desc} />
              </div>
              {address && <AddressLines text={address} />}
            </article>
          );
        })}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function ShowcaseSection({ section, path }: { section: Section; path: string }) {
  return (
    <>
      <Intro section={section} />
      <div className="showcase">
        {section.items.map((it, i) => {
          const [name, tagline] = (it.kicker ?? "").split("|").map((s) => s.trim());
          return (
            <article key={it.title} className="showcase-row" data-reveal>
              <div className="showcase-name">
                <span className="card-num">{pad(i + 1)}</span>
                <h3>{name}</h3>
                {tagline && <p className="card-sub">{tagline}</p>}
              </div>
              <div className="showcase-body">
                <h4 className="display h3">{it.title}</h4>
                <div className="copy">
                  <Paras items={it.body} firstClass="hl" />
                </div>
                {it.cta && (
                  <Link href={hrefFor(it.cta, path)} className="arrow-link">
                    {it.cta} <Arrow />
                  </Link>
                )}
              </div>
              <ItemList list={it.list} />
            </article>
          );
        })}
      </div>
      <Outro section={section} path={path} />
    </>
  );
}

function FormSection({ section, path }: { section: Section; path: string }) {
  return (
    <div className="form-layout">
      <div className="form-copy">
        <div className="lead" data-reveal>
          <Para text={section.intro[0] ?? ""} />
        </div>
        <div className="copy" data-reveal style={delay(120)}>
          <Paras items={section.intro.slice(1)} />
        </div>
        <CtaLinks ctas={section.ctas} path={path} />
      </div>
      <div data-reveal style={delay(200)}>
        <ContactForm />
      </div>
    </div>
  );
}

const variants: Record<string, (p: { section: Section; path: string }) => ReactNode> = {
  text: TextSection,
  cards: CardsSection,
  steps: StepsSection,
  faq: FaqSection,
  links: LinksSection,
  stats: StatsSection,
  offices: OfficesSection,
  showcase: ShowcaseSection,
};

/* ───────────── Hero & closing CTA ───────────── */

function PageHero({ page, crumbs }: { page: Page; crumbs: Crumb[] }) {
  const { hero, path } = page;
  const [name, tagline] = (hero.eyebrow ?? "").split("|").map((s) => s.trim());
  return (
    <section className="hero page-hero" aria-labelledby="page-title">
      <GlobeCanvas />
      <div className="wrap hero-inner">
        <nav className="crumbs" aria-label="Breadcrumb" data-reveal>
          {crumbs.map((c, i) =>
            i < crumbs.length - 1 ? (
              <span key={c.href}>
                <Link href={c.href}>{c.name}</Link>
                <i aria-hidden="true">/</i>
              </span>
            ) : (
              <span key={c.href} aria-current="page">
                {c.name}
              </span>
            ),
          )}
        </nav>
        <div data-reveal style={delay(60)}>
          <Eyebrow>
            {tagline ? (
              <>
                <span className="idx">{name}</span> {tagline}
              </>
            ) : (
              name
            )}
          </Eyebrow>
        </div>
        <h1 id="page-title" className="display h1" data-reveal style={delay(120)}>
          {hero.title}
        </h1>
        <div className="hero-grid">
          <div className="hero-lead lead" data-reveal style={delay(240)}>
            <Para text={hero.intro[0] ?? ""} />
          </div>
          <div className="hero-body" data-reveal style={delay(340)}>
            {hero.intro.length > 1 && (
              <div className="copy">
                <Paras items={hero.intro.slice(1)} />
              </div>
            )}
            <div className="hero-actions">
              {hero.ctas.map((c, i) => (
                <Link key={c} href={hrefFor(c, path)} className={`btn ${i === 0 ? "btn-solid" : "btn-ghost"}`}>
                  {c} <Arrow />
                </Link>
              ))}
            </div>
          </div>
        </div>
      </div>
    </section>
  );
}

function ClosingCta({ section, path }: { section: Section; path: string }) {
  const [lead, ...rest] = section.intro;
  return (
    <section className="cta" aria-label={section.title ?? undefined}>
      <GlobeCanvas layout="center" />
      <div className="wrap">
        {section.eyebrow && (
          <div data-reveal>
            <Eyebrow>{section.eyebrow}</Eyebrow>
          </div>
        )}
        <h2 className="display h2" data-reveal style={delay(120)}>
          {section.title}
        </h2>
        {lead && (
          <div className="copy" data-reveal style={delay(240)}>
            <Paras items={[lead, ...rest]} />
          </div>
        )}
        {section.ctas.length > 0 && (
          <div data-reveal style={delay(360)}>
            {section.ctas.map((c) => (
              <Link key={c} href={hrefFor(c, path)} className="btn btn-solid">
                {c} <Arrow />
              </Link>
            ))}
          </div>
        )}
      </div>
    </section>
  );
}

/* ───────────── Structured data ───────────── */

function JsonLd({ page, crumbs }: { page: Page; crumbs: Crumb[] }) {
  const faqs = page.sections.filter((s) => s.kind === "faq").flatMap((s) => s.items);
  const graph: object[] = [
    {
      "@type": "BreadcrumbList",
      itemListElement: crumbs.map((c, i) => ({
        "@type": "ListItem",
        position: i + 1,
        name: c.name,
        item: SITE_URL + (c.href === "/" ? "" : c.href),
      })),
    },
  ];
  if (faqs.length) {
    graph.push({
      "@type": "FAQPage",
      mainEntity: faqs.map((f) => ({
        "@type": "Question",
        name: f.title,
        acceptedAnswer: { "@type": "Answer", text: f.body.join(" ") },
      })),
    });
  }
  const json = JSON.stringify({ "@context": "https://schema.org", "@graph": graph }).replace(/</g, "\\u003c");
  return <script type="application/ld+json" dangerouslySetInnerHTML={{ __html: json }} />;
}

/* ───────────── Page ───────────── */

export default function ContentPage({ page, crumbs }: { page: Page; crumbs: Crumb[] }) {
  const last = page.sections[page.sections.length - 1];
  const closing = last && last.kind === "text" && last.ctas.length > 0 ? last : null;
  const body = closing ? page.sections.slice(0, -1) : page.sections;

  return (
    <>
      <JsonLd page={page} crumbs={crumbs} />
      <PageHero page={page} crumbs={crumbs} />
      {body.map((section, i) => {
        const Variant = variants[section.kind] ?? TextSection;
        return (
          <section
            key={i}
            id={section.form ? "contact-form" : undefined}
            className={`section${i % 2 === 0 ? " section-night" : ""} kind-${section.kind}`}
          >
            <div className="wrap">
              <SectionHead section={section} index={i + 1} />
              {section.form ? (
                <FormSection section={section} path={page.path} />
              ) : (
                <Variant section={section} path={page.path} />
              )}
            </div>
          </section>
        );
      })}
      {closing && <ClosingCta section={closing} path={page.path} />}
      <RevealObserver />
    </>
  );
}