import Link from "next/link";
import type { CSSProperties, ReactNode } from "react";
import { THEMES, type ThemeId } from "@/themes/registry";
import { getSettings } from "@/lib/settings";
import { isAdmin } from "@/lib/auth";
import ThemeSwitcher from "./ThemeSwitcher";
import Clock from "./Clock";

// Shared, theme-agnostic page chrome. Every theme restyles these `rb-` classes
// to look like its own OS/console. The HTML skeleton never changes.
export default async function Shell({
  theme,
  title,
  children,
}: {
  theme: ThemeId;
  title: string;
  children: ReactNode;
}) {
  const settings = getSettings();
  const admin = await isAdmin();

  // Admins always get the switcher with every skin; the public only sees it when
  // enabled, and only the allowed skins.
  const showSwitcher = admin || settings.publicThemeToggle;
  const switcherThemes = admin
    ? THEMES
    : THEMES.filter((t) => settings.allowedThemes.includes(t.id));

  return (
    <div className="rb-desktop">
      {/* Decorative background field. Hidden by default; themes opt in
          (PS2 uses it for the BIOS bobbing-cube field). */}
      <div className="rb-bg" aria-hidden>
        <div className="rb-bg-grid">
          {Array.from({ length: 15 * 13 }).map((_, i) => {
            // deterministic pseudo-random thickness + bob phase per cube
            const h = 34 + ((i * 53) % 78);
            const delay = (((i * 37) % 100) / 100) * 4;
            return (
              <span
                key={i}
                className="rb-cube"
                style={
                  {
                    "--cube-h": `${h}px`,
                    "--cube-delay": `${delay.toFixed(2)}s`,
                  } as CSSProperties
                }
              />
            );
          })}
        </div>
      </div>

      <div className="rb-window" role="application">
        <div className="rb-titlebar">
          <span className="rb-titlebar-icon" aria-hidden />
          <span className="rb-titlebar-text">
            {title} — {settings.title}
          </span>
          <div className="rb-titlebar-buttons" aria-hidden>
            <button className="rb-tb-btn rb-tb-min" tabIndex={-1}>
              <span>_</span>
            </button>
            <button className="rb-tb-btn rb-tb-max" tabIndex={-1}>
              <span>□</span>
            </button>
            <button className="rb-tb-btn rb-tb-close" tabIndex={-1}>
              <span>×</span>
            </button>
          </div>
        </div>

        <nav className="rb-menubar" aria-label="Main">
          <Link className="rb-menu-link" href="/">
            Home
          </Link>
          <Link className="rb-menu-link" href="/about">
            About
          </Link>
          {admin && (
            <Link className="rb-menu-link" href="/admin">
              Admin
            </Link>
          )}
          <span className="rb-spacer" />
          {showSwitcher && (
            <ThemeSwitcher initial={theme} themes={switcherThemes} />
          )}
        </nav>

        <div className="rb-content">{children}</div>

        <div className="rb-statusbar">
          <span className="rb-status-cell">Ready</span>
          <span className="rb-status-cell rb-status-grow">
            {settings.footer}
          </span>
        </div>
      </div>

      <div className="rb-taskbar">
        <button className="rb-start">
          <span className="rb-start-logo" aria-hidden />
          start
        </button>
        <div className="rb-tasks">
          <button className="rb-task rb-task-active">
            <span className="rb-task-icon" aria-hidden />
            {settings.title}
          </button>
        </div>
        <div className="rb-tray">
          <Clock />
        </div>
      </div>
    </div>
  );
}