"use client";

import { Children, useEffect, useState, type ReactNode } from "react";

type Props = {
  open: boolean;
  onClose: () => void;
  title?: string;
  children: ReactNode;
};

const PANEL_MS = 420;
const ITEM_BASE_MS = 90;

function CloseIcon({ className }: { className?: string }) {
  return (
    <svg
      className={className}
      viewBox="0 0 24 24"
      fill="none"
      stroke="currentColor"
      strokeWidth="2"
    >
      <path d="M6 6l12 12M18 6L6 18" strokeLinecap="round" />
    </svg>
  );
}

export function MobileSidebar({ open, onClose, title = "Menu", children }: Props) {
  const [mounted, setMounted] = useState(false);
  const [visible, setVisible] = useState(false);

  useEffect(() => {
    if (open) {
      setMounted(true);
      const frame = requestAnimationFrame(() => setVisible(true));
      return () => cancelAnimationFrame(frame);
    }

    setVisible(false);
    const timer = window.setTimeout(() => setMounted(false), PANEL_MS);
    return () => window.clearTimeout(timer);
  }, [open]);

  useEffect(() => {
    if (!mounted) return;

    const onKeyDown = (e: KeyboardEvent) => {
      if (e.key === "Escape") onClose();
    };

    document.body.style.overflow = "hidden";
    window.addEventListener("keydown", onKeyDown);

    return () => {
      document.body.style.overflow = "";
      window.removeEventListener("keydown", onKeyDown);
    };
  }, [mounted, onClose]);

  if (!mounted) return null;

  return (
    <div className="fixed inset-0 z-50 sm:hidden">
      <button
        type="button"
        aria-label="Close menu"
        className={`absolute inset-0 bg-black/60 backdrop-blur-sm transition-opacity duration-300 ease-out ${
          visible ? "opacity-100" : "opacity-0"
        }`}
        onClick={onClose}
      />

      <button
        type="button"
        onClick={onClose}
        aria-label="Close menu"
        style={{ animationDelay: visible ? "120ms" : "0ms" }}
        className={`fixed right-4 top-4 z-[60] flex h-10 w-10 items-center justify-center rounded-full border border-gray-700 bg-surface text-gray-300 shadow-lg transition-shadow hover:bg-surface-light hover:text-white ${
          visible ? "mobile-sidebar-close-btn-open" : "mobile-sidebar-close-btn-close"
        }`}
      >
        <CloseIcon className="h-5 w-5" />
      </button>

      <aside
        className={`absolute right-0 top-0 flex h-full w-72 max-w-[85vw] flex-col border-l border-gray-800 bg-surface shadow-2xl ${
          visible ? "mobile-sidebar-panel-open" : "mobile-sidebar-panel-close"
        }`}
      >
        <div
          className={`border-b border-gray-800 px-5 py-5 transition-all duration-300 ease-out ${
            visible ? "translate-y-0 opacity-100" : "-translate-y-2 opacity-0"
          }`}
          style={{ transitionDelay: visible ? "100ms" : "0ms" }}
        >
          <span className="text-sm font-semibold uppercase tracking-wider text-gray-400">
            {title}
          </span>
        </div>

        <nav className="flex flex-1 flex-col gap-1 overflow-y-auto p-4">
          {Children.map(children, (child, index) => (
            <div
              key={index}
              className={`transition-all duration-300 ease-out ${
                visible ? "translate-x-0 opacity-100" : "translate-x-8 opacity-0"
              }`}
              style={{
                transitionDelay: visible ? `${ITEM_BASE_MS + index * 50}ms` : "0ms",
              }}
            >
              {child}
            </div>
          ))}
        </nav>
      </aside>
    </div>
  );
}

export function MobileMenuButton({
  onClick,
  open = false,
}: {
  onClick: () => void;
  open?: boolean;
}) {
  return (
    <button
      type="button"
      onClick={onClick}
      aria-label={open ? "Close menu" : "Open menu"}
      aria-expanded={open}
      className="relative rounded p-2 text-gray-300 transition-all duration-300 hover:scale-105 hover:bg-white/10 hover:text-white active:scale-95 sm:hidden"
    >
      <span className="relative block h-6 w-6">
        <span
          className={`absolute left-0 top-[5px] block h-0.5 w-6 rounded-full bg-current transition-all duration-300 ease-out ${
            open ? "top-[11px] rotate-45" : ""
          }`}
        />
        <span
          className={`absolute left-0 top-[11px] block h-0.5 w-6 rounded-full bg-current transition-all duration-300 ease-out ${
            open ? "scale-x-0 opacity-0" : ""
          }`}
        />
        <span
          className={`absolute left-0 top-[17px] block h-0.5 w-6 rounded-full bg-current transition-all duration-300 ease-out ${
            open ? "top-[11px] -rotate-45" : ""
          }`}
        />
      </span>
    </button>
  );
}

export function sidebarLinkClass(active = false) {
  return `block rounded-lg px-4 py-3 text-base font-medium transition-all duration-200 hover:translate-x-0.5 ${
    active ? "bg-surface-light text-white" : "text-gray-300 hover:bg-surface-light hover:text-white"
  }`;
}

export function dashboardSidebarLinkClass(active = false, danger = false) {
  const classes = ["mobile-sidebar-link"];
  if (active) classes.push("mobile-sidebar-link-active");
  if (danger) classes.push("mobile-sidebar-link-danger");
  return classes.join(" ");
}