"use client";

import { useId, type CSSProperties, type InputHTMLAttributes, type PointerEvent, type ReactNode } from "react";

type GlowInputProps = Omit<InputHTMLAttributes<HTMLInputElement>, "className"> & {
  /** Field name. Shown above the box. */
  label: string;
  /** Keep the label for screen readers only. */
  hideLabel?: boolean;
  /** Icon at the start of the box (an svg works best). */
  icon?: ReactNode;
  /** Small help text under the field. */
  hint?: string;
  /** Two glow colours: [start, end]. */
  colors?: [string, string];
  /** Wrapper look (width etc.). */
  className?: string;
};

/* GlowInput: the border lights up under the pointer as you hover, and the whole edge glows in a gradient once the field has focus. */
export function GlowInput({
  label,
  hideLabel = false,
  icon,
  hint,
  colors = ["#a78bfa", "#22d3ee"],
  className = "w-full max-w-sm",
  id,
  ...rest
}: GlowInputProps) {
  const autoId = useId();
  const inputId = id ?? autoId;
  const hintId = `${inputId}-hint`;

  const track = (e: PointerEvent<HTMLDivElement>) => {
    const r = e.currentTarget.getBoundingClientRect();
    e.currentTarget.style.setProperty("--gx", `${e.clientX - r.left}px`);
    e.currentTarget.style.setProperty("--gy", `${e.clientY - r.top}px`);
  };

  const fade = "transition-opacity duration-300 motion-reduce:transition-none";
  const gradient = "linear-gradient(90deg, var(--g1), var(--g2))";

  return (
    <div className={className}>
      <label htmlFor={inputId} className={hideLabel ? "sr-only" : "mb-2 block text-sm font-medium text-white/80"}>
        {label}
      </label>
      <div
        onPointerMove={track}
        className="group relative rounded-xl p-px"
        style={{ "--g1": colors[0], "--g2": colors[1] } as CSSProperties}
      >
        <div aria-hidden className={`pointer-events-none absolute -inset-1 rounded-2xl opacity-0 blur-lg group-focus-within:opacity-40 ${fade}`} style={{ background: gradient }} />
        <div aria-hidden className="absolute inset-0 rounded-xl bg-white/12" />
        <div
          aria-hidden
          className={`absolute inset-0 rounded-xl opacity-0 group-hover:opacity-100 group-focus-within:opacity-0 ${fade}`}
          style={{ background: "radial-gradient(140px circle at var(--gx, 50%) var(--gy, 50%), var(--g1), transparent 70%)" }}
        />
        <div aria-hidden className={`absolute inset-0 rounded-xl opacity-0 group-focus-within:opacity-100 ${fade}`} style={{ background: gradient }} />
        <div className="relative flex items-center gap-2.5 rounded-[11px] bg-[#0f0d1c] px-3.5">
          {icon && (
            <span aria-hidden className="grid size-[18px] shrink-0 place-items-center text-white/40 transition-colors duration-300 group-focus-within:text-[var(--g1)] [&>svg]:size-full">
              {icon}
            </span>
          )}
          <input
            id={inputId}
            aria-describedby={hint ? hintId : undefined}
            className="h-12 w-full min-w-0 bg-transparent text-base text-white outline-none placeholder:text-white/30"
            {...rest}
          />
        </div>
      </div>
      {hint && (
        <p id={hintId} className="mt-1.5 px-1 text-xs text-white/45">
          {hint}
        </p>
      )}
    </div>
  );
}