"use client";

import { useRef, useState, type KeyboardEvent } from "react";
import { AnimatePresence, motion, useAnimationControls, useReducedMotion } from "motion/react";

type TagForgeProps = {
  /** Read out by screen readers and shown over the bar. */
  label?: string;
  /** Form field name. Each tag is sent as its own field. */
  name?: string;
  /** Tags on the rack at start. */
  defaultValue?: string[];
  /** Most tags the rack takes. */
  max?: number;
  placeholder?: string;
  /** Called with all tags on every change. */
  onChange?: (tags: string[]) => void;
  /** Set the width here. Everything scales with it. */
  className?: string;
};

type Spark = { x: number; y: number; size: number; time: number };

const TAG_SHAPE = "polygon(14% 0, 86% 0, 100% 24%, 100% 100%, 0 100%, 0 24%)";

const makeSparks = () =>
  Array.from({ length: 14 }, () => {
    const a = -Math.PI * (0.08 + Math.random() * 0.84);
    const r = 8 + Math.random() * 24;
    return { x: Math.cos(a) * r, y: Math.sin(a) * r, size: 0.4 + Math.random() * 0.5, time: 0.35 + Math.random() * 0.35 };
  });

/* TagForge: type a word and strike it. The hammer lands, sparks fly, and the word comes off the anvil as a glowing steel tag that cools on its hook and swings to a stop. A normal tag input underneath: Enter or comma forges, Backspace takes the last one down. */
export function TagForge({ label = "Tags", name, defaultValue = [], max = 6, placeholder = "Type a word", onChange, className = "w-full max-w-lg" }: TagForgeProps) {
  const reduce = useReducedMotion();
  const hammer = useAnimationControls();
  const bar = useAnimationControls();
  const input = useRef<HTMLInputElement>(null);
  const [tags, setTags] = useState(defaultValue);
  const [word, setWord] = useState("");
  const [note, setNote] = useState("");
  const [sparks, setSparks] = useState<{ id: number; list: Spark[] }>({ id: 0, list: [] });

  const update = (next: string[], message: string) => {
    setTags(next);
    setNote(message);
    onChange?.(next);
  };

  const refuse = (message: string) => {
    setNote(message);
    if (!reduce) bar.start({ x: [0, -7, 7, -4, 4, 0], transition: { duration: 0.3 } });
  };

  const forge = () => {
    const text = word.trim();
    if (!text) return input.current?.focus();
    if (tags.some((t) => t.toLowerCase() === text.toLowerCase())) return refuse(`${text} is already on the rack`);
    if (tags.length >= max) return refuse(`The rack is full, ${max} tags`);
    if (!reduce) {
      hammer.start({ rotate: [-34, 12, 8, -34], transition: { duration: 0.6, times: [0, 0.2, 0.3, 1], ease: ["easeIn", "linear", "easeInOut"] } });
      setSparks({ id: sparks.id + 1, list: makeSparks() });
    }
    update([...tags, text], `${text} added`);
    setWord("");
    input.current?.focus();
  };

  const remove = (tag: string) => {
    update(
      tags.filter((t) => t !== tag),
      `${tag} removed`,
    );
    input.current?.focus();
  };

  const keys = (e: KeyboardEvent<HTMLInputElement>) => {
    if (e.key === "Enter" || e.key === ",") {
      e.preventDefault();
      forge();
    } else if (e.key === "Backspace" && !word && tags.length) {
      remove(tags[tags.length - 1]);
    }
  };

  return (
    <div
      className={`relative @container overflow-hidden rounded-[2cqw] bg-[radial-gradient(120%_70%_at_50%_112%,#a13c0d_0%,#3a1a0c_42%,#14100e_78%)] px-[4cqw] pt-[3cqw] ${className}`}
      style={{ aspectRatio: "520 / 320" }}
    >
      <ul
        aria-label={label}
        className="flex min-h-[28cqw] flex-wrap content-start gap-x-[2cqw] bg-[linear-gradient(#4a4039_0_0.7cqw,transparent_0.7cqw)] bg-[length:100%_14cqw]"
      >
        <AnimatePresence initial={false}>
          {tags.map((tag) => (
            <motion.li
              key={tag}
              layout={reduce ? false : "position"}
              initial={reduce ? false : { y: 26, opacity: 0, rotate: -18 }}
              animate={reduce ? { rotate: 0 } : { y: 0, opacity: 1, rotate: [-18, 12, -7, 4, -2, 0] }}
              exit={reduce ? { opacity: 0, transition: { duration: 0 } } : { y: 34, opacity: 0, rotate: 24, transition: { duration: 0.3, ease: "easeIn" } }}
              transition={{ y: { duration: 0.22 }, opacity: { duration: 0.12 }, rotate: { duration: 1.5, ease: "easeOut" } }}
              whileHover={reduce ? undefined : { rotate: 3 }}
              className="relative h-[14cqw] origin-[50%_0.4cqw] pt-[3.2cqw] drop-shadow-[0_0.8cqw_0.6cqw_rgba(0,0,0,0.55)]"
            >
              <span aria-hidden className="absolute top-0 left-1/2 h-[4.6cqw] w-[2.2cqw] -translate-x-1/2 rounded-b-full border-[0.5cqw] border-t-0 border-[#9a9185]" />
              <div className="relative flex h-[9.6cqw] items-center gap-[0.8cqw] bg-[linear-gradient(160deg,#d7dade_0%,#9ba1a8_46%,#c5c9ce_100%)] pr-[0.8cqw] pl-[2.2cqw] pt-[1.5cqw]" style={{ clipPath: TAG_SHAPE }}>
                <motion.span
                  aria-hidden
                  initial={reduce ? false : { opacity: 1 }}
                  animate={{ opacity: 0 }}
                  transition={{ duration: 1.8, ease: "easeIn" }}
                  className="absolute inset-0 bg-[linear-gradient(160deg,#ffe08a,#ff7a1a_55%,#d9360f)]"
                />
                <span aria-hidden className="absolute top-[0.9cqw] left-1/2 size-[1.4cqw] -translate-x-1/2 rounded-full bg-[#2a221d]" />
                <span className="relative font-mono text-[3.2cqw] font-bold tracking-[0.08em] text-[#23262a] uppercase [text-shadow:0_0.15cqw_0_rgba(255,255,255,0.55)]">{tag}</span>
                <button
                  type="button"
                  onClick={() => remove(tag)}
                  aria-label={`Remove ${tag}`}
                  className="relative grid h-[7.4cqw] w-[6cqw] shrink-0 place-items-center rounded-full font-mono text-[3.2cqw] leading-none text-[#3c4046] transition-colors hover:bg-black/15 focus-visible:outline-2 focus-visible:-outline-offset-2 focus-visible:outline-[#b5330c]"
                >
                  ×
                </button>
              </div>
            </motion.li>
          ))}
        </AnimatePresence>
      </ul>

      <div className="relative mx-auto mt-[1cqw] w-[82%]">
        <div aria-hidden className="pointer-events-none absolute top-[0] left-[72%] z-10">
          <AnimatePresence>
            {sparks.list.map(
              (s, i) => (
                <motion.span
                  key={`${sparks.id}-${i}`}
                  initial={{ x: 0, y: 0, opacity: 1 }}
                  animate={{ x: `${s.x}cqw`, y: [`0cqw`, `${s.y}cqw`, `${s.y + 7}cqw`], opacity: 0 }}
                  transition={{ duration: s.time, delay: 0.12, ease: "easeOut" }}
                  className="absolute rounded-full bg-[#ffd27a] shadow-[0_0_1cqw_#ff8a2a]"
                  style={{ width: `${s.size}cqw`, height: `${s.size}cqw` }}
                />
              ),
            )}
          </AnimatePresence>
        </div>

        <motion.div animate={bar} className="relative z-[1]">
          <input
            ref={input}
            value={word}
            onChange={(e) => setWord(e.target.value)}
            onKeyDown={keys}
            aria-label={`${label}, press Enter to add`}
            placeholder={placeholder}
            maxLength={14}
            autoComplete="off"
            style={{ outline: "none" }}
            className="w-full rounded-[0.8cqw] border-[0.25cqw] border-[#5b5049] bg-[linear-gradient(#332c28,#1f1a17)] py-[1.5cqw] pr-[20cqw] pl-[2.6cqw] font-mono text-[4.2cqw] text-[#ffd9a0] uppercase caret-[#ff8a2a] shadow-[inset_0_-0.4cqw_0_#120e0c] transition-[border-color,box-shadow] placeholder:text-[#a18d7c] placeholder:normal-case focus:border-[#ff8a2a] focus:shadow-[inset_0_-0.4cqw_0_#120e0c,0_0_3cqw_-0.4cqw_#ff7a1a] focus:outline-none"
          />
        </motion.div>

        {/* The anvil under the bar. */}
        <svg aria-hidden viewBox="0 0 430 60" className="relative mx-auto -mt-[0.4cqw] w-full">
          <path d="M4 0H392C412 2 424 9 428 16C400 18 340 18 322 24C310 30 306 40 318 50H334V60H104V50H122C134 40 126 28 106 24C70 17 30 12 4 0Z" fill="#26211e" />
          <path d="M4 0H392C412 2 424 9 428 16" fill="none" stroke="#6a5e55" strokeWidth="1.4" />
        </svg>

        <motion.button
          type="button"
          onClick={forge}
          aria-label="Forge tag"
          initial={{ rotate: -34 }}
          animate={hammer}
          style={{ transformOrigin: "88% 82%" }}
          className="absolute right-[1%] -top-[11cqw] z-20 w-[24cqw] rounded-[1cqw] focus-visible:outline-2 focus-visible:outline-offset-1 focus-visible:outline-[#ffb36b]"
        >
          <svg aria-hidden viewBox="0 0 120 84" className="w-full drop-shadow-[0_0.6cqw_0.6cqw_rgba(0,0,0,0.5)]">
            <rect x="26" y="34" width="92" height="9" rx="4" fill="#8a5a33" />
            <rect x="26" y="34" width="92" height="3" rx="1.5" fill="#a97345" />
            <path d="M4 18H34a4 4 0 0 1 4 4V56a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V22a4 4 0 0 1 4-4Z" fill="#5a616a" />
            <path d="M4 18H34a4 4 0 0 1 4 4v6H0v-6a4 4 0 0 1 4-4Z" fill="#7d858f" />
          </svg>
        </motion.button>
      </div>

      {name && tags.map((tag) => <input key={tag} type="hidden" name={name} value={tag} />)}
      <p aria-live="polite" className="sr-only">
        {note}
      </p>
    </div>
  );
}