import React, { useEffect, useState } from "react";
import clsx from "clsx";

const rotationDuration = 3800;

const COIN_ANIM: Record<string, string> = {
  "front-front": "animate-coin-front-front",
  "front-back": "animate-coin-front-back",
  "back-front": "animate-coin-back-front",
  "back-back": "animate-coin-back-back",
};

function Coin(props: {
  frontList: boolean[];
  rotation: boolean;
  onTransitionEnd: () => void;
}) {
  const [lastFront, setLastFront] = useState(props.frontList);

  useEffect(() => {
    if (!props.rotation) {
      return;
    }
    const id = setTimeout(() => {
      setLastFront(props.frontList);
      props.onTransitionEnd();
    }, rotationDuration);
    return () => clearTimeout(id);
  }, [props.rotation, props.frontList, props.onTransitionEnd]);

  return (
    <div className="flex w-full max-w-md justify-around rounded-md border bg-secondary p-4 shadow dark:border-0 dark:shadow-none sm:p-6">
      {props.frontList.map((value, index) => (
        <CoinItem
          key={index}
          front={value}
          lastFront={lastFront[index]}
          rotation={props.rotation}
        />
      ))}
    </div>
  );
}

/** 方孔铜钱造型 */
function CoinFace({ side }: { side: "front" | "back" }) {
  const isFront = side === "front";
  return (
    <div
      className={clsx(
        "absolute inset-0 rounded-full border-[3px] shadow-md",
        isFront
          ? "border-amber-600 bg-gradient-to-br from-amber-300 via-amber-400 to-amber-600"
          : "border-stone-600 bg-gradient-to-br from-stone-400 via-stone-500 to-stone-700",
      )}
      style={{
        backfaceVisibility: "hidden",
        transform: isFront ? undefined : "rotateY(180deg)",
      }}
    >
      <div className="absolute inset-[18%] rounded-sm border-2 border-amber-800/40 bg-amber-900/10" />
      <span
        className={clsx(
          "absolute bottom-1 left-0 right-0 text-center text-[10px] font-bold sm:text-xs",
          isFront ? "text-amber-950/80" : "text-stone-200/90",
        )}
      >
        {isFront ? "乾" : "坤"}
      </span>
    </div>
  );
}

function CoinItem(props: {
  front: boolean;
  lastFront: boolean;
  rotation: boolean;
}) {
  const animKey = `${getFront(props.lastFront)}-${getFront(props.front)}`;
  const animClass = props.rotation ? COIN_ANIM[animKey] : "";

  return (
    <div className="h-[4.5rem] w-[4.5rem] sm:h-20 sm:w-20" style={{ perspective: "900px" }}>
      <div
        style={{
          transform: `rotateY(${props.front ? 0 : 180}deg)`,
          transformStyle: "preserve-3d",
        }}
        className={clsx("relative h-full w-full", animClass)}
      >
        <CoinFace side="front" />
        <CoinFace side="back" />
      </div>
    </div>
  );
}

function getFront(front: boolean): string {
  return front ? "front" : "back";
}

export default Coin;