"use client";

import { useState, type ReactNode } from "react";
import { AnimatePresence, motion, useReducedMotion } from "motion/react";

type MorphActionProps = {
  children: ReactNode;
  className?: string;
  /** Runs on click. Return a promise and the button waits for it. */
  onClick?: () => unknown;
  /** Read out to screen readers when the action finishes. */
  doneLabel?: string;
  /** Seconds the tick stays before the label comes back. */
  doneFor?: number;
};

type State = "idle" | "busy" | "done";

/* MorphAction: the pill shrinks into a spinner while the action runs, shows a tick when it is done, then turns back. */
export function MorphAction({
  children,
  className = "bg-[#a78bfa] text-[15px] font-medium text-[#1a1530]",
  onClick,
  doneLabel = "Done",
  doneFor = 1.6,
}: MorphActionProps) {
  const reduce = useReducedMotion();
  const [state, setState] = useState<State>("idle");

  const run = async () => {
    if (state !== "idle") return;
    setState("busy");
    try {
      await onClick?.();
      setState("done");
      setTimeout(() => setState("idle"), doneFor * 1000);
    } catch {
      setState("idle");
    }
  };

  const fade = {
    initial: { opacity: 0, scale: 0.6 },
    animate: { opacity: 1, scale: 1 },
    exit: { opacity: 0, scale: 0.6 },
    transition: { duration: reduce ? 0 : 0.15 },
  };

  return (
    <motion.button
      type="button"
      layout
      onClick={run}
      aria-busy={state === "busy"}
      className={`grid h-14 place-items-center overflow-hidden ${state === "idle" ? "px-9" : "w-14"} ${className}`}
      style={{ borderRadius: 999 }}
      transition={reduce ? { duration: 0 } : { type: "spring", visualDuration: 0.35, bounce: 0.25 }}
    >
      <AnimatePresence mode="wait" initial={false}>
        {state === "idle" && (
          <motion.span key="idle" {...fade} className="whitespace-nowrap">
            {children}
          </motion.span>
        )}
        {state === "busy" && (
          <motion.span key="busy" {...fade} aria-hidden>
            <motion.svg
              viewBox="0 0 24 24"
              className="size-6"
              animate={reduce ? undefined : { rotate: 360 }}
              transition={{ duration: 0.8, repeat: Infinity, ease: "linear" }}
            >
              <circle cx="12" cy="12" r="9" fill="none" stroke="currentColor" strokeWidth="2.5" strokeDasharray="40 60" strokeLinecap="round" />
            </motion.svg>
          </motion.span>
        )}
        {state === "done" && (
          <motion.span key="done" {...fade} aria-hidden>
            <svg viewBox="0 0 24 24" className="size-6">
              <motion.path
                d="M5 12.5l4.5 4.5L19 7.5"
                fill="none"
                stroke="currentColor"
                strokeWidth="2.5"
                strokeLinecap="round"
                strokeLinejoin="round"
                initial={{ pathLength: reduce ? 1 : 0 }}
                animate={{ pathLength: 1 }}
                transition={{ duration: 0.3, delay: 0.1 }}
              />
            </svg>
          </motion.span>
        )}
      </AnimatePresence>
      <span className="sr-only" aria-live="polite">
        {state === "busy" ? "Working" : state === "done" ? doneLabel : ""}
      </span>
    </motion.button>
  );
}