"use client";

import { useEffect, useRef, useCallback } from "react";

interface ConfettiBurstProps {
  trigger: boolean;
  particleCount?: number;
  duration?: number;
  colors?: string[];
}

const DEFAULT_COLORS = [
  "#6366f1", // indigo
  "#8b5cf6", // violet
  "#ec4899", // pink
  "#f59e0b", // amber
  "#10b981", // emerald
  "#3b82f6", // blue
];

const KEYFRAMES_ID = "confetti-burst-keyframes";

function ensureKeyframes() {
  if (typeof document === "undefined") return;
  if (document.getElementById(KEYFRAMES_ID)) return;
  const style = document.createElement("style");
  style.id = KEYFRAMES_ID;
  style.textContent = `
    @keyframes confetti-burst {
      0% {
        transform: translate(0, 0) rotate(0deg) scale(1);
        opacity: 1;
      }
      100% {
        transform: translate(var(--confetti-x), var(--confetti-y)) rotate(var(--confetti-r)) scale(0.3);
        opacity: 0;
      }
    }
  `;
  document.head.appendChild(style);
}

export function ConfettiBurst({
  trigger,
  particleCount = 20,
  duration = 800,
  colors = DEFAULT_COLORS,
}: ConfettiBurstProps) {
  const containerRef = useRef<HTMLDivElement>(null);
  const prevTrigger = useRef(false);

  const burst = useCallback(() => {
    const container = containerRef.current;
    if (!container) return;

    ensureKeyframes();

    const particles: HTMLDivElement[] = [];
    for (let i = 0; i < particleCount; i++) {
      const el = document.createElement("div");
      const angle = (Math.PI * 2 * i) / particleCount + (Math.random() - 0.5) * 0.5;
      const distance = 40 + Math.random() * 80;
      const x = Math.cos(angle) * distance;
      const y = Math.sin(angle) * distance - 20 + Math.random() * 60; // gravity bias
      const rotation = Math.random() * 720 - 360;

      el.style.cssText = `
        position: absolute;
        left: 50%;
        top: 50%;
        width: 6px;
        height: 6px;
        margin: -3px 0 0 -3px;
        border-radius: ${Math.random() > 0.5 ? "50%" : "1px"};
        background: ${colors[i % colors.length]};
        pointer-events: none;
        --confetti-x: ${x}px;
        --confetti-y: ${y}px;
        --confetti-r: ${rotation}deg;
        animation: confetti-burst ${duration}ms cubic-bezier(0.25, 0.46, 0.45, 0.94) forwards;
      `;
      container.appendChild(el);
      particles.push(el);
    }

    setTimeout(() => {
      particles.forEach((el) => el.remove());
    }, duration + 50);
  }, [particleCount, duration, colors]);

  useEffect(() => {
    if (trigger && !prevTrigger.current) {
      burst();
    }
    prevTrigger.current = trigger;
  }, [trigger, burst]);

  return (
    <div
      ref={containerRef}
      className="pointer-events-none absolute inset-0 overflow-visible"
      aria-hidden="true"
    />
  );
}