"use client";

import { useEffect, useState } from "react";
import { ChevronLeft, ChevronRight } from "lucide-react";
import { Placeholder } from "@/components/Placeholder";
import { SlotLink } from "@/components/SlotLink";
import { parseAspectRatio } from "@/lib/static-images";
import type { SlotMediaItem } from "@/lib/static-images";

function circularOffset(index: number, active: number, length: number) {
  let diff = index - active;
  if (diff > length / 2) diff -= length;
  if (diff < -length / 2) diff += length;
  return diff;
}

const slideWidth = "min(1280px, calc(100vw - 5rem))";

export function Hero({ slides, aspectRatio }: { slides: SlotMediaItem[]; aspectRatio?: string }) {
  const [active, setActive] = useState(0);
  const [paused, setPaused] = useState(false);
  const ratio = parseAspectRatio(aspectRatio);

  useEffect(() => {
    setActive(0);
  }, [slides.length]);

  useEffect(() => {
    if (slides.length < 2 || paused) return;
    const timer = setInterval(() => {
      setActive((current) => (current + 1) % slides.length);
    }, 6000);
    return () => clearInterval(timer);
  }, [paused, slides.length]);

  const go = (direction: number) => {
    if (slides.length < 2) return;
    setActive((current) => (current + direction + slides.length) % slides.length);
  };

  if (slides.length === 0) return null;

  return (
    <section className="relative overflow-x-clip bg-white pt-5 pb-8">
      <div
        className={ratio ? "relative min-h-[340px]" : "relative h-[min(62vh,640px)] min-h-[340px]"}
        style={ratio ? { aspectRatio: ratio, maxHeight: 640 } : undefined}
        dir="ltr"
        onMouseEnter={() => setPaused(true)}
        onMouseLeave={() => setPaused(false)}
      >
        {slides.map((item, i) => {
          const offset = circularOffset(i, active, slides.length);
          const isCenter = offset === 0;
          const isPeek = Math.abs(offset) === 1;

          return (
            <article
              key={item.id}
              className="absolute top-0 h-full w-[min(1280px,calc(100vw-5rem))]"
              style={{
                left: `calc(50% - (${slideWidth}) / 2 + ${offset} * ((${slideWidth}) + 1rem))`,
                zIndex: isCenter ? 3 : isPeek ? 2 : 1,
                opacity: isCenter || isPeek ? 1 : 0,
                pointerEvents: isCenter || isPeek ? "auto" : "none",
                transition: "left 700ms cubic-bezier(0.22, 1, 0.36, 1), opacity 500ms ease",
              }}
            >
              {isCenter ? (
                <SlotLink href={item.href} className="relative block h-full overflow-hidden rounded-2xl">
                  <Placeholder
                    src={item.image}
                    fallbackSrc={item.fallbackSrc}
                    alt={item.title ?? ""}
                    className="h-full w-full object-cover"
                  />
                  <div
                    className="absolute inset-x-4 bottom-4 z-10 rounded-2xl px-5 py-3.5 sm:inset-x-5 sm:bottom-5 sm:px-7 sm:py-4"
                    style={{
                      background:
                        "linear-gradient(180deg, rgb(48 52 56 / 0.72) 0%, rgb(18 20 22 / 0.82) 100%)",
                      backdropFilter: "blur(22px) saturate(180%)",
                      WebkitBackdropFilter: "blur(22px) saturate(180%)",
                      border: "1px solid rgb(255 255 255 / 0.22)",
                      boxShadow:
                        "inset 0 1px 0 rgb(255 255 255 / 0.28), 0 10px 28px rgb(0 0 0 / 0.28)",
                    }}
                  >
                    <div dir="rtl" className="flex items-center justify-between gap-4">
                      <div className="flex min-w-0 items-center gap-3 sm:gap-5">
                        <h1 className="truncate text-[16px] font-extrabold text-white sm:text-[22px]">
                          {item.title}
                        </h1>
                        <span className="hidden h-[3px] w-10 shrink-0 rounded-full bg-brand sm:block" />
                        <span className="hidden h-6 w-px shrink-0 bg-white/20 sm:block" />
                        {item.kicker ? (
                          <p className="font-latin hidden shrink-0 text-[11px] tracking-[0.2em] text-white/60 uppercase sm:block">
                            {item.kicker}
                          </p>
                        ) : null}
                      </div>
                      <span className="inline-flex shrink-0 rounded-xl bg-brand px-5 py-2.5 text-[13px] font-medium text-white sm:px-6 sm:py-3 sm:text-[14px]">
                        مشاهده قطعات
                      </span>
                    </div>
                  </div>
                </SlotLink>
              ) : (
                <button
                  type="button"
                  className="relative block h-full w-full overflow-hidden rounded-2xl"
                  onClick={() => setActive(i)}
                  aria-label={item.title}
                >
                  <Placeholder src={item.image} fallbackSrc={item.fallbackSrc} alt="" className="h-full w-full object-cover" />
                  <span className="absolute inset-0 bg-white/35" />
                </button>
              )}
            </article>
          );
        })}

        <div className="pointer-events-none absolute inset-y-0 left-1/2 z-10 w-[min(1280px,calc(100vw-5rem))] -translate-x-1/2">
          <button
            type="button"
            onClick={() => go(1)}
            className="pointer-events-auto absolute top-1/2 right-3 grid size-11 -translate-y-1/2 place-items-center rounded-full bg-white text-ink shadow-sm"
            aria-label="اسلاید راست"
          >
            <ChevronRight className="size-5" />
          </button>
          <button
            type="button"
            onClick={() => go(-1)}
            className="pointer-events-auto absolute top-1/2 left-3 grid size-11 -translate-y-1/2 place-items-center rounded-full bg-white text-ink shadow-sm"
            aria-label="اسلاید چپ"
          >
            <ChevronLeft className="size-5" />
          </button>
        </div>
      </div>

      <div className="relative z-10 mt-5 flex justify-center gap-2">
        {slides.map((item, i) => (
          <button
            key={item.id}
            type="button"
            onClick={() => setActive(i)}
            className={`h-1.5 rounded-full transition-all ${i === active ? "w-8 bg-brand" : "w-3 bg-ink/20"}`}
            aria-label={`اسلاید ${i + 1}`}
          />
        ))}
      </div>
    </section>
  );
}