import React, { CSSProperties, useState, useEffect, useRef, useCallback } from 'react';
import { useNode, UserComponent } from '@craftjs/core';
import { cssPropsToString } from '../../utils/style-helpers';
import { escapeHtml, escapeAttr, safeUrl, scopeId, cssValue } from '../../utils/escape';

interface Slide {
  type: 'image' | 'content';
  imageSrc?: string;
  heading?: string;
  text?: string;
  buttonText?: string;
  buttonHref?: string;
  bgColor?: string;
}

interface ContentSliderProps {
  slides?: Slide[];
  autoplay?: boolean;
  interval?: number;
  showDots?: boolean;
  showArrows?: boolean;
  height?: string;
  style?: CSSProperties;
}

const defaultSlides: Slide[] = [
  {
    type: 'image',
    imageSrc: '',
    heading: 'First Slide',
    text: 'Welcome to our showcase',
    buttonText: 'Learn More',
    buttonHref: '#',
    bgColor: 'linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%)',
  },
  {
    type: 'image',
    imageSrc: '',
    heading: 'Second Slide',
    text: 'Discover something amazing',
    buttonText: 'Get Started',
    buttonHref: '#',
    bgColor: 'linear-gradient(135deg, #10b981 0%, #059669 100%)',
  },
  {
    type: 'image',
    imageSrc: '',
    heading: 'Third Slide',
    text: 'Build your future today',
    buttonText: 'Contact Us',
    buttonHref: '#',
    bgColor: 'linear-gradient(135deg, #f59e0b 0%, #ef4444 100%)',
  },
];

export const ContentSlider: UserComponent<ContentSliderProps> = ({
  slides = defaultSlides,
  autoplay = true,
  interval = 5000,
  showDots = true,
  showArrows = true,
  height = '400px',
  style = {},
}) => {
  const {
    connectors: { connect, drag },
    selected,
  } = useNode((node) => ({
    selected: node.events.selected,
  }));

  const [activeIndex, setActiveIndex] = useState(0);
  const timerRef = useRef<ReturnType<typeof setInterval> | null>(null);
  const items = slides.length > 0 ? slides : defaultSlides;

  const goTo = useCallback((index: number) => {
    setActiveIndex(((index % items.length) + items.length) % items.length);
  }, [items.length]);

  const goNext = useCallback(() => goTo(activeIndex + 1), [activeIndex, goTo]);
  const goPrev = useCallback(() => goTo(activeIndex - 1), [activeIndex, goTo]);

  useEffect(() => {
    if (autoplay && items.length > 1) {
      timerRef.current = setInterval(goNext, interval);
      return () => { if (timerRef.current) clearInterval(timerRef.current); };
    }
  }, [autoplay, interval, goNext, items.length]);

  const arrowStyle: CSSProperties = {
    position: 'absolute',
    top: '50%',
    transform: 'translateY(-50%)',
    width: '40px',
    height: '40px',
    borderRadius: '50%',
    border: 'none',
    background: 'rgba(255,255,255,0.9)',
    color: '#18181b',
    fontSize: '16px',
    cursor: 'pointer',
    display: 'flex',
    alignItems: 'center',
    justifyContent: 'center',
    zIndex: 2,
    boxShadow: '0 2px 8px rgba(0,0,0,0.15)',
  };

  const renderSlide = (slide: Slide, i: number) => {
    const bg = slide.imageSrc
      ? { backgroundImage: `url(${slide.imageSrc})`, backgroundSize: 'cover', backgroundPosition: 'center' }
      : slide.bgColor?.startsWith('linear-gradient')
        ? { backgroundImage: slide.bgColor }
        : { backgroundColor: slide.bgColor || '#3b82f6' };

    return (
      <div
        key={i}
        style={{
          position: 'absolute',
          top: 0,
          left: 0,
          width: '100%',
          height: '100%',
          opacity: i === activeIndex ? 1 : 0,
          transition: 'opacity 0.5s ease-in-out',
          display: 'flex',
          flexDirection: 'column',
          alignItems: 'center',
          justifyContent: 'center',
          ...bg,
        }}
      >
        {(slide.heading || slide.text || slide.buttonText) && (
          <div style={{ textAlign: 'center', padding: '20px', zIndex: 1 }}>
            {slide.heading && (
              <h2 style={{ fontSize: '36px', fontWeight: '700', color: '#ffffff', marginBottom: '12px', fontFamily: 'Inter, sans-serif', textShadow: '0 2px 8px rgba(0,0,0,0.3)' }}>
                {slide.heading}
              </h2>
            )}
            {slide.text && (
              <p style={{ fontSize: '18px', color: 'rgba(255,255,255,0.9)', marginBottom: '20px', fontFamily: 'Inter, sans-serif', textShadow: '0 1px 4px rgba(0,0,0,0.3)' }}>
                {slide.text}
              </p>
            )}
            {slide.buttonText && (
              <a
                href={slide.buttonHref || '#'}
                onClick={(e) => e.preventDefault()}
                style={{
                  display: 'inline-block',
                  padding: '12px 28px',
                  background: '#ffffff',
                  color: '#18181b',
                  textDecoration: 'none',
                  borderRadius: '8px',
                  fontWeight: '600',
                  fontSize: '15px',
                  fontFamily: 'Inter, sans-serif',
                }}
              >
                {slide.buttonText}
              </a>
            )}
          </div>
        )}
      </div>
    );
  };

  return (
    <section
      ref={(ref: HTMLElement | null): void => { if (ref) connect(drag(ref)); }}
      style={{
        position: 'relative',
        width: '100%',
        height,
        overflow: 'hidden',
        outline: selected ? '2px solid #3b82f6' : 'none',
        ...style,
      }}
    >
      {items.map((slide, i) => renderSlide(slide, i))}

      {showArrows && items.length > 1 && (
        <>
          <button onClick={goPrev} style={{ ...arrowStyle, left: '16px' }}>
            <i className="fa fa-chevron-left" />
          </button>
          <button onClick={goNext} style={{ ...arrowStyle, right: '16px' }}>
            <i className="fa fa-chevron-right" />
          </button>
        </>
      )}

      {showDots && items.length > 1 && (
        <div style={{ position: 'absolute', bottom: '16px', left: '50%', transform: 'translateX(-50%)', display: 'flex', gap: '8px', zIndex: 2 }}>
          {items.map((_, i) => (
            <button
              key={i}
              onClick={() => goTo(i)}
              style={{
                width: '10px',
                height: '10px',
                borderRadius: '50%',
                border: 'none',
                cursor: 'pointer',
                backgroundColor: i === activeIndex ? '#ffffff' : 'rgba(255,255,255,0.5)',
                transition: 'background-color 0.3s',
              }}
            />
          ))}
        </div>
      )}
    </section>
  );
};

/* ---------- Craft config ---------- */

ContentSlider.craft = {
  displayName: 'Content Slider',
  props: {
    slides: defaultSlides,
    autoplay: true,
    interval: 5000,
    showDots: true,
    showArrows: true,
    height: '400px',
    style: {},
  },
  rules: {
    canDrag: () => true,
    canMoveIn: () => false,
    canMoveOut: () => true,
  },
};

/* ---------- HTML export ---------- */

(ContentSlider as any).toHtml = (props: ContentSliderProps, _childrenHtml: string, nodeId?: string) => {
  const {
    slides = defaultSlides,
    autoplay = true,
    interval = 5000,
    showDots = true,
    showArrows = true,
    height = '400px',
    style = {},
  } = props;

  const items = slides.length > 0 ? slides : defaultSlides;
  // Deterministic AND unique id, scoped on the Craft node id, for this
  // slider's slide/dot element ids and inline-script globals -- so two
  // ContentSlider instances (e.g. both left at default slides) don't
  // collide and end up driving each other's rotation.
  const uid = scopeId(nodeId, JSON.stringify(items) + interval, 'cs');

  const sectionStyle = cssPropsToString({
    position: 'relative',
    width: '100%',
    height,
    overflow: 'hidden',
    ...style,
  });

  const slidesHtml = items.map((slide, i) => {
    const hasBgImage = slide.imageSrc;
    // Sanitized -- slide.bgColor is a per-slide raw string-interpolation
    // sink (a malicious value could break out of the style="..." attribute).
    const safeBgColor = cssValue(slide.bgColor) || '#3b82f6';
    const bgStyle = hasBgImage
      ? `background-image:url('${escapeAttr(safeUrl(slide.imageSrc!))}');background-size:cover;background-position:center`
      : slide.bgColor?.startsWith('linear-gradient')
        ? `background-image:${safeBgColor}`
        : `background-color:${safeBgColor}`;

    const contentParts: string[] = [];
    if (slide.heading) {
      contentParts.push(`<h2 style="font-size:36px;font-weight:700;color:#ffffff;margin-bottom:12px;font-family:Inter,sans-serif;text-shadow:0 2px 8px rgba(0,0,0,0.3)">${escapeHtml(slide.heading)}</h2>`);
    }
    if (slide.text) {
      contentParts.push(`<p style="font-size:18px;color:rgba(255,255,255,0.9);margin-bottom:20px;font-family:Inter,sans-serif;text-shadow:0 1px 4px rgba(0,0,0,0.3)">${escapeHtml(slide.text)}</p>`);
    }
    if (slide.buttonText) {
      contentParts.push(`<a href="${escapeAttr(safeUrl(slide.buttonHref || '#'))}" style="display:inline-block;padding:12px 28px;background:#ffffff;color:#18181b;text-decoration:none;border-radius:8px;font-weight:600;font-size:15px;font-family:Inter,sans-serif">${escapeHtml(slide.buttonText)}</a>`);
    }

    const innerHtml = contentParts.length > 0
      ? `<div style="text-align:center;padding:20px;z-index:1">${contentParts.join('\n      ')}</div>`
      : '';

    return `<div id="${uid}_s${i}" style="position:absolute;top:0;left:0;width:100%;height:100%;opacity:${i === 0 ? 1 : 0};transition:opacity 0.5s ease-in-out;display:flex;flex-direction:column;align-items:center;justify-content:center;${bgStyle}">
      ${innerHtml}
    </div>`;
  }).join('\n  ');

  const arrowsHtml = showArrows && items.length > 1
    ? `<button onclick="${uid}_prev()" aria-label="Previous slide" style="position:absolute;top:50%;left:16px;transform:translateY(-50%);width:40px;height:40px;border-radius:50%;border:none;background:rgba(255,255,255,0.9);color:#18181b;font-size:16px;cursor:pointer;display:flex;align-items:center;justify-content:center;z-index:2;box-shadow:0 2px 8px rgba(0,0,0,0.15)"><i class="fa fa-chevron-left" aria-hidden="true"></i></button>
  <button onclick="${uid}_next()" aria-label="Next slide" style="position:absolute;top:50%;right:16px;transform:translateY(-50%);width:40px;height:40px;border-radius:50%;border:none;background:rgba(255,255,255,0.9);color:#18181b;font-size:16px;cursor:pointer;display:flex;align-items:center;justify-content:center;z-index:2;box-shadow:0 2px 8px rgba(0,0,0,0.15)"><i class="fa fa-chevron-right" aria-hidden="true"></i></button>`
    : '';

  const dotsHtml = showDots && items.length > 1
    ? `<div style="position:absolute;bottom:16px;left:50%;transform:translateX(-50%);display:flex;gap:8px;z-index:2">
    ${items.map((_, i) => `<button onclick="${uid}_go(${i})" id="${uid}_d${i}" aria-label="Go to slide ${i + 1}" style="width:10px;height:10px;border-radius:50%;border:none;cursor:pointer;background-color:${i === 0 ? '#ffffff' : 'rgba(255,255,255,0.5)'};transition:background-color 0.3s"></button>`).join('\n    ')}
  </div>`
    : '';

  // Autoplay ticks call show() directly (internal), while manual nav goes
  // through the exposed window[...] functions -- that split lets us mark
  // the live region "polite" only on manual navigation, and keep it "off"
  // while autoplay is silently auto-rotating, so screen readers aren't
  // spammed with an announcement every `interval` ms (F-export review
  // Minor).
  const autoplayActive = autoplay && items.length > 1;
  const liveAttr = autoplayActive ? 'off' : 'polite';

  return {
    html: `<section id="${uid}"${sectionStyle ? ` style="${sectionStyle}"` : ''}>
  <div id="${uid}_live" aria-live="${liveAttr}">
  ${slidesHtml}
  </div>
  ${arrowsHtml}
  ${dotsHtml}
  <script>
  (function(){
    var current=0, total=${items.length}, uid="${uid}";
    var liveRegion=document.getElementById(uid+"_live");
    function markManualNav(){ if(liveRegion){ liveRegion.setAttribute("aria-live","polite"); } }
    function show(idx){
      document.getElementById(uid+"_s"+current).style.opacity="0";
      ${showDots ? `document.getElementById(uid+"_d"+current).style.backgroundColor="rgba(255,255,255,0.5)";` : ''}
      current=((idx%total)+total)%total;
      document.getElementById(uid+"_s"+current).style.opacity="1";
      ${showDots ? `document.getElementById(uid+"_d"+current).style.backgroundColor="#ffffff";` : ''}
    }
    window["${uid}_go"]=function(idx){ markManualNav(); show(idx); };
    window["${uid}_next"]=function(){ markManualNav(); show(current+1); };
    window["${uid}_prev"]=function(){ markManualNav(); show(current-1); };
    ${autoplayActive ? `
    var timer=null;
    function start(){ if(!timer && document.visibilityState!=="hidden"){ timer=setInterval(function(){show(current+1);},${interval}); } }
    function stop(){ if(timer){ clearInterval(timer); timer=null; } }
    var root=document.getElementById(uid);
    if(root){
      root.addEventListener("mouseenter", stop);
      root.addEventListener("mouseleave", start);
    }
    document.addEventListener("visibilitychange", function(){
      if(document.visibilityState==="hidden"){ stop(); } else { start(); }
    });
    start();
    ` : ''}
  })();
  </script>
</section>`,
  };
};
