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

interface AccordionItem {
  title: string;
  content: string;
  isOpen?: boolean;
}

interface AccordionProps {
  items?: AccordionItem[];
  style?: CSSProperties;
  headerBg?: string;
  headerColor?: string;
  contentBg?: string;
  borderColor?: string;
  anchorId?: string;
}

const defaultItems: AccordionItem[] = [
  { title: 'What is this product?', content: 'Our product is a powerful yet easy-to-use tool designed to help you build beautiful websites without writing a single line of code.', isOpen: true },
  { title: 'How do I get started?', content: 'Simply sign up for a free account, choose a template, and start customizing. Our drag-and-drop editor makes it easy to create professional pages in minutes.', isOpen: false },
  { title: 'Is there a free plan?', content: 'Yes! We offer a generous free tier that includes all core features. Upgrade anytime to unlock advanced capabilities like custom domains and analytics.', isOpen: false },
];

export const Accordion: UserComponent<AccordionProps> = ({
  items = defaultItems,
  style = {},
  headerBg = '#f8fafc',
  headerColor = '#18181b',
  contentBg = '#ffffff',
  borderColor = '#e2e8f0',
  anchorId,
}) => {
  const {
    connectors: { connect, drag },
    selected,
  } = useNode((node) => ({
    selected: node.events.selected,
  }));

  const [openIndexes, setOpenIndexes] = useState<Set<number>>(() => {
    const initial = new Set<number>();
    items.forEach((item, i) => { if (item.isOpen) initial.add(i); });
    return initial;
  });

  const toggle = (index: number) => {
    setOpenIndexes((prev) => {
      const next = new Set(prev);
      if (next.has(index)) next.delete(index);
      else next.add(index);
      return next;
    });
  };

  return (
    <section
      ref={(ref: HTMLElement | null): void => { if (ref) connect(drag(ref)); }}
      id={anchorId || undefined}
      style={{
        padding: '60px 20px',
        backgroundColor: '#ffffff',
        outline: selected ? '2px solid #3b82f6' : 'none',
        ...style,
      }}
    >
      <div style={{ maxWidth: '800px', margin: '0 auto', display: 'flex', flexDirection: 'column', gap: '0px' }}>
        {items.map((item, i) => {
          const isOpen = openIndexes.has(i);
          return (
            <div
              key={i}
              style={{
                border: `1px solid ${borderColor}`,
                borderBottom: i === items.length - 1 ? `1px solid ${borderColor}` : 'none',
                ...(i === 0 ? { borderTopLeftRadius: '8px', borderTopRightRadius: '8px' } : {}),
                ...(i === items.length - 1 ? { borderBottomLeftRadius: '8px', borderBottomRightRadius: '8px', borderBottom: `1px solid ${borderColor}` } : {}),
              }}
            >
              <div
                onClick={() => toggle(i)}
                style={{
                  padding: '16px 20px',
                  backgroundColor: headerBg,
                  color: headerColor,
                  cursor: 'pointer',
                  display: 'flex',
                  justifyContent: 'space-between',
                  alignItems: 'center',
                  fontWeight: '600',
                  fontSize: '16px',
                  userSelect: 'none',
                  ...(i === 0 ? { borderTopLeftRadius: '7px', borderTopRightRadius: '7px' } : {}),
                  ...(i === items.length - 1 && !isOpen ? { borderBottomLeftRadius: '7px', borderBottomRightRadius: '7px' } : {}),
                }}
              >
                <span>{item.title}</span>
                <span style={{ fontSize: '12px', transition: 'transform 0.2s', transform: isOpen ? 'rotate(180deg)' : 'rotate(0deg)' }}>&#9660;</span>
              </div>
              {isOpen && (
                <div
                  style={{
                    padding: '16px 20px',
                    backgroundColor: contentBg,
                    color: '#4b5563',
                    fontSize: '14px',
                    lineHeight: '1.6',
                    borderTop: `1px solid ${borderColor}`,
                    ...(i === items.length - 1 ? { borderBottomLeftRadius: '7px', borderBottomRightRadius: '7px' } : {}),
                  }}
                >
                  {item.content}
                </div>
              )}
            </div>
          );
        })}
      </div>
    </section>
  );
};

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

Accordion.craft = {
  displayName: 'Accordion',
  props: {
    items: defaultItems,
    style: { backgroundColor: '#ffffff' },
    headerBg: '#f8fafc',
    headerColor: '#18181b',
    contentBg: '#ffffff',
    borderColor: '#e2e8f0',
    anchorId: '',
  },
  rules: {
    canDrag: () => true,
    canMoveIn: () => false,
    canMoveOut: () => true,
  },
};

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

(Accordion as any).toHtml = (props: AccordionProps, _childrenHtml: string) => {
  const sectionStyle = cssPropsToString({
    padding: '60px 20px',
    ...props.style,
  });
  const idAttr = props.anchorId ? ` id="${escapeAttr(props.anchorId)}"` : '';
  const headerBg = props.headerBg || '#f8fafc';
  const headerColor = props.headerColor || '#18181b';
  const contentBg = props.contentBg || '#ffffff';
  const borderColor = props.borderColor || '#e2e8f0';
  const items = props.items || defaultItems;

  const panels = items.map((item, i) => {
    const openAttr = item.isOpen ? ' open' : '';
    const topRadius = i === 0 ? 'border-top-left-radius:8px;border-top-right-radius:8px;' : '';
    const bottomRadius = i === items.length - 1 ? 'border-bottom-left-radius:8px;border-bottom-right-radius:8px;' : '';
    const borderBottom = i === items.length - 1 ? `border:1px solid ${borderColor};` : `border:1px solid ${borderColor};border-bottom:none;`;
    return `<details${openAttr} style="${borderBottom}${topRadius}${bottomRadius}">
      <summary style="padding:16px 20px;background-color:${headerBg};color:${headerColor};cursor:pointer;font-weight:600;font-size:16px;list-style:none;display:flex;justify-content:space-between;align-items:center">
        ${escapeHtml(item.title)}
      </summary>
      <div style="padding:16px 20px;background-color:${contentBg};color:#4b5563;font-size:14px;line-height:1.6;border-top:1px solid ${borderColor}">
        ${escapeHtml(item.content)}
      </div>
    </details>`;
  }).join('\n    ');

  return {
    html: `<section${idAttr}${sectionStyle ? ` style="${sectionStyle}"` : ''}>
  <div style="max-width:800px;margin:0 auto;display:flex;flex-direction:column">
    ${panels}
  </div>
  <style>details summary::-webkit-details-marker{display:none}details summary::marker{display:none}</style>
</section>`,
  };
};