import React, {useEffect, useId, useRef, useState} from 'react';
import useBaseUrl from '@docusaurus/useBaseUrl';
import {useLocation} from '@docusaurus/router';
import {useColorMode} from '@docusaurus/theme-common';

export default function ArchifyDiagram({name, title, compact = false, story = false}: {name: string; title: string; compact?: boolean; story?: boolean}): React.ReactElement {
  if (!/^[a-z0-9]+(?:-[a-z0-9]+)*$/.test(name)) throw new Error('Invalid diagram name');
  const source = useBaseUrl(`/diagrams/${name}/`);
  const mobileSource = useBaseUrl(`/diagrams/${name}-mobile/`);
  const dialog = useRef<HTMLDialogElement>(null);
  const opener = useRef<HTMLButtonElement>(null);
  const headingId = useId();
  const [expanded, setExpanded] = useState(false);
  const [narrowRoadmap, setNarrowRoadmap] = useState(false);
  useEffect(() => {
    if (name !== 'strategy-roadmap') return;
    const media = window.matchMedia('(max-width: 999px)');
    const update = () => setNarrowRoadmap(media.matches);
    update();
    media.addEventListener('change', update);
    return () => media.removeEventListener('change', update);
  }, [name]);
  const {colorMode, setColorMode} = useColorMode();
  const initialTheme = useRef(colorMode);
  const desktop = useRef<HTMLIFrameElement>(null);
  const mobile = useRef<HTMLIFrameElement>(null);
  const fullscreen = useRef<HTMLIFrameElement>(null);
  const syncTheme = (frame: HTMLIFrameElement | null) => frame?.contentWindow?.postMessage({type: 'eldorado:set-theme', theme: colorMode}, '*');
  useEffect(() => {
    for (const frame of [desktop, mobile, fullscreen]) syncTheme(frame.current);
    const receiveTheme = (event: MessageEvent) => {
      if (!event.source || ![desktop, mobile, fullscreen].some(frame => frame.current?.contentWindow === event.source)) return;
      if (event.data?.type !== 'eldorado:theme' || !['light', 'dark'].includes(event.data.theme)) return;
      if (event.data.theme !== colorMode) setColorMode(event.data.theme);
    };
    window.addEventListener('message', receiveTheme);
    return () => window.removeEventListener('message', receiveTheme);
  }, [colorMode, setColorMode, expanded]);
  const {pathname, hash} = useLocation();
  useEffect(() => {
    if (!story || !hash) return;
    let id: string;
    try {id = decodeURIComponent(hash.slice(1));} catch {return;}
    const frame = requestAnimationFrame(() => {
      const target = document.getElementById(id);
      if (!target?.closest('.strategy-content')) return;
      let detail = target.closest('details');
      if (!detail) return;
      while (detail) {
        if (detail.dataset.collapsed === 'true') {
          detail.querySelector<HTMLElement>(':scope > summary')?.click();
        } else if (!detail.hasAttribute('data-collapsed')) {
          detail.open = true;
        }
        detail = detail.parentElement?.closest('details') ?? null;
      }
      target.scrollIntoView();
    });
    return () => cancelAnimationFrame(frame);
  }, [story, pathname, hash]);
  useEffect(() => {
    if (!expanded) return;
    dialog.current?.showModal();
    const previousOverflow = document.body.style.overflow;
    document.body.style.overflow = 'hidden';
    return () => {document.body.style.overflow = previousOverflow;};
  }, [expanded]);
  const close = () => {dialog.current?.close();};
  return <section className={`archify-panel${compact ? ' archify-panel--compact' : ''}${story ? ' archify-panel--story' : ''}`} data-diagram={name} aria-label={title}>
    <div className="archify-toolbar"><button ref={opener} type="button" className="archify-expand" aria-label={`Expand ${title}`} title="Expand diagram" onClick={() => setExpanded(true)}><svg width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" strokeWidth="2" aria-hidden="true"><path d="M8 3H3v5M16 3h5v5M21 16v5h-5M8 21H3v-5" /></svg></button></div>
    {story ? <>
      <iframe className="story-desktop" ref={desktop} onLoad={() => syncTheme(desktop.current)} src={`${source}?embed=1&theme=${initialTheme.current}`} title={title} sandbox="allow-scripts allow-downloads" loading="lazy" referrerPolicy="no-referrer" />
      <iframe className="story-mobile" ref={mobile} onLoad={() => syncTheme(mobile.current)} src={`${mobileSource}?embed=1&theme=${initialTheme.current}`} title={`${title} — narrow layout`} sandbox="allow-scripts allow-downloads" loading="lazy" referrerPolicy="no-referrer" />
    </> : <iframe ref={desktop} onLoad={() => syncTheme(desktop.current)} src={`${source}?theme=${initialTheme.current}`} title={title} sandbox="allow-scripts allow-downloads" loading="lazy" referrerPolicy="no-referrer" />}
    <dialog ref={dialog} className="archify-modal" aria-labelledby={headingId} onClose={() => {setExpanded(false); opener.current?.focus();}}>
      <div className="archify-modal-toolbar"><strong id={headingId}>{title}</strong><button type="button" onClick={close} autoFocus aria-label="Close full-screen diagram"><span aria-hidden="true">×</span></button></div>
      {expanded && <iframe ref={fullscreen} onLoad={() => syncTheme(fullscreen.current)} src={`${narrowRoadmap ? mobileSource : source}?${name === 'strategy-roadmap' ? 'embed=1&' : ''}theme=${initialTheme.current}`} title={`${title} — expanded`} sandbox="allow-scripts allow-downloads" referrerPolicy="no-referrer" />}
    </dialog>
  </section>;
}