'use client';

import {
  BriefcaseBusiness,
  Check,
  Copy,
  Mail,
  MessageCircle,
  Send,
  Share2,
  X,
} from 'lucide-react';
import {
  useCallback,
  useEffect,
  useRef,
  useState,
  type MouseEvent,
} from 'react';
import { messagesByLocale, type Locale } from '@/i18n/content';
import styles from './CaseStudyDrawer.module.css';

type CopyState = 'idle' | 'copied' | 'error';

export function CaseStudyShare({ locale }: { locale: Locale }) {
  const copy = messagesByLocale[locale].projects;
  const triggerRef = useRef<HTMLButtonElement>(null);
  const dialogRef = useRef<HTMLDialogElement>(null);
  const closeRef = useRef<HTMLButtonElement>(null);
  const skipMotionRef = useRef(false);
  const [fallbackOpen, setFallbackOpen] = useState(false);
  const [copyState, setCopyState] = useState<CopyState>('idle');
  const [shareData, setShareData] = useState({ title: '', url: '' });

  useEffect(() => {
    const dialog = dialogRef.current;
    if (!dialog) return;

    if (fallbackOpen && !dialog.open) {
      dialog.dataset.motion = skipMotionRef.current ? 'none' : 'standard';
      dialog.showModal();
      requestAnimationFrame(() => {
        dialog.dataset.state = 'open';
        closeRef.current?.focus();
      });
    }

    if (!fallbackOpen && dialog.open) dialog.close();
  }, [fallbackOpen]);

  const openFallback = useCallback((skipMotion: boolean) => {
    skipMotionRef.current = skipMotion;
    setCopyState('idle');
    setShareData({ title: document.title, url: window.location.href });
    setFallbackOpen(true);
  }, []);

  const closeFallback = useCallback(() => {
    const dialog = dialogRef.current;
    if (!dialog?.open) return;
    const reduceMotion = window.matchMedia('(prefers-reduced-motion: reduce)').matches;
    if (reduceMotion || dialog.dataset.motion === 'none') {
      dialog.close();
      setFallbackOpen(false);
      triggerRef.current?.focus({ preventScroll: true });
      return;
    }

    dialog.dataset.state = 'closing';
    window.setTimeout(() => {
      dialog.close();
      setFallbackOpen(false);
      triggerRef.current?.focus({ preventScroll: true });
    }, 140);
  }, []);

  const handleShare = async (event: MouseEvent<HTMLButtonElement>) => {
    const data = { title: document.title, url: window.location.href };
    const useNativeShare = window.matchMedia('(max-width: 1100px)').matches
      && typeof navigator.share === 'function';

    if (useNativeShare) {
      try {
        await navigator.share(data);
        return;
      } catch (error) {
        if (error instanceof DOMException && error.name === 'AbortError') return;
      }
    }

    openFallback(event.detail === 0);
  };

  const copyCurrentLink = async () => {
    try {
      await navigator.clipboard.writeText(shareData.url);
      setCopyState('copied');
    } catch {
      setCopyState('error');
    }
  };

  const encodedUrl = encodeURIComponent(shareData.url);
  const encodedTitle = encodeURIComponent(shareData.title);
  const encodedMessage = encodeURIComponent(`${shareData.title} ${shareData.url}`);
  const feedback = copyState === 'copied' ? copy.linkCopied : copyState === 'error' ? copy.copyFailed : '';

  return (
    <>
      <button
        ref={triggerRef}
        type="button"
        className={styles.actionButton}
        onClick={handleShare}
        aria-label={copy.shareCaseStudy}
        aria-haspopup="dialog"
      >
        <Share2 size={19} aria-hidden="true" />
        <span className={styles.actionText}>{copy.shareLabel}</span>
      </button>

      <dialog
        ref={dialogRef}
        className={styles.shareDialog}
        aria-labelledby="case-study-share-title"
        aria-describedby="case-study-share-description"
        data-state="opening"
        onCancel={(event) => {
          event.preventDefault();
          closeFallback();
        }}
        onClick={(event) => {
          if (event.target === event.currentTarget) closeFallback();
        }}
      >
        <section className={styles.sharePanel} onClick={(event) => event.stopPropagation()}>
          <header className={styles.shareHeader}>
            <div>
              <h2 id="case-study-share-title">{copy.shareDialogTitle}</h2>
              <p id="case-study-share-description">{copy.shareDialogDescription}</p>
            </div>
            <button ref={closeRef} type="button" className={styles.iconButton} onClick={closeFallback} aria-label={copy.closeShareDialog}>
              <X size={21} aria-hidden="true" />
            </button>
          </header>

          <div className={styles.shareOptions}>
            <a href={`https://t.me/share/url?url=${encodedUrl}&text=${encodedTitle}`} target="_blank" rel="noopener noreferrer">
              <Send aria-hidden="true" /><span>{copy.shareTelegram}</span>
            </a>
            <a href={`https://wa.me/?text=${encodedMessage}`} target="_blank" rel="noopener noreferrer">
              <MessageCircle aria-hidden="true" /><span>{copy.shareWhatsApp}</span>
            </a>
            <a href={`https://www.linkedin.com/sharing/share-offsite/?url=${encodedUrl}`} target="_blank" rel="noopener noreferrer">
              <BriefcaseBusiness aria-hidden="true" /><span>{copy.shareLinkedIn}</span>
            </a>
            <a href={`mailto:?subject=${encodedTitle}&body=${encodedMessage}`}>
              <Mail aria-hidden="true" /><span>{copy.shareEmail}</span>
            </a>
          </div>

          <button type="button" className={styles.copyLinkButton} onClick={copyCurrentLink}>
            {copyState === 'copied' ? <Check aria-hidden="true" /> : <Copy aria-hidden="true" />}
            <span>{copyState === 'copied' ? copy.linkCopied : copy.copyLink}</span>
          </button>
          <span className={styles.liveRegion} aria-live="polite">{feedback}</span>
        </section>
      </dialog>
    </>
  );
}