import React, { useState, useEffect, useRef } from 'react';
import { createPortal } from 'react-dom';
import { Calendar, Tag, ChevronRight, X, User } from "lucide-react";
import { colors } from "../../theme/colors";
import { API_BASE_URL } from '../../config/api';
import branding from '../../branding';

const AnnouncementModal = ({ announcement, onClose }) => {
  const dialogRef = useRef(null);

  useEffect(() => {
    const previousOverflow = document.body.style.overflow;
    const previousFocus = document.activeElement;
    const handleKeyDown = (event) => {
      if (event.key === 'Escape') onClose();
      if (event.key !== 'Tab' || !dialogRef.current) return;
      const controls = dialogRef.current.querySelectorAll('button, a[href], input, select, textarea, [tabindex]:not([tabindex="-1"])');
      if (!controls.length) return;
      const first = controls[0];
      const last = controls[controls.length - 1];
      if (event.shiftKey && document.activeElement === first) {
        event.preventDefault();
        last.focus();
      } else if (!event.shiftKey && document.activeElement === last) {
        event.preventDefault();
        first.focus();
      }
    };

    document.body.style.overflow = 'hidden';
    document.addEventListener('keydown', handleKeyDown);
    dialogRef.current?.focus();
    return () => {
      document.body.style.overflow = previousOverflow;
      document.removeEventListener('keydown', handleKeyDown);
      previousFocus?.focus?.();
    };
  }, [onClose]);

  if (!announcement) return null;

  const getTagColor = (tag) => {
    const lowerTag = tag.toLowerCase();
    if (lowerTag.includes('update') || lowerTag.includes('feature')) return colors.green;
    if (lowerTag.includes('alert') || lowerTag.includes('maintenance') || lowerTag.includes('downtime')) return colors.red;
    if (lowerTag.includes('technical') || lowerTag.includes('info')) return colors.blue;
    return colors.yellow;
  };

  const formatDate = (dateString) => {
    try {
      const date = new Date(dateString);
      return date.toLocaleDateString('en-US', {
        year: 'numeric',
        month: 'long',
        day: 'numeric',
        hour: '2-digit',
        minute: '2-digit'
      });
    } catch (e) {
      return dateString;
    }
  };

  return createPortal(
    <div className="announcement-overlay">
      <div ref={dialogRef} className="announcement-dialog" role="dialog" aria-modal="true" aria-labelledby="announcement-title" tabIndex={-1}>
        {/* Header */}
        <div className="announcement-dialog-header">
          <div className="flex-1 pr-8">
            <div className="flex flex-wrap gap-2 mb-4">
              {announcement.tags && announcement.tags.map((tag, idx) => {
                const tagColor = getTagColor(tag);
                return (
                  <span 
                    key={idx} 
                    className="announcement-tag"
                    style={{ backgroundColor: `${tagColor}20`, color: tagColor, border: `1px solid ${tagColor}30` }}
                  >
                    <Tag className="w-3 h-3 mr-1.5" />
                    {tag}
                  </span>
                );
              })}
            </div>
            <h2 id="announcement-title" className="text-2xl sm:text-3xl font-semibold leading-tight">
              {announcement.title}
            </h2>
          </div>
          <button 
            onClick={onClose}
            className="announcement-close"
            aria-label="Close announcement"
          >
            <X className="w-6 h-6" />
          </button>
        </div>

        {/* Content */}
        <div className="announcement-dialog-content">
          <div className="announcement-meta">
            <div className="flex items-center">
              <Calendar className="w-4 h-4 mr-2" aria-hidden />
              {formatDate(announcement.created_at)}
            </div>
            <div className="flex items-center">
              <User className="w-4 h-4 mr-2" aria-hidden />
              Posted by <span className="font-semibold ml-1.5">{announcement.author_name || 'Administrator'}</span>
            </div>
          </div>

          <div 
            className="announcement-body"
            style={{ fontFamily: 'inherit' }}
          >
            {announcement.content}
          </div>
        </div>

        {/* Footer */}
        <div className="announcement-dialog-footer">
          <button 
            onClick={onClose}
            className="site-button site-button--primary"
          >
            Close Announcement
          </button>
        </div>
      </div>
    </div>,
    document.body
  );
};

const AnnouncementsSection = () => {
  const [announcements, setAnnouncements] = useState([]);
  const [isLoading, setIsLoading] = useState(true);
  const [error, setError] = useState(null);
  const [selectedAnnouncement, setSelectedAnnouncement] = useState(null);
  const [showAll, setShowAll] = useState(false);

  useEffect(() => {
    const fetchAnnouncements = async () => {
      try {
        const response = await fetch(`${API_BASE_URL}/api/announcements?limit=20`);
        if (!response.ok) {
          throw new Error('Failed to fetch announcements');
        }
        const data = await response.json();
        if (data.success) {
          setAnnouncements(data.announcements);
        } else {
          throw new Error(data.error || 'Unknown error');
        }
      } catch (err) {
        console.error('Error fetching announcements:', err);
        setError('Could not load latest news.');
      } finally {
        setIsLoading(false);
      }
    };

    fetchAnnouncements();
  }, []);

  const formatDate = (dateString) => {
    try {
      const date = new Date(dateString);
      return date.toLocaleDateString('en-US', {
        month: 'short',
        day: 'numeric',
        year: 'numeric'
      });
    } catch (e) {
      return dateString;
    }
  };

  const displayedAnnouncements = showAll ? announcements : announcements.slice(0, 3);

  if (isLoading) {
    return (
      <section className="site-section site-announcements" aria-busy="true" aria-label="Loading announcements">
        <div className="site-section-heading"><div><p className="site-kicker">Updates</p><h2>Latest announcements.</h2></div></div>
        <div className="site-announcement-list">
          {[1, 2, 3].map((item) => <div key={item} className="site-announcement-skeleton" />)}
        </div>
      </section>
    );
  }

  if (error || announcements.length === 0) return null;

  return (
    <section id="announcements" className="site-section site-announcements">
      <div className="site-section-heading">
        <div><p className="site-kicker">Platform updates</p><h2>Latest announcements.</h2></div>
        <p>Service changes and notes from the {branding.name} team.</p>
      </div>
      <div className="site-announcement-list">
        {displayedAnnouncements.map((item) => (
          <button key={item.id} type="button" className="site-announcement-item" onClick={() => setSelectedAnnouncement(item)}>
            <span className="site-announcement-meta">
              <span>{formatDate(item.created_at)}</span>
              {item.tags?.[0] && <span className="site-announcement-tag">{item.tags[0]}</span>}
            </span>
            <span className="site-announcement-title">{item.title}</span>
            <span className="site-announcement-summary">{item.content}</span>
            <span className="site-announcement-open">Read announcement <ChevronRight size={16} aria-hidden /></span>
          </button>
        ))}
      </div>

      {announcements.length > 3 && (
        <button type="button" className="site-button site-button--quiet site-announcement-more" onClick={() => setShowAll((value) => !value)}>
          {showAll ? 'Show fewer updates' : `Show all ${announcements.length} updates`}
        </button>
      )}

      {/* Modal Overlay */}
      {selectedAnnouncement && (
        <AnnouncementModal 
          announcement={selectedAnnouncement} 
          onClose={() => setSelectedAnnouncement(null)} 
        />
      )}

    </section>
  );
};

export default AnnouncementsSection;