import React, { useState } from 'react';
import { ExternalLink } from 'lucide-react';
import { Button } from '@/components/ui/button';
import { Card } from '@/components/ui/card';
import {
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuTrigger,
} from '@/components/ui/dropdown-menu';
import { getConnectorIcon } from './ConnectorComponents';
import { Source } from './types';

type CitationProps = {
  citationId: number;
  citationText: string;
  position: number;
  source: Source | null;
};

/**
 * Citation component to handle individual citations
 */
export const Citation = React.memo(({ citationId, citationText, position, source }: CitationProps) => {
  const [open, setOpen] = useState(false);
  const citationKey = `citation-${citationId}-${position}`;
  
  if (!source) return <>{citationText}</>;
  
  return (
    <span key={citationKey} className="relative inline-flex items-center">
      <DropdownMenu open={open} onOpenChange={setOpen}>
        <DropdownMenuTrigger asChild>
          <sup>
            <span 
              className="inline-flex items-center justify-center text-primary cursor-pointer bg-primary/10 hover:bg-primary/15 w-4 h-4 rounded-full text-[10px] font-medium ml-0.5 transition-colors border border-primary/20 shadow-sm"
            >
              {citationId}
            </span>
          </sup>
        </DropdownMenuTrigger>
        {open && (
          <DropdownMenuContent align="start" className="w-80 p-0" forceMount>
            <Card className="border-0 shadow-none">
              <div className="p-3 flex items-start gap-3">
                <div className="flex-shrink-0 w-7 h-7 flex items-center justify-center bg-muted rounded-full">
                  {getConnectorIcon(source.connectorType || '')}
                </div>
                <div className="flex-1">
                  <div className="flex items-center gap-2 mb-1">
                    <h3 className="font-medium text-sm text-card-foreground">{source.title}</h3>
                  </div>
                  <p className="text-sm text-muted-foreground mt-0.5">{source.description}</p>
                  <div className="mt-2 flex items-center text-xs text-muted-foreground">
                    <span className="truncate max-w-[200px]">{source.url}</span>
                  </div>
                </div>
                <Button 
                  variant="ghost" 
                  size="icon" 
                  className="h-7 w-7 rounded-full"
                  onClick={() => window.open(source.url, '_blank', 'noopener,noreferrer')}
                  title="Open in new tab"
                >
                  <ExternalLink className="h-3.5 w-3.5" />
                </Button>
              </div>
            </Card>
          </DropdownMenuContent>
        )}
      </DropdownMenu>
    </span>
  );
});

Citation.displayName = 'Citation';

/**
 * Function to render text with citations
 */
export const renderTextWithCitations = (text: string, getCitationSource: (id: number) => Source | null) => {
  // Regular expression to find citation patterns like [1], [2], etc.
  const citationRegex = /\[(\d+)\]/g;
  const parts = [];
  let lastIndex = 0;
  let match;
  let position = 0;

  while ((match = citationRegex.exec(text)) !== null) {
    // Add text before the citation
    if (match.index > lastIndex) {
      parts.push(text.substring(lastIndex, match.index));
    }
    
    // Add the citation component
    const citationId = parseInt(match[1], 10);
    parts.push(
      <Citation 
        key={`citation-${citationId}-${position}`}
        citationId={citationId}
        citationText={match[0]}
        position={position}
        source={getCitationSource(citationId)}
      />
    );
    
    lastIndex = match.index + match[0].length;
    position++;
  }
  
  // Add any remaining text after the last citation
  if (lastIndex < text.length) {
    parts.push(text.substring(lastIndex));
  }
  
  return parts;
};