import { useState } from "react";
import { useQuery, useMutation } from "@tanstack/react-query";
import { useRoute, useLocation } from "wouter";
import { Button } from "@/components/ui/button";
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card";
import { Badge } from "@/components/ui/badge";
import { Input } from "@/components/ui/input";
import { TrendingUp, TrendingDown, DollarSign, Clock } from "lucide-react";
import { useToast } from "@/hooks/use-toast";
import { apiRequest, queryClient } from "@/lib/queryClient";
import Footer from "@/components/Footer";
import type { Article, PredictionMarket } from "@shared/schema";

export default function Article() {
  const [, params] = useRoute("/articles/:slug");
  const [, setLocation] = useLocation();
  const { toast } = useToast();
  const [betAmounts, setBetAmounts] = useState<Record<string, string>>({});

  const { data: article, isLoading: articleLoading } = useQuery<Article>({
    queryKey: ["/api/articles", params?.slug],
    enabled: !!params?.slug
  });

  const { data: markets = [], isLoading: marketsLoading } = useQuery<PredictionMarket[]>({
    queryKey: ["/api/articles", params?.slug, "markets"],
    enabled: !!params?.slug
  });

  const placeBetMutation = useMutation({
    mutationFn: async ({ marketId, side, amount }: { marketId: string; side: "yes" | "no"; amount: number }) => {
      return apiRequest("POST", `/api/prediction-markets/${marketId}/bets`, { side, amount });
    },
    onSuccess: () => {
      toast({
        title: "Bet Placed Successfully",
        description: "Your prediction market bet has been placed."
      });
      queryClient.invalidateQueries({ queryKey: ["/api/articles", params?.slug, "markets"] });
      setBetAmounts({});
    },
    onError: (error: any) => {
      toast({
        title: "Bet Failed",
        description: error.message || "An error occurred while placing your bet.",
        variant: "destructive"
      });
    }
  });

  const formatCurrency = (amount: string | number | null) => {
    if (!amount) return '₩0';
    return new Intl.NumberFormat('ko-KR', {
      style: 'currency',
      currency: 'KRW'
    }).format(Number(amount));
  };

  const formatPercentage = (value: string | number | null) => {
    if (!value) return '0.0%';
    return `${(Number(value) * 100).toFixed(1)}%`;
  };

  const formatDate = (dateString: string | Date | null) => {
    if (!dateString) return '미정';
    return new Intl.DateTimeFormat('ko-KR', {
      year: 'numeric',
      month: 'long',
      day: 'numeric',
      hour: '2-digit',
      minute: '2-digit'
    }).format(new Date(dateString));
  };

  const handleBetAmountChange = (marketId: string, value: string) => {
    setBetAmounts(prev => ({
      ...prev,
      [marketId]: value
    }));
  };

  const handlePlaceBet = (marketId: string, side: "yes" | "no") => {
    // Default bet amount (can be customized later)
    const amount = 10000;
    placeBetMutation.mutate({ marketId, side, amount });
  };

  const parseArticleContent = (content: string) => {
    const sectionRegex = /##SECTION##(.+?)##/g;
    const parts: { type: 'section' | 'text'; content: string }[] = [];
    let lastIndex = 0;
    let match;

    while ((match = sectionRegex.exec(content)) !== null) {
      if (match.index > lastIndex) {
        parts.push({ type: 'text', content: content.slice(lastIndex, match.index) });
      }
      parts.push({ type: 'section', content: match[1] });
      lastIndex = match.index + match[0].length;
    }

    if (lastIndex < content.length) {
      parts.push({ type: 'text', content: content.slice(lastIndex) });
    }

    return parts;
  };

  if (articleLoading) {
    return (
      <div className="min-h-screen bg-gray-50">
        <header className="bg-white border-b border-gray-200 sticky top-0 z-50">
          <div className="max-w-7xl mx-auto px-6 py-4">
            <div className="flex items-center justify-between">
              <div className="flex items-center">
                <img 
                  src="/attached_assets/logo_black_1759181850935.png" 
                  alt="SAPIENS" 
                  className="h-5 w-auto cursor-pointer"
                  data-testid="logo-sapiens"
                  onClick={() => setLocation("/")}
                />
              </div>
            </div>
          </div>
        </header>

        <main className="max-w-7xl mx-auto px-6 py-8">
          <div className="animate-pulse">
            <div className="h-8 bg-gray-300 rounded mb-4 w-3/4"></div>
            <div className="h-4 bg-gray-300 rounded mb-6 w-1/2"></div>
            <div className="h-64 bg-gray-300 rounded mb-6"></div>
            <div className="space-y-2">
              <div className="h-4 bg-gray-300 rounded"></div>
              <div className="h-4 bg-gray-300 rounded"></div>
              <div className="h-4 bg-gray-300 rounded w-3/4"></div>
            </div>
          </div>
        </main>
      </div>
    );
  }

  if (!article) {
    return (
      <div className="min-h-screen bg-gray-50 flex items-center justify-center">
        <div className="text-center">
          <h1 className="text-2xl font-bold mb-4">기사를 찾을 수 없습니다</h1>
          <Button onClick={() => setLocation("/")}>홈으로 돌아가기</Button>
        </div>
      </div>
    );
  }

  return (
    <div className="min-h-screen bg-gray-50">
      {/* Header */}
      <header className="bg-white border-b border-gray-200 sticky top-0 z-50">
        <div className="max-w-7xl mx-auto px-6 py-4">
          <div className="flex items-center justify-between">
            <div className="flex items-center">
              <img 
                src="/attached_assets/logo_black_1759181850935.png" 
                alt="SAPIENS" 
                className="h-5 w-auto cursor-pointer"
                data-testid="logo-sapiens"
                onClick={() => setLocation("/")}
              />
            </div>
          </div>
        </div>
      </header>

      <main className="max-w-7xl mx-auto px-6 py-12">
        {/* Article Content */}
        <article className="mb-16 max-w-4xl mx-auto">
          <header className="mb-8">
            <h1 className="text-4xl font-bold mb-4 text-gray-900 leading-tight" data-testid="text-article-title">{article.title}</h1>
            {article.excerpt && (
              <p className="text-lg text-gray-600 mb-0 leading-relaxed" data-testid="text-article-excerpt">
                {article.excerpt}
              </p>
            )}
          </header>

          <div 
            className="text-base text-gray-800"
            data-testid="text-article-content"
          >
            {parseArticleContent(article.content).map((part, index) => {
              if (part.type === 'section') {
                return (
                  <h3 
                    key={index} 
                    className="text-lg font-bold mt-10 mb-4 text-gray-900"
                  >
                    {part.content.trim()}
                  </h3>
                );
              }
              return (
                <p key={index} className="mb-4 whitespace-pre-wrap leading-loose">
                  {part.content.trim()}
                </p>
              );
            })}
          </div>
        </article>

        {/* Prediction Markets Section */}
        <section className="max-w-4xl mx-auto">
          <h2 className="text-xl font-bold mb-6">Related Prediction Markets</h2>

          {marketsLoading ? (
            <div className="space-y-4">
              {Array.from({ length: 3 }).map((_, i) => (
                <Card key={i} className="animate-pulse">
                  <CardContent className="p-6">
                    <div className="h-6 bg-gray-300 rounded mb-4 w-3/4"></div>
                    <div className="grid grid-cols-2 gap-4">
                      <div className="h-20 bg-gray-300 rounded"></div>
                      <div className="h-20 bg-gray-300 rounded"></div>
                    </div>
                  </CardContent>
                </Card>
              ))}
            </div>
          ) : markets.length > 0 ? (
            <div className="space-y-4">
              {markets.map((market) => (
                <Card key={market.id} className="border border-gray-200">
                  <CardContent className="p-6">
                    {/* Question and Live Badge */}
                    <div className="flex items-start justify-between mb-6">
                      <h3 className="text-base font-medium flex-1 pr-4" data-testid={`text-market-question-${market.id}`}>
                        {market.question}
                      </h3>
                      {market.isActive && (
                        <Badge className="bg-red-500 text-white text-xs px-2 py-0.5 shrink-0">
                          LIVE
                        </Badge>
                      )}
                    </div>

                    {/* Percentages */}
                    <div className="flex items-center justify-between mb-6">
                      <div className="text-left">
                        <div className="text-4xl font-bold" data-testid={`text-yes-price-${market.id}`}>
                          {formatPercentage(market.yesPrice)}
                        </div>
                        <div className="text-sm text-gray-500 mt-1">YES</div>
                      </div>
                      <div className="text-right">
                        <div className="text-4xl font-bold" data-testid={`text-no-price-${market.id}`}>
                          {formatPercentage(market.noPrice)}
                        </div>
                        <div className="text-sm text-gray-500 mt-1">NO</div>
                      </div>
                    </div>

                    {/* Yes/No Buttons */}
                    <div className="grid grid-cols-2 gap-3 mb-6">
                      <Button 
                        variant="outline"
                        className="w-full border-gray-300 hover:bg-gray-50"
                        onClick={() => handlePlaceBet(market.id, "yes")}
                        disabled={placeBetMutation.isPending}
                        data-testid={`button-bet-yes-${market.id}`}
                      >
                        Yes
                      </Button>
                      <Button 
                        variant="outline"
                        className="w-full border-gray-300 hover:bg-gray-50"
                        onClick={() => handlePlaceBet(market.id, "no")}
                        disabled={placeBetMutation.isPending}
                        data-testid={`button-bet-no-${market.id}`}
                      >
                        No
                      </Button>
                    </div>

                    {/* Market Info */}
                    <div className="flex items-center justify-between text-sm text-gray-500 pt-4 border-t border-gray-200">
                      <div className="flex items-center space-x-4">
                        <div className="flex items-center space-x-1">
                          <DollarSign className="h-4 w-4" />
                          <span data-testid={`text-total-volume-${market.id}`}>
                            {formatCurrency(market.totalVolume)} Vol.
                          </span>
                        </div>
                        <div>
                          <span>Politics</span>
                        </div>
                      </div>
                      <div className="flex items-center space-x-1">
                        <Clock className="h-4 w-4" />
                        <span>in 3 months</span>
                      </div>
                    </div>
                  </CardContent>
                </Card>
              ))}
            </div>
          ) : (
            <Card>
              <CardContent className="p-8 text-center text-muted-foreground">
                <TrendingUp className="h-12 w-12 mx-auto mb-4 opacity-50" />
                <h3 className="text-lg font-semibold mb-2">No Related Prediction Markets</h3>
                <p>There are no prediction markets related to this article yet.</p>
              </CardContent>
            </Card>
          )}
        </section>
      </main>

      {/* Footer */}
      <Footer />
    </div>
  );
}