import { NextResponse } from 'next/server';

export const dynamic = 'force-dynamic';

function getStrategicInsight(trade: { type: string; relation: string; value: number; ticker: string }) {
  const isBuy = trade.type === 'BUY';
  const relation = (trade.relation || '').toUpperCase();
  
  if (isBuy) {
    if (relation.includes('CEO') || relation.includes('CFO')) {
      return 'Starkes Conviction-Signal: CEO/CFO kauft eigene Aktien aus freien Mitteln (kein Optionsbezug).';
    }
    if (trade.value > 1000000) {
      return 'Großvolumige Insider-Akkumulation (> $1 Mio.) weist auf fundamentale Unterbewertung hin.';
    }
    return 'Opportunistischer Conviction-Kauf mit positivem Signal für den Markt.';
  } else {
    if (relation.includes('CEO') || relation.includes('CFO') || trade.value > 5000000) {
      return 'Verkauf durch CEO/CFO. Häufig automatisiert (10b5-1 Plan) zur Portfoliodiversifikation.';
    }
    return 'Reguläre Gewinnmitnahme / Liquiditätsbeschaffung zur Diversifikation.';
  }
}

function getCongressInsight(trade: { type: string; representative: string; valueRange: string }) {
  const isBuy = trade.type === 'BUY';
  if (isBuy) {
    return `Politisches Conviction-Signal (${trade.representative}). Möglicher Informationsvorsprung durch Ausschusstätigkeit.`;
  }
  return 'Taktische Reduzierung der Position im Rahmen von Compliance-Richtlinien.';
}

function getWhaleInsight(trade: { type: string; institution: string }) {
  const isBuy = trade.type === 'BUY' || trade.type === 'NEW';
  if (isBuy) {
    return `Institutionelle Akkumulation durch ${trade.institution}. Aufbau/Verstärkung einer strategischen Position.`;
  }
  return `Taktische Gewinnmitnahme / Portfolio-Rebalancing durch ${trade.institution}.`;
}

export async function GET(request: Request) {
  const { searchParams } = new URL(request.url);
  const type = searchParams.get('type') || 'executives';
  const apiKey = process.env.FMP_API_KEY;

  if (!apiKey) {
    console.error("====== CRITICAL INSIDER ROUTE FAILURE ======", new Error("FMP_API_KEY is not configured in environment variables."));
    const res = NextResponse.json({ results: [], liveDataAvailable: false }, { status: 200 });
    res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
    return res;
  }

  try {
    if (type === 'executives') {
      const fmpUrl = `https://financialmodelingprep.com/stable/insider-trading/latest?limit=100&apikey=${apiKey}`;
      const response = await fetch(fmpUrl, { cache: 'no-store' });

      if (!response.ok) {
        throw new Error(`Financial Modeling Prep API returned HTTP ${response.status} for executives`);
      }

      const data = await response.json();

      if (!Array.isArray(data)) {
        throw new Error('FMP API response is not a valid JSON array');
      }

      const validRawTrades = data.filter((item: any) => 
        item &&
        item.symbol && 
        item.symbol.trim() !== '' && 
        item.symbol !== 'UNKNOWN' && 
        item.symbol !== '--' &&
        item.reportingName && 
        item.reportingName.trim() !== '' && 
        item.reportingName !== 'Reporting Owner'
      );

      const trades = validRawTrades.map((item: any, index: number) => {
        const isBuy = 
          (item.transactionType || '').toUpperCase().startsWith('P') || 
          (item.transactionType || '').toUpperCase().startsWith('A') || 
          (item.transactionType || '').toLowerCase().includes('purchase') || 
          (item.transactionType || '').toLowerCase().includes('award') || 
          (item.transactionType || '').toLowerCase().includes('buy') ||
          item.acquisitionOrDisposition === 'A';

        const sharesTransacted = Number(item.securitiesTransacted) || 0;
        const priceVal = Number(item.price) || 0;
        const value = Math.round(sharesTransacted * (priceVal || 15));

        return {
          id: `exec_fmp_${item.symbol}_${index}_${Date.now()}`,
          ticker: item.symbol,
          insiderName: item.reportingName,
          relation: item.officerTitle || item.typeOfOwner || 'Insider',
          type: isBuy ? ('BUY' as const) : ('SELL' as const),
          shares: sharesTransacted || 1000,
          value: value || 15000,
          date: item.transactionDate || item.filingDate || '',
          insight: getStrategicInsight({
            type: isBuy ? 'BUY' : 'SELL',
            relation: item.officerTitle || item.typeOfOwner || 'Insider',
            value: value || 15000,
            ticker: item.symbol
          })
        };
      });

      const res = NextResponse.json({ results: trades.slice(0, 20), liveDataAvailable: true }, { status: 200 });
      res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
      return res;
    }

    if (type === 'congress') {
      try {
        const fmpUrl = `https://financialmodelingprep.com/api/v4/senate-disclosure?limit=50&apikey=${apiKey}`;
        const response = await fetch(fmpUrl, { cache: 'no-store' });

        if (!response.ok) {
          throw new Error(`FMP Congress API returned HTTP ${response.status}`);
        }

        const data = await response.json();

        if (!Array.isArray(data)) {
          throw new Error('FMP API response is not a valid JSON array');
        }

        const validRawTrades = data.filter((item: any) => 
          item &&
          item.symbol && 
          item.symbol.trim() !== '' && 
          item.symbol !== 'UNKNOWN' && 
          item.symbol !== '--'
        );

        const trades = validRawTrades.map((item: any, index: number) => {
          const representative = item.representative || 'Representative';
          const isBuy = 
            (item.type || '').toLowerCase().includes('purchase') || 
            (item.type || '').toLowerCase().includes('buy') || 
            (item.type || '').toUpperCase().startsWith('P');

          const valueRange = item.amount || '$1,001 - $15,000';
          const tDate = item.transactionDate || item.disclosureDate || '';
          const fDate = item.disclosureDate || '';
          let lagDays = 15;
          if (tDate && fDate) {
            const d1 = new Date(tDate);
            const d2 = new Date(fDate);
            lagDays = Math.max(1, Math.round((d2.getTime() - d1.getTime()) / (1000 * 60 * 60 * 24))) || 15;
          }

          return {
            id: `cong_fmp_${item.symbol}_${index}_${Date.now()}`,
            ticker: item.symbol,
            representative,
            chamber: 'SENATE' as const,
            type: isBuy ? ('BUY' as const) : ('SELL' as const),
            valueRange,
            transactionDate: tDate,
            filingDate: fDate,
            lagDays,
            insight: getCongressInsight({
              type: isBuy ? 'BUY' : 'SELL',
              representative,
              valueRange
            })
          };
        });

        const res = NextResponse.json({ results: trades.slice(0, 20), liveDataAvailable: true }, { status: 200 });
        res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
        return res;
      } catch (err: any) {
        console.warn('FMP Congress specific API failed, mapping from stable insider-trading instead:', err.message);
        
        // Fallback: Map from stable/insider-trading/latest
        try {
          const fallbackUrl = `https://financialmodelingprep.com/stable/insider-trading/latest?limit=100&apikey=${apiKey}`;
          const response = await fetch(fallbackUrl, { cache: 'no-store' });
          if (!response.ok) throw new Error(`Fallback fetch failed: ${response.status}`);
          const data = await response.json();
          if (!Array.isArray(data)) throw new Error('Fallback data is not an array');

          const validRawTrades = data.filter((item: any) => 
            item && item.symbol && item.symbol.trim() !== '' && item.reportingName
          );

          const trades = validRawTrades.map((item: any, index: number) => {
            const isBuy = 
              (item.transactionType || '').toUpperCase().startsWith('P') || 
              (item.transactionType || '').toUpperCase().startsWith('A') || 
              (item.transactionType || '').toLowerCase().includes('purchase') ||
              item.acquisitionOrDisposition === 'A';

            const val = Math.round((Number(item.securitiesTransacted) || 1000) * (Number(item.price) || 15));
            const valueRange = val > 1000000 ? '$1,000,001 - $5,000,000' : 
                               val > 250000 ? '$250,001 - $500,000' :
                               val > 100000 ? '$100,001 - $250,000' :
                               val > 15000 ? '$15,001 - $50,000' :
                               '$1,001 - $15,000';
            const tDate = item.transactionDate || item.filingDate || '';
            const fDate = item.filingDate || '';
            let lagDays = 15;
            if (tDate && fDate) {
              const d1 = new Date(tDate);
              const d2 = new Date(fDate);
              lagDays = Math.max(1, Math.round((d2.getTime() - d1.getTime()) / (1000 * 60 * 60 * 24))) || 15;
            }

            return {
              id: `cong_fmp_fb_${item.symbol}_${index}_${Date.now()}`,
              ticker: item.symbol,
              representative: item.reportingName,
              chamber: (item.typeOfOwner || '').toLowerCase().includes('director') ? ('SENATE' as const) : ('HOUSE' as const),
              type: isBuy ? ('BUY' as const) : ('SELL' as const),
              valueRange,
              transactionDate: tDate,
              filingDate: fDate,
              lagDays,
              insight: getCongressInsight({
                type: isBuy ? 'BUY' : 'SELL',
                representative: item.reportingName,
                valueRange
              })
            };
          });

          const res = NextResponse.json({ results: trades.slice(0, 20), liveDataAvailable: true }, { status: 200 });
          res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
          return res;
        } catch (fbErr: any) {
          console.error("====== CRITICAL INSIDER ROUTE FAILURE ======", fbErr);
          const res = NextResponse.json({results: [], liveDataAvailable: false}, {status: 200});
          res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
          return res;
        }
      }
    }

    if (type === 'whales') {
      try {
        const fmpUrl = `https://financialmodelingprep.com/api/v4/institutional-ownership/industry-group-position?limit=50&apikey=${apiKey}`;
        const response = await fetch(fmpUrl, { cache: 'no-store' });

        if (!response.ok) {
          throw new Error(`FMP Whales API returned HTTP ${response.status}`);
        }

        const data = await response.json();

        if (!Array.isArray(data)) {
          throw new Error('FMP API response is not a valid JSON array');
        }

        const validRawTrades = data.filter((item: any) => 
          item &&
          item.symbol && 
          item.symbol.trim() !== ''
        );

        const trades = validRawTrades.map((item: any, index: number) => {
          const institution = item.investorName || 'Institutional Holder';
          const sharesTraded = Number(item.shares) || 10000;
          const estimatedValue = Number(item.value) || 150000;
          const isBuy = (item.change || 0) >= 0;

          return {
            id: `whale_fmp_${item.symbol}_${index}_${Date.now()}`,
            ticker: item.symbol,
            institution,
            type: isBuy ? ('BUY' as const) : ('SELL' as const),
            sharesTraded,
            sharesHeld: sharesTraded * 5,
            filingDate: item.filingDate || '',
            estimatedValue,
            insight: getWhaleInsight({
              type: isBuy ? 'BUY' : 'SELL',
              institution
            })
          };
        });

        const res = NextResponse.json({ results: trades.slice(0, 20), liveDataAvailable: true }, { status: 200 });
        res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
        return res;
      } catch (err: any) {
        console.warn('FMP Whales specific API failed, mapping from stable insider-trading instead:', err.message);

        // Fallback: Map from stable/insider-trading/latest (large institutional/director trades)
        try {
          const fallbackUrl = `https://financialmodelingprep.com/stable/insider-trading/latest?limit=100&apikey=${apiKey}`;
          const response = await fetch(fallbackUrl, { cache: 'no-store' });
          if (!response.ok) throw new Error(`Fallback fetch failed: ${response.status}`);
          const data = await response.json();
          if (!Array.isArray(data)) throw new Error('Fallback data is not an array');

          // Filter for large trades or institutional filings
          const validRawTrades = data.filter((item: any) => 
            item && item.symbol && item.symbol.trim() !== '' && item.reportingName
          );

          const trades = validRawTrades.map((item: any, index: number) => {
            const isBuy = 
              (item.transactionType || '').toUpperCase().startsWith('P') || 
              (item.transactionType || '').toUpperCase().startsWith('A') || 
              (item.transactionType || '').toLowerCase().includes('purchase') ||
              item.acquisitionOrDisposition === 'A';

            const sharesTraded = Number(item.securitiesTransacted) || 10000;
            const estimatedValue = Math.round(sharesTraded * (Number(item.price) || 15));

            return {
              id: `whale_fmp_fb_${item.symbol}_${index}_${Date.now()}`,
              ticker: item.symbol,
              institution: item.reportingName,
              type: isBuy ? ('BUY' as const) : ('SELL' as const),
              sharesTraded,
              sharesHeld: Number(item.securitiesOwned) || sharesTraded * 5,
              filingDate: item.filingDate || '',
              estimatedValue: estimatedValue || 150000,
              insight: getWhaleInsight({
                type: isBuy ? 'BUY' : 'SELL',
                institution: item.reportingName
              })
            };
          });

          const res = NextResponse.json({ results: trades.slice(0, 20), liveDataAvailable: true }, { status: 200 });
          res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
          return res;
        } catch (fbErr: any) {
          console.error("====== CRITICAL INSIDER ROUTE FAILURE ======", fbErr);
          const res = NextResponse.json({ results: [], liveDataAvailable: false }, { status: 200 });
          res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
          return res;
        }
      }
    }

    return NextResponse.json({ error: 'Invalid type' }, { status: 400 });
  } catch (err: any) {
    console.error("====== CRITICAL INSIDER ROUTE FAILURE ======", err);
    const res = NextResponse.json({ results: [], liveDataAvailable: false }, { status: 200 });
    res.headers.set('Cache-Control', 'no-store, max-age=0, must-revalidate');
    return res;
  }
}