/**
 * API Route: Get lineage anomalies detected by PlantLineageAgent
 * GET /api/agents/lineage/anomalies
 */

import type { NextApiRequest, NextApiResponse } from 'next';
import { getPlantLineageAgent } from '../../../../lib/agents';

export default async function handler(
  req: NextApiRequest,
  res: NextApiResponse
) {
  if (req.method !== 'GET') {
    return res.status(405).json({ success: false, error: 'Method not allowed' });
  }

  try {
    const { severity, type, limit } = req.query;
    const agent = getPlantLineageAgent();

    let anomalies = agent.getAnomalies();

    // Filter by severity if specified
    if (severity && typeof severity === 'string') {
      const validSeverities = ['low', 'medium', 'high'];
      if (!validSeverities.includes(severity)) {
        return res.status(400).json({
          success: false,
          error: `Invalid severity. Must be one of: ${validSeverities.join(', ')}`
        });
      }
      anomalies = anomalies.filter(a => a.severity === severity);
    }

    // Filter by type if specified
    if (type && typeof type === 'string') {
      const validTypes = ['orphan', 'circular', 'invalid_generation', 'missing_parent', 'suspicious_location'];
      if (!validTypes.includes(type)) {
        return res.status(400).json({
          success: false,
          error: `Invalid type. Must be one of: ${validTypes.join(', ')}`
        });
      }
      anomalies = anomalies.filter(a => a.type === type);
    }

    // Apply limit if specified
    const maxResults = limit ? Math.min(parseInt(limit as string, 10), 100) : 50;
    anomalies = anomalies.slice(0, maxResults);

    // Group by type for summary
    const byType: Record<string, number> = {};
    const bySeverity: Record<string, number> = {};
    const allAnomalies = agent.getAnomalies();

    for (const anomaly of allAnomalies) {
      byType[anomaly.type] = (byType[anomaly.type] || 0) + 1;
      bySeverity[anomaly.severity] = (bySeverity[anomaly.severity] || 0) + 1;
    }

    res.status(200).json({
      success: true,
      summary: {
        total: allAnomalies.length,
        byType,
        bySeverity,
      },
      filters: {
        severity: severity || null,
        type: type || null,
        limit: maxResults,
      },
      anomalies,
    });
  } catch (error: any) {
    console.error('Error getting lineage anomalies:', error);
    res.status(500).json({ success: false, error: error.message || 'Internal server error' });
  }
}