import type { NextApiRequest, NextApiResponse } from "next"
import { db, schema } from '../../../lib/db/connection'
import { count, gte, eq } from 'drizzle-orm'

export default async function handler(req: NextApiRequest, res: NextApiResponse) {
  if (req.method !== "GET") return res.status(405).json({ error: "Method not allowed" })
  
  try {
    // Get performance metrics
    const weekAgo = new Date(Date.now() - 7 * 24 * 60 * 60 * 1000)
    
    const [
      totalSources,
      verifiedSources,
      highRiskSources,
      sourcesLastWeek
    ] = await Promise.all([
      db.select({ count: count() }).from(schema.sources),
      db.select({ count: count() }).from(schema.sources).where(eq(schema.sources.status, 'verified')),
      db.select({ count: count() }).from(schema.sources).where(gte(schema.sources.riskLevel, 4)),
      db.select({ count: count() }).from(schema.sources).where(gte(schema.sources.createdAt, weekAgo))
    ])
    
    // Get API usage simulation
    const apiUsage = {
      daily_requests: Math.floor(Math.random() * 10000) + 5000,
      avg_response_time: Math.floor(Math.random() * 150) + 50,
      error_rate: Math.random() * 0.05
    }
    
    res.json({
      database_stats: {
        total_sources: totalSources[0].count,
        verified_sources: verifiedSources[0].count,
        high_risk_sources: highRiskSources[0].count,
        sources_last_week: sourcesLastWeek[0].count
      },
      api_performance: apiUsage,
      last_updated: new Date().toISOString()
    })
    
  } catch (error) {
    console.error('Analytics error:', error)
    res.status(500).json({ error: "Failed to fetch analytics" })
  }
}