import { NextResponse } from "next/server"
import { eq } from "drizzle-orm"
import { db } from "@/lib/db"
import { ai_recommendations } from "@/lib/db/schema"
import { getSessionUser } from "@/lib/session"

export async function GET() {
  const user = await getSessionUser()
  if (!user) return NextResponse.json({ error: "Unauthorized" }, { status: 401 })

  const all = await db
    .select()
    .from(ai_recommendations)
    .where(eq(ai_recommendations.user_id, user.id))

  const approved = all.filter((r) => r.status === "approved")
  const dismissed = all.filter((r) => r.status === "dismissed")
  const pending = all.filter((r) => r.status === "pending")

  let totalRevenue = 0
  let totalSavings = 0
  let totalRiskPrevented = 0

  for (const r of approved) {
    const val = Number(r.action_data?.estimated_value ?? 0)
    const vtype = r.action_data?.value_type ?? "revenue"
    if (vtype === "revenue") totalRevenue += val
    else if (vtype === "savings") totalSavings += val
    else if (vtype === "risk_prevention") totalRiskPrevented += val
  }

  const byType = approved.reduce((acc: Record<string, number>, r) => {
    acc[r.type] = (acc[r.type] ?? 0) + 1
    return acc
  }, {})

  return NextResponse.json({
    totals: {
      generated: all.length,
      approved: approved.length,
      dismissed: dismissed.length,
      pending: pending.length,
      approval_rate: all.length > 0 ? Math.round((approved.length / all.length) * 100) : 0,
    },
    impact: {
      revenue: totalRevenue,
      savings: totalSavings,
      risk_prevented: totalRiskPrevented,
      total: totalRevenue + totalSavings + totalRiskPrevented,
    },
    by_type: byType,
    recent_approved: approved
      .sort((a, b) => new Date(b.applied_at ?? 0).getTime() - new Date(a.applied_at ?? 0).getTime())
      .slice(0, 5),
  })
}