package pipeline

import (
	"fmt"
	"math/rand"
	"net/netip"
	"testing"

	"evobgp/internal/store"
)

// benchPrefixRows generates seed-stable pseudo-random prefixes for aggregation benchmarks.
// v4 blocks are carved from TEST-NET-style ranges; v6 from 2001:db8::/32.
func benchPrefixRows(n int, v6Share float64) []store.PrefixRow {
	r := rand.New(rand.NewSource(42))
	rows := make([]store.PrefixRow, 0, n)
	seen := make(map[string]struct{}, n)
	for len(rows) < n {
		var pfx netip.Prefix
		if r.Float64() < v6Share {
			var a [16]byte
			a[0], a[1] = 0x20, 0x01
			a[2], a[3] = 0x0d, 0xb8
			for i := 4; i < 10; i++ {
				a[i] = byte(r.Intn(256))
			}
			addr := netip.AddrFrom16(a)
			pfx = netip.PrefixFrom(addr, 48+r.Intn(17))
		} else {
			b := []byte{203, 0, 113, 0}
			b[1] = byte(r.Intn(256))
			b[2] = byte(r.Intn(256))
			b[3] = byte(r.Intn(256))
			addr := netip.AddrFrom4([4]byte{b[0], b[1], b[2], b[3]})
			pfx = netip.PrefixFrom(addr, 16+r.Intn(9))
		}
		s := pfx.Masked().String()
		if _, ok := seen[s]; ok {
			continue
		}
		seen[s] = struct{}{}
		rows = append(rows, store.PrefixRow{Prefix: s, Source: "ip_range"})
	}
	return rows
}

func BenchmarkSmartAggregatePrefixRows(b *testing.B) {
	for _, n := range []int{1_000, 10_000, 50_000} {
		rows := benchPrefixRows(n, 0.3)
		b.Run(fmt.Sprintf("n=%d", n), func(b *testing.B) {
			for i := 0; i < b.N; i++ {
				_ = smartAggregatePrefixRows(rows)
			}
		})
	}
}