package app

import (
	dnscfgpkg "selective-vpn-api/app/dnscfg"
	"time"
)

var dnsBenchmarkDefaultDomains = append([]string(nil), dnscfgpkg.BenchmarkDefaultDomains...)

const (
	dnsBenchmarkProfileQuick = "quick"
	dnsBenchmarkProfileLoad  = "load"
)

type dnsBenchmarkOptions = dnscfgpkg.BenchmarkOptions

func normalizeBenchmarkUpstreams(in []DNSBenchmarkUpstream) []string {
	if len(in) == 0 {
		return nil
	}
	raw := make([]string, 0, len(in))
	for _, item := range in {
		raw = append(raw, item.Addr)
	}
	return dnscfgpkg.NormalizeBenchmarkUpstreamStrings(raw, normalizeDNSUpstream)
}

func benchmarkDNSUpstream(upstream string, domains []string, timeout time.Duration, attempts int, opts dnsBenchmarkOptions) DNSBenchmarkResult {
	classify := func(err error) string {
		switch classifyDNSError(err) {
		case dnsErrorNXDomain:
			return dnscfgpkg.BenchmarkErrorNXDomain
		case dnsErrorTimeout:
			return dnscfgpkg.BenchmarkErrorTimeout
		case dnsErrorTemporary:
			return dnscfgpkg.BenchmarkErrorTemporary
		default:
			return dnscfgpkg.BenchmarkErrorOther
		}
	}
	pkgRes := dnscfgpkg.BenchmarkDNSUpstream(upstream, domains, timeout, attempts, opts, dnsLookupAOnce, classify)
	return DNSBenchmarkResult{
		Upstream:  pkgRes.Upstream,
		Attempts:  pkgRes.Attempts,
		OK:        pkgRes.OK,
		Fail:      pkgRes.Fail,
		NXDomain:  pkgRes.NXDomain,
		Timeout:   pkgRes.Timeout,
		Temporary: pkgRes.Temporary,
		Other:     pkgRes.Other,
		AvgMS:     pkgRes.AvgMS,
		P95MS:     pkgRes.P95MS,
		Score:     pkgRes.Score,
		Color:     pkgRes.Color,
	}
}

func dnsLookupAOnce(host string, upstream string, timeout time.Duration) ([]string, error) {
	return dnscfgpkg.DNSLookupAOnce(host, upstream, timeout, splitDNS, isPrivateIPv4)
}

func benchmarkTopN(results []DNSBenchmarkResult, n int, fallback []string) []string {
	pkgResults := make([]dnscfgpkg.BenchmarkResult, 0, len(results))
	for _, item := range results {
		pkgResults = append(pkgResults, dnscfgpkg.BenchmarkResult{
			Upstream:  item.Upstream,
			Attempts:  item.Attempts,
			OK:        item.OK,
			Fail:      item.Fail,
			NXDomain:  item.NXDomain,
			Timeout:   item.Timeout,
			Temporary: item.Temporary,
			Other:     item.Other,
			AvgMS:     item.AvgMS,
			P95MS:     item.P95MS,
			Score:     item.Score,
			Color:     item.Color,
		})
	}
	return dnscfgpkg.BenchmarkTopN(pkgResults, n, fallback)
}