package querylog

import (
	"net"
	"testing"
	"time"

	"github.com/AdguardTeam/golibs/timeutil"
	"github.com/miekg/dns"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestQueryLog_Search_findClient(t *testing.T) {
	const knownClientID = "client-1"
	const knownClientName = "Known Client 1"
	const unknownClientID = "client-2"

	knownClient := &Client{
		Name: knownClientName,
	}

	findClientCalls := 0
	findClient := func(ids []string) (c *Client, _ error) {
		defer func() { findClientCalls++ }()

		if len(ids) == 0 {
			return nil, nil
		}

		if ids[0] == knownClientID {
			return knownClient, nil
		}

		return nil, nil
	}

	l, err := newQueryLog(Config{
		FindClient:        findClient,
		BaseDir:           t.TempDir(),
		RotationIvl:       timeutil.Day,
		MemSize:           100,
		Enabled:           true,
		FileEnabled:       true,
		AnonymizeClientIP: false,
	})
	require.NoError(t, err)
	t.Cleanup(l.Close)

	q := &dns.Msg{
		Question: []dns.Question{{
			Name: "example.com",
		}},
	}

	l.Add(&AddParams{
		Question: q,
		ClientID: knownClientID,
		ClientIP: net.IP{1, 2, 3, 4},
	})

	// Add the same thing again to test the cache.
	l.Add(&AddParams{
		Question: q,
		ClientID: knownClientID,
		ClientIP: net.IP{1, 2, 3, 4},
	})

	l.Add(&AddParams{
		Question: q,
		ClientID: unknownClientID,
		ClientIP: net.IP{1, 2, 3, 5},
	})

	sp := &searchParams{
		// Add some time to the "current" one to protect against
		// low-resolution timers on some Windows machines.
		//
		// TODO(a.garipov): Use some kind of timeSource interface
		// instead of relying on time.Now() in tests.
		olderThan: time.Now().Add(10 * time.Second),
		limit:     3,
	}
	entries, _ := l.search(sp)
	assert.Equal(t, 2, findClientCalls)

	require.Len(t, entries, 3)

	assert.Nil(t, entries[0].client)

	gotClient := entries[2].client
	require.NotNil(t, gotClient)

	assert.Equal(t, knownClientName, gotClient.Name)
}

// BenchmarkQueryLog_Search compares the speed of search with limit-offset
// parameters and the one with oldenThan timestamp specified.
func BenchmarkQueryLog_Search(b *testing.B) {
	l, err := newQueryLog(Config{
		Enabled:     true,
		RotationIvl: timeutil.Day,
		MemSize:     100,
		BaseDir:     b.TempDir(),
	})
	require.NoError(b, err)

	const (
		entNum           = 100000
		firstPageDomain  = "first.example.org"
		secondPageDomain = "second.example.org"
	)
	// Add entries to the log.
	for i := 0; i < entNum; i++ {
		addEntry(l, secondPageDomain, net.IPv4(1, 1, 1, 1), net.IPv4(2, 2, 2, 1))
	}
	// Write them to the first file.
	require.NoError(b, l.flushLogBuffer())

	// Add more to the in-memory part of log.
	for i := 0; i < entNum; i++ {
		addEntry(l, firstPageDomain, net.IPv4(1, 1, 1, 1), net.IPv4(2, 2, 2, 1))
	}

	b.Run("limit_offset", func(b *testing.B) {
		params := newSearchParams()

		b.ReportAllocs()

		for i := 0; i < b.N; i++ {
			params.offset += params.limit
			_, _ = l.search(params)
		}
	})

	b.Run("timestamp", func(b *testing.B) {
		params := newSearchParams()
		params.olderThan = time.Now().Add(-1 * time.Hour)

		b.ReportAllocs()

		for i := 0; i < b.N; i++ {
			params.olderThan = params.olderThan.Add(1 * time.Minute)
			_, _ = l.search(params)
		}
	})

	// Most recent result, on a MBP15:
	//
	// goos: darwin
	// goarch: amd64
	// pkg: github.com/AdguardTeam/AdGuardHome/internal/querylog
	// cpu: Intel(R) Core(TM) i7-8750H CPU @ 2.20GHz
	// BenchmarkQueryLog_Search
	// BenchmarkQueryLog_Search/limit_offset
	// BenchmarkQueryLog_Search/limit_offset-12         	     547	   2066079 ns/op	 2325019 B/op	   26633 allocs/op
	// BenchmarkQueryLog_Search/timestamp
	// BenchmarkQueryLog_Search/timestamp-12            	    1303	   2028888 ns/op	 2219337 B/op	   25194 allocs/op
}