package stats

import (
	"context"
	"errors"
	"io"
	"log/slog"
	"os"
	"path/filepath"
	"testing"
	"time"
)

// Figures for chosen views: from the response log, per view, and added
// up for several.
func TestViewFilter(t *testing.T) {
	ctx := context.Background()
	loc := time.FixedZone("test", 0)
	dir := t.TempDir()
	logFile := filepath.Join(dir, "responses.log")
	store, err := OpenStore(filepath.Join(dir, "stats.db"))
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()
	named := newFakeNamed(t)
	clk := &clock{time.Date(2026, 10, 5, 10, 0, 30, 0, loc)}
	opts := Options{QueryLog: true, LogFile: logFile, StatisticsChannel: "unused", TopN: 10,
		RetainMinute: 7 * 24 * time.Hour, RetainHour: 90 * 24 * time.Hour, RetainDay: 730 * 24 * time.Hour, Location: loc}
	zones := func() map[string][]string {
		return map[string][]string{"internal": {"adbraun.lol"}, "external": {"adbraun.lol"}}
	}
	c := NewCollector(store, opts, zones, slog.New(slog.NewTextHandler(io.Discard, nil)))
	c.poller.URL = named.srv.URL
	c.now = clk.now
	c.start(ctx)
	at := time.Date(2026, 10, 5, 10, 0, 40, 0, loc)
	lines := []string{
		logLine(at, "10.10.0.37", "internal", "nas.adbraun.lol", "A", "NOERROR"),
		logLine(at, "10.10.0.37", "internal", "nas.adbraun.lol", "AAAA", "NOERROR"),
		logLine(at, "10.10.0.42", "internal", "nope.adbraun.lol", "A", "NXDOMAIN"),
		logLine(at, "203.0.113.9", "external", "www.adbraun.lol", "A", "NOERROR"),
		logLine(at, "203.0.113.9", "external", "x.example", "A", "REFUSED"),
		logLine(at, "192.0.2.5", "vps", "debian.org", "AAAA", "NOERROR"),
	}
	f, _ := os.Create(logFile)
	for _, l := range lines {
		f.WriteString(l)
	}
	f.Close()
	c.readLog()
	named.add(6, 1)
	clk.t = time.Date(2026, 10, 5, 10, 1, 2, 0, loc)
	c.flush(ctx, false)
	clk.t = time.Date(2026, 10, 5, 11, 0, 2, 0, loc)
	c.flush(ctx, false)

	all := &Querier{Store: store, Opts: opts, Now: clk.now}
	s, err := all.Summary(ctx, 24*time.Hour, 5)
	if err != nil || s.Queries != 6 || s.FilterViews != nil {
		t.Fatalf("all views: %+v %v", s, err)
	}
	in := all.ForViews([]string{"internal"})
	s, err = in.Summary(ctx, 24*time.Hour, 5)
	if err != nil {
		t.Fatal(err)
	}
	if s.Queries != 3 || len(s.Views) != 1 || s.Views[0].Key != "internal" || s.ViewsSince == nil {
		t.Errorf("internal: queries %d views %v since %v", s.Queries, s.Views, s.ViewsSince)
	}
	if len(s.RCodes) != 2 || s.RCodes[0] != (Entry{Key: "NOERROR", Count: 2}) || len(s.QTypes) != 2 {
		t.Errorf("internal rcodes %v qtypes %v", s.RCodes, s.QTypes)
	}
	if s.Tops[KindName][0] != (Entry{Key: "nas.adbraun.lol", Count: 2}) || len(s.Tops[KindNXDomain]) != 1 || len(s.Answers) != 0 {
		t.Errorf("internal tops %v answers %v", s.Tops, s.Answers)
	}
	// Linked views, say: two together.
	two := all.ForViews([]string{"internal", "external"})
	s, _ = two.Summary(ctx, 24*time.Hour, 5)
	if s.Queries != 5 || len(s.Views) != 2 {
		t.Errorf("internal+external: %d %v", s.Queries, s.Views)
	}
	if es, _ := two.Top(ctx, KindClient, 24*time.Hour, 5); len(es) != 3 || es[2].Key != "10.10.0.42" {
		t.Errorf("clients of two views: %v", es)
	}
	if es, _ := two.Breakdown(ctx, "rcode", 24*time.Hour); len(es) != 3 {
		t.Errorf("rcodes of two views: %v", es)
	}
	if _, err := two.Breakdown(ctx, "answer", 24*time.Hour); !errors.Is(err, ErrNotPerView) {
		t.Errorf("answers per view: %v", err)
	}
	tl, err := all.ForViews([]string{"vps"}).Timeline(ctx, 2*time.Hour, "1m", []string{"queries", "rcode:*"})
	if err != nil {
		t.Fatal(err)
	}
	var total int64
	for _, v := range tl.Series[0].Values {
		total += v
	}
	if total != 1 || len(tl.Series) != 2 || tl.Series[1].Key != "rcode:NOERROR" {
		t.Errorf("vps timeline: %d %+v", total, tl.Series)
	}
}