package watcher_test

import (
	"maps"
	"slices"
	"testing"

	"sneak.berlin/go/dnswatcher/internal/state"
	"sneak.berlin/go/dnswatcher/internal/watcher"
)

// TestRemovedTargetsLeaveTheState loads a state saved while a domain
// and a hostname now removed from the configuration were still in it,
// and runs the removal that Run does before the first check. The
// removed names' domain, hostname and certificate entries are gone,
// the configured names' are kept, and nothing is notified. Nothing is
// looked up: the watcher has no resolver.
func TestRemovedTargetsLeaveTheState(t *testing.T) {
	t.Parallel()

	const (
		removedDomain = "example.com"
		removedHost   = "www.example.com"
	)

	cfg := defaultTestConfig(t)
	cfg.Domains = []string{domain}
	cfg.Hostnames = []string{host}

	deps := newTestDeps(t, cfg)
	w := watcher.NewForTest(
		cfg, deps.state, nil,
		deps.portChecker, deps.tlsChecker, deps.notifier,
	)

	// The state a check of all four names saves, each name at ip1.
	for _, name := range []string{domain, removedDomain} {
		deps.state.SetDomainState(name, &state.DomainState{
			Nameservers: []string{nsA},
		})
	}

	for _, name := range []string{domain, host, removedDomain, removedHost} {
		deps.state.SetHostnameState(name, saved(
			map[string]*state.NameserverRecordState{
				nsA: answered(map[string][]string{"A": {ip1}}),
			},
		))
		deps.state.SetCertificateState(
			ip1+":443:"+name, &state.CertificateState{Status: "ok"},
		)
	}

	err := deps.state.Save()
	if err != nil {
		t.Fatalf("saving the state: %v", err)
	}

	err = deps.state.Load()
	if err != nil {
		t.Fatalf("loading the state: %v", err)
	}

	w.CleanupRemovedTargets()

	snap := deps.state.GetSnapshot()

	got := slices.Sorted(maps.Keys(snap.Domains))
	if want := []string{domain}; !slices.Equal(got, want) {
		t.Errorf("domain entries %v, want %v", got, want)
	}

	got = slices.Sorted(maps.Keys(snap.Hostnames))
	if want := []string{domain, host}; !slices.Equal(got, want) {
		t.Errorf("hostname entries %v, want %v", got, want)
	}

	got = slices.Sorted(maps.Keys(snap.Certificates))
	if want := []string{
		ip1 + ":443:" + domain, ip1 + ":443:" + host,
	}; !slices.Equal(got, want) {
		t.Errorf("certificate entries %v, want %v", got, want)
	}

	if sent := deps.notifier.getNotifications(); len(sent) != 0 {
		t.Errorf("sent %v, want nothing", sent)
	}
}

// TestCertificateStateForAnAddressGone runs the port checks on hostname
// state built here for a configured hostname, with certificate entries
// saved for it at ip1, ip2 and an IPv6 address. When its nameservers
// answered with ip1 and the IPv6 address, the entry for ip2 is removed.
// When none of them answered, its addresses are not known, and every
// entry is kept. Nothing is notified, and nothing is looked up.
func TestCertificateStateForAnAddressGone(t *testing.T) {
	t.Parallel()

	const ip6 = "2001:db8::1"

	tests := []struct {
		name     string
		hostname *state.HostnameState
		want     []string
	}{
		{
			"answered without ip2",
			saved(map[string]*state.NameserverRecordState{
				nsA: answered(map[string][]string{
					"A": {ip1}, "AAAA": {ip6},
				}),
			}),
			[]string{ip1 + ":443:" + host, ip6 + ":443:" + host},
		},
		{
			"no nameserver answered",
			saved(map[string]*state.NameserverRecordState{
				nsA: failed(), nsB: failed(),
			}),
			[]string{
				ip1 + ":443:" + host,
				ip2 + ":443:" + host,
				ip6 + ":443:" + host,
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			t.Parallel()

			cfg := defaultTestConfig(t)
			cfg.Hostnames = []string{host}

			deps := newTestDeps(t, cfg)
			w := watcher.NewForTest(
				cfg, deps.state, nil,
				deps.portChecker, deps.tlsChecker, deps.notifier,
			)
			w.SetFirstRun(false)

			deps.state.SetHostnameState(host, tt.hostname)

			for _, ip := range []string{ip1, ip2, ip6} {
				deps.state.SetCertificateState(
					ip+":443:"+host, &state.CertificateState{Status: "ok"},
				)
			}

			w.CheckAllPorts(t.Context())

			got := slices.Sorted(maps.Keys(deps.state.GetSnapshot().Certificates))
			if !slices.Equal(got, tt.want) {
				t.Errorf("certificate entries %v, want %v", got, tt.want)
			}

			if sent := deps.notifier.getNotifications(); len(sent) != 0 {
				t.Errorf("sent %v, want nothing", sent)
			}
		})
	}
}