package web

// R-922 (operator ruling 2026-10-09 11:19, option A): when the household clears its notification address on
// the dashboard, the hub deletes the stored address. The hub cannot tell that apart from an unconfigured box
// pushing an empty address (its no-clobber guard, audit F12) — so the controller SAYS so: the push carries
// `"email_cleared": true`, and ONLY after a deliberate clear. Asserted on the WIRE (a real Notifier against an
// httptest hub), not on a mock's call count.

import (
	"encoding/json"
	"io"
	"log"
	"net/http"
	"net/http/httptest"
	"net/url"
	"sync"
	"testing"

	"gitea.dooplex.hu/admin/felhom-controller/internal/notify"
	"gitea.dooplex.hu/admin/felhom-controller/internal/settings"
)

type prefsHub struct {
	mu     sync.Mutex
	bodies []map[string]json.RawMessage
}

func (h *prefsHub) last(t *testing.T) map[string]json.RawMessage {
	t.Helper()
	h.mu.Lock()
	defer h.mu.Unlock()
	if len(h.bodies) == 0 {
		t.Fatal("no preferences push reached the hub")
	}
	return h.bodies[len(h.bodies)-1]
}

func (h *prefsHub) count() int {
	h.mu.Lock()
	defer h.mu.Unlock()
	return len(h.bodies)
}

// r922Server is notifyGuardServer with a REAL notifier aimed at a capturing hub.
func r922Server(t *testing.T) (*Server, *settings.Settings, *prefsHub) {
	t.Helper()
	s, sett := notifyGuardServer(t)
	hub := &prefsHub{}
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/api/v1/preferences" {
			w.WriteHeader(http.StatusOK)
			return
		}
		raw, _ := io.ReadAll(r.Body)
		var m map[string]json.RawMessage
		if err := json.Unmarshal(raw, &m); err != nil {
			t.Errorf("preferences push is not a JSON object: %v", err)
		}
		hub.mu.Lock()
		hub.bodies = append(hub.bodies, m)
		hub.mu.Unlock()
		w.WriteHeader(http.StatusOK)
	}))
	t.Cleanup(srv.Close)
	s.notifier = notify.New(srv.URL, "test-key", "c1", sett, log.New(io.Discard, "", 0), false)
	if !s.notifier.IsEnabled() {
		t.Fatal("test notifier not enabled")
	}
	return s, sett, hub
}

func clearForm() url.Values {
	return url.Values{"notification_email": {""}, "cooldown_hours": {"6"}} // no event_* boxes
}

func flagOf(t *testing.T, body map[string]json.RawMessage) (present bool, value bool) {
	t.Helper()
	raw, ok := body["email_cleared"]
	if !ok {
		return false, false
	}
	var v bool
	if err := json.Unmarshal(raw, &v); err != nil {
		t.Fatalf("email_cleared is not a boolean: %s", raw)
	}
	return true, v
}

func emailOf(t *testing.T, body map[string]json.RawMessage) string {
	t.Helper()
	var e string
	_ = json.Unmarshal(body["email"], &e)
	return e
}

// RED TEST. A household that had an address and clears it: the push carries email_cleared:true with an empty
// address. Today's push carries no flag, so the hub keeps the old address (seen on Tester 1, 2026-10-09).
// The flag also rides the NEXT push (the debug resync reads the stored prefs) and a second empty save —
// it stays while the address stays empty, so a push the hub missed is repaired by the next one.
func TestR922_DeliberateClearSendsEmailCleared(t *testing.T) {
	s, sett, hub := r922Server(t)
	if err := sett.SetNotificationPrefs(&settings.NotificationPrefs{
		Email: "household@example.hu", EnabledEvents: []string{"backup_failed"}, CooldownHours: 6,
	}); err != nil {
		t.Fatal(err)
	}

	postNotifications(t, s, clearForm())
	body := hub.last(t)
	if present, v := flagOf(t, body); !present || !v {
		t.Fatalf("R-922: the push after a deliberate clear carries no email_cleared:true (present=%v value=%v) — the hub keeps the old address; body keys=%v", present, v, keysOf(body))
	}
	if e := emailOf(t, body); e != "" {
		t.Fatalf("email = %q, want empty beside the clear flag", e)
	}

	// The next push from the STORED prefs (the debug resync) carries it too.
	before := hub.count()
	s.debugPreferencesSync(httptest.NewRecorder(), httptest.NewRequest(http.MethodPost, "/api/debug/preferences/sync", nil))
	if hub.count() != before+1 {
		t.Fatalf("the resync did not push")
	}
	if present, v := flagOf(t, hub.last(t)); !present || !v {
		t.Fatalf("the stored clear marker did not ride the next push (present=%v value=%v)", present, v)
	}

	// A second empty save keeps it (the stored address is already empty; the household's clear still stands).
	postNotifications(t, s, clearForm())
	if present, v := flagOf(t, hub.last(t)); !present || !v {
		t.Fatalf("a second empty save dropped the clear flag (present=%v value=%v)", present, v)
	}
}

// A box that never had an address must NOT send the flag: its empty push is exactly the case the hub's
// no-clobber guard protects (a provisioning-seeded address must survive an unconfigured box).
func TestR922_NeverConfiguredBoxSendsNoFlag(t *testing.T) {
	s, _, hub := r922Server(t)

	postNotifications(t, s, clearForm())
	if present, _ := flagOf(t, hub.last(t)); present {
		t.Fatalf("a never-configured box sent email_cleared — the hub would delete a seeded address; body keys=%v", keysOf(hub.last(t)))
	}
	s.debugPreferencesSync(httptest.NewRecorder(), httptest.NewRequest(http.MethodPost, "/api/debug/preferences/sync", nil))
	if present, _ := flagOf(t, hub.last(t)); present {
		t.Fatalf("the resync of a never-configured box sent email_cleared")
	}
}

// Setting a new address after a clear drops the flag: the push carries the new address and no flag, and the
// later pushes stay clean.
func TestR922_NewAddressDropsFlag(t *testing.T) {
	s, sett, hub := r922Server(t)
	if err := sett.SetNotificationPrefs(&settings.NotificationPrefs{
		Email: "old@example.hu", EnabledEvents: []string{"backup_failed"}, CooldownHours: 6,
	}); err != nil {
		t.Fatal(err)
	}
	postNotifications(t, s, clearForm())
	if present, v := flagOf(t, hub.last(t)); !present || !v {
		t.Fatalf("precondition: the clear did not send the flag (present=%v value=%v)", present, v)
	}

	postNotifications(t, s, url.Values{
		"notification_email":  {"new@example.hu"},
		"event_backup_failed": {"on"},
		"cooldown_hours":      {"6"},
	})
	body := hub.last(t)
	if present, _ := flagOf(t, body); present {
		t.Fatalf("the push with a new address still carries email_cleared; body keys=%v", keysOf(body))
	}
	if e := emailOf(t, body); e != "new@example.hu" {
		t.Fatalf("email = %q, want new@example.hu", e)
	}
	s.debugPreferencesSync(httptest.NewRecorder(), httptest.NewRequest(http.MethodPost, "/api/debug/preferences/sync", nil))
	if present, _ := flagOf(t, hub.last(t)); present {
		t.Fatalf("the stored marker survived a new address — the next push still carries email_cleared")
	}
}

func keysOf(m map[string]json.RawMessage) []string {
	out := make([]string, 0, len(m))
	for k := range m {
		out = append(out, k)
	}
	return out
}