package settings

import (
	"path/filepath"
	"testing"
)

func contains(list []string, want string) bool {
	for _, e := range list {
		if e == want {
			return true
		}
	}
	return false
}
func count(list []string, want string) int {
	n := 0
	for _, e := range list {
		if e == want {
			n++
		}
	}
	return n
}

// F2a: the new warning type is on by default for new customers.
func TestDefaultEnabledEvents_ContainsEnlargeBlocked(t *testing.T) {
	if !contains(DefaultEnabledEvents, "offbox_enlarge_blocked") {
		t.Error("DefaultEnabledEvents must contain offbox_enlarge_blocked (new customers get it)")
	}
}

// F2b: an EXISTING customer's stored prefs (predating the type) gain it via append-if-absent —
// idempotent (two reads → one entry) and their OTHER choices are preserved.
func TestGetNotificationPrefs_MigratesExisting(t *testing.T) {
	s, err := Load(filepath.Join(t.TempDir(), "settings.json"), discardLog())
	if err != nil {
		t.Fatal(err)
	}
	// A customer who kept only two events and never had the new one.
	if err := s.SetNotificationPrefs(&NotificationPrefs{
		Email:         "c@example.com",
		EnabledEvents: []string{"backup_failed", "disk_warning"},
		CooldownHours: 6,
	}); err != nil {
		t.Fatal(err)
	}

	p1 := s.GetNotificationPrefs()
	if !contains(p1.EnabledEvents, "offbox_enlarge_blocked") {
		t.Error("existing prefs must gain offbox_enlarge_blocked (append-if-absent migration)")
	}
	if !contains(p1.EnabledEvents, "backup_failed") || !contains(p1.EnabledEvents, "disk_warning") {
		t.Error("the customer's existing choices must be preserved")
	}

	// idempotent: a second read still has exactly ONE entry.
	p2 := s.GetNotificationPrefs()
	if c := count(p2.EnabledEvents, "offbox_enlarge_blocked"); c != 1 {
		t.Errorf("migration must be idempotent, got %d entries", c)
	}
}

// A customer who already has the type keeps exactly one (no duplication).
func TestGetNotificationPrefs_AlreadyPresentNoDuplicate(t *testing.T) {
	s, err := Load(filepath.Join(t.TempDir(), "settings.json"), discardLog())
	if err != nil {
		t.Fatal(err)
	}
	if err := s.SetNotificationPrefs(&NotificationPrefs{
		EnabledEvents: []string{"offbox_enlarge_blocked", "backup_failed"},
		CooldownHours: 6,
	}); err != nil {
		t.Fatal(err)
	}
	if c := count(s.GetNotificationPrefs().EnabledEvents, "offbox_enlarge_blocked"); c != 1 {
		t.Errorf("already-present type must not duplicate, got %d", c)
	}
}