package dialogue

import (
	"testing"
	"time"
)

var base = time.Date(2026, 7, 31, 12, 0, 0, 0, time.UTC)

func TestPendingQuestionIsExpired(t *testing.T) {
	cases := []struct {
		name string
		ttl  time.Duration
		now  time.Time
		want bool
	}{
		{"fresh", time.Minute, base.Add(10 * time.Second), false},
		{"exactly at ttl", time.Minute, base.Add(time.Minute), false},
		{"past ttl", time.Minute, base.Add(2 * time.Minute), true},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			q := &PendingQuestion{Asked: base, TTL: tc.ttl}
			if got := q.IsExpired(tc.now); got != tc.want {
				t.Fatalf("IsExpired = %v, want %v", got, tc.want)
			}
		})
	}
}

func TestClarifyStoreGetPutDelete(t *testing.T) {
	s := NewClarifyStore(time.Minute)

	if got := s.Get("voice", base); got != nil {
		t.Fatalf("empty store returned %+v", got)
	}

	q := &PendingQuestion{Intent: IntentReminder, Missing: []Slot{SlotTime}, Asked: base}
	s.Put("voice", q)
	if q.TTL != time.Minute {
		t.Fatalf("Put did not apply the default TTL, got %v", q.TTL)
	}
	if got := s.Get("voice", base.Add(time.Second)); got != q {
		t.Fatalf("Get returned %+v, want the parked question", got)
	}

	// Expired questions are dropped on read, not returned.
	if got := s.Get("voice", base.Add(2*time.Minute)); got != nil {
		t.Fatalf("expired Get returned %+v", got)
	}
	if got := s.Get("voice", base); got != nil {
		t.Fatalf("expired question was not deleted: %+v", got)
	}

	s.Put("voice", &PendingQuestion{Asked: base, TTL: time.Hour})
	s.Delete("voice")
	if got := s.Get("voice", base); got != nil {
		t.Fatalf("Delete left %+v", got)
	}
}

func TestNewClarifyStoreDefaultTTL(t *testing.T) {
	s := NewClarifyStore(0)
	q := &PendingQuestion{Asked: base}
	s.Put("voice", q)
	if q.TTL != 90*time.Second {
		t.Fatalf("TTL = %v, want 90s", q.TTL)
	}
}

func TestAnswerFillsOnlyMissingSlots(t *testing.T) {
	answerTime := base.Add(3 * time.Hour)
	other := base.Add(9 * time.Hour)

	cases := []struct {
		name    string
		parked  Slots
		missing []Slot
		text    string
		answer  Slots
		want    Slots
	}{
		{
			name:    "fills the missing time",
			parked:  Slots{Text: "напомни позвонить"},
			missing: []Slot{SlotTime},
			text:    "в три",
			answer:  Slots{Time: answerTime, HasTime: true},
			want:    Slots{Text: "напомни позвонить", Time: answerTime, HasTime: true},
		},
		{
			name:    "does not overwrite a filled time",
			parked:  Slots{Time: other, HasTime: true},
			missing: []Slot{SlotTime},
			text:    "в три",
			answer:  Slots{Time: answerTime, HasTime: true},
			want:    Slots{Time: other, HasTime: true},
		},
		{
			name:    "ignores slots that were not missing",
			parked:  Slots{Key: "water", HasKey: true},
			missing: []Slot{SlotValue},
			text:    "два литра",
			answer:  Slots{Key: "sleep", HasKey: true, Value: "2l"},
			want:    Slots{Key: "water", HasKey: true, Value: "2l"},
		},
		{
			name:    "fills key when empty",
			parked:  Slots{},
			missing: []Slot{SlotKey, SlotValue},
			text:    "воды",
			answer:  Slots{Key: "water", HasKey: true, Value: `"drank"`},
			want:    Slots{Key: "water", HasKey: true, Value: `"drank"`},
		},
		{
			name:    "fills fn and its args",
			parked:  Slots{},
			missing: []Slot{SlotFn},
			text:    "перезапусти nginx",
			answer:  Slots{Fn: "restart", Args: []string{"nginx"}, HasFn: true},
			want:    Slots{Fn: "restart", Args: []string{"nginx"}, HasFn: true},
		},
		{
			name:    "keeps existing args when fn was already known",
			parked:  Slots{Fn: "restart", Args: []string{"nginx"}, HasFn: true},
			missing: []Slot{SlotFn},
			text:    "останови postgres",
			answer:  Slots{Fn: "stop", Args: []string{"postgres"}, HasFn: true},
			want:    Slots{Fn: "restart", Args: []string{"nginx"}, HasFn: true},
		},
		{
			name:    "raw answer becomes the text when nothing was parsed",
			parked:  Slots{},
			missing: []Slot{SlotText},
			text:    "купить хлеб",
			answer:  Slots{},
			want:    Slots{Text: "купить хлеб"},
		},
		{
			name:    "parsed text wins over the raw answer",
			parked:  Slots{},
			missing: []Slot{SlotText},
			text:    "запиши купить хлеб",
			answer:  Slots{Text: "купить хлеб"},
			want:    Slots{Text: "купить хлеб"},
		},
		{
			name:    "empty answer leaves the slot missing",
			parked:  Slots{Text: "напомни"},
			missing: []Slot{SlotTime},
			text:    "не знаю",
			answer:  Slots{},
			want:    Slots{Text: "напомни"},
		},
	}

	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			q := &PendingQuestion{Slots: tc.parked, Missing: tc.missing, Asked: base}
			got := q.Answer(tc.text, tc.answer)
			if got.Time != tc.want.Time || got.HasTime != tc.want.HasTime ||
				got.Key != tc.want.Key || got.HasKey != tc.want.HasKey ||
				got.Value != tc.want.Value || got.Text != tc.want.Text ||
				got.Fn != tc.want.Fn || got.HasFn != tc.want.HasFn {
				t.Fatalf("Answer = %+v, want %+v", got, tc.want)
			}
			if len(got.Args) != len(tc.want.Args) {
				t.Fatalf("Args = %v, want %v", got.Args, tc.want.Args)
			}
			for i := range got.Args {
				if got.Args[i] != tc.want.Args[i] {
					t.Fatalf("Args = %v, want %v", got.Args, tc.want.Args)
				}
			}
		})
	}
}

func TestCanAskCapsAtOneQuestion(t *testing.T) {
	if MaxAttempts != 1 {
		t.Fatalf("MaxAttempts = %d, want 1 (Maven asks once, she is not a nag)", MaxAttempts)
	}
	q := &PendingQuestion{Asked: base}
	if !q.CanAsk() {
		t.Fatal("a fresh question should be askable")
	}
	q.Attempts = MaxAttempts
	if q.CanAsk() {
		t.Fatal("the question should not be asked twice")
	}
}

func TestStillMissing(t *testing.T) {
	want := []Slot{SlotTime, SlotKey, SlotValue, SlotFn, SlotText}
	cases := []struct {
		name  string
		slots Slots
		want  []Slot
	}{
		{"all empty", Slots{}, want},
		{
			name:  "all filled",
			slots: Slots{Time: base, HasTime: true, Key: "water", HasKey: true, Value: "1l", Fn: "restart", HasFn: true, Text: "t"},
			want:  nil,
		},
		{
			name:  "only value left",
			slots: Slots{Time: base, HasTime: true, Key: "water", HasKey: true, Fn: "restart", HasFn: true, Text: "t"},
			want:  []Slot{SlotValue},
		},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			got := StillMissing(want, tc.slots)
			if len(got) != len(tc.want) {
				t.Fatalf("StillMissing = %v, want %v", got, tc.want)
			}
			for i := range got {
				if got[i] != tc.want[i] {
					t.Fatalf("StillMissing = %v, want %v", got, tc.want)
				}
			}
		})
	}
}