package dialogue

import (
	"testing"
	"time"
)

var clarifyNow = time.Date(2026, 7, 31, 10, 0, 0, 0, time.UTC)

func TestPendingQuestionAnswerFillsOnlyMissing(t *testing.T) {
	fireAt := clarifyNow.Add(time.Hour)
	q := &PendingQuestion{
		Intent:  IntentReminder,
		Slots:   Slots{Key: "mom", HasKey: true, Text: "напомни позвонить маме"},
		Missing: []Slot{SlotTime},
	}
	got := q.Answer("в 11", Slots{Time: fireAt, HasTime: true, Key: "other", HasKey: true})
	if !got.HasTime || !got.Time.Equal(fireAt) {
		t.Fatalf("missing time slot not filled: %+v", got)
	}
	if got.Key != "mom" {
		t.Fatalf("answer overwrote a filled slot: key=%q", got.Key)
	}
	if got.Text != "напомни позвонить маме" {
		t.Fatalf("answer overwrote the original text: %q", got.Text)
	}
}

func TestPendingQuestionAnswerKeepsGapWhenAnswerIsEmpty(t *testing.T) {
	q := &PendingQuestion{Intent: IntentReminder, Missing: []Slot{SlotTime}}
	got := q.Answer("не знаю", Slots{})
	if got.HasTime {
		t.Fatal("empty answer must not fill the slot")
	}
	if len(StillMissing(q.Missing, got)) != 1 {
		t.Fatal("StillMissing should report the unfilled slot")
	}
}

func TestStillMissing(t *testing.T) {
	cases := []struct {
		name  string
		want  []Slot
		slots Slots
		left  int
	}{
		{"all filled", []Slot{SlotTime, SlotKey}, Slots{HasTime: true, HasKey: true}, 0},
		{"time gap", []Slot{SlotTime}, Slots{HasKey: true}, 1},
		{"fn gap", []Slot{SlotFn}, Slots{}, 1},
		{"text filled", []Slot{SlotText}, Slots{Text: "hi"}, 0},
		{"nothing wanted", nil, Slots{}, 0},
	}
	for _, tc := range cases {
		if got := StillMissing(tc.want, tc.slots); len(got) != tc.left {
			t.Errorf("%s: got %v, want %d left", tc.name, got, tc.left)
		}
	}
}

func TestClarifyStoreExpiry(t *testing.T) {
	s := NewClarifyStore(90 * time.Second)
	s.Put("voice", &PendingQuestion{Asked: clarifyNow, Missing: []Slot{SlotTime}})

	if s.Get("voice", clarifyNow.Add(30*time.Second)) == nil {
		t.Fatal("question inside the TTL should be live")
	}
	if s.Get("voice", clarifyNow.Add(2*time.Minute)) != nil {
		t.Fatal("question past the TTL should be dropped")
	}
	if s.Get("voice", clarifyNow) != nil {
		t.Fatal("an expired question must be deleted on read, not linger")
	}
}

func TestClarifyStoreDefaultTTL(t *testing.T) {
	s := NewClarifyStore(0)
	q := &PendingQuestion{Asked: clarifyNow}
	s.Put("voice", q)
	if q.TTL != 90*time.Second {
		t.Fatalf("default TTL not applied: %v", q.TTL)
	}
}

func TestCanAskOnce(t *testing.T) {
	q := &PendingQuestion{}
	if !q.CanAsk() {
		t.Fatal("a fresh question should be askable")
	}
	q.Attempts = MaxAttempts
	if q.CanAsk() {
		t.Fatal("she must not ask twice")
	}
}