package domain

import (
	"testing"
	"time"
)

func TestCalculateSubscriptionExpiresAt_duolingoIsLifetime(t *testing.T) {
	start := time.Date(2026, 6, 10, 12, 0, 0, 0, time.UTC)
	got := CalculateSubscriptionExpiresAt(start, "DUOLINGO", 1, "MONTH")
	if !got.Equal(LifetimeSubscriptionExpiresAt) {
		t.Fatalf("expected lifetime expiry, got %v", got)
	}
}

func TestSubscriptionGrantsContentAccess(t *testing.T) {
	if !SubscriptionGrantsContentAccess("LEARN_ENGLISH", "LEARN_ENGLISH") {
		t.Fatal("LEARN_ENGLISH plan should unlock LMS content")
	}
	if SubscriptionGrantsContentAccess("LEARN_ENGLISH", "IELTS") {
		t.Fatal("LEARN_ENGLISH plan should not unlock exam prep content")
	}
	if !SubscriptionGrantsContentAccess("IELTS", "IELTS") {
		t.Fatal("IELTS plan should unlock IELTS content")
	}
	if SubscriptionGrantsContentAccess("IELTS", "DUOLINGO") {
		t.Fatal("IELTS plan should not unlock Duolingo content")
	}
	if !SubscriptionGrantsContentAccess("DUOLINGO", "DUOLINGO") {
		t.Fatal("DUOLINGO plan should unlock Duolingo content")
	}
}

func TestCalculateSubscriptionExpiresAt_learnEnglishUsesDuration(t *testing.T) {
	start := time.Date(2026, 6, 10, 12, 0, 0, 0, time.UTC)
	got := CalculateSubscriptionExpiresAt(start, "LEARN_ENGLISH", 1, "MONTH")
	want := start.AddDate(0, 1, 0)
	if !got.Equal(want) {
		t.Fatalf("expected %v, got %v", want, got)
	}
}