import 'package:flutter_test/flutter_test.dart';
import 'package:life_helper/domain/models/habit.dart';
import 'package:life_helper/domain/recommend/recommend_variant.dart';

HabitModel _habit(List<HabitDoseVariantModel> variants) => HabitModel(
      id: 'hb_x',
      userId: 'u_local_default',
      type: HabitType.build,
      status: HabitStatus.active,
      title: 't',
      protocolId: 'p',
      frameLevel: FrameLevel.l2,
      frameFramedText: 't',
      startedAt: '2026-06-01',
      doseVariants: variants,
    );

HabitDoseVariantModel _v({
  required String id,
  required int sort,
  bool isMin = false,
  List<String> ctx = const [],
  List<String> cond = const [],
}) =>
    HabitDoseVariantModel(
      variantId: id,
      habitId: 'hb_x',
      label: id,
      doseText: '1x',
      contextTags: ctx,
      conditionTags: cond,
      isMinimum: isMin,
      sortOrder: sort,
    );

void main() {
  test('empty variants → null', () {
    expect(recommendVariant(_habit(const []), const CheckInContext()), isNull);
  });

  test('exact match wins (location + condition, score 4)', () {
    final habit = _habit([
      _v(id: 'A', sort: 0, ctx: ['집']),
      _v(id: 'B', sort: 1, ctx: ['회사'], cond: ['좋음']),
      _v(id: 'C', sort: 2, isMin: true),
    ]);
    final pick = recommendVariant(
        habit, const CheckInContext(location: '회사', condition: '좋음'));
    expect(pick!.variant.variantId, 'B');
    expect(pick.reason, RecommendReason.exactMatch);
    expect(pick.score, 4);
  });

  test('partial match (only location)', () {
    final habit = _habit([
      _v(id: 'A', sort: 0, ctx: ['집']),
      _v(id: 'B', sort: 1, ctx: ['회사']),
    ]);
    final pick = recommendVariant(habit, const CheckInContext(location: '집'));
    expect(pick!.variant.variantId, 'A');
    expect(pick.reason, RecommendReason.partial);
    expect(pick.score, 2);
  });

  test('fallback to minimum when nothing matches', () {
    final habit = _habit([
      _v(id: 'A', sort: 0, ctx: ['집']),
      _v(id: 'B', sort: 1, isMin: true),
    ]);
    final pick = recommendVariant(
        habit, const CheckInContext(location: '카페', condition: '나쁨'));
    // is_minimum + condition=='나쁨' → score 1 → partial pick, not fallback.
    expect(pick!.variant.variantId, 'B');
    expect(pick.reason, RecommendReason.partial);
  });

  test('fallback to first by sortOrder when no minimum, no match', () {
    final habit = _habit([
      _v(id: 'A', sort: 5, ctx: ['집']),
      _v(id: 'B', sort: 2, ctx: ['회사']),
    ]);
    final pick = recommendVariant(habit, const CheckInContext(location: '카페'));
    expect(pick!.variant.variantId, 'B');
    expect(pick.reason, RecommendReason.fallbackFirst);
    expect(pick.score, 0);
  });

  test('tie-break: same score → smaller sortOrder wins', () {
    final habit = _habit([
      _v(id: 'A', sort: 10, ctx: ['집']),
      _v(id: 'B', sort: 1, ctx: ['집']),
    ]);
    final pick = recommendVariant(habit, const CheckInContext(location: '집'));
    expect(pick!.variant.variantId, 'B');
  });
}