using Arch.Core;
using HSchool.Ai;
using HSchool.Content;
using HSchool.People;
using HSchool.Schedule;

namespace HSchool.Simulation.Tests;

public class GradeTrailCouplingTests
{
    private static readonly DateTime TuesdayMorning = new(2012, 4, 3, 6, 0, 0, DateTimeKind.Utc);
    private static readonly DateTime LessonStart = new(2012, 4, 3, 8, 30, 0, DateTimeKind.Utc);

    [Fact]
    public void WhisperOnLesson_MarkWorseThanQuiet()
    {
        var quiet = RunMathMark(whisper: false);
        var whispered = RunMathMark(whisper: true);
        Assert.True(quiet > whispered);
    }

    [Fact]
    public void NoTextbook_MarkWorseThanWithTextbook()
    {
        var withBook = RunMathMark(whisper: false, textbook: true);
        var without = RunMathMark(whisper: false, textbook: false);
        Assert.True(withBook > without);
    }

    [Fact]
    public void PoorMarkTrail_EmitsNotice()
    {
        var (school, _, pupilId, _) = StaffedMath();
        using (school)
        {
            var rules = school.Catalog!.BehaviorRules!;
            var person = school.Roster!.People.First(row => row.Id == pupilId);
            var t0 = LessonStart;
            Assert.True(LessonMarkMemory.Record(person, "Mathematics", 2, t0, 1, rules));
            Assert.True(LessonMarkMemory.Record(person, "Literature", 2, t0.AddHours(1), 2, rules));
            Assert.True(LessonMarkMemory.Record(person, "History", 2, t0.AddHours(2), 3, rules));

            school.DrainWorldEvents();
            GradeTrailSystem.AfterMark(school, person);

            Assert.Contains(
                school.DrainWorldEvents(),
                row => row.Trigger.Equals(EventTriggers.PoorGradeTrail, StringComparison.Ordinal)
                    && row.PersonKey.Equals(pupilId, StringComparison.Ordinal));
        }
    }

    [Fact]
    public void IllnessAbsent_DoesNotAddTruancyOffense()
    {
        var (school, _, pupilId, _) = StaffedMath();
        using (school)
        {
            var person = school.Roster!.People.First(row => row.Id == pupilId);
            person.Offenses = null;
            GradeTrailSystem.AfterAbsent(school, person, AbsenceReasons.Illness);
            Assert.True(person.Offenses is null || person.Offenses.Count == 0);

            GradeTrailSystem.AfterAbsent(school, person, AbsenceReasons.Truancy);
            Assert.NotNull(person.Offenses);
            Assert.Contains(person.Offenses!, row => row.Kind == OffenseKinds.Truancy);
        }
    }

    private static int RunMathMark(bool whisper, bool textbook = true)
    {
        var (school, room, pupilId, teacherId) = StaffedMath();
        using (school)
        {
            AdvanceTo(school, LessonStart);
            school.ResetDayLog();
            var pupil = school.Roster!.People.First(row => row.Id == pupilId);
            pupil.LessonMarks = null;

            SetPlace(school, pupilId, room);
            SetPlace(school, teacherId, room);
            SetSkill(school, teacherId, "Mathematics", 100f);
            SetNeed(school, pupilId, "Hunger", 1f);
            SetNeed(school, pupilId, "Warmth", 1f);
            if (textbook)
            {
                PlaceTextbook(school, pupilId, "Mathematics");
            }
            else
            {
                ClearTextbooks(school, pupilId);
            }

            if (whisper)
            {
                var partner = school.Roster!.Classes
                    .SelectMany(row => row.PupilIds)
                    .First(id => id != pupilId);
                SetPlace(school, partner, room);
                PlaceTextbook(school, partner, "Mathematics");
                Assert.True(school.TryStartAction(pupilId, TalkActions.Whisper));
            }

            LessonLearningSystem.Apply(school, 45);
            var mark = MarkOf(school, pupilId);
            Assert.NotNull(mark);
            return mark!.Value;
        }
    }

    private static LessonMarkRecord? MarkOf(School school, string pupilId) =>
        school.Roster!.People.First(row => row.Id == pupilId).LessonMarks?.LastOrDefault();

    private static (School School, string Homeroom, string PupilId, string TeacherId) StaffedMath()
    {
        var (catalog, map) = Vanilla();
        var roster = RosterGenerator.Generate(catalog, map, schoolSeed: 1, "Russia", TuesdayMorning);
        var pool = ApplicantPool.Create(catalog, roster, schoolSeed: 1, "Russia", TuesdayMorning);
        var hired = Staffing.Hire(catalog, map, roster, pool, pool.Applicants[0].Person.Id, Staffing.TeacherPosition, 1_000_000f);
        Assert.Equal(StaffingError.None, hired.Error);
        roster = hired.Roster;
        pool = hired.Pool;
        var hiredId = roster.People.First(person => person.IsStaff).Id;
        var schoolClass = roster.Classes.First(row =>
            row.RoomId is "classroom-101" or "classroom-102" or "classroom-103" or "classroom-104");
        var school = School.Create(1, "Стык", TuesdayMorning, catalog, map);
        school.InstallPeople(roster, seed: 1, "Russia", pool);
        school.SetTimetable(new Timetable(
            [new LessonPlacement(schoolClass.Id, "Mathematics", hiredId, schoolClass.RoomId, Day: 1, Period: 1)],
            []));
        school.ConfigurePresence(weekDays: 5, maxDecisionsPerTick: 10_000);
        var pupil = schoolClass.PupilIds
            .Select(id => school.Roster!.People.First(person => person.Id == id))
            .First(person => !person.Traits.Contains("Lazy"));
        return (school, schoolClass.RoomId, pupil.Id, hiredId);
    }

    private static void PlaceTextbook(School school, string personId, string subject, string location = ItemLocations.Bag)
    {
        var person = school.Roster!.People.First(row => row.Id.Equals(personId, StringComparison.Ordinal));
        if (person.Items is not IList<InventoryItem> items || items.IsReadOnly)
        {
            throw new InvalidOperationException($"Cannot mutate items for {personId}.");
        }

        ClearTextbooks(school, personId);
        items.Add(new InventoryItem("Textbook", Color: null, Condition: 1f, location, subject));
    }

    private static void ClearTextbooks(School school, string personId)
    {
        var person = school.Roster!.People.First(row => row.Id.Equals(personId, StringComparison.Ordinal));
        if (person.Items is not IList<InventoryItem> items || items.IsReadOnly)
        {
            throw new InvalidOperationException($"Cannot mutate items for {personId}.");
        }

        for (var i = items.Count - 1; i >= 0; i--)
        {
            if (items[i].Subject is not null)
            {
                items.RemoveAt(i);
            }
        }
    }

    private static void AdvanceTo(School school, DateTime until)
    {
        while (school.Clock.Time < until)
        {
            school.Tick(0.2d, 5d);
        }
    }

    private static void SetPlace(School school, string personId, string node, string[]? path = null, float remaining = 0f)
    {
        TalkCircleSystem.Interrupt(school, personId);
        school.TalkCircleByPerson.Remove(personId);
        var query = new QueryDescription().WithAll<PersonIdentity, Presence, PersonActivity, Intent>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref Presence presence, ref PersonActivity activity, ref Intent intent) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    presence = new Presence(node, remaining, node, HeadingHome: false, path ?? []);
                    activity = PersonActivity.Idle;
                    intent = Intent.None;
                }
            });
    }

    private static void SetSkill(School school, string personId, string skill, float value)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, PersonSkills>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonSkills skills) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    skills.Values[skill] = value;
                }
            });
    }

    private static void SetNeed(School school, string personId, string need, float value)
    {
        var query = new QueryDescription().WithAll<PersonIdentity, PersonNeeds>();
        school.World.Query(
            in query,
            (ref PersonIdentity identity, ref PersonNeeds needs) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    needs.Values[need] = value;
                }
            });
    }

    private static (DefCatalog Catalog, MapLayout Map) Vanilla()
    {
        var root = Path.Combine(AppContext.BaseDirectory, "vanilla");
        var documents = new List<ContentDocument>();
        foreach (var path in Directory.EnumerateFiles(root, "*.*", SearchOption.AllDirectories))
        {
            if (!path.EndsWith(".jsonc", StringComparison.OrdinalIgnoreCase)
                && !path.EndsWith(".json", StringComparison.OrdinalIgnoreCase))
            {
                continue;
            }

            var relative = Path.GetRelativePath(root, path).Replace('\\', '/');
            documents.Add(new ContentDocument(CatalogLoader.CorePackId, relative, File.ReadAllText(path)));
        }

        var catalog = new CatalogLoader().Load([CatalogLoader.CorePackId], documents);
        var map = CatalogLoader.LastDefaultMap([CatalogLoader.CorePackId], documents);
        Assert.NotNull(map);
        return (catalog, map);
    }
}