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

namespace HSchool.Simulation;

internal sealed class ActiveTalkCircle
{
    public required string Id { get; init; }

    public required string ActionId { get; init; }

    public required string TopicId { get; init; }

    public required string NodeId { get; init; }

    public required List<string> Members { get; init; }

    public float RemainingMinutes { get; set; }

    /// <summary>Set once a teacher in the room has rolled to notice this whisper.</summary>
    public bool CatchChecked { get; set; }
}

/// <summary>Forms 2–4 person talk circles, applies outcomes, writes topic log lines.</summary>
internal static class TalkCircleSystem
{
    private static readonly QueryDescription People =
        new QueryDescription().WithAll<PersonIdentity, PersonRoles, PersonTraits, PersonSkills, PersonNeeds, Presence, PersonActivity>();

    public static bool IsInCircle(School school, string personId) =>
        school.TalkCircleByPerson.ContainsKey(personId);

    /// <summary>Ends an active circle when duty overrides break talk (bell rang).</summary>
    public static void Interrupt(School school, string personId)
    {
        if (!school.TalkCircleByPerson.TryGetValue(personId, out var circleId)
            || !school.TalkCirclesById.TryGetValue(circleId, out var circle))
        {
            return;
        }

        Finish(school, circle);
    }

    public static bool TryStart(School school, string personId, string actionId)
    {
        if (school.Catalog is null || school.Map is null || school.Roster is null)
        {
            return false;
        }

        if (!TalkActions.IsTalk(actionId) || !school.Catalog.Actions.TryGetValue(actionId, out var action) || action.Abstract)
        {
            return false;
        }

        if (school.TalkCircleByPerson.ContainsKey(personId))
        {
            return true;
        }

        var person = school.Roster.People.FirstOrDefault(row => row.Id.Equals(personId, StringComparison.Ordinal));
        if (person is null || !RoleFits(action, person))
        {
            return false;
        }

        string? nodeId = null;
        var busy = false;
        school.World.Query(in People, (ref PersonIdentity identity, ref Presence presence, ref PersonActivity activity) =>
        {
            if (!identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                return;
            }

            nodeId = presence.NodeId;
            busy = activity.IsActive;
        });

        if (nodeId is null || busy)
        {
            return false;
        }

        var location = school.Map.NodeDef(nodeId);
        if (location is null || !location.Equals(action.Room, StringComparison.Ordinal))
        {
            return false;
        }

        if (action.DefName.Equals(TalkActions.PhoneChat, StringComparison.Ordinal))
        {
            return TryStartPhone(school, person, nodeId, action);
        }

        var existing = FindOpenCircle(school, nodeId, actionId);
        if (existing is not null)
        {
            return JoinCircle(school, existing, personId, action);
        }

        return TryStartGroup(school, person, nodeId, action);
    }

    public static IReadOnlyList<string> Apply(School school, double gameMinutes)
    {
        if (gameMinutes <= 0 || school.Catalog is null || school.Roster is null)
        {
            return [];
        }

        var minutes = (float)gameMinutes;
        var completed = new List<string>();
        foreach (var circle in school.TalkCirclesById.Values.ToArray())
        {
            circle.RemainingMinutes -= minutes;
            SyncActivity(school, circle);
            if (TalkActions.IsWhisper(circle.ActionId) && TryCatchWhisper(school, circle))
            {
                continue;
            }

            if (circle.RemainingMinutes > 0)
            {
                continue;
            }

            Finish(school, circle);
            completed.AddRange(circle.Members);
        }

        completed.Sort(StringComparer.Ordinal);
        return completed;
    }

    private static bool TryStartPhone(School school, Person initiator, string nodeId, ActionDef action)
    {
        if (!TalkCircles.HasPhone(initiator.Items))
        {
            return false;
        }

        var candidates = GatherCandidates(school, initiator.Id, nodeId, requirePhone: true);
        var ranked = TalkCircles.RankInvitees(initiator, candidates, school.Catalog!.BehaviorRules);
        if (ranked.Count == 0)
        {
            return false;
        }

        var partnerId = ranked[0];
        var partner = school.Roster!.People.First(row => row.Id.Equals(partnerId, StringComparison.Ordinal));
        if (!TalkCircles.HasPhone(partner.Items))
        {
            return false;
        }

        var topicId = TalkCircles.PickTopic(
            school.Catalog!,
            initiator,
            initiator.AgeOn(school.Clock.Time),
            Seed.Mix(school.PeopleSeed, initiator.Id, DateOnly.FromDateTime(school.Clock.Time).DayNumber, Seed.ApparelSalt + 20))
            ?? school.Catalog!.Topics.Values.First(topic => !topic.Abstract).DefName;

        var circle = new ActiveTalkCircle
        {
            Id = $"phone-{initiator.Id}-{partnerId}",
            ActionId = action.DefName,
            TopicId = topicId,
            NodeId = nodeId,
            Members = [initiator.Id, partnerId],
            RemainingMinutes = action.Minutes,
        };
        Register(school, circle, action);
        return true;
    }

    private static bool TryStartGroup(School school, Person initiator, string nodeId, ActionDef action)
    {
        var rules = school.Catalog!.BehaviorRules;
        var max = TalkCircles.MaxSize(action.DefName, rules, initiator.Traits, school.Catalog);
        var studentsOnly = TalkActions.IsWhisper(action.DefName) || TalkActions.IsTeacherTalk(action.DefName);
        var candidates = GatherCandidates(school, initiator.Id, nodeId, requirePhone: false, studentsOnly);
        var ranked = TalkCircles.RankInvitees(initiator, candidates, rules);
        var members = new List<string> { initiator.Id };
        foreach (var id in ranked)
        {
            if (members.Count >= max)
            {
                break;
            }

            members.Add(id);
        }

        var min = TalkActions.IsTeacherTalk(action.DefName) ? 3 : rules?.TalkCircleMin ?? 2;
        if (members.Count < min)
        {
            return false;
        }

        var topicId = TalkCircles.PickTopic(
            school.Catalog,
            initiator,
            initiator.AgeOn(school.Clock.Time),
            Seed.Mix(school.PeopleSeed, initiator.Id, DateOnly.FromDateTime(school.Clock.Time).DayNumber, Seed.ApparelSalt + 21),
            whisperOnLesson: TalkActions.IsWhisper(action.DefName));
        if (TalkActions.IsTeacherTalk(action.DefName))
        {
            topicId = TalkCircles.PickTeacherTopic(
                school.Catalog,
                rules,
                Seed.Mix(school.PeopleSeed, initiator.Id, DateOnly.FromDateTime(school.Clock.Time).DayNumber, Seed.WhisperSalt));
        }

        topicId ??= school.Catalog.Topics.Values.First(topic => !topic.Abstract).DefName;

        var circle = new ActiveTalkCircle
        {
            Id = $"talk-{initiator.Id}-{nodeId}-{school.Clock.Time.Ticks}",
            ActionId = action.DefName,
            TopicId = topicId,
            NodeId = nodeId,
            Members = members,
            RemainingMinutes = action.Minutes,
        };
        Register(school, circle, action);
        return true;
    }

    private static bool JoinCircle(School school, ActiveTalkCircle circle, string personId, ActionDef action)
    {
        var rules = school.Catalog!.BehaviorRules;
        var person = school.Roster!.People.First(row => row.Id.Equals(personId, StringComparison.Ordinal));
        if ((TalkActions.IsWhisper(action.DefName) || TalkActions.IsTeacherTalk(action.DefName)) && !person.IsStudent)
        {
            return false;
        }

        var max = TalkCircles.MaxSize(action.DefName, rules, person.Traits, school.Catalog);
        if (circle.Members.Count >= max || circle.Members.Contains(personId))
        {
            return false;
        }

        circle.Members.Add(personId);
        circle.Members.Sort(StringComparer.Ordinal);
        school.TalkCircleByPerson[personId] = circle.Id;
        SetActivity(school, personId, action.DefName, circle.TopicId, circle.RemainingMinutes);
        return true;
    }

    private static ActiveTalkCircle? FindOpenCircle(School school, string nodeId, string actionId)
    {
        foreach (var circle in school.TalkCirclesById.Values)
        {
            if (circle.NodeId.Equals(nodeId, StringComparison.Ordinal)
                && circle.ActionId.Equals(actionId, StringComparison.Ordinal)
                && circle.RemainingMinutes > 0)
            {
                var rules = school.Catalog!.BehaviorRules;
                var max = TalkCircles.MaxSize(actionId, rules, [], school.Catalog);
                if (circle.Members.Count < max)
                {
                    return circle;
                }
            }
        }

        return null;
    }

    private static IReadOnlyList<TalkCircles.Candidate> GatherCandidates(
        School school,
        string exceptId,
        string nodeId,
        bool requirePhone,
        bool studentsOnly = false)
    {
        var roster = school.Roster!.People.ToDictionary(person => person.Id, StringComparer.Ordinal);
        var list = new List<TalkCircles.Candidate>();
        school.World.Query(
            in People,
            (ref PersonIdentity identity, ref PersonRoles roles, ref Presence presence, ref PersonActivity activity) =>
            {
                if (identity.Id.Equals(exceptId, StringComparison.Ordinal)
                    || presence.NodeId is null
                    || !presence.NodeId.Equals(nodeId, StringComparison.Ordinal))
                {
                    return;
                }

                if (studentsOnly && !roles.IsStudent)
                {
                    return;
                }

                if (!roster.TryGetValue(identity.Id, out var person))
                {
                    return;
                }

                if (requirePhone && !TalkCircles.HasPhone(person.Items))
                {
                    return;
                }

                list.Add(new TalkCircles.Candidate(
                    identity.Id,
                    roles.ClassId,
                    !activity.IsActive && !school.TalkCircleByPerson.ContainsKey(identity.Id),
                    school.TalkCircleByPerson.ContainsKey(identity.Id),
                    TalkCircles.HasPhone(person.Items)));
            });

        return list.Where(candidate => candidate.IsIdle).ToArray();
    }

    private static void Register(School school, ActiveTalkCircle circle, ActionDef action)
    {
        school.TalkCirclesById[circle.Id] = circle;
        foreach (var member in circle.Members)
        {
            school.TalkCircleByPerson[member] = circle.Id;
            SetActivity(school, member, action.DefName, circle.TopicId, circle.RemainingMinutes);
            if (TalkActions.IsWhisper(action.DefName))
            {
                school.AppendDayLog(new PersonLogEvent(
                    member,
                    school.Clock.Time,
                    PersonLogTypes.Whispered,
                    circle.TopicId));
            }
        }
    }

    private static void SetActivity(School school, string personId, string actionId, string topicId, float remaining)
    {
        school.World.Query(
            in People,
            (ref PersonIdentity identity, ref PersonActivity activity) =>
            {
                if (identity.Id.Equals(personId, StringComparison.Ordinal))
                {
                    activity = new PersonActivity(actionId, topicId, remaining);
                }
            });
    }

    private static void SyncActivity(School school, ActiveTalkCircle circle)
    {
        foreach (var member in circle.Members)
        {
            SetActivity(school, member, circle.ActionId, circle.TopicId, Math.Max(0f, circle.RemainingMinutes));
        }
    }

    private static void Finish(School school, ActiveTalkCircle circle)
    {
        var catalog = school.Catalog!;
        var rules = catalog.BehaviorRules;
        var roster = school.Roster!;
        var people = circle.Members
            .Select(id => roster.People.First(person => person.Id.Equals(id, StringComparison.Ordinal)))
            .ToArray();
        if (!catalog.Topics.TryGetValue(circle.TopicId, out var topic))
        {
            topic = catalog.Topics.Values.First(def => !def.Abstract);
        }

        if (!catalog.Actions.TryGetValue(circle.ActionId, out var action))
        {
            action = catalog.Actions[TalkActions.Chat];
        }

        var hours = action.Minutes / 60f;
        var sharedLanguage = TalkCircles.SharedLanguage(catalog, people, rules) is not null;
        var language = TalkCircles.SharedLanguage(catalog, people, rules);

        foreach (var person in people)
        {
            if (!string.IsNullOrWhiteSpace(action.Need)
                && catalog.Needs.TryGetValue(action.Need, out var need))
            {
                var current = NeedOf(school, person.Id, action.Need);
                if (float.IsNaN(current))
                {
                    current = need.Min;
                }

                var next = ActionStepper.ApplyNeedGain(current, action, need);
                MutateNeed(school, person.Id, action.Need, next);
            }

            if (catalog.Skills.TryGetValue("Communication", out var communicationSkill))
            {
                var level = SkillOf(school, person.Id, "Communication");
                var next = TalkCircles.CommunicationGain(level, communicationSkill, hours, rules);
                MutateSkill(school, person.Id, "Communication", next);
            }

            if (language is not null
                && catalog.Skills.TryGetValue(language, out var languageSkill)
                && SkillOf(school, person.Id, language) < languageSkill.Range.Max)
            {
                var level = SkillOf(school, person.Id, language);
                var next = TalkCircles.LanguageGain(level, languageSkill, hours, rules);
                MutateSkill(school, person.Id, language, next);
            }

            foreach (var other in people)
            {
                if (other.Id.Equals(person.Id, StringComparison.Ordinal))
                {
                    continue;
                }

                var communication = SkillOf(school, person.Id, "Communication");
                var appearance = AppearanceOf(school, other);
                var delta = TalkCircles.OpinionDelta(
                    person,
                    other,
                    topic,
                    communication,
                    sharedLanguage,
                    circle.ActionId,
                    appearance,
                    rules,
                    catalog);
                if (person.IsStudent && other.IsStaff)
                {
                    delta = TalkCircles.ScaleByPedagogy(delta, SkillOf(school, other.Id, "Pedagogy"), rules);
                }

                if (delta == 0)
                {
                    continue;
                }

                var current = OpinionStore.Get(person, other.Id) ?? 0;
                OpinionStore.Set(person, other.Id, current + delta);
            }

            school.AppendDayLog(new PersonLogEvent(
                person.Id,
                school.Clock.Time,
                PersonLogTypes.TalkEnded,
                circle.TopicId));
        }

        foreach (var member in circle.Members)
        {
            school.TalkCircleByPerson.Remove(member);
            ClearActivity(school, member);
        }

        school.TalkCirclesById.Remove(circle.Id);
    }

    private static bool TryCatchWhisper(School school, ActiveTalkCircle circle)
    {
        if (circle.CatchChecked)
        {
            return false;
        }

        var teacherId = StaffStandingIn(school, circle.NodeId);
        if (teacherId is null)
        {
            return false;
        }

        circle.CatchChecked = true;
        var rules = school.Catalog!.BehaviorRules;
        var traits = new List<string>();
        foreach (var memberId in circle.Members)
        {
            var member = school.Roster!.People.FirstOrDefault(person => person.Id.Equals(memberId, StringComparison.Ordinal));
            if (member is not null)
            {
                traits.AddRange(member.Traits);
            }
        }

        var roll = TalkCircles.Roll01(
            Seed.Mix(school.PeopleSeed, circle.Id, DateOnly.FromDateTime(school.Clock.Time).DayNumber, Seed.WhisperSalt));
        var multiplier = TalkCircles.WhisperCatchMultiplier(traits, school.Catalog);
        if (!TalkCircles.WhisperCaught(
                roll,
                rules?.WhisperCatchChance ?? 0.4f,
                rules?.WhisperCatchMax ?? 0.85f,
                multiplier))
        {
            return false;
        }

        ConvertToReprimand(school, circle, teacherId);
        return true;
    }

    private static void ConvertToReprimand(School school, ActiveTalkCircle circle, string teacherId)
    {
        var pupils = circle.Members.ToArray();
        foreach (var member in pupils)
        {
            school.AppendDayLog(new PersonLogEvent(
                member,
                school.Clock.Time,
                PersonLogTypes.TeacherInterrupted,
                circle.TopicId));
            school.TalkCircleByPerson.Remove(member);
            ClearActivity(school, member);
        }

        school.TalkCirclesById.Remove(circle.Id);
        if (!school.Catalog!.Actions.TryGetValue(TalkActions.TeacherTalk, out var action))
        {
            return;
        }

        var members = new List<string> { teacherId };
        var max = TalkCircles.MaxSize(TalkActions.TeacherTalk, school.Catalog.BehaviorRules, [], school.Catalog);
        foreach (var id in pupils.OrderBy(value => value, StringComparer.Ordinal))
        {
            if (members.Count >= max)
            {
                break;
            }

            if (!members.Contains(id, StringComparer.Ordinal))
            {
                members.Add(id);
            }
        }

        if (members.Count < 3)
        {
            return;
        }

        var reprimand = new ActiveTalkCircle
        {
            Id = $"reprimand-{teacherId}-{circle.NodeId}-{school.Clock.Time.Ticks}",
            ActionId = TalkActions.TeacherTalk,
            TopicId = TeacherTopics.Discipline,
            NodeId = circle.NodeId,
            Members = members,
            RemainingMinutes = action.Minutes,
            CatchChecked = true,
        };
        Register(school, reprimand, action);
    }

    private static string? StaffStandingIn(School school, string nodeId)
    {
        string? found = null;
        school.World.Query(
            in People,
            (ref PersonIdentity identity, ref PersonRoles roles, ref Presence presence, ref PersonActivity activity) =>
            {
                if (found is not null
                    || !roles.IsStaff
                    || presence.NodeId is null
                    || !presence.NodeId.Equals(nodeId, StringComparison.Ordinal)
                    || presence.Path.Length > 0
                    || presence.RemainingMinutes > 0)
                {
                    return;
                }

                found = identity.Id;
            });
        return found;
    }

    private static bool RoleFits(ActionDef action, Person person)
    {
        if (action.Roles.Count == 0)
        {
            return true;
        }

        foreach (var role in action.Roles)
        {
            if (role.Equals(HSchool.Content.PersonRoles.Student, StringComparison.OrdinalIgnoreCase) && person.IsStudent)
            {
                return true;
            }

            if (role.Equals(HSchool.Content.PersonRoles.Staff, StringComparison.OrdinalIgnoreCase) && person.IsStaff)
            {
                return true;
            }

            if (role.Equals(HSchool.Content.PersonRoles.Parent, StringComparison.OrdinalIgnoreCase) && person.IsParent)
            {
                return true;
            }
        }

        return false;
    }

    private static ApparelIssue AppearanceOf(School school, Person person)
    {
        var schoolClass = person.ClassId is { } classId
            ? school.Roster!.Classes.FirstOrDefault(row => row.Id.Equals(classId, StringComparison.Ordinal))
            : null;
        var mode = ApparelPresence.ModeAt(school, person, schoolClass);
        return ApparelDresser.CurrentIssues(school, person, mode);
    }

    private static float NeedOf(School school, string personId, string need)
    {
        var value = float.NaN;
        school.World.Query(in People, (ref PersonIdentity identity, ref PersonNeeds needs) =>
        {
            if (identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                value = needs.Values.GetValueOrDefault(need, float.NaN);
            }
        });
        return value;
    }

    private static float SkillOf(School school, string personId, string skill)
    {
        var value = 0f;
        school.World.Query(in People, (ref PersonIdentity identity, ref PersonSkills skills) =>
        {
            if (identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                value = skills.Values.GetValueOrDefault(skill);
            }
        });
        return value;
    }

    private static void MutateSkill(School school, string personId, string skill, float value)
    {
        school.World.Query(in People, (ref PersonIdentity identity, ref PersonSkills skills) =>
        {
            if (identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                skills.Values[skill] = value;
            }
        });
    }

    private static void MutateNeed(School school, string personId, string need, float value)
    {
        school.World.Query(in People, (ref PersonIdentity identity, ref PersonNeeds needs) =>
        {
            if (identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                needs.Values[need] = value;
            }
        });
    }

    private static void ClearActivity(School school, string personId)
    {
        school.World.Query(in People, (ref PersonIdentity identity, ref PersonActivity activity) =>
        {
            if (identity.Id.Equals(personId, StringComparison.Ordinal))
            {
                activity = PersonActivity.Idle;
            }
        });
    }
}