namespace HSchool.People;

/// <summary>Plain roster data. Simulation turns these into entities; this project does not.</summary>
public sealed record Roster(
    IReadOnlyList<Person> People,
    IReadOnlyList<Family> Families,
    IReadOnlyList<SchoolClass> Classes);

public sealed record Person
{
    public required string Id { get; init; }

    public required string FamilyId { get; init; }

    public required bool Female { get; init; }

    public required DateTime BirthDate { get; init; }

    public required PersonName Name { get; init; }

    public required bool IsStudent { get; init; }

    public required bool IsStaff { get; init; }

    public required bool IsParent { get; init; }

    public string? ClassId { get; init; }

    public string? Position { get; init; }

    public string? WorkplaceRoomId { get; init; }

    public required IReadOnlyDictionary<string, int> Numbers { get; init; }

    public required IReadOnlyDictionary<string, string> Choices { get; init; }

    public required IReadOnlyDictionary<string, int> Skills { get; init; }

    public required IReadOnlyList<string> Traits { get; init; }

    public required IReadOnlyDictionary<string, float> Needs { get; init; }

    /// <summary>SubjectDef names this staff member is assigned. Empty for everyone else.</summary>
    public IReadOnlyList<string> Subjects { get; init; } = [];

    /// <summary>Hourly rate frozen at hire. Null until the person is staff.</summary>
    public float? HourlyWageAsk { get; init; }

    /// <summary>Worn, bag, locker and home. Empty on rosters written before clothes existed.</summary>
    public IReadOnlyList<InventoryItem> Items { get; init; } = [];

    public int AgeOn(DateTime asOf) => SchoolYears.AgeYears(BirthDate, asOf);
}

public sealed record PersonName(
    string Given,
    string Surname,
    string Patronymic,
    CaseTable GivenCases,
    CaseTable SurnameCases,
    CaseTable PatronymicCases)
{
    /// <summary>Nominative ФИО as the list and cards show it: surname, given, patronymic.</summary>
    public string Full => string.Join(' ', new[] { Surname, Given, Patronymic }.Where(part => part.Length > 0));
}

/// <summary>
/// A household. <see cref="ParentIds"/> holds one adult or two — a child keeps the father's
/// surname and patronymic whether or not the father lives with them, so both are recorded here
/// rather than read off a parent who may not be in the roster.
/// </summary>
public sealed record Family(
    string Id,
    IReadOnlyList<string> ParentIds,
    IReadOnlyList<string> ChildIds,
    int NextChild = 0,
    string FatherGiven = "",
    string Surname = "")
{
    /// <summary>
    /// Id suffix for the next child of this family. It is a counter and not
    /// <c>ChildIds.Count</c>, because a graduate leaves the roster: deriving the suffix from the
    /// children still present would hand a newcomer the id of the person who just left, and every
    /// family link and open card pointing at that id would silently follow the wrong person.
    ///
    /// Rosters written before the counter existed fall back to the highest suffix still present.
    /// </summary>
    public int NextChildIndex => Math.Max(NextChild, HighestChildSuffix() + 1);

    private int HighestChildSuffix()
    {
        var highest = -1;
        foreach (var id in ChildIds)
        {
            var marker = id.LastIndexOf(".c", StringComparison.Ordinal);
            if (marker >= 0 && int.TryParse(id.AsSpan(marker + 2), out var index) && index > highest)
            {
                highest = index;
            }
        }

        return highest;
    }
}

public sealed record SchoolClass(
    string Id,
    int Year,
    string Letter,
    string RoomId,
    int Capacity,
    IReadOnlyList<string> PupilIds);