acdream/src/AcDream.Core/Chat/TurbineChatState.cs

namespace AcDream.Core.Chat;

/// <summary>
/// Runtime state for retail's TurbineChat (0xF7DE) global chat rooms —
/// the General / Trade / LFG / Roleplay / Society / Olthoi pipeline.
///
/// <para>
/// Lifecycle:
/// <list type="bullet">
/// <item>Pre-login: <see cref="Enabled"/> false, all room ids 0, context counter 1.</item>
/// <item>Server fires <c>SetTurbineChatChannels (0x0295)</c> shortly after EnterWorld
///     → <see cref="OnChannelsReceived"/> populates the room ids and flips
///     <see cref="Enabled"/> on.</item>
/// <item>Outbound chat: caller asks for a fresh context id via
///     <see cref="NextContextId"/>, looks up the room id by
///     <see cref="ChatType"/>, and feeds the pair to
///     <see cref="WorldSession.SendTurbineChatTo"/>.</item>
/// </list>
/// </para>
///
/// <para>
/// Mirrors holtburger's <c>TurbineChatState</c>
/// (<c>references/holtburger/crates/holtburger-core/src/client/types.rs</c>
/// lines 657-672). Cookie counter starts at 1 (not 0) per holtburger:
/// <c>next_context_id.wrapping_add(1).max(1)</c> keeps 0 reserved for
/// "no context" / response cookies.
/// </para>
/// </summary>
public sealed class TurbineChatState
{
    /// <summary>True after the first <c>SetTurbineChatChannels</c> arrives.</summary>
    public bool Enabled { get; private set; }

    /// <summary>Allegiance Turbine room (0 if player has no allegiance).</summary>
    public uint AllegianceRoom { get; private set; }
    public uint GeneralRoom { get; private set; }
    public uint TradeRoom { get; private set; }
    public uint LfgRoom { get; private set; }
    public uint RoleplayRoom { get; private set; }
    public uint OlthoiRoom { get; private set; }
    /// <summary>Top-level Society room (0 if player has no society).</summary>
    public uint SocietyRoom { get; private set; }
    public uint SocietyCelestialHandRoom { get; private set; }
    public uint SocietyEldrytchWebRoom { get; private set; }
    public uint SocietyRadiantBloodRoom { get; private set; }

    private uint _nextContextId = 1;

    /// <summary>
    /// Get-and-increment the per-session context cookie. Wraps to 1 (not
    /// 0) so 0 stays reserved for "no context" / Response cookies.
    /// Mirrors holtburger's <c>wrapping_add(1).max(1)</c>.
    /// </summary>
    public uint NextContextId()
    {
        uint cookie = _nextContextId;
        unchecked
        {
            _nextContextId += 1;
            if (_nextContextId == 0) _nextContextId = 1;
        }
        return cookie;
    }

    /// <summary>
    /// Absorb a parsed <c>SetTurbineChatChannels</c> payload — flips
    /// <see cref="Enabled"/> on and fills in the per-channel room ids.
    /// Takes raw u32s (rather than the parser's struct directly) so
    /// AcDream.Core stays free of an AcDream.Core.Net dependency.
    /// </summary>
    public void OnChannelsReceived(
        uint allegianceRoom,
        uint generalRoom,
        uint tradeRoom,
        uint lfgRoom,
        uint roleplayRoom,
        uint olthoiRoom,
        uint societyRoom,
        uint societyCelestialHandRoom,
        uint societyEldrytchWebRoom,
        uint societyRadiantBloodRoom)
    {
        Enabled                  = true;
        AllegianceRoom           = allegianceRoom;
        GeneralRoom              = generalRoom;
        TradeRoom                = tradeRoom;
        LfgRoom                  = lfgRoom;
        RoleplayRoom             = roleplayRoom;
        OlthoiRoom               = olthoiRoom;
        SocietyRoom              = societyRoom;
        SocietyCelestialHandRoom = societyCelestialHandRoom;
        SocietyEldrytchWebRoom   = societyEldrytchWebRoom;
        SocietyRadiantBloodRoom  = societyRadiantBloodRoom;
    }

    /// <summary>
    /// Return the server-assigned room table and outbound context sequence to
    /// their pre-login values. Room ids and cookies belong to one negotiated
    /// character session and must never cross a reconnect boundary.
    /// </summary>
    /// <remarks>
    /// Retail <c>CCommunicationSystem</c> construction at <c>0x005566C0</c>
    /// starts Turbine chat disabled; SetTurbineChatChannels (0x0295) supplies
    /// rooms per character. Cookie 1 is the Holtburger protocol-reference
    /// initial value, with zero reserved for no context.
    /// </remarks>
    public void Reset()
    {
        Enabled = false;
        AllegianceRoom = 0u;
        GeneralRoom = 0u;
        TradeRoom = 0u;
        LfgRoom = 0u;
        RoleplayRoom = 0u;
        OlthoiRoom = 0u;
        SocietyRoom = 0u;
        SocietyCelestialHandRoom = 0u;
        SocietyEldrytchWebRoom = 0u;
        SocietyRadiantBloodRoom = 0u;
        _nextContextId = 1u;
    }

    /// <summary>
    /// Look up the runtime room id for a Turbine
    /// <see cref="ChatChannelKindLite"/>. Returns 0 if the channel is not
    /// available (server hasn't populated it / player not in society / etc).
    /// </summary>
    public uint RoomFor(ChatChannelKindLite kind) => kind switch
    {
        ChatChannelKindLite.Allegiance           => AllegianceRoom,
        ChatChannelKindLite.General              => GeneralRoom,
        ChatChannelKindLite.Trade                => TradeRoom,
        ChatChannelKindLite.Lfg                  => LfgRoom,
        ChatChannelKindLite.Roleplay             => RoleplayRoom,
        ChatChannelKindLite.Olthoi               => OlthoiRoom,
        ChatChannelKindLite.Society              => SocietyRoom,
        ChatChannelKindLite.SocietyCelestialHand => SocietyCelestialHandRoom,
        ChatChannelKindLite.SocietyEldrytchWeb   => SocietyEldrytchWebRoom,
        ChatChannelKindLite.SocietyRadiantBlood  => SocietyRadiantBloodRoom,
        _ => 0u,
    };
}

/// <summary>
/// Coarse Turbine channel selector usable from
/// <see cref="TurbineChatState.RoomFor"/> without dragging in the
/// AcDream.UI.Abstractions <c>ChatChannelKind</c> (which lives in a
/// different layer). Maps 1:1 onto the chat-type-id values from
/// holtburger turbine.rs (TurbineChatType, lines 31-45).
/// </summary>
public enum ChatChannelKindLite
{
    Allegiance,
    General,
    Trade,
    Lfg,
    Roleplay,
    Society,
    SocietyCelestialHand,
    SocietyEldrytchWeb,
    SocietyRadiantBlood,
    Olthoi,
}