feat: Implemented area chat

Author: ycastorium

.gitignore

@@ -8,6 +8,7 @@ rathena.xml
 .DS_Store
 .mnesia
 .memory_bank
+.claude_consciousness.m8
 
 apps/zone_server/priv/db/rathena
 

apps/zone_server/lib/aesir/zone_server/packet_registry.ex

@@ -10,9 +10,11 @@ defmodule Aesir.ZoneServer.PacketRegistry do
     Aesir.ZoneServer.Packets.CzReqname2,
     Aesir.ZoneServer.Packets.CzSeCashshopList,
     Aesir.ZoneServer.Packets.CzPingLive,
+    Aesir.ZoneServer.Packets.CzRequestChat,
     # Server to Client packets
     Aesir.ZoneServer.Packets.ZcAcceptEnter,
     Aesir.ZoneServer.Packets.ZcAid,
+    Aesir.ZoneServer.Packets.ZcNotifyChat,
     Aesir.ZoneServer.Packets.ZcAckReqname,
     Aesir.ZoneServer.Packets.ZcNotifyTime,
     Aesir.ZoneServer.Packets.ZcNotifyTime2,

apps/zone_server/lib/aesir/zone_server/packets/cz_request_chat.ex

@@ -0,0 +1,40 @@
+defmodule Aesir.ZoneServer.Packets.CzRequestChat do
+  @moduledoc """
+  Client to Server: Request to send a normal chat message.
+  Packet ID: 0x008c
+  """
+
+  use Aesir.Commons.Network.Packet
+  use TypedStruct
+
+  @packet_id 0x008C
+  @packet_size :variable
+  @packet_size_header 4
+
+  typedstruct do
+    @typedoc "Client chat message request"
+    field :message, String.t()
+  end
+
+  @impl true
+  def packet_id, do: @packet_id
+
+  @impl true
+  def packet_size, do: @packet_size
+
+  @impl true
+  def parse(
+        <<@packet_id::16-little, packet_length::16-little,
+          message_data::binary-size(packet_length - @packet_size_header)>>
+      ) do
+    message = message_data |> to_string() |> String.trim_trailing("\0")
+    {:ok, %__MODULE__{message: message}}
+  end
+
+  def parse(_), do: {:error, :invalid_packet}
+
+  @impl true
+  def build(%__MODULE__{} = _packet) do
+    raise "CzRequestChat is a client-to-server packet and should not be built by the server."
+  end
+end

apps/zone_server/lib/aesir/zone_server/packets/zc_notify_chat.ex

@@ -0,0 +1,45 @@
+defmodule Aesir.ZoneServer.Packets.ZcNotifyChat do
+  @moduledoc """
+  Server to Client: Notifies clients of a chat message in the area.
+  Packet ID: 0x008d
+  """
+
+  use Aesir.Commons.Network.Packet
+  use TypedStruct
+
+  @packet_id 0x008D
+  @packet_size :variable
+  @packet_size_header 4
+
+  typedstruct do
+    @typedoc "Chat message broadcast to clients"
+    field :gid, non_neg_integer()
+    field :message, String.t()
+  end
+
+  @impl true
+  def packet_id, do: @packet_id
+
+  @impl true
+  def packet_size, do: @packet_size
+
+  @impl true
+  def parse(
+        <<@packet_id::16-little, packet_length::16-little, gid::32-little,
+          message_data::binary-size(packet_length - @packet_size_header - 4)>>
+      ) do
+    message = message_data |> to_string() |> String.trim_trailing("\0")
+    {:ok, %__MODULE__{gid: gid, message: message}}
+  end
+
+  def parse(_), do: {:error, :invalid_packet}
+
+  @impl true
+  def build(%__MODULE__{gid: gid, message: message}) do
+    message_with_null = message <> <<0>>
+    message_length = byte_size(message_with_null)
+    packet_length = @packet_size_header + 4 + message_length
+
+    <<@packet_id::16-little, packet_length::16-little, gid::32-little, message_with_null::binary>>
+  end
+end

apps/zone_server/lib/aesir/zone_server/unit/broadcast.ex

@@ -0,0 +1,32 @@
+defmodule Aesir.ZoneServer.Unit.Broadcast do
+  @moduledoc """
+  Helper functions for broadcasting packets to entities in the zone server.
+  """
+  require Logger
+  alias Aesir.ZoneServer.Unit.UnitRegistry
+
+  @doc """
+  Broadcasts a packet to all visible players in the game state.
+
+  ## Options
+    - `exclude_id`: The entity ID to exclude from the broadcast (e.g., the sender).
+  """
+  @spec to_visible_players(map(), struct(), keyword()) :: :ok
+  def to_visible_players(game_state, packet, opts \\ []) do
+    exclude_id = Keyword.get(opts, :exclude_id)
+
+    game_state.visible_players
+    |> Enum.reject(&(&1 == exclude_id))
+    |> Enum.each(&send_to_player(&1, packet))
+  end
+
+  defp send_to_player(player_id, packet) do
+    case UnitRegistry.get_player_pid(player_id) do
+      {:ok, pid} ->
+        GenServer.cast(pid, {:send_packet, packet})
+
+      {:error, :not_found} ->
+        Logger.debug("Visible player #{player_id} not found in registry during broadcast.")
+    end
+  end
+end

apps/zone_server/lib/aesir/zone_server/unit/player/handlers/packet_handler.ex

@@ -8,15 +8,30 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
 
   alias Aesir.Commons.StatusParams
   alias Aesir.Commons.Utils.ServerTick
+  alias Aesir.ZoneServer.Packets.CzRequestChat
   alias Aesir.ZoneServer.Packets.ZcAckReqname
   alias Aesir.ZoneServer.Packets.ZcAckReqnameall
   alias Aesir.ZoneServer.Packets.ZcEquipitemList
   alias Aesir.ZoneServer.Packets.ZcLongparChange
   alias Aesir.ZoneServer.Packets.ZcNormalItemlist
+  alias Aesir.ZoneServer.Packets.ZcNotifyChat
   alias Aesir.ZoneServer.Packets.ZcNotifyTime
   alias Aesir.ZoneServer.Packets.ZcParChange
+  alias Aesir.ZoneServer.Unit.Broadcast
   alias Aesir.ZoneServer.Unit.UnitRegistry
 
+  # Chat constants
+  @chat_max_size 255
+
+  # Packet IDs
+  @cz_notify_actorinit 0x007D
+  @cz_request_time 0x007E
+  @cz_request_time2 0x0360
+  @cz_reqname2 0x0368
+  @cz_request_move 0x035F
+  @cz_request_act 0x0437
+  @cz_request_chat 0x008C
+
   @doc """
   Processes an incoming packet for a player session.
 
@@ -33,7 +48,7 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
 
   # CZ_NOTIFY_ACTORINIT - Player finished loading map
   def handle_packet(
-        0x007D,
+        @cz_notify_actorinit,
         _packet_data,
         %{character: character, connection_pid: connection_pid, game_state: game_state} = state
       ) do
@@ -75,7 +90,7 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
   end
 
   # CZ_REQUEST_TIME - Client requesting server time
-  def handle_packet(0x007E, _packet_data, %{connection_pid: connection_pid} = state) do
+  def handle_packet(@cz_request_time, _packet_data, %{connection_pid: connection_pid} = state) do
     server_tick = ServerTick.now()
 
     packet = %ZcNotifyTime{
@@ -87,7 +102,7 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
   end
 
   # CZ_REQUEST_TIME2 - Alternative client time request
-  def handle_packet(0x0360, _packet_data, %{connection_pid: connection_pid} = state) do
+  def handle_packet(@cz_request_time2, _packet_data, %{connection_pid: connection_pid} = state) do
     server_tick = ServerTick.now()
 
     packet = %ZcNotifyTime{
@@ -100,7 +115,7 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
 
   # CZ_REQNAME2 - Client requesting entity name
   def handle_packet(
-        0x0368,
+        @cz_reqname2,
         packet_data,
         %{
           character: character,
@@ -165,13 +180,13 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
   end
 
   # CZ_REQUEST_MOVE - Player movement request
-  def handle_packet(0x035F, packet_data, state) do
+  def handle_packet(@cz_request_move, packet_data, state) do
     GenServer.cast(self(), {:request_move, packet_data.dest_x, packet_data.dest_y})
     {:noreply, state}
   end
 
   # CZ_REQUEST_ACT - Player action request (attack, sit, stand, etc.)
-  def handle_packet(0x0437, packet_data, state) do
+  def handle_packet(@cz_request_act, packet_data, state) do
     case packet_data.action do
       action when action in [0, 7] ->
         # Attack actions (0 = single attack, 7 = continuous attack)
@@ -192,6 +207,48 @@ defmodule Aesir.ZoneServer.Unit.Player.Handlers.PacketHandler do
     {:noreply, state}
   end
 
+  # CZ_REQUEST_CHAT - Player sending an area chat message
+  def handle_packet(
+        @cz_request_chat,
+        %CzRequestChat{message: raw_message},
+        %{character: character, game_state: game_state, connection_pid: connection_pid} = state
+      ) do
+    # 1. Message Validation
+    # Max chat size from rAthena is 256 bytes (including null terminator)
+    if byte_size(raw_message) > @chat_max_size do
+      Logger.warning("Player #{character.id} sent a message exceeding maximum length.")
+      # Optionally send an error message to the client
+      {:noreply, state}
+    else
+      # rAthena expects "CharName : Message"
+      # We need to extract the actual message and validate the prefix
+      name_prefix = character.name <> " : "
+
+      if String.starts_with?(raw_message, name_prefix) do
+        chat_message = raw_message
+
+        # 2. Construct ZcNotifyChat packet
+        packet = %ZcNotifyChat{
+          gid: character.id,
+          message: chat_message
+        }
+
+        # 3. Broadcasting
+        # To self
+        send(connection_pid, {:send_packet, packet})
+
+        # To visible players (excluding self)
+        Broadcast.to_visible_players(game_state, packet, exclude_id: character.id)
+      else
+        Logger.warning(
+          "Player #{character.id} sent a malformed chat message (expected '#{name_prefix}'). Message: '#{raw_message}'"
+        )
+      end
+
+      {:noreply, state}
+    end
+  end
+
   # Fallback for unknown packets
   def handle_packet(packet_id, _packet_data, state) do
     Logger.warning("Unhandled packet in PacketHandler: 0x#{Integer.to_string(packet_id, 16)}")