implement 6xCB subcommand

src/Client.hh

@@ -54,6 +54,7 @@ struct Client : public std::enable_shared_from_this<Client> {
     HAS_EP3_MEDIA_UPDATES               = 0x0000000010000000,
     USE_OVERRIDE_RANDOM_SEED            = 0x0000000020000000,
     HAS_GUILD_CARD_NUMBER               = 0x0000000040000000,
+    AT_BANK_COUNTER                     = 0x0000000080000000,
 
     // Cheat mode flags
     SWITCH_ASSIST_ENABLED               = 0x0000000100000000,

src/CommandFormats.hh

@@ -3356,8 +3356,9 @@ struct S_TeamInfoForPlayer_BB_13EA_15EA_Entry {
 // header.flag specifies the number of entries. The entry format appears to be
 // the same as for the 13EA command.
 
-// 16EA (S->C): Unknown
-// No arguments except header.flag.
+// 16EA (S->C): Transfer item via Simple Mail result
+// No arguments except header.flag, which is 0 if the transfer failed and
+// nonzero if it succeeded.
 
 // 18EA: Intra-team ranking information
 // No arguments (C->S)
@@ -5486,7 +5487,7 @@ struct G_BankAction_BB_6xBD {
   G_UnusedHeader header;
   le_uint32_t item_id = 0; // 0xFFFFFFFF = meseta; anything else = item
   le_uint32_t meseta_amount = 0;
-  uint8_t action = 0; // 0 = deposit, 1 = take
+  uint8_t action = 0; // 0 = deposit, 1 = take, 3 = done (close bank window)
   uint8_t item_amount = 0;
   le_uint16_t unused2 = 0;
 } __packed__;
@@ -5608,13 +5609,13 @@ struct G_ItemRewardRequest_BB_6xCA {
   ItemData item_data;
 } __packed__;
 
-// 6xCB: Request to transfer item (BB)
+// 6xCB: Transfer item via mail message (BB)
 
-struct G_ItemTransferRequest_BB_6xCB {
+struct G_TransferItemViaMailMessage_BB_6xCB {
   G_ClientIDHeader header;
-  le_uint32_t unknown_a1 = 0;
-  le_uint32_t unknown_a2 = 0;
-  le_uint32_t unknown_a3 = 0;
+  le_uint32_t item_id = 0;
+  le_uint32_t amount = 0;
+  le_uint32_t target_guild_card_number = 0;
 } __packed__;
 
 // 6xCC: Exchange item for team points (BB)

src/PlayerSubordinates.cc

@@ -466,17 +466,18 @@ void PlayerBank::add_item(const ItemData& item) {
     }
 
     if (y < this->num_items) {
-      this->items[y].data.data1[5] += item.data1[5];
-      if (this->items[y].data.data1[5] > combine_max) {
-        this->items[y].data.data1[5] = combine_max;
+      uint8_t new_count = this->items[y].data.data1[5] + item.data1[5];
+      if (new_count > combine_max) {
+        throw runtime_error("stack size would exceed limit");
       }
-      this->items[y].amount = this->items[y].data.data1[5];
+      this->items[y].data.data1[5] = new_count;
+      this->items[y].amount = new_count;
       return;
     }
   }
 
   if (this->num_items >= 200) {
-    throw runtime_error("bank is full");
+    throw runtime_error("no free space in bank");
   }
   auto& last_item = this->items[this->num_items];
   last_item.data = item;

src/ReceiveSubcommands.cc

@@ -1428,6 +1428,7 @@ static void on_open_shop_bb_or_ep3_battle_subs(shared_ptr<Client> c, uint8_t com
 static void on_open_bank_bb_or_card_trade_counter_ep3(shared_ptr<Client> c, uint8_t command, uint8_t flag, const void* data, size_t size) {
   auto l = c->require_lobby();
   if ((l->base_version == Version::BB_V4) && l->is_game()) {
+    c->config.set_flag(Client::Flag::AT_BANK_COUNTER);
     send_bank(c);
   } else if (l->is_ep3()) {
     forward_subcommand(c, command, flag, data, size);
@@ -1501,6 +1502,9 @@ static void on_ep3_private_word_select_bb_bank_action(shared_ptr<Client> c, uint
             c->lobby_client_id, cmd.item_id.load(), cmd.item_amount, name.c_str());
         c->game_data.character()->print_inventory(stderr, c->version(), s->item_name_index);
       }
+
+    } else if (cmd.action == 3) { // Leave bank counter
+      c->config.clear_flag(Client::Flag::AT_BANK_COUNTER);
     }
 
   } else if (is_ep3(c->version())) {
@@ -2110,6 +2114,71 @@ void on_item_reward_request_bb(shared_ptr<Client> c, uint8_t, uint8_t, const voi
   send_create_inventory_item(c, item);
 }
 
+void on_transfer_item_via_mail_message_bb(shared_ptr<Client> c, uint8_t command, uint8_t flag, const void* data, size_t size) {
+  const auto& cmd = check_size_t<G_TransferItemViaMailMessage_BB_6xCB>(data, size);
+
+  auto team = c->team();
+  if (!team) {
+    throw runtime_error("player is not in a team");
+  }
+  auto l = c->require_lobby();
+  if (!l->is_game()) {
+    return;
+  }
+  if (cmd.header.client_id != c->lobby_client_id) {
+    return;
+  }
+
+  if (l->base_version != Version::BB_V4) {
+    throw runtime_error("item tracking not enabled in BB game");
+  }
+  if (!l->check_flag(Lobby::Flag::ITEM_TRACKING_ENABLED)) {
+    throw runtime_error("item tracking not enabled in BB game");
+  }
+
+  forward_subcommand(c, command, flag, data, size);
+
+  auto s = c->require_server_state();
+  auto p = c->game_data.character();
+  auto item = p->remove_item(cmd.item_id, cmd.amount, c->version() != Version::BB_V4);
+
+  auto name = s->describe_item(c->version(), item, false);
+  l->log.info("Player %hhu sent inventory item %hu:%08" PRIX32 " (%s) x%" PRIu32 " to player %08" PRIX32,
+      c->lobby_client_id, cmd.header.client_id.load(), cmd.item_id.load(), name.c_str(), cmd.amount.load(), cmd.target_guild_card_number.load());
+  if (c->config.check_flag(Client::Flag::DEBUG_ENABLED)) {
+    string name = s->describe_item(c->version(), item, true);
+    send_text_message_printf(c, "$C5SEND/MAIL %08" PRIX32 " x%" PRIu32 "\n%s", cmd.item_id.load(), cmd.amount.load(), name.c_str());
+  }
+  p->print_inventory(stderr, c->version(), s->item_name_index);
+
+  // To receive an item, the player must be online, using BB, have a character
+  // loaded (that is, be in a lobby or game), not be at the bank counter at the
+  // moment, and there must be room in their bank to receive the item.
+  bool item_sent = false;
+  auto target_c = s->find_client(nullptr, cmd.target_guild_card_number);
+  if (target_c &&
+      (target_c->version() == Version::BB_V4) &&
+      (target_c->game_data.character(false) != nullptr) &&
+      !target_c->config.check_flag(Client::Flag::AT_BANK_COUNTER)) {
+    auto target_p = target_c->game_data.character(false);
+    try {
+      target_p->bank.add_item(item);
+      item_sent = true;
+    } catch (const runtime_error&) {
+    }
+  }
+
+  if (item_sent) {
+    send_command(c, 0x16EA, 0x00000001);
+  } else {
+    send_command(c, 0x16EA, 0x00000000);
+    // If the item failed to send, add it back to the sender's inventory
+    item.id = l->generate_item_id(0xFF);
+    p->add_item(item);
+    send_create_inventory_item(c, item);
+  }
+}
+
 void on_exchange_item_for_team_points_bb(shared_ptr<Client> c, uint8_t command, uint8_t flag, const void* data, size_t size) {
   const auto& cmd = check_size_t<G_ExchangeItemForTeamPoints_BB_6xCC>(data, size);
 
@@ -2926,7 +2995,7 @@ SubcommandDefinition subcommand_definitions[0x100] = {
     /* 6xC8 */ {0x00, 0x00, 0xC8, on_enemy_exp_request_bb},
     /* 6xC9 */ {0x00, 0x00, 0xC9, on_meseta_reward_request_bb},
     /* 6xCA */ {0x00, 0x00, 0xCA, on_item_reward_request_bb},
-    /* 6xCB */ {0x00, 0x00, 0xCB, nullptr},
+    /* 6xCB */ {0x00, 0x00, 0xCB, on_transfer_item_via_mail_message_bb},
     /* 6xCC */ {0x00, 0x00, 0xCC, on_exchange_item_for_team_points_bb},
     /* 6xCD */ {0x00, 0x00, 0xCD, on_forward_check_size},
     /* 6xCE */ {0x00, 0x00, 0xCE, on_forward_check_size},