implement 6xD1 command for BB challenge mode

src/CommandFormats.hh

@@ -5629,15 +5629,15 @@ struct G_BattleModeLevelUp_BB_6xD0 {
   le_uint32_t num_levels = 0;
 } __packed__;
 
-// 6xD1: Challenge mode grave (BB; handled by server)
+// 6xD1: Request Challenge Mode grave recovery item (BB; handled by server)
 
-struct G_ChallengeModeGrave_BB_6xD1 {
+struct G_ChallengeModeGraveRecoveryItemRequest_BB_6xD1 {
   G_ClientIDHeader header;
-  le_uint16_t unknown_a1 = 0;
+  le_uint16_t floor = 0;
   le_uint16_t unknown_a2 = 0;
-  le_uint32_t unknown_a3 = 0;
-  le_uint32_t unknown_a4 = 0;
-  le_uint32_t unknown_a5 = 0;
+  le_float x = 0;
+  le_float z = 0;
+  le_uint32_t item_type = 0; // Should be < 6
 } __packed__;
 
 // 6xD2: Set quest global flag (BB)

src/ItemData.cc

@@ -18,6 +18,12 @@ ItemData::ItemData(const ItemData& other) {
   this->data2d = other.data2d;
 }
 
+ItemData::ItemData(uint64_t first, uint64_t second) {
+  *reinterpret_cast<be_uint64_t*>(&this->data1[0]) = first;
+  this->data1d[2] = bswap32((second >> 32) & 0xFFFFFFFF);
+  this->data2d = bswap32(second & 0xFFFFFFFF);
+}
+
 ItemData& ItemData::operator=(const ItemData& other) {
   this->data1d = other.data1d;
   this->id = other.id;

src/ItemData.hh

@@ -122,6 +122,7 @@ struct ItemData { // 0x14 bytes
 
   ItemData();
   ItemData(const ItemData& other);
+  ItemData(uint64_t first, uint64_t second = 0);
   ItemData& operator=(const ItemData& other);
 
   bool operator==(const ItemData& other) const;

src/ReceiveSubcommands.cc

@@ -2302,6 +2302,28 @@ static void on_battle_level_up_bb(shared_ptr<Client> c, uint8_t, uint8_t, const
   }
 }
 
+static void on_request_challenge_grave_recovery_item_bb(shared_ptr<Client> c, uint8_t, uint8_t, const void* data, size_t size) {
+  auto l = c->require_lobby();
+  if (l->is_game() &&
+      (l->base_version == GameVersion::BB) &&
+      (l->mode == GameMode::CHALLENGE) &&
+      l->check_flag(Lobby::Flag::QUEST_IN_PROGRESS)) {
+    const auto& cmd = check_size_t<G_ChallengeModeGraveRecoveryItemRequest_BB_6xD1>(data, size);
+    static const array<ItemData, 6> items = {
+        ItemData(0x0300000000010000), // Monomate x1
+        ItemData(0x0300010000010000), // Dimate x1
+        ItemData(0x0300020000010000), // Trimate x1
+        ItemData(0x0301000000010000), // Monofluid x1
+        ItemData(0x0301010000010000), // Difluid x1
+        ItemData(0x0301020000010000), // Trifluid x1
+    };
+    ItemData item = items.at(cmd.item_type);
+    item.id = l->generate_item_id(0xFF);
+    l->add_item(item, cmd.floor, cmd.x, cmd.z);
+    send_drop_stacked_item(l, item, cmd.floor, cmd.x, cmd.z);
+  }
+}
+
 static void on_quest_exchange_item_bb(shared_ptr<Client> c, uint8_t, uint8_t, const void* data, size_t size) {
   auto l = c->require_lobby();
   if (l->is_game() &&
@@ -2875,7 +2897,7 @@ subcommand_handler_t subcommand_handlers[0x100] = {
     /* 6xCE */ nullptr,
     /* 6xCF */ on_battle_restart_bb,
     /* 6xD0 */ on_battle_level_up_bb,
-    /* 6xD1 */ nullptr,
+    /* 6xD1 */ on_request_challenge_grave_recovery_item_bb,
     /* 6xD2 */ on_write_quest_global_flag_bb,
     /* 6xD3 */ nullptr,
     /* 6xD4 */ nullptr,

src/SendCommands.hh

@@ -296,10 +296,8 @@ void send_drop_item(std::shared_ptr<ServerState> s, Channel& ch, const ItemData&
     bool from_enemy, uint8_t floor, float x, float z, uint16_t request_id);
 void send_drop_item(std::shared_ptr<Lobby> l, const ItemData& item,
     bool from_enemy, uint8_t floor, float x, float z, uint16_t request_id);
-void send_drop_stacked_item(std::shared_ptr<ServerState> s, Channel& ch, const ItemData& item,
-    uint8_t floor, float x, float z);
-void send_drop_stacked_item(std::shared_ptr<Lobby> l, const ItemData& item,
-    uint8_t floor, float x, float z);
+void send_drop_stacked_item(std::shared_ptr<ServerState> s, Channel& ch, const ItemData& item, uint8_t floor, float x, float z);
+void send_drop_stacked_item(std::shared_ptr<Lobby> l, const ItemData& item, uint8_t floor, float x, float z);
 void send_pick_up_item(std::shared_ptr<Client> c, uint32_t id, uint8_t floor);
 void send_create_inventory_item(std::shared_ptr<Client> c, const ItemData& item);
 void send_destroy_item(std::shared_ptr<Client> c, uint32_t item_id, uint32_t amount);