From d7519b540e24df073a9cafdc32af73f125b5a175 Mon Sep 17 00:00:00 2001
From: cawtds <dennis.stamm@gmx.de>
Date: Sat, 1 Jun 2024 21:12:29 +0200
Subject: [PATCH] dynamax candy functionality

---
 data/maps/ViridianCity_Mart/scripts.inc |  1 +
 include/item_use.h                      |  1 +
 include/party_menu.h                    |  3 +-
 src/data/items.h                        |  2 +-
 src/item_use.c                          |  6 +++
 src/party_menu.c                        | 64 +++++++++++++++++++++++++
 6 files changed, 74 insertions(+), 3 deletions(-)

diff --git a/data/maps/ViridianCity_Mart/scripts.inc b/data/maps/ViridianCity_Mart/scripts.inc
index 28438446e..7817f2246 100644
--- a/data/maps/ViridianCity_Mart/scripts.inc
+++ b/data/maps/ViridianCity_Mart/scripts.inc
@@ -131,6 +131,7 @@ ViridianCity_Mart_Items::
 	.2byte ITEM_BOLD_MINT
 	.2byte ITEM_ADAMANT_MINT
 	.2byte ITEM_SERIOUS_MINT
+	.2byte ITEM_DYNAMAX_CANDY
 	.2byte ITEM_NONE
 	release
 	end
diff --git a/include/item_use.h b/include/item_use.h
index 3a8990195..5b0d4f69d 100644
--- a/include/item_use.h
+++ b/include/item_use.h
@@ -13,6 +13,7 @@ void ItemUseOutOfBattle_BerryPouch(u8 taskId);
 void ItemUseOutOfBattle_Bike(u8 taskId);
 void ItemUseOutOfBattle_BlackWhiteFlute(u8 taskId);
 void ItemUseOutOfBattle_CoinCase(u8 taskId);
+void ItemUseOutOfBattle_DynamaxCandy(u8);
 void ItemUseOutOfBattle_EscapeRope(u8 taskId);
 void ItemUseOutOfBattle_EnigmaBerry(u8 taskId);
 void ItemUseOutOfBattle_EvolutionStone(u8 taskId);
diff --git a/include/party_menu.h b/include/party_menu.h
index cd199b855..062617409 100644
--- a/include/party_menu.h
+++ b/include/party_menu.h
@@ -65,6 +65,7 @@ bool8 MonKnowsMove(struct Pokemon *mon, u16 move);
 bool8 BoxMonKnowsMove(struct BoxPokemon *boxMon, u16 move);
 void ItemUseCB_TMHM(u8 taskId, TaskFunc func);
 void ItemUseCB_RareCandy(u8 taskId, TaskFunc func);
+void ItemUseCB_DynamaxCandy(u8 taskId, TaskFunc task);
 void ItemUseCB_SacredAsh(u8 taskId, TaskFunc func);
 void ItemUseCB_EvolutionStone(u8 taskId, TaskFunc func);
 u8 GetItemEffectType(u16 item);
@@ -88,8 +89,6 @@ u8 GetPartyIdFromBattlePartyId(u8 battlePartyId);
 void ShowPartyMenuToShowcaseMultiBattleParty(void);
 void ChooseMonForDaycare(void);
 void ChoosePartyMonByMenuType(u8 menuType);
-
-// pokeemerald
 void ItemUseCB_BattleChooseMove(u8 taskId, TaskFunc task);
 const u8* GetItemEffect(u16 item);
 
diff --git a/src/data/items.h b/src/data/items.h
index caeff0a2e..87a2a90f1 100644
--- a/src/data/items.h
+++ b/src/data/items.h
@@ -1806,7 +1806,7 @@ const struct Item gItemsInfo[] =
             "Pokémon by one."),
         .pocket = POCKET_ITEMS,
         .type = ITEM_TYPE_PARTY_MENU,
-        .fieldUseFunc = ItemUseOutOfBattle_CannotUse,
+        .fieldUseFunc = ItemUseOutOfBattle_DynamaxCandy,
         .flingPower = 30,
     },
 
diff --git a/src/item_use.c b/src/item_use.c
index 9b41db7ff..dafac5a63 100644
--- a/src/item_use.c
+++ b/src/item_use.c
@@ -301,6 +301,12 @@ void ItemUseOutOfBattle_CoinCase(u8 taskId)
         DisplayItemMessageOnField(taskId, FONT_NORMAL, gStringVar4, Task_ItemUse_CloseMessageBoxAndReturnToField);
 }
 
+void ItemUseOutOfBattle_DynamaxCandy(u8 taskId)
+{
+    gItemUseCB = ItemUseCB_DynamaxCandy;
+    SetUpItemUseCallback(taskId);
+}
+
 void ItemUseOutOfBattle_PowderJar(u8 taskId)
 {
     ConvertIntToDecimalStringN(gStringVar1, GetBerryPowder(), STR_CONV_MODE_LEFT_ALIGN, 5);
diff --git a/src/party_menu.c b/src/party_menu.c
index b19bea22f..5ac51fbaf 100644
--- a/src/party_menu.c
+++ b/src/party_menu.c
@@ -5751,6 +5751,70 @@ static void DisplayMonLearnedMove(u8 taskId, u16 move)
 #define tHadEffect    data[1]
 #define tLastSlotUsed data[2]
 
+#define tState        data[0]
+#define tMonId        data[1]
+#define tDynamaxLevel data[2]
+#define tOldFunc      4
+
+void Task_DynamaxCandy(u8 taskId)
+{
+    static const u8 doneText[] = _("{STR_VAR_1}'s Dynamax Level\nincreased by 1!{PAUSE_UNTIL_PRESS}");
+    s16 *data = gTasks[taskId].data;
+
+    switch (tState)
+    {
+    case 0:
+        // Can't use.
+        if (tDynamaxLevel == MAX_DYNAMAX_LEVEL)
+        {
+            gPartyMenuUseExitCallback = FALSE;
+            PlaySE(SE_SELECT);
+            DisplayPartyMenuMessage(gText_WontHaveEffect, 1);
+            ScheduleBgCopyTilemapToVram(2);
+            gTasks[taskId].func = Task_ClosePartyMenuAfterText;
+            return;
+        }
+        gPartyMenuUseExitCallback = TRUE;
+        GetMonNickname(&gPlayerParty[tMonId], gStringVar1);
+        CopyItemName(gSpecialVar_ItemId, gStringVar2);
+        tState++;
+        break;
+    case 1:
+        PlaySE(SE_USE_ITEM);
+        StringExpandPlaceholders(gStringVar4, doneText);
+        DisplayPartyMenuMessage(gStringVar4, 1);
+        ScheduleBgCopyTilemapToVram(2);
+        tState++;
+        break;
+    case 2:
+        if (!IsPartyMenuTextPrinterActive())
+            tState++;
+        break;
+    case 3:
+        tDynamaxLevel++;
+        SetMonData(&gPlayerParty[tMonId], MON_DATA_DYNAMAX_LEVEL, &tDynamaxLevel);
+        RemoveBagItem(gSpecialVar_ItemId, 1);
+        gTasks[taskId].func = Task_ClosePartyMenu;
+        break;
+    }
+}
+
+void ItemUseCB_DynamaxCandy(u8 taskId, TaskFunc task)
+{
+    s16 *data = gTasks[taskId].data;
+
+    tState = 0;
+    tMonId = gPartyMenu.slotId;
+    tDynamaxLevel = GetMonData(&gPlayerParty[tMonId], MON_DATA_DYNAMAX_LEVEL);
+    SetWordTaskArg(taskId, tOldFunc, (uintptr_t)(gTasks[taskId].func));
+    gTasks[taskId].func = Task_DynamaxCandy;
+}
+
+#undef tState
+#undef tMonId
+#undef tDynamaxLevel
+#undef tOldFunc
+
 void ItemUseCB_SacredAsh(u8 taskId, TaskFunc func)
 {
     sPartyMenuInternal->tUsedOnSlot = FALSE;