[Enhancement] Keep Express Mail in the same cycle (#791)

* Add enhancement for reusing letter to mama in one cycle

* add menu widget item for express mail

mm/2s2h/BenGui/BenMenuBar.cpp

@@ -476,6 +476,13 @@ void DrawEnhancementsMenu() {
                 { .tooltip =
                       "Playing the Song Of Time will not reset the current time speed set by Inverted Song of Time." });
 
+            if (UIWidgets::CVarCheckbox(
+                    "Keep Express Mail", "gEnhancements.Cycle.KeepExpressMail",
+                    { .tooltip = "Allows the player to keep the Express Mail in their inventory after delivering it "
+                                 "the first time, so that both deliveries can be done within one cycle" })) {
+                RegisterKeepExpressMail();
+            }
+
             ImGui::PushStyleColor(ImGuiCol_Text, ImVec4(255, 255, 0, 255));
             ImGui::SeparatorText("Unstable");
             ImGui::PopStyleColor();

mm/2s2h/BenGui/SearchableMenuItems.h

@@ -930,6 +930,17 @@ void AddEnhancements() {
                 "Playing the Song Of Time will not reset the Sword back to Kokiri Sword.", WIDGET_CVAR_CHECKBOX },
               { "Do not reset Rupees", "gEnhancements.Cycle.DoNotResetRupees",
                 "Playing the Song Of Time will not reset the your rupees.", WIDGET_CVAR_CHECKBOX },
+              { "Do not reset Time Speed", "gEnhancements.Cycle.DoNotResetTimeSpeed",
+                "Playing the Song Of Time will not reset the current time speed set by Inverted Song of Time.",
+                WIDGET_CVAR_CHECKBOX },
+              {
+                  .widgetName = "Keep Express Mail",
+                  .widgetCVar = "gEnhancements.Cycle.KeepExpressMail",
+                  .widgetTooltip = "Allows the player to keep the Express Mail in their inventory after delivering it "
+                                   "the first time, so that both deliveries can be done within one cycle",
+                  .widgetType = WIDGET_CVAR_CHECKBOX,
+                  .widgetCallback = [](widgetInfo& info) { RegisterKeepExpressMail(); },
+              },
               { .widgetName = "Unstable",
                 .widgetType = WIDGET_SEPARATOR_TEXT,
                 .widgetOptions = { .color = UIWidgets::Colors::Yellow } },

mm/2s2h/Enhancements/Cycle/Cycle.h

@@ -2,5 +2,6 @@
 #define CYCLE_H
 
 void RegisterEndOfCycleSaveHooks();
+void RegisterKeepExpressMail();
 
 #endif // CYCLE_H

mm/2s2h/Enhancements/Cycle/KeepExpressMail.cpp

@@ -0,0 +1,55 @@
+#include "libultraship/bridge.h"
+#include "2s2h/GameInteractor/GameInteractor.h"
+
+extern "C" {
+#include "z64save.h"
+#include "z64scene.h"
+#include "variables.h"
+}
+
+static HOOK_ID onItemDeleteID = 0;
+
+void CheckScene(s16 sceneId) {
+    if (sceneId != SCENE_MILK_BAR && sceneId != SCENE_POSTHOUSE) {
+        return;
+    }
+
+    onItemDeleteID = REGISTER_VB_SHOULD(VB_MSG_SCRIPT_DEL_ITEM, {
+        Actor* actor = va_arg(args, Actor*);
+        ItemId itemId = va_arg(args, ItemId);
+
+        // Keep the express mail only on the first trade for the cycle
+        // Postman checking for Madame Aroma trade cycle flag
+        // Madame Aroma checking for Postman trade cycle flag
+        if (itemId == ITEM_LETTER_MAMA && (actor->id == ACTOR_EN_PM && !CHECK_WEEKEVENTREG(WEEKEVENTREG_57_04)) ||
+            (actor->id == ACTOR_EN_AL && !CHECK_WEEKEVENTREG(WEEKEVENTREG_86_01))) {
+            *should = false;
+        }
+    });
+}
+
+void RegisterKeepExpressMail() {
+    static HOOK_ID onSceneInitID = 0;
+
+    GameInteractor::Instance->UnregisterGameHookForID<GameInteractor::ShouldVanillaBehavior>(onItemDeleteID);
+    GameInteractor::Instance->UnregisterGameHook<GameInteractor::OnSceneInit>(onSceneInitID);
+    onSceneInitID = 0;
+    onItemDeleteID = 0;
+
+    if (!CVarGetInteger("gEnhancements.Cycle.KeepExpressMail", 0)) {
+        return;
+    }
+
+    // Register item hook right away after toggle
+    if (gPlayState != nullptr) {
+        CheckScene(gPlayState->sceneId);
+    }
+
+    onSceneInitID =
+        GameInteractor::Instance->RegisterGameHook<GameInteractor::OnSceneInit>([](s16 sceneId, s8 spawnNum) {
+            GameInteractor::Instance->UnregisterGameHookForID<GameInteractor::ShouldVanillaBehavior>(onItemDeleteID);
+            onItemDeleteID = 0;
+
+            CheckScene(sceneId);
+        });
+}

mm/2s2h/Enhancements/Enhancements.cpp

@@ -22,6 +22,7 @@ void InitEnhancements() {
     RegisterEndOfCycleSaveHooks();
     RegisterSavingEnhancements();
     RegisterAutosave();
+    RegisterKeepExpressMail();
 
     // Dialogue
     RegisterFastBankSelection();

mm/2s2h/GameInteractor/GameInteractor.h

@@ -48,6 +48,7 @@ typedef enum {
     VB_SONG_AVAILABLE_TO_PLAY,
     VB_USE_CUSTOM_CAMERA,
     VB_DELETE_OWL_SAVE,
+    VB_MSG_SCRIPT_DEL_ITEM,
     VB_CONSIDER_BUNNY_HOOD_EQUIPPED,
     VB_USE_ITEM_EQUIP_MASK,
     VB_KALEIDO_DISPLAY_ITEM_TEXT,

mm/src/code/z_msgevent.c

@@ -1,5 +1,7 @@
 #include "global.h"
 
+#include "2s2h/GameInteractor/GameInteractor.h"
+
 #define MSCRIPT_CONTINUE 0
 #define MSCRIPT_STOP 1
 
@@ -876,6 +878,10 @@ s32 MsgEvent_Cmd42(Actor* actor, PlayState* play, u8** scriptPtr, MsgEventCallba
     u8* script = *scriptPtr;
     s16 item = MSCRIPT_GET_16(script, 1);
 
+    if (!GameInteractor_Should(VB_MSG_SCRIPT_DEL_ITEM, true, actor, item)) {
+        return MSCRIPT_CONTINUE;
+    }
+
     Inventory_DeleteItem(item, SLOT(item));
     return MSCRIPT_CONTINUE;
 }