# MainMenu.swf — Multiplayer button patch guide

> **Full FFDec walkthrough:** see [`FFDEC_MainMenu_Multiplayer_Guide.md`](FFDEC_MainMenu_Multiplayer_Guide.md) for exact search anchors, before/after snippets, and a test checklist.

Add a **Multiplayer** item to the title-screen main menu. Selecting it calls `root.f4se.plugins.commonwealthOnline.openManager()`, which opens the PrismaUI server browser (same as **F9**).

## CRITICAL — edit methods, not the whole script

**Never** paste the full exported `MainMenu.as` into FFDec or use **Import script** on the whole class. That recompiles `RequestOptions` from decompiled source and **breaks Settings → Gameplay / Display / Audio**.

In FFDec, edit **individual methods** (double-click the method under **MainMenu** traits). FFDec then recompiles only that method and leaves vanilla bytecode (including `RequestOptions`) intact.

Restore vanilla any time:

```powershell
.\tools\restore-vanilla-mainmenu.ps1
```

## Prerequisites

- [JPEXS FFDec](https://github.com/jindrapetrik/jpexs-decompiler/releases)
- Game launched via **F4SE** with `CommonwealthOnline.dll` installed
- Loose Interface overrides enabled in `Fallout4Custom.ini`:

```ini
[Archive]
bInvalidateOlderFiles=1
```

## FFDec workflow

1. Copy `Interface/MainMenu.swf.vanilla.bak` → `Interface/MainMenu.swf` (start from vanilla every time).
2. Open `Interface/MainMenu.swf` in FFDec.
3. In the left tree: **scripts → MainMenu** (class traits list, not “Edit ActionScript” on the whole class).
4. Apply the **four method-level edits** below (double-click each method to open its editor, save after each).
5. **File → Save**.
6. Sanity check: patched SWF should stay **~62–63 KB**. If it jumps to **64 KB+**, settings are likely broken — restore vanilla and retry using **method** editors only.
7. Copy to `Fallout 4/Data/Interface/MainMenu.swf`.
8. Test **Settings → Gameplay / Display / Audio** first, then **Multiplayer**.

---

## Edit 1 — Add constant (class body)

Open the **MainMenu** class initializer / constants section (or edit at top of class in trait view). After `INSTALLED_CONTENT_INDEX`:

```actionscript
private const MULTIPLAYER_INDEX:Number = 15;
```

Index `15` is unused in vanilla (highest is `INSTALLED_CONTENT_INDEX = 14`).

---

## Edit 2 — `InitList()` — add menu row

In **`InitList`**, find the `$LOAD` push (after `$NEW` on title screen). Insert **before** the PS5 transfer block:

```actionscript
         this.MainPanel_mc.List_mc.entryList.push({
            "text":"$LOAD",
            "disabled":!this.HasRecentSave || !param6,
            "index":this.LOAD_INDEX
         });
         if(!this.PauseMode)
         {
            this.MainPanel_mc.List_mc.entryList.push({
               "text":"Multiplayer",
               "index":this.MULTIPLAYER_INDEX
            });
         }
         if(param8 == true)
```

Use literal `"Multiplayer"` (no `$` prefix) unless you add a row to `Interface/Translate_en.txt`.

---

## Edit 3 — `onMainListItemPress()` — handle click

In the main `switch(this.MainPanel_mc.List_mc.selectedEntry.index)`, add **before** `case this.HELP_INDEX:`:

```actionscript
               case this.MULTIPLAYER_INDEX:
                  this.BGSCodeObj.PlayOKSound();
                  if(root.f4se != null && root.f4se.plugins != null && root.f4se.plugins.commonwealthOnline != null)
                  {
                     root.f4se.plugins.commonwealthOnline.openManager();
                  }
                  break;
```

---

## Edit 4 (recommended) — auto-close browser

The plugin also hides the browser when the menu leaves `MAIN_STATE`, but these SWF hooks close it immediately when navigating away.

### 4a — Add new method `CloseMultiplayerBrowser`

In FFDec: **MainMenu → right-click → Add script** / add method:

```actionscript
      private function CloseMultiplayerBrowser() : *
      {
         if(root.f4se != null && root.f4se.plugins != null && root.f4se.plugins.commonwealthOnline != null)
         {
            root.f4se.plugins.commonwealthOnline.closeManager();
         }
      }
```

### 4b — Edit `set currentState`

After `this.strCurrentState = param1;`:

```actionscript
         this.strCurrentState = param1;
         if(param1 != this.MAIN_STATE)
         {
            this.CloseMultiplayerBrowser();
         }
         this.UpdateButtons(param1);
```

### 4c — Edit `onMainListItemPress`

After the `while(this.strCurrentState != this.MAIN_STATE)` loop, before the `switch`:

```actionscript
            if(this.MainPanel_mc.List_mc.selectedEntry.index != this.MULTIPLAYER_INDEX)
            {
               this.CloseMultiplayerBrowser();
            }
```

---

## Test plan

| Step | Expected |
|------|----------|
| Main menu shows **Multiplayer** between Load and Add-ons | Yes |
| Click **Multiplayer** | Server browser opens |
| Open **Settings → Display** | No crash |
| Open **Settings → Gameplay / Audio** | No crash |
| Select **Continue** while browser open | Browser closes |
| **F9** | Still toggles browser |

---

## Reference

Full decompiled class (do **not** import wholesale): [`scripts/MainMenu.as`](scripts/MainMenu.as)

Plugin API registered in `CommonwealthOnline.dll`:

- `root.f4se.plugins.commonwealthOnline.openManager()`
- `root.f4se.plugins.commonwealthOnline.closeManager()`