Fix SWELL drag guard, channel-fork the VST editor window class, dedupe own-module match

Panel drag no longer misfires on SWELL's always-zero wParam; stable/beta VST editors register distinct window classes against their own module instead of colliding on REAPER's; own-module basename matching moves to a tested pure helper.

src/shell/actions/drag_out_win.cpp

@@ -326,25 +326,9 @@ std::string moduleFileName(HMODULE mod) {
     }
 }
 
-// True iff `path`'s file name (the part after the last separator) case-insensitively matches
-// `fileName` — Windows paths are case-insensitive, and GetModuleFileName's casing tracks however
-// the module was loaded (often not the on-disk casing).
-bool sameBaseName(const std::string& path, const std::string& fileName) {
-    const std::size_t pos = path.find_last_of("\\/");
-    const std::string base = pos == std::string::npos ? path : path.substr(pos + 1);
-    if (base.size() != fileName.size()) return false;
-    for (std::size_t i = 0; i < base.size(); ++i) {
-        char a = base[i], b = fileName[i];
-        if (a >= 'A' && a <= 'Z') a = static_cast<char>(a - 'A' + 'a');
-        if (b >= 'A' && b <= 'Z') b = static_cast<char>(b - 'A' + 'a');
-        if (a != b) return false;
-    }
-    return true;
-}
-
 // This channel's own ReaSampler 9000 module file name (e.g. "reasampler_9000.vst3", or the
-// "_beta" variant) — the same name CMake gives the built .vst3 (OUTPUT_NAME + SUFFIX), so stable
-// and beta each recognise only their own binary, never the other channel's.
+// "_beta" variant) — the same name CMake gives the built .vst3 (OUTPUT_NAME + SUFFIX). Matching
+// logic lives in core/ui/window_origin's isOwnModulePath; see there.
 const std::string& ownVstFileName() {
     static const std::string name = version::vstOutputName() + ".vst3";
     return name;
@@ -385,7 +369,7 @@ ui::WindowFacts windowFacts(HWND hwnd) {
     // (string-building) lookup in that case.
     if (!f.hostModule) {
         f.modulePath = moduleFileName(mod);
-        f.ownModule = sameBaseName(f.modulePath, ownVstFileName());
+        f.ownModule = ui::isOwnModulePath(f.modulePath, ownVstFileName());
     }
     return f;
 }

src/shell/actions/drag_out_win.h

@@ -68,9 +68,13 @@ bool pointerOverHostWindow(int screenX, int screenY);
 //   - an all-#32770 dialog-based editor (the generic Windows dialog class) resolves to no
 //     recognizable plugin module — falls to REAPER's outcome;
 //   - a .NET/WPF editor's class procedure is a CLR-thunked address with no resolvable module —
-//     also falls to REAPER's outcome;
+//     also falls to REAPER's outcome; `[verify]`;
 //   - our own ReaSampler 9000 module (this channel's reasampler_9000[_beta].vst3, matched by
-//     basename) also falls to REAPER's outcome, deliberately — see ui::WindowFacts::ownModule.
+//     basename) also falls to REAPER's outcome, deliberately — see ui::WindowFacts::ownModule;
+//   - ReaSampler 9000 itself run bridged/in a separate process reads as Plugin, same as any other
+//     bridged plugin — banner (the OS hand-off fires over our own editor), harmless;
+//   - a renamed ReaSampler 9000 binary (the basename no longer matches ownVstFileName()) misses
+//     the exemption and reads as Plugin — banner, harmless.
 // The opposite direction is unguarded: a third-party hook that replaces REAPER's own chrome
 // class procedure via SetClassLongPtr(GCLP_WNDPROC) would make REAPER's own window read as
 // Plugin — toward OLE instead of away from it.

src/shell/instrument/editor_platform.cpp

@@ -13,6 +13,7 @@
 
 #include "shell/instrument/editor_internal.h"  // (transitively: lice + the kit, Windows only)
 #include "shell/instrument/reasampler_processor.h"
+#include "core/version/app_version.h"  // vstOutputName — channel-forked window class name
 
 using namespace Steinberg;
 
@@ -20,7 +21,32 @@ namespace reasampler::vst {
 
 #ifdef _WIN32
 namespace {
-constexpr const wchar_t* kChildClassName = L"ReaSampler9000VstEditor";
+
+// Channel-forked so stable and beta never fight over one class registration (a second
+// RegisterClassW against an already-taken name silently fails, leaving that channel's editors
+// running the FIRST-registered channel's wndProc). vstOutputName() is ASCII (CMake OUTPUT_NAME),
+// so a plain widen is safe.
+const std::wstring& childClassName() {
+    static const std::wstring name = [] {
+        const std::string& base = version::vstOutputName();
+        return std::wstring(base.begin(), base.end()) + L"VstEditor";
+    }();
+    return name;
+}
+
+// The module holding a given code address — used to resolve THIS wndProc's own module rather
+// than the parent's hInstance REAPER hands us. Registering against the parent would put the class
+// in REAPER's own module, where a second .vst3 (the other channel) sharing that hInstance could
+// collide on the (now channel-forked) name, and any lookup-by-class would resolve into the wrong
+// binary. Takes the address rather than naming wndProc directly so a free function in this
+// anonymous namespace doesn't need access to the private member.
+HMODULE moduleHandleFor(void* codeAddress) {
+    HMODULE mod = nullptr;
+    GetModuleHandleExW(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS |
+                            GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT,
+                        reinterpret_cast<LPCWSTR>(codeAddress), &mod);
+    return mod;
+}
 
 // The change-detection poll (WM_TIMER on the child window). A low-frequency UI-thread
 // timer: responsive enough that a recapture/ingest/assign refreshes within a bounded
@@ -105,8 +131,9 @@ void ReaSamplerEditor::attachedToParent() {
     HWND parent = static_cast<HWND>(systemWindow);
     if (!parent) return;
 
-    HINSTANCE hInst =
-        reinterpret_cast<HINSTANCE>(GetWindowLongPtr(parent, GWLP_HINSTANCE));
+    // Own module, not the parent's hInstance — see moduleHandleFor() above.
+    HINSTANCE hInst = reinterpret_cast<HINSTANCE>(
+        moduleHandleFor(reinterpret_cast<void*>(&ReaSamplerEditor::wndProc)));
     if (!hInst) hInst = GetModuleHandle(nullptr);
 
     static bool classRegistered = false;
@@ -114,7 +141,7 @@ void ReaSamplerEditor::attachedToParent() {
         WNDCLASSW wc{};
         wc.lpfnWndProc = &ReaSamplerEditor::wndProc;
         wc.hInstance = hInst;
-        wc.lpszClassName = kChildClassName;
+        wc.lpszClassName = childClassName().c_str();
         wc.hCursor = LoadCursor(nullptr, IDC_ARROW);
         // CS_DBLCLKS is what makes WM_LBUTTONDBLCLK arrive at all. It also REPLACES the second
         // WM_LBUTTONDOWN of a double-click, so every surface that counted two downs (Browse's
@@ -134,7 +161,7 @@ void ReaSamplerEditor::attachedToParent() {
     refreshFromBank();
 
     const ViewRect& r = getRect();
-    childHwnd_ = CreateWindowExW(0, kChildClassName, L"", WS_CHILD | WS_VISIBLE, 0, 0,
+    childHwnd_ = CreateWindowExW(0, childClassName().c_str(), L"", WS_CHILD | WS_VISIBLE, 0, 0,
                                  r.getWidth(), r.getHeight(), parent, nullptr, hInst, nullptr);
     if (childHwnd_) {
         SetWindowLongPtr(childHwnd_, GWLP_USERDATA, reinterpret_cast<LONG_PTR>(this));

src/shell/panel/CLAUDE.md

@@ -2,9 +2,9 @@
 
 ## Scope
 
-The REAPER-facing shell for the docked bank panel: the eight `bank_panel` split TUs
+The REAPER-facing shell for the docked bank panel: the nine `bank_panel` split TUs
 (`panel_window` / `panel_layout` / `panel_render` / `panel_input` / `panel_drag` /
-`panel_thumbnails` / `panel_audition` / `panel_bank_ops`, sharing state via
+`panel_drag_os` / `panel_thumbnails` / `panel_audition` / `panel_bank_ops`, sharing state via
 `panel_state.h`), plus `draw_kit`, the shared LICE draw shell also consumed by the
 VST3 editor (`shell/instrument/`).
 
@@ -47,12 +47,13 @@ live in `shell/bank_ops`, a sibling directory, not here.
 
 ## Modules
 
-- `bank_panel` (`shell/panel/`: `panel_window` / `panel_layout` / `panel_render` / `panel_input` / `panel_drag` / `panel_thumbnails` / `panel_audition` / `panel_bank_ops`, sharing state via `panel_state.h` — Q-W2 split of the former god-module into eight TUs) — docked LICE-drawn grid with three-zone layout: top toolbar (Capture → Placement, frequent acts only, via `action_bar`, short labels; Maintenance and the rarer Placement/Capture variants sit in the More (⋯) overflow menu via `overflow_menu`), bottom toolbar (four opposite-mode tag buttons + Show Both), and footer (`[Arrange|Design]` toggle, Tail button, Prune via `footer_bar`). Grid renders in sparse slot order with gap cells, drop dispatch, metadata overlay, and selection via `accent/tertiary` purple border. Draws through the L1 kit by palette role; OS drag-out via `drag_out` + `drag_out_win`. `panel_window` owns the SWELL dialog lifecycle + dialog proc + drop-target opt-in; `panel_layout` the toolbar/footer/menu rects + vertical-split geometry (the one geometry source both paint and hit-test read); `panel_render` the WM_PAINT draw; `panel_input` click/wheel/keyboard routing + the new-content auto-tag timer; `panel_drag` the hover + card-drag state machine + drop dispatch; `panel_thumbnails` the PCM→envelope thumbnail cache + the bank-change fingerprint pass; `panel_audition` the preview-playback engine; `panel_bank_ops` the menu/prompt UX skin over the promptless `shell/bank_ops` verbs. `draw_kit` (shared with the VST3 editor) stays a separate TU.
+- `bank_panel` (`shell/panel/`: `panel_window` / `panel_layout` / `panel_render` / `panel_input` / `panel_drag` / `panel_drag_os` / `panel_thumbnails` / `panel_audition` / `panel_bank_ops`, sharing state via `panel_state.h` — Q-W2 split of the former god-module into nine TUs) — docked LICE-drawn grid with three-zone layout: top toolbar (Capture → Placement, frequent acts only, via `action_bar`, short labels; Maintenance and the rarer Placement/Capture variants sit in the More (⋯) overflow menu via `overflow_menu`), bottom toolbar (four opposite-mode tag buttons + Show Both), and footer (`[Arrange|Design]` toggle, Tail button, Prune via `footer_bar`). Grid renders in sparse slot order with gap cells, drop dispatch, metadata overlay, and selection via `accent/tertiary` purple border. Draws through the L1 kit by palette role; OS drag-out via `drag_out` + `drag_out_win`. `panel_window` owns the SWELL dialog lifecycle + dialog proc + drop-target opt-in; `panel_layout` the toolbar/footer/menu rects + vertical-split geometry (the one geometry source both paint and hit-test read); `panel_render` the WM_PAINT draw; `panel_input` click/wheel/keyboard routing + the new-content auto-tag timer; `panel_drag` the hover + card-drag state machine + drop dispatch; `panel_drag_os` the OS hand-off/resume seam split out of `panel_drag`; `panel_thumbnails` the PCM→envelope thumbnail cache + the bank-change fingerprint pass; `panel_audition` the preview-playback engine; `panel_bank_ops` the menu/prompt UX skin over the promptless `shell/bank_ops` verbs. `draw_kit` (shared with the VST3 editor) stays a separate TU.
   - `panel_window` — SWELL dialog lifecycle + dialog proc + drop-target opt-in. The drop splits by extension: a `.rsbank` is a whole bank and routes to the package-import action (one NEW bank each), everything else keeps the audio-ingest route.
   - `panel_layout` — toolbar/footer/menu rects + vertical-split geometry (the one geometry source both paint and hit-test read).
   - `panel_render` — the WM_PAINT draw.
   - `panel_input` — click/wheel/keyboard routing + the new-content auto-tag timer.
   - `panel_drag` — the hover + card-drag state machine + drop dispatch.
+  - `panel_drag_os` — the OS hand-off/resume seam: the live re-ask the OS drag loop uses, the hand-off itself, and resuming the internal drag when the OS loop gives the gesture back.
   - `panel_thumbnails` — the PCM→envelope thumbnail cache + the bank-change fingerprint pass.
   - `panel_audition` — the preview-playback engine.
   - `panel_bank_ops` — the menu/prompt UX skin over the promptless `shell/bank_ops` verbs.

src/shell/panel/panel_drag.cpp

@@ -306,10 +306,19 @@ void onMouseMove(int x, int y, WPARAM wParam) {
     // A move with the button already up while still dragging means the release was missed (the
     // OS hand-off's own modal loop can eat a WM_LBUTTONUP, and coalescing can lose one too) —
     // treat it as the release now rather than leaving dragging stuck for the next plain click.
+#ifdef _WIN32
     if (g_panel.dragging && !(wParam & MK_LBUTTON)) {
         onLBtnUp(x, y);
         return;
     }
+#else
+    // SWELL never sets wParam on WM_MOUSEMOVE (swell-types.h ~1315), so the button-up test must
+    // read the physical key state instead of the message's own (always-zero) wParam.
+    if (g_panel.dragging && !(GetAsyncKeyState(VK_LBUTTON) & 0x8000)) {
+        onLBtnUp(x, y);
+        return;
+    }
+#endif
 
     // Hover feedback: resolve + repaint-on-change, but NOT during a drag (the drag owns
     // the visual feedback then — a drop-target highlight, not a hover).

src/shell/panel/panel_drag_os.cpp

@@ -1,6 +1,6 @@
-// panel_drag_os.cpp — the OS hand-off / resume seam split out of panel_drag.cpp (the ~600-line
-// file ceiling): the live re-ask the OS drag loop uses to decide whether to keep the drag, the
-// hand-off itself, and resuming the internal drag when the OS loop gives the gesture back.
+// panel_drag_os.cpp — the OS hand-off / resume seam split out of panel_drag.cpp: the live
+// re-ask the OS drag loop uses to decide whether to keep the drag, the hand-off itself, and
+// resuming the internal drag when the OS loop gives the gesture back.
 //
 // Compiled into the reaper_reasampler MODULE. No REAPER API functions are called directly here;
 // REAPER SDK types arrive via panel_state.h.

src/shell/panel/panel_state.h

@@ -556,8 +556,7 @@ struct LiveDrop {
 LiveDrop resolveLiveDrop(int x, int y);
 void applyDropCue(DropCue cue);
 
-// panel_drag_os.cpp — the OS hand-off / resume seam split out of panel_drag.cpp (the ~600-line
-// file ceiling).
+// panel_drag_os.cpp — the OS hand-off / resume seam split out of panel_drag.cpp.
 void handOffToOs();
 
 }  // namespace reasampler::panel