feat(S8): ingest through the bank — capture/import/drop into bank + assign to active instance

src/bank_panel.cpp

@@ -61,6 +61,7 @@
 #include "draw_kit.h"      // kit text() over cached AA fonts — retires GDI DrawText (L1)
 #include "footer_bar.h"    // pure footer LEFT-group layout: toggle + count + Tail button (L4)
 #include "guid_diff.h"     // GuidBaseline — new-content detection (D2 Wave 2)
+#include "ingest.h"        // ingestDroppedFiles — S8 drop-onto-panel ingest
 #include "item_read.h"     // itemGuid / itemLaneName — shared item-read seam (D2 W3-B)
 #include "lane_keys.h"     // managed/manual lane heuristic (D2 Wave 2)
 #include "mode_enable.h"   // opposite-mode tag-button enablement predicate (pure, L5)
@@ -82,6 +83,7 @@
 #ifdef _WIN32
 #include <windows.h>
 #include <windowsx.h>  // GET_X_LPARAM / GET_Y_LPARAM (SWELL supplies them on mac/linux)
+#include <shellapi.h>  // DragAcceptFiles / DragQueryFile / DragFinish — S8 drop ingest
 #else
 #include <pthread.h>
 #endif
@@ -3075,8 +3077,35 @@ void handleRightClick(int x, int y) {
 
 // --- Dialog proc + docking ----------------------------------------------------
 
+// Decodes a WM_DROPFILES HDROP into the dropped file paths (absolute, OS-native) and hands
+// them to the S8 ingest path. Multi-file drop: ingestDroppedFiles imports all and assigns
+// the first. Always DragFinish's the HDROP (frees the shell-allocated drop buffer) on every
+// path. DragQueryFile(hDrop, 0xFFFFFFFF, ...) returns the file count; then each path is
+// queried by index. Both Win32 and SWELL expose DragQueryFile/DragFinish with this contract.
+void handleDropFiles(HDROP hDrop) {
+    std::vector<std::string> paths;
+    const UINT count = DragQueryFile(hDrop, 0xFFFFFFFF, nullptr, 0);
+    paths.reserve(count);
+    for (UINT i = 0; i < count; ++i) {
+        // Query the required length first (excludes the NUL), then read into a sized buffer.
+        const UINT len = DragQueryFile(hDrop, i, nullptr, 0);
+        if (len == 0) continue;
+        std::vector<char> buf(static_cast<std::size_t>(len) + 1, '\0');
+        DragQueryFile(hDrop, i, buf.data(), static_cast<UINT>(buf.size()));
+        std::string p(buf.data());
+        if (!p.empty()) paths.push_back(std::move(p));
+    }
+    DragFinish(hDrop);
+    if (!paths.empty()) ingestDroppedFiles(paths);
+}
+
 WDL_DLGRET dlgProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam) {
     switch (msg) {
+        case WM_DROPFILES:
+            // S8 drop-onto-panel ingest: OS file drop on the docked panel HWND -> import
+            // into the active bank + assign the first. wParam is the HDROP.
+            handleDropFiles(reinterpret_cast<HDROP>(wParam));
+            return 0;
         case WM_PAINT: {
             PAINTSTRUCT ps;
             HDC hdc = BeginPaint(hwnd, &ps);
@@ -3172,6 +3201,17 @@ void openPanel() {
     DockWindowActivate(g_panel.hwnd);
     g_panel.open = true;
 
+    // S8: accept OS file drops on the panel HWND (WM_DROPFILES routes to handleDropFiles).
+    // DragAcceptFiles is a native Win32 shell call (shellapi.h); SWELL does NOT expose it,
+    // so the opt-in is Windows-only here. The primary/shipped platform is Windows (the VST3
+    // instrument the drop assigns to is Windows-only, D5); a mac/linux drop-registration
+    // surface is out of scope for this dispatch. WM_DROPFILES handling itself uses
+    // DragQueryFile/DragFinish, which SWELL DOES provide, so a drop delivered by other means
+    // would still ingest — only the accept opt-in is gated.
+#ifdef _WIN32
+    DragAcceptFiles(g_panel.hwnd, TRUE);
+#endif
+
     registerAccel();
 
     reconcileShownBank();