Specify plate index for the 3mf workflow (#14404)

feat: forward plateindex for index-coded .gcode.3mf uploads

Gcode inside a .gcode.3mf is index-coded (Metadata/plate_<N>.gcode) and a
bundle may carry several, so the upload must name which plate to print —
even a single-plate bundle, since its entry is still indexed.

A 1-based plate index is stored in PrintHostUpload::extended_info when use_3mf
is set; the OctoPrint and Moonraker hosts forward it as a `plateindex` form
field. Servers that don't use it ignore the unknown field, so the plain G-code
path is unchanged.

src/slic3r/GUI/Plater.cpp

@@ -16114,6 +16114,8 @@ void Plater::send_gcode_legacy(int plate_idx, Export3mfProgressFn proFn)
     const bool  use_3mf     = use_3mf_opt != nullptr && use_3mf_opt->value;
 
     upload_job.upload_data.use_3mf = use_3mf;
+    // Orca: the concrete plate to export/send (PLATE_CURRENT_IDX resolves to the current plate).
+    const int resolved_plate_idx = plate_idx == PLATE_CURRENT_IDX ? get_partplate_list().get_curr_plate_index() : plate_idx;
 
     // Obtain default output path
     fs::path default_output_file;
@@ -16203,7 +16205,6 @@ void Plater::send_gcode_legacy(int plate_idx, Export3mfProgressFn proFn)
             DynamicPrintConfig          cfg                 = wxGetApp().preset_bundle->full_config();
             const auto*                 filament_color      = dynamic_cast<const ConfigOptionStrings*>(cfg.option("filament_colour"));
             const auto*                 filament_id_opt     = dynamic_cast<const ConfigOptionStrings*>(cfg.option("filament_ids"));
-            const int                   resolved_plate_idx  = plate_idx == PLATE_CURRENT_IDX ? get_partplate_list().get_curr_plate_index() : plate_idx;
             auto enrich_project_filaments = [&](std::vector<FilamentInfo>& filaments) {
                 for (auto& filament : filaments) {
                     if (filament.id < 0)
@@ -16269,6 +16270,15 @@ void Plater::send_gcode_legacy(int plate_idx, Export3mfProgressFn proFn)
         upload_job.upload_data.group       = pDlg->group();
         upload_job.upload_data.storage     = pDlg->storage();
         upload_job.upload_data.extended_info = pDlg->extendedInfo();
+        // Orca: gcode inside a .gcode.3mf is index-coded (Metadata/plate_<N>.gcode) and a bundle may
+        // carry several of them, so the upload must name which plate to print via a 1-based plateindex.
+        // Even a single-plate bundle needs it, since its gcode entry is still indexed. The host upload
+        // forwards the field and servers that don't use it ignore it. "All plates" points at the
+        // current plate — the bundle still carries every plate's gcode.
+        if (use_3mf) {
+            const int plateindex = (plate_idx == PLATE_ALL_IDX ? get_partplate_list().get_curr_plate_index() : resolved_plate_idx) + 1;
+            upload_job.upload_data.extended_info["plateindex"] = std::to_string(plateindex);
+        }
     }
 
     // Show "Is printer clean" dialog for PrusaConnect - Upload and print.
@@ -16280,8 +16290,7 @@ void Plater::send_gcode_legacy(int plate_idx, Export3mfProgressFn proFn)
 
     if (use_3mf) {
         // Process gcode
-        const int export_plate_idx = plate_idx == PLATE_CURRENT_IDX ? get_partplate_list().get_curr_plate_index() : plate_idx;
+        const int result = send_gcode(resolved_plate_idx, nullptr);
-        const int result = send_gcode(export_plate_idx, nullptr);
 
         if (result < 0) {
             wxString msg = _L("Abnormal print file data. Please slice again");

src/slic3r/Utils/Moonraker.cpp

@@ -237,18 +237,26 @@ bool Moonraker::upload(PrintHostUpload upload_data, ProgressFn progress_fn, Erro
     bool result = true;
     std::string uploaded_path;
 
-    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% to %3% (root=%4%, filename=%5%, start_print=%6%)")
+    //ORCA: gcode inside a .gcode.3mf is index-coded (Metadata/plate_<N>.gcode), so the upload names the
+    //      plate via a 1-based `plateindex` (set only in the .3mf path, see Plater::send_gcode_legacy);
+    //      servers that don't use it ignore the unknown form field.
+    const std::string plateindex = upload_data.extended("plateindex");
+
+    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% to %3% (root=%4%, filename=%5%, plateindex=%6%, start_print=%7%)")
         % name
         % upload_data.source_path
         % url
         % root
         % upload_filename.string()
+        % (plateindex.empty() ? "-" : plateindex)
         % (upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false");
 
     auto http = Http::post(std::move(url));
     set_auth(http);
-    http.form_add("root", root)
+    http.form_add("root", root);
-        .form_add_file("file", upload_data.source_path.string(), upload_filename.string())
+    if (!plateindex.empty())
+        http.form_add("plateindex", plateindex);
+    http.form_add_file("file", upload_data.source_path.string(), upload_filename.string())
         .on_complete([&](std::string body, unsigned status) {
             BOOST_LOG_TRIVIAL(debug) << boost::format("%1%: upload HTTP %2%: %3%") % name % status % body;
             try {

src/slic3r/Utils/OctoPrint.cpp

@@ -345,13 +345,15 @@ bool OctoPrint::upload_inner_with_resolved_ip(PrintHostUpload upload_data, Progr
 
     info_fn(L"resolve", boost::nowide::widen(url));
 
-    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% at %3%, filename: %4%, path: %5%, print: %6%")
+    const std::string plateindex = upload_data.extended("plateindex");
+    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% at %3%, filename: %4%, path: %5%, print: %6%, plateindex: %7%")
         % name
         % upload_data.source_path
         % url
         % upload_filename.string()
         % upload_parent_path.string()
-        % (upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false");
+        % (upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false")
+        % (plateindex.empty() ? "-" : plateindex);
 
     auto http = Http::post(url);//std::move(url));
     // "Host" header is necessary here. We have resolved IP address and subsituted it into "url" variable.
@@ -362,8 +364,13 @@ bool OctoPrint::upload_inner_with_resolved_ip(PrintHostUpload upload_data, Progr
     http.header("Host", Http::get_host_header_value(m_host));
     set_auth(http);
     http.form_add("print", upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false")
-        .form_add("path", upload_parent_path.string())      // XXX: slashes on windows ???
+        .form_add("path", upload_parent_path.string());     // XXX: slashes on windows ???
-        .form_add_file("file", upload_data.source_path.string(), upload_filename.string())
+    //ORCA: gcode inside a .gcode.3mf is index-coded (Metadata/plate_<N>.gcode), so the upload names the
+    //      plate via a 1-based `plateindex` (see Plater::send_gcode_legacy); servers that don't use it
+    //      ignore the unknown form field.
+    if (!plateindex.empty())
+        http.form_add("plateindex", plateindex);
+    http.form_add_file("file", upload_data.source_path.string(), upload_filename.string())
   
         .on_complete([&](std::string body, unsigned status) {
             BOOST_LOG_TRIVIAL(debug) << boost::format("%1%: File uploaded: HTTP %2%: %3%") % name % status % body;
@@ -429,13 +436,15 @@ bool OctoPrint::upload_inner_with_host(PrintHostUpload upload_data, ProgressFn p
     }
 #endif // _WIN32
 
-    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% at %3%, filename: %4%, path: %5%, print: %6%")
+    const std::string plateindex = upload_data.extended("plateindex");
+    BOOST_LOG_TRIVIAL(info) << boost::format("%1%: Uploading file %2% at %3%, filename: %4%, path: %5%, print: %6%, plateindex: %7%")
         % name
         % upload_data.source_path
         % url
         % upload_filename.string()
         % upload_parent_path.string()
-        % (upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false");
+        % (upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false")
+        % (plateindex.empty() ? "-" : plateindex);
 
     auto http = Http::post(std::move(url));
 #ifdef WIN32
@@ -449,8 +458,13 @@ bool OctoPrint::upload_inner_with_host(PrintHostUpload upload_data, ProgressFn p
 #endif // _WIN32
     set_auth(http);
     http.form_add("print", upload_data.post_action == PrintHostPostUploadAction::StartPrint ? "true" : "false")
-        .form_add("path", upload_parent_path.string())      // XXX: slashes on windows ???
+        .form_add("path", upload_parent_path.string());     // XXX: slashes on windows ???
-        .form_add_file("file", upload_data.source_path.string(), upload_filename.string())
+    //ORCA: gcode inside a .gcode.3mf is index-coded (Metadata/plate_<N>.gcode), so the upload names the
+    //      plate via a 1-based `plateindex` (see Plater::send_gcode_legacy); servers that don't use it
+    //      ignore the unknown form field.
+    if (!plateindex.empty())
+        http.form_add("plateindex", plateindex);
+    http.form_add_file("file", upload_data.source_path.string(), upload_filename.string())
         .on_complete([&](std::string body, unsigned status) {
             BOOST_LOG_TRIVIAL(debug) << boost::format("%1%: File uploaded: HTTP %2%: %3%") % name % status % body;
         })

src/slic3r/Utils/PrintHost.hpp

@@ -29,7 +29,7 @@ ENABLE_ENUM_BITMASK_OPERATORS(PrintHostPostUploadAction);
 
 struct PrintHostUpload
 {
-    bool use_3mf;
+    bool use_3mf { false };
     boost::filesystem::path source_path;
     boost::filesystem::path upload_path;
 
@@ -40,6 +40,13 @@ struct PrintHostUpload
 
     // Some extended parameters for different upload methods.
     std::map<std::string, std::string> extended_info;
+
+    // Safe accessor for an extended_info entry; returns `def` when the key is absent.
+    std::string extended(const std::string &key, const std::string &def = {}) const
+    {
+        auto it = extended_info.find(key);
+        return it != extended_info.end() ? it->second : def;
+    }
 };
 
 class PrintHost