Fix a M73 and layer number regression s (#8435)

# Description

Fixed two regressions:
1. Total layer number was missing for BBL printers
2. M73 remaining info was wrong when ARC fitting is enabled.

# Screenshots/Recordings/Graphs

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## Tests

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changes made in this PR.
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src/libslic3r/GCode/GCodeProcessor.cpp

@@ -4415,33 +4415,43 @@ void GCodeProcessor::run_post_process()
                         }
                     }
                 }
-            }
-            else if (line == reserved_tag(ETags::Estimated_Printing_Time_Placeholder)) {
+            } else if (line == reserved_tag(ETags::Estimated_Printing_Time_Placeholder)) {
                 for (size_t i = 0; i < static_cast<size_t>(PrintEstimatedStatistics::ETimeMode::Count); ++i) {
-                    const TimeMachine& machine = m_time_processor.machines[i];
-                    PrintEstimatedStatistics::ETimeMode mode = static_cast<PrintEstimatedStatistics::ETimeMode>(i);
+                    const TimeMachine&                  machine = m_time_processor.machines[i];
+                    PrintEstimatedStatistics::ETimeMode mode    = static_cast<PrintEstimatedStatistics::ETimeMode>(i);
                     if (mode == PrintEstimatedStatistics::ETimeMode::Normal || machine.enabled) {
                         char buf[128];
-                        sprintf(buf, "; estimated printing time (%s mode) = %s\n",
-                            (mode == PrintEstimatedStatistics::ETimeMode::Normal) ? "normal" : "silent",
-                            get_time_dhms(machine.time).c_str());
+                        if (!s_IsBBLPrinter)
+                            // Orca: compatibility with klipper_estimator
+                            sprintf(buf, "; estimated printing time (%s mode) = %s\n",
+                                    (mode == PrintEstimatedStatistics::ETimeMode::Normal) ? "normal" : "silent",
+                                    get_time_dhms(machine.time).c_str());
+                        else {
+                            sprintf(buf, "; model printing time: %s; total estimated time: %s\n",
+                                    get_time_dhms(machine.time - machine.prepare_time).c_str(), get_time_dhms(machine.time).c_str());
+                        }
                         export_lines.append_line(buf);
-                        processed = true;
                     }
                 }
                 for (size_t i = 0; i < static_cast<size_t>(PrintEstimatedStatistics::ETimeMode::Count); ++i) {
-                    const TimeMachine& machine = m_time_processor.machines[i];
-                    PrintEstimatedStatistics::ETimeMode mode = static_cast<PrintEstimatedStatistics::ETimeMode>(i);
+                    const TimeMachine&                  machine = m_time_processor.machines[i];
+                    PrintEstimatedStatistics::ETimeMode mode    = static_cast<PrintEstimatedStatistics::ETimeMode>(i);
                     if (mode == PrintEstimatedStatistics::ETimeMode::Normal || machine.enabled) {
                         char buf[128];
                         sprintf(buf, "; estimated first layer printing time (%s mode) = %s\n",
-                            (mode == PrintEstimatedStatistics::ETimeMode::Normal) ? "normal" : "silent",
-                            get_time_dhms(machine.prepare_time).c_str());
+                                (mode == PrintEstimatedStatistics::ETimeMode::Normal) ? "normal" : "silent",
+                                get_time_dhms(machine.prepare_time).c_str());
                         export_lines.append_line(buf);
                         processed = true;
                     }
                 }
             }
+            // Orca: write total layer number, this is used by Bambu printers only as of now
+            else if (line == reserved_tag(ETags::Total_Layer_Number_Placeholder)) {
+                char buf[128];
+                sprintf(buf, "; total layer number: %u\n", m_layer_id);
+                export_lines.append_line(buf);
+            }
         }
 
         return processed;

src/libslic3r/GCode/GCodeProcessor.hpp

@@ -380,7 +380,7 @@ class Print;
             EMoveType move_type{ EMoveType::Noop };
             ExtrusionRole role{ erNone };
             unsigned int g1_line_id{ 0 };
-            unsigned int remaining_internal_g1_lines;
+            unsigned int remaining_internal_g1_lines{ 0 };
             unsigned int layer_id{ 0 };
             float distance{ 0.0f }; // mm
             float acceleration{ 0.0f }; // mm/s^2
@@ -429,7 +429,7 @@ class Print;
             struct G1LinesCacheItem
             {
                 unsigned int id;
-                unsigned int remaining_internal_g1_lines;
+                unsigned int remaining_internal_g1_lines{ 0 };
                 float elapsed_time;
             };