print_stats: add `SET_PRINT_STATS_INFO` G-Code for pass slicer variables to Klipper (#5726)

This adds a gcode command that can be used insight the slicer to pass the total layer count and current layer information.

Signed-off-by: Stefan Dej <meteyou@gmail.com>

3 files changed, 46 insertions, 3 deletions

diff --git a/docs/G-Codes.md b/docs/G-Codes.md
index 3e4e177f6..d9cefd80b 100644
--- a/docs/G-Codes.md
+++ b/docs/G-Codes.md
@@ -888,6 +888,18 @@ the paused state is fresh for each print.
 #### CANCEL_PRINT
 `CANCEL_PRINT`: Cancels the current print.
 
+### [print_stats]
+
+The print_stats module is automatically loaded.
+
+#### SET_PRINT_STATS_INFO
+`SET_PRINT_STATS_INFO [TOTAL_LAYER=<total_layer_count>] [CURRENT_LAYER=
+<current_layer>]`: Pass slicer info like layer act and total to Klipper.
+Add `SET_PRINT_STATS_INFO [TOTAL_LAYER=<total_layer_count>]` to your
+slicer start gcode section and `SET_PRINT_STATS_INFO [CURRENT_LAYER=
+<current_layer>]` at the layer change gcode section to pass layer
+information from your slicer to Klipper.
+
 ### [probe]
 
 The following commands are available when a
diff --git a/docs/Status_Reference.md b/docs/Status_Reference.md
index 99d4f0f31..e6595ddbb 100644
--- a/docs/Status_Reference.md
+++ b/docs/Status_Reference.md
@@ -330,8 +330,12 @@ The following information is available in the `print_stats` object
 [virtual_sdcard](Config_Reference.md#virtual_sdcard) config section is
 defined):
 - `filename`, `total_duration`, `print_duration`, `filament_used`,
-  `state`, `message`: Estimated information about the current print
-  when a virtual_sdcard print is active.
+  `state`, `message`: Estimated information about the current print when a
+  virtual_sdcard print is active.
+- `info.total_layer`: The total layer value of the last `SET_PRINT_STATS_INFO
+   TOTAL_LAYER=<value>` G-Code command.
+- `info.current_layer`: The current layer value of the last
+  `SET_PRINT_STATS_INFO CURRENT_LAYER=<value>` G-Code command.
 
 ## probe
 
diff --git a/klippy/extras/print_stats.py b/klippy/extras/print_stats.py
index 9589aedea..668cd7d0c 100644
--- a/klippy/extras/print_stats.py
+++ b/klippy/extras/print_stats.py
@@ -10,6 +10,11 @@ class PrintStats:
         self.gcode_move = printer.load_object(config, 'gcode_move')
         self.reactor = printer.get_reactor()
         self.reset()
+        # Register commands
+        self.gcode = printer.lookup_object('gcode')
+        self.gcode.register_command(
+            "SET_PRINT_STATS_INFO", self.cmd_SET_PRINT_STATS_INFO,
+            desc=self.cmd_SET_PRINT_STATS_INFO_help)
     def _update_filament_usage(self, eventtime):
         gc_status = self.gcode_move.get_status(eventtime)
         cur_epos = gc_status['position'].e
@@ -59,6 +64,24 @@ class PrintStats:
             self.init_duration = self.total_duration - \
                 self.prev_pause_duration
         self.print_start_time = None
+    cmd_SET_PRINT_STATS_INFO_help = "Pass slicer info like layer act and " \
+                                    "total to klipper"
+    def cmd_SET_PRINT_STATS_INFO(self, gcmd):
+        total_layer = gcmd.get_int("TOTAL_LAYER", self.info_total_layer, \
+                                   minval=0)
+        current_layer = gcmd.get_int("CURRENT_LAYER", self.info_current_layer, \
+                                     minval=0)
+        if total_layer == 0:
+            self.info_total_layer = None
+            self.info_current_layer = None
+        elif total_layer != self.info_total_layer:
+            self.info_total_layer = total_layer
+            self.info_current_layer = 0
+
+        if self.info_total_layer is not None and \
+                current_layer is not None and \
+                current_layer != self.info_current_layer:
+            self.info_current_layer = min(current_layer, self.info_total_layer)
     def reset(self):
         self.filename = self.error_message = ""
         self.state = "standby"
@@ -66,6 +89,8 @@ class PrintStats:
         self.filament_used = self.total_duration = 0.
         self.print_start_time = self.last_pause_time = None
         self.init_duration = 0.
+        self.info_total_layer = None
+        self.info_current_layer = None
     def get_status(self, eventtime):
         time_paused = self.prev_pause_duration
         if self.print_start_time is not None:
@@ -86,7 +111,9 @@ class PrintStats:
             'print_duration': print_duration,
             'filament_used': self.filament_used,
             'state': self.state,
-            'message': self.error_message
+            'message': self.error_message,
+            'info': {'total_layer': self.info_total_layer,
+                     'current_layer': self.info_current_layer}
         }
 
 def load_config(config):