virtual_sdcard: add SDCARD_PRINT_FILE gcode

SDCARD_PRINT_FILE allows Klipper to load and start the print for any
gcode file within the virtual_sdcard path, including subdirectories.

Signed-off-by:  Eric Callahan <arksine.code@gmail.com>

klippy/extras/virtual_sdcard.py

@@ -5,6 +5,8 @@
 # This file may be distributed under the terms of the GNU GPLv3 license.
 import os, logging
 
+VALID_GCODE_EXTS = ['gcode', 'g', 'gco']
+
 class VirtualSD:
     def __init__(self, config):
         printer = config.get_printer()
@@ -28,6 +30,9 @@ class VirtualSD:
         self.gcode.register_command(
             "SDCARD_RESET_FILE", self.cmd_SDCARD_RESET_FILE,
             desc=self.cmd_SDCARD_RESET_FILE_help)
+        self.gcode.register_command(
+            "SDCARD_PRINT_FILE", self.cmd_SDCARD_PRINT_FILE,
+            desc=self.cmd_SDCARD_PRINT_FILE_help)
     def handle_shutdown(self):
         if self.work_timer is not None:
             self.must_pause_work = True
@@ -46,7 +51,21 @@ class VirtualSD:
         if self.work_timer is None:
             return False, ""
         return True, "sd_pos=%d" % (self.file_position,)
-    def get_file_list(self):
+    def get_file_list(self, check_subdirs=False):
+        if check_subdirs:
+            flist = []
+            for root, dirs, files in os.walk(
+                    self.sdcard_dirname, followlinks=True):
+                for name in files:
+                    ext = name[name.rfind('.')+1:]
+                    if ext not in VALID_GCODE_EXTS:
+                        continue
+                    full_path = os.path.join(root, name)
+                    r_path = full_path[len(self.sdcard_dirname) + 1:]
+                    size = os.path.getsize(full_path)
+                    flist.append((r_path, size))
+            return sorted(flist, key=lambda f: f[0].lower())
+        else:
             dname = self.sdcard_dirname
             try:
                 filenames = os.listdir(self.sdcard_dirname)
@@ -85,6 +104,17 @@ class VirtualSD:
             raise gcmd.error(
                 "SDCARD_RESET_FILE cannot be run from the sdcard")
         self._reset_file()
+    cmd_SDCARD_PRINT_FILE_help = "Loads a SD file and starts the print.  May "\
+        "include files in subdirectories."
+    def cmd_SDCARD_PRINT_FILE(self, gcmd):
+        if self.work_timer is not None:
+            raise gcmd.error("SD busy")
+        self._reset_file()
+        filename = gcmd.get("FILENAME")
+        if filename[0] == '/':
+            filename = filename[1:]
+        self._load_file(gcmd, filename, check_subdirs=True)
+        self.cmd_M24(gcmd)
     def cmd_M20(self, gcmd):
         # List SD card
         files = self.get_file_list()
@@ -99,10 +129,7 @@ class VirtualSD:
         # Select SD file
         if self.work_timer is not None:
             raise gcmd.error("SD busy")
-        if self.current_file is not None:
+        self._reset_file()
-            self.current_file.close()
-            self.current_file = None
-            self.file_position = self.file_size = 0
         try:
             orig = gcmd.get_commandline()
             filename = orig[orig.find("M23") + 4:].split()[0].strip()
@@ -112,7 +139,9 @@ class VirtualSD:
             raise gcmd.error("Unable to extract filename")
         if filename.startswith('/'):
             filename = filename[1:]
-        files = self.get_file_list()
+        self._load_file(gcmd, filename)
+    def _load_file(self, gcmd, filename, check_subdirs=False):
+        files = self.get_file_list(check_subdirs)
         files_by_lower = { fname.lower(): fname for fname, fsize in files }
         try:
             fname = files_by_lower[filename.lower()]