prevent using --red (two color printing) if not supported by model

brother_ql/brother_ql_create.py

@@ -71,6 +71,9 @@ def create_label(qlr, image, label_size, threshold=70, cut=True, dither=False, c
     threshold = 100.0 - threshold
     threshold = min(255, max(0, int(threshold/100.0 * 255))) # from percent to pixel val
 
+    if red and not qlr.two_color_support:
+        raise BrotherQLUnsupportedCmd('Printing in red is not supported with the selected model.')
+
     if isinstance(image, Image.Image):
         im = image
     elif isinstance(image, (unicode, str)):

brother_ql/devicedependent.py

@@ -171,3 +171,9 @@ compressionsupport = [
   'QL-810W',
   'QL-820NWB',
 ]
+
+two_color_support = [
+  'QL-800',
+  'QL-810W',
+  'QL-820NWB',
+]

brother_ql/raster.py

@@ -16,6 +16,7 @@ from .devicedependent import models, \
                              compressionsupport, \
                              cuttingsupport, \
                              expandedmode, \
+                             two_color_support, \
                              modesetting
 
 from . import BrotherQLError, BrotherQLUnsupportedCmd, BrotherQLUnknownModel, BrotherQLRasterError
@@ -66,6 +67,10 @@ class BrotherQLRaster(object):
         """
         self._warn(problem, kind=BrotherQLUnsupportedCmd)
 
+    @property
+    def two_color_support(self):
+        return self.model in two_color_support
+
     def add_initialize(self):
         self.page_number = 0
         self.data += b'\x1B\x40' # ESC @
@@ -150,6 +155,9 @@ class BrotherQLRaster(object):
         if self.model not in expandedmode:
             self.unsupported("Trying to set expanded mode (dpi/cutting at end) on a printer that doesn't support it")
             return
+        if self.two_color_printing and not self.two_color_support:
+            self.unsupported("Trying to set two_color_printing in expanded mode on a printer that doesn't support it.")
+            return
         self.data += b'\x1B\x69\x4B' # ESC i K
         flags = 0x00
         flags |= self.cut_at_end << 3