Reworked Inkscape command line generation.

The old version was brittle and made conditional operations hard.

2 files changed, 148 insertions, 92 deletions

diff --git a/support/inkscape/__main__.py b/support/inkscape/__main__.py
index 3052e6f..7b3ea1a 100644
--- a/support/inkscape/__main__.py
+++ b/support/inkscape/__main__.py
@@ -1,114 +1,50 @@
-import sys, os, xml.etree.ElementTree, shutil
+import sys, os, shutil
 from lib import util
-from . import effect
+from . import effect, inkscape
 
 
-def _export_dxf(in_path, out_path, layers):
-	dxf_effect = effect.ExportEffect(layers)
-	dxf_effect.affect(args = [in_path], output = False)
+def _unfuck_svg_document(temp_svg_path):
+	"""
+	Unfucks an SVG document so is can be processed by the better_dxf_export plugin (or what's left of it).
+	"""
 	
-	with open(out_path, 'w') as file:
-		dxf_effect.write_dxf(file)
-
-
-def _get_inkscape_layers(svg_path):
-	document = xml.etree.ElementTree.parse(svg_path)
+	command_line = inkscape.InkscapeCommandLine(temp_svg_path)
+	layers = command_line.layers
 	
-	def iter_layers():
-		nodes = document.findall(
-			'{http://www.w3.org/2000/svg}g[@{http://www.inkscape.org/namespaces/inkscape}groupmode="layer"]')
-		
-		for i in nodes:
-			inkscape_name = i.get('{http://www.inkscape.org/namespaces/inkscape}label').strip()
-			
-			if inkscape_name.endswith(']'):
-				dxf_name, args = inkscape_name[:-1].rsplit('[', 1)
-				
-				dxf_name = dxf_name.strip()
-				args = args.strip()
-				
-				use_paths = 'p' in args
-			else:
-				use_paths = False
-				dxf_name = inkscape_name
-			
-			yield effect.Layer(inkscape_name, dxf_name, use_paths = use_paths)
+	command_line.apply_to_document('LayerUnlockAll', 'LayerShowAll')
 	
-	return list(iter_layers())
-
-
-def _inkscape(svg_path, verbs):
-	def iter_args():
-		yield os.environ['INKSCAPE']
+	layer_copies = []
+	
+	for i in layers:
+		layer_copy = command_line.duplicate_layer(i)
+		layer_copies.append(layer_copy)
 		
-		for i in verbs:
-			yield '--verb'
-			yield i
+		command_line.apply_to_layer_content(layer_copy, 'ObjectToPath')
+		command_line.apply_to_layer_content(layer_copy, 'SelectionUnGroup')
 		
-		yield svg_path
+		if not i.use_paths:
+			command_line.apply_to_layer_content(layer_copy, 'StrokeToPath')
+			command_line.apply_to_layer_content(layer_copy, 'SelectionUnion')
 	
-	util.command(list(iter_args()))
-
-
-def _unfuck_svg_document(temp_svg_path, layers):
-	"""
-	Unfucks an SVG document so is can be processed by the better_dxf_export plugin (or what's left of it).
-	"""
+	for original, copy in zip(layers, layer_copies):
+		command_line.clear_layer(original)
+		command_line.move_content(copy, original)
+		command_line.delete_layer(copy)
 	
-	def iter_inkscape_verbs():
-		yield 'LayerUnlockAll'
-		yield 'LayerShowAll'
-
-		# Go to the first layer.
-		for _ in layers:
-			yield 'LayerPrev'
-		
-		# Copy each layer and flatten it to a single path object.
-		for i in layers:
-			yield 'LayerDuplicate'
-			yield 'EditSelectAll'
-			yield 'ObjectToPath'
-			yield 'EditSelectAll'
-			yield 'SelectionUnGroup'
-			
-			if not i.use_paths:
-				yield 'EditSelectAll'
-				yield 'StrokeToPath'
-				yield 'EditSelectAll'
-				yield 'SelectionUnion'
-			
-			yield 'LayerNext'
-		
-		# Go to the first layer again.
-		for _ in range(2 * len(layers)):
-			yield 'LayerPrev'
-		
-		# Move the flattened shapes to the original layers.
-		for _ in layers:
-			yield 'EditSelectAll'
-			yield 'EditDelete'
-			yield 'LayerNext'
-			
-			yield 'EditSelectAll'
-			yield 'LayerMoveToPrev'
-			yield 'LayerNext'
-			yield 'LayerDelete'
-		
-		yield 'FileSave'
-		yield 'FileClose'
-		yield 'FileQuit'
+	command_line.apply_to_document('FileSave', 'FileClose', 'FileQuit')
 	
-	_inkscape(temp_svg_path, list(iter_inkscape_verbs()))
+	command_line.run()
 
 
 def main(in_path, out_path):
+	_, out_suffix = os.path.splitext(out_path)
+	
 	with util.TemporaryDirectory() as temp_dir:
 		temp_svg_path = os.path.join(temp_dir, 'temp.svg')
 		
 		shutil.copyfile(in_path, temp_svg_path)
 		
-		layers = _get_inkscape_layers(temp_svg_path)
-		_unfuck_svg_document(temp_svg_path, layers)
+		_unfuck_svg_document(temp_svg_path)
 		
 		_export_dxf(temp_svg_path, out_path, layers)
 
diff --git a/support/inkscape/inkscape.py b/support/inkscape/inkscape.py
new file mode 100644
index 0000000..09e7a7b
--- /dev/null
+++ b/support/inkscape/inkscape.py
@@ -0,0 +1,120 @@
+import os
+import xml.etree.ElementTree as etree
+from lib import util
+
+
+def get_inkscape_layers(svg_path):
+	document = etree.parse(svg_path)
+	
+	def iter_layers():
+		nodes = document.findall(
+			'{http://www.w3.org/2000/svg}g[@{http://www.inkscape.org/namespaces/inkscape}groupmode="layer"]')
+		
+		for i in nodes:
+			inkscape_name = i.get('{http://www.inkscape.org/namespaces/inkscape}label').strip()
+			
+			if inkscape_name.endswith(']'):
+				dxf_name, args = inkscape_name[:-1].rsplit('[', 1)
+				
+				dxf_name = dxf_name.strip()
+				args = args.strip()
+				
+				use_paths = 'p' in args
+			else:
+				use_paths = False
+				dxf_name = inkscape_name
+			
+			yield Layer(inkscape_name, dxf_name, use_paths = use_paths)
+	
+	return list(iter_layers())
+
+
+def _inkscape(svg_path, verbs):
+	def iter_args():
+		yield os.environ['INKSCAPE']
+		
+		for i in verbs:
+			yield '--verb'
+			yield i
+		
+		yield svg_path
+	
+	util.command(list(iter_args()))
+
+
+class Layer(object):
+	def __init__(self, inkscape_name, export_name, use_paths):
+		self.inkscape_name = inkscape_name
+		self.export_name = export_name
+		self.use_paths = use_paths
+
+
+class InkscapeCommandLine(object):
+	def __init__(self, path):
+		self._path = path
+		self._layers = get_inkscape_layers(path)
+		self._current_layer_index = None
+		self._verbs = []
+	
+	def apply_to_document(self, *verb):
+		self._verbs.extend(verb)
+	
+	def apply_to_layer(self, layer, *verb):
+		self._go_to_layer(layer)
+		self.apply_to_document(*verb)
+	
+	def select_all_in_layer(self, layer):
+		self.apply_to_layer(layer, 'EditSelectAll')
+	
+	def apply_to_layer_content(self, layer, *verbs):
+		self.select_all_in_layer(layer)
+		self.apply_to_document(*verbs)
+	
+	def _go_to_layer(self, layer, with_selection = False):
+		if self._current_layer_index is None:
+			# Initialize to a known state.
+			self._current_layer_index = len(self._layers) - 1
+			self._go_to_layer(self._layers[0])
+		
+		target_index = self._layers.index(layer)
+		
+		while True:
+			if self._current_layer_index < target_index:
+				self.apply_to_document('LayerMoveToNext' if with_selection else 'LayerNext')
+				self._current_layer_index += 1
+			elif self._current_layer_index > target_index:
+				self.apply_to_document('LayerMoveToPrev' if with_selection else 'LayerPrev')
+				self._current_layer_index -= 1
+			else:
+				break
+	
+	def duplicate_layer(self, layer):
+		self.apply_to_layer(layer, 'LayerDuplicate')
+		
+		# Inkscape 0.91 places a duplicated layer above (after) the selected one and selects the new layer.
+		new_layer = Layer(layer.inkscape_name + ' copy', layer.export_name, layer.use_paths)
+		self._current_layer_index += 1
+		self._layers.insert(self._current_layer_index, new_layer)
+		
+		return new_layer
+	
+	def delete_layer(self, layer):
+		self.apply_to_layer(layer, 'LayerDelete')
+		
+		# Inkscape 0.91 selects the layer above (after) the deleted layer.
+		del self._layers[self._current_layer_index]
+	
+	def clear_layer(self, layer):
+		self.select_all_in_layer(layer)
+		self.apply_to_document('EditDelete')
+	
+	def move_content(self, source_layer, target_layer):
+		self.select_all_in_layer(source_layer)
+		self._go_to_layer(target_layer, True)
+	
+	def run(self):
+		_inkscape(self._path, self._verbs)
+	
+	@property
+	def layers(self):
+		return list(self._layers)