move StitchGroup into lib.stitch_plan

1 files changed, 34 insertions, 0 deletions

diff --git a/lib/stitch_plan/stitch_group.py b/lib/stitch_plan/stitch_group.py
new file mode 100644
index 00000000..d1e6bae7
--- /dev/null
+++ b/lib/stitch_plan/stitch_group.py
@@ -0,0 +1,34 @@
+class StitchGroup:
+    """A collection of Stitch objects with attached instructions.
+
+    StitchGroups will later be combined to make ColorBlocks, which in turn are
+    combined to make a StitchPlan.  Jump stitches are allowed between
+    StitchGroups, but not between stitches inside a StitchGroup.  This means
+    that EmbroideryElement classes should produce multiple StitchGroups only if
+    they want to allow for the possibility of jump stitches to be added in
+    between them by the stitch plan generation code.
+    """
+
+    def __init__(self, color=None, stitches=None, trim_after=False, stop_after=False, tie_modus=0, stitch_as_is=False):
+        self.color = color
+        self.stitches = stitches or []
+        self.trim_after = trim_after
+        self.stop_after = stop_after
+        self.tie_modus = tie_modus
+        self.stitch_as_is = stitch_as_is
+
+    def __add__(self, other):
+        if isinstance(other, StitchGroup):
+            return StitchGroup(self.color, self.stitches + other.stitches)
+        else:
+            raise TypeError("StitchGroup can only be added to another StitchGroup")
+
+    def __len__(self):
+        # This method allows `len(patch)` and `if patch:
+        return len(self.stitches)
+
+    def add_stitch(self, stitch):
+        self.stitches.append(stitch)
+
+    def reverse(self):
+        return StitchGroup(self.color, self.stitches[::-1])