1 files changed, 95 insertions, 0 deletions
diff --git a/lib/threads/catalog.py b/lib/threads/catalog.py
new file mode 100644
index 00000000..cebae4ff
--- /dev/null
+++ b/lib/threads/catalog.py
@@ -0,0 +1,95 @@
+import os
+from os.path import dirname, realpath
+import sys
+from glob import glob
+from collections import Sequence
+from .palette import ThreadPalette
+
+class _ThreadCatalog(Sequence):
+    """Holds a set of ThreadPalettes."""
+
+    def __init__(self):
+        self.palettes = []
+        self.load_palettes(self.get_palettes_path())
+
+    def get_palettes_path(self):
+        if getattr(sys, 'frozen', None) is not None:
+            path = os.path.join(sys._MEIPASS, "..")
+        else:
+            path = dirname(dirname(dirname(realpath(__file__))))
+
+        return os.path.join(path, 'palettes')
+
+    def load_palettes(self, path):
+        for palette_file in glob(os.path.join(path, '*.gpl')):
+            self.palettes.append(ThreadPalette(palette_file))
+
+    def palette_names(self):
+        return list(sorted(palette.name for palette in self))
+
+    def __getitem__(self, item):
+        return self.palettes[item]
+
+    def __len__(self):
+        return len(self.palettes)
+
+    def _num_exact_color_matches(self, palette, threads):
+        """Number of colors in stitch plan with an exact match in this palette."""
+
+        return sum(1 for thread in threads if thread in palette)
+
+    def match_and_apply_palette(self, stitch_plan, palette=None):
+        if palette is None:
+            palette = self.match_palette(stitch_plan)
+        else:
+            palette = self.get_palette_by_name(palette)
+
+        if palette is not None:
+            self.apply_palette(stitch_plan, palette)
+
+        return palette
+
+    def match_palette(self, stitch_plan):
+        """Figure out which color palette was used
+
+        Scans the catalog of color palettes and chooses one that seems most
+        likely to be the one that the user used.  A palette will only be
+        chosen if more tha 80% of the thread colors in the stitch plan are
+        exact matches for threads in the palette.
+        """
+
+        threads = [color_block.color for color_block in stitch_plan]
+        palettes_and_matches = [(palette, self._num_exact_color_matches(palette, threads))
+                                for palette in self]
+        palette, matches = max(palettes_and_matches, key=lambda item: item[1])
+
+        if matches < 0.8 * len(stitch_plan):
+            # if less than 80% of the colors are an exact match,
+            # don't use this palette
+            return None
+        else:
+            return palette
+
+    def apply_palette(self, stitch_plan, palette):
+        for color_block in stitch_plan:
+            nearest = palette.nearest_color(color_block.color)
+
+            color_block.color.name = nearest.name
+            color_block.color.number = nearest.number
+            color_block.color.manufacturer = nearest.manufacturer
+
+    def get_palette_by_name(self, name):
+        for palette in self:
+            if palette.name == name:
+                return palette
+
+_catalog = None
+
+def ThreadCatalog():
+    """Singleton _ThreadCatalog factory"""
+
+    global _catalog
+    if _catalog is None:
+        _catalog = _ThreadCatalog()
+
+    return _catalog