Sort recipes by main (first) category into sections

This allows to sensibly group multiple recipes in a book, and to
enable a structured table-of-content.

The first category, in the absence of a better mechanism, is treated
specially to primarily group recipes.  It is the first sorting
criteria and primary ToC entries are generated per first category.
The recipe name remains the secondary sorting criterion.

Fixes thinkle#57.

Signed-off-by: Martin Pohlack <[email protected]>

gourmet/plugins/import_export/epub_plugin/epub_exporter.py

@@ -54,6 +54,8 @@ def __init__(self, outFileName):
 
         # This adds the field also known as keywords in some programs.
         self.ebook.add_metadata('DC', 'subject', "cooking")
+        self.prev_category = None
+        self.current_section = None
 
     def addRecipeCssFromFile(self, filename):
         """ Adds the CSS file from filename to the book. The style will be added
@@ -94,7 +96,13 @@ def getFileForRecipeID(self, id, ext=".xhtml"):
         """
         return "recipe_%i%s" % (id,ext)
 
-    def addRecipeText(self, uniqueId, title, text):
+    def flush_toc_section(self):
+        if self.current_section:
+            self.toc.append( (epub.Section(self.prev_category),
+                              self.current_section) )
+            self.current_section = None
+
+    def addRecipeText(self, uniqueId, title, text, first_cat=None):
         """ Adds the recipe text as a chapter.
         """
         uniqueName = self.getFileForRecipeID(uniqueId, ext="")
@@ -108,13 +116,21 @@ def addRecipeText(self, uniqueId, title, text):
         # add chapter
         self.ebook.add_item(c1)
         self.spine.append(c1)
-
-        # define Table Of Contents
-        self.toc.append( epub.Link(fileName, title, uniqueName) )
+        l = epub.Link(fileName, title, uniqueName)
+
+        # Define Table Of Contents.  Collect entries per section and
+        # flush on section change.
+        if self.prev_category is None or (first_cat != self.prev_category and first_cat is not None):
+            self.flush_toc_section()
+            self.prev_category = first_cat
+            self.current_section = [l]
+        else:
+            self.current_section.append(l)
 
     def finish(self):
         """ Finish the book and writes it to the disk.
         """
+        self.flush_toc_section()
         self.ebook.toc = self.toc
 
         # add default NCX and Nav file
@@ -264,7 +280,12 @@ def write_foot (self):
         self.preparedDocument.append(RECIPE_FOOT)
 
         self._grab_attr_(self.r,'id')
-        self.doc.addRecipeText(self._grab_attr_(self.r,'id'), self.get_title(), "".join(self.preparedDocument) )
+        cats = self.rd.get_cats(self.r)
+        first_cat = None
+        if cats:
+            first_cat = cats[0]
+        self.doc.addRecipeText(self._grab_attr_(self.r,'id'), self.get_title(), "".join(self.preparedDocument),
+                               first_cat=first_cat)
 
 class website_exporter (ExporterMultirec):
     def __init__ (self, rd, recipe_table, out, conv=None, ext='epub', copy_css=True,
@@ -285,13 +306,25 @@ def __init__ (self, rd, recipe_table, out, conv=None, ext='epub', copy_css=True,
 
         if conv:
             self.exportargs['conv']=conv
+
+        # Sort by first category first so we can build chapters in the
+        # book, secondary by name.
+        recipe_table.sort(key = lambda x: (self._get_first_category(x, rd), x.title))
         ExporterMultirec.__init__(self, rd, recipe_table, out,
                                   one_file=True,
                                   create_file=False,
                                   ext=self.ext,
                                   exporter=epub_exporter,
                                   exporter_kwargs=self.exportargs)
 
+    @staticmethod
+    def _get_first_category(r, rd):
+        cats = rd.get_cats(r)
+        if cats:
+            return cats[0]
+        else:
+            return None
+
     def recipe_hook (self, rec, filename, exporter):
         """Add index entry"""
         # TODO: Do some cool things here.