Initial import

ebook_converter/ebooks/lrf/pylrs/pylrfopt.py

@@ -0,0 +1,44 @@
+from __future__ import absolute_import, division, print_function, unicode_literals
+
+
+def _optimize(tagList, tagName, conversion):
+    # copy the tag of interest plus any text
+    newTagList = []
+    for tag in tagList:
+        if tag.name == tagName or tag.name == "rawtext":
+            newTagList.append(tag)
+
+    # now, eliminate any duplicates (leaving the last one)
+    for i, newTag in enumerate(newTagList[:-1]):
+        if newTag.name == tagName and newTagList[i+1].name == tagName:
+            tagList.remove(newTag)
+
+    # eliminate redundant settings to same value across text strings
+    newTagList = []
+    for tag in tagList:
+        if tag.name == tagName:
+            newTagList.append(tag)
+
+    for i, newTag in enumerate(newTagList[:-1]):
+        value = conversion(newTag.parameter)
+        nextValue = conversion(newTagList[i+1].parameter)
+        if value == nextValue:
+            tagList.remove(newTagList[i+1])
+
+    # eliminate any setting that don't have text after them
+    while len(tagList) > 0 and tagList[-1].name == tagName:
+        del tagList[-1]
+
+
+def tagListOptimizer(tagList):
+    # this function eliminates redundant or unnecessary tags
+    # it scans a list of tags, looking for text settings that are
+    # changed before any text is output
+    # for example,
+    #  fontsize=100, fontsize=200, text, fontsize=100, fontsize=200
+    # should be:
+    # fontsize=200 text
+    oldSize = len(tagList)
+    _optimize(tagList, "fontsize", int)
+    _optimize(tagList, "fontweight", int)
+    return oldSize - len(tagList)