add support for section and figure numbers (useblocks#93)

fixes: useblocks#27

setup.py

@@ -24,6 +24,7 @@
               'sphinx_simplepdf.builders',
               'sphinx_simplepdf.directives',
               'sphinx_simplepdf.themes/simplepdf_theme',
+              'sphinx_simplepdf.writers',
               ],
     package_data={'sphinx_simplepdf/themes/simplepdf_theme': [
         'theme.conf',

sphinx_simplepdf/builders/simplepdf.py

@@ -18,6 +18,8 @@
 
 from sphinx.util import logging
 
+from sphinx_simplepdf.writers.simplepdf import SimplepdfTranslator
+
 logger = logging.getLogger(__name__)
 
 
@@ -27,6 +29,8 @@ class SimplePdfBuilder(SingleFileHTMLBuilder):
     file_suffix = ".pdf"
     links_suffix = None
 
+    default_translator_class = SimplepdfTranslator
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         if self.app.config.simplepdf_theme is not None:

sphinx_simplepdf/writers/simplepdf.py

@@ -0,0 +1,64 @@
+import logging
+
+from docutils import nodes
+from docutils.nodes import Element
+from sphinx.locale import __
+from sphinx.writers.html5 import HTML5Translator
+
+logger = logging.getLogger(__name__)
+
+
+class SimplepdfTranslator(HTML5Translator):
+
+    def get_secnumber(self, node: Element) -> tuple[int, ...] | None:
+        if node.get('secnumber'):
+            return node['secnumber']
+
+        if isinstance(node.parent, nodes.section):
+            docname = self.docnames[-1]
+            anchorname = "{}/#{}".format(docname, node.parent['ids'][0])
+            if anchorname not in self.builder.secnumbers:
+                anchorname = "%s/" % docname  # try first heading which has no anchor
+
+            if self.builder.secnumbers.get(anchorname):
+                return self.builder.secnumbers[anchorname]
+
+        return None
+
+    def add_secnumber(self, node: Element) -> None:
+        secnumber = self.get_secnumber(node)
+        if secnumber:
+            self.body.append('<span class="section-number">')
+            self.body.append('.'.join(map(str, secnumber)) + self.secnumber_suffix)
+            self.body.append('</span>')
+
+    def get_fignumber(self, node: Element) -> str | None:
+        figtype = self.builder.env.domains['std'].get_enumerable_node_type(node)
+        if not figtype:
+            return None
+
+        if len(node['ids']) == 0:
+            msg = __('Any IDs not assigned for %s node') % node.tagname
+            logger.warning(msg, location=node)
+            return None
+
+        key = f"{self.docnames[-1]}/{figtype}"
+        figure_id = node['ids'][0]
+        if figure_id not in self.builder.fignumbers.get(key, {}):
+            return None
+
+        prefix = self.config.numfig_format.get(figtype)
+        if prefix is None:
+            msg = __('numfig_format is not defined for %s') % figtype
+            logger.warning(msg)
+            return None
+
+        numbers = self.builder.fignumbers[key][figure_id]
+        return prefix % '.'.join(map(str, numbers))
+
+    def add_fignumber(self, node: Element) -> None:
+        fignumber = self.get_fignumber(node)
+        if fignumber:
+            self.body.append('<span class="caption-number">')
+            self.body.append(fignumber + ' ')
+            self.body.append('</span>')