"""
Sphinx plugins for Django documentation.
"""

import docutils.nodes
import docutils.transforms
import sphinx
import sphinx.addnodes
import sphinx.builder
import sphinx.directives
import sphinx.environment
import sphinx.htmlwriter

def setup(app):
    app.add_crossref_type(
        directivename = "setting",
        rolename      = "setting",
        indextemplate = "pair: %s; setting",
    )
    app.add_crossref_type(
        directivename = "templatetag",
        rolename      = "ttag",
        indextemplate = "pair: %s; template tag"
    )
    app.add_crossref_type(
        directivename = "templatefilter",
        rolename      = "tfilter",
        indextemplate = "pair: %s; template filter"
    )
    app.add_crossref_type(
        directivename = "fieldlookup",
        rolename      = "lookup",
        indextemplate = "pair: %s, field lookup type",
    )
    app.add_description_unit(
        directivename = "django-admin",
        rolename      = "djadmin",
        indextemplate = "pair: %s; django-admin command",
        parse_node    = parse_django_admin_node,
    )
    app.add_description_unit(
        directivename = "django-admin-option",
        rolename      = "djadminopt",
        indextemplate = "pair: %s; django-admin command-line option",
        parse_node    = lambda env, sig, signode: sphinx.directives.parse_option_desc(signode, sig),
    )
    app.add_transform(SuppressBlockquotes)
    
    # Monkeypatch PickleHTMLBuilder so that it doesn't die in Sphinx 0.4.2
    if sphinx.__version__ == '0.4.2':
        monkeypatch_pickle_builder()
                
class SuppressBlockquotes(docutils.transforms.Transform):
    """
    Remove the default blockquotes that encase indented list, tables, etc.
    """
    default_priority = 300
    
    suppress_blockquote_child_nodes = (
        docutils.nodes.bullet_list, 
        docutils.nodes.enumerated_list, 
        docutils.nodes.definition_list,
        docutils.nodes.literal_block, 
        docutils.nodes.doctest_block, 
        docutils.nodes.line_block, 
        docutils.nodes.table
    )
    
    def apply(self):
        for node in self.document.traverse(docutils.nodes.block_quote):
            if len(node.children) == 1 and isinstance(node.children[0], self.suppress_blockquote_child_nodes):
                node.replace_self(node.children[0])

class DjangoHTMLTranslator(sphinx.htmlwriter.SmartyPantsHTMLTranslator):
    """
    Django-specific reST to HTML tweaks.
    """

    # Don't use border=1, which docutils does by default.
    def visit_table(self, node):
        self.body.append(self.starttag(node, 'table', CLASS='docutils'))
        
    # Give each section a unique ID -- nice for custom CSS hooks
    # This is different on docutils 0.5 vs. 0.4...
    
    # The docutils 0.4 override.
    if hasattr(sphinx.htmlwriter.SmartyPantsHTMLTranslator, 'start_tag_with_title'):
        def start_tag_with_title(self, node, tagname, **atts):
            node = {
                'classes': node.get('classes', []), 
                'ids': ['s-%s' % i for i in node.get('ids', [])]
            }
            return self.starttag(node, tagname, **atts)
            
    # The docutils 0.5 override.
    else:        
        def visit_section(self, node):
            old_ids = node.get('ids', [])
            node['ids'] = ['s-' + i for i in old_ids]
            sphinx.htmlwriter.SmartyPantsHTMLTranslator.visit_section(self, node)
            node['ids'] = old_ids

def parse_django_admin_node(env, sig, signode):
    command = sig.split(' ')[0]
    env._django_curr_admin_command = command
    title = "django-admin.py %s" % sig
    signode += sphinx.addnodes.desc_name(title, title)
    return sig

def monkeypatch_pickle_builder():
    import shutil
    from os import path
    try:
        import cPickle as pickle
    except ImportError:
        import pickle
    from sphinx.util.console import bold
    
    def handle_finish(self):
        # dump the global context
        outfilename = path.join(self.outdir, 'globalcontext.pickle')
        f = open(outfilename, 'wb')
        try:
            pickle.dump(self.globalcontext, f, 2)
        finally:
            f.close()

        self.info(bold('dumping search index...'))
        self.indexer.prune(self.env.all_docs)
        f = open(path.join(self.outdir, 'searchindex.pickle'), 'wb')
        try:
            self.indexer.dump(f, 'pickle')
        finally:
            f.close()

        # copy the environment file from the doctree dir to the output dir
        # as needed by the web app
        shutil.copyfile(path.join(self.doctreedir, sphinx.builder.ENV_PICKLE_FILENAME),
                        path.join(self.outdir, sphinx.builder.ENV_PICKLE_FILENAME))

        # touch 'last build' file, used by the web application to determine
        # when to reload its environment and clear the cache
        open(path.join(self.outdir, sphinx.builder.LAST_BUILD_FILENAME), 'w').close()

    sphinx.builder.PickleHTMLBuilder.handle_finish = handle_finish