# -*- coding: utf-8 -*-
"""
Contains classes and utilities related to hyde urls.
"""
from hyde.plugin import Plugin
from hyde.site import Site

from functools import wraps
from fswrap import File


class UrlCleanerPlugin(Plugin):

    """
    Url Cleaner plugin for hyde. Adds to hyde the ability to generate clean
    urls.

    Configuration example
    ---------------------
    #yaml
    urlcleaner:
        index_file_names:
            # Identifies the files that represents a directory listing.
            # These file names are automatically stripped away when
            # the content_url function is called.
            - index.html
        strip_extensions:
            # The following extensions are automatically removed when
            # generating the urls using content_url function.
            - html
        # This option will append a slash to the end of directory paths
        append_slash: true
    """

    def __init__(self, site):
        super(UrlCleanerPlugin, self).__init__(site)

    def begin_site(self):
        """
        Replace the content_url method in the site object with a custom method
        that cleans urls based on the given configuration.
        """
        config = self.site.config

        if not hasattr(config, 'urlcleaner'):
            return

        if (hasattr(Site, '___url_cleaner_patched___')):
            return

        settings = config.urlcleaner

        def clean_url(urlgetter):
            @wraps(urlgetter)
            def wrapper(site, path, safe=None):
                url = urlgetter(site, path, safe)
                index_file_names = getattr(settings,
                                           'index_file_names',
                                           ['index.html'])
                rep = File(url)
                if rep.name in index_file_names:
                    url = rep.parent.path.rstrip('/')
                    if hasattr(settings, 'append_slash') and \
                            settings.append_slash:
                        url += '/'
                elif hasattr(settings, 'strip_extensions'):
                    if rep.kind in settings.strip_extensions:
                        url = rep.parent.child(rep.name_without_extension)
                return url or '/'
            return wrapper

        Site.___url_cleaner_patched___ = True
        Site.content_url = clean_url(Site.content_url)