# ===========================================================================
# eXe 
# Copyright 2004-2006, University of Auckland
# Copyright 2004-2008 eXe Project, http://eXeLearning.org/
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
# ===========================================================================

"""
An RSS Idevice is one built from a RSS feed.
"""

import re

from exe.engine               import feedparser
from exe.engine.idevice       import Idevice
from exe.engine.field         import TextAreaField
from exe.engine.translate     import lateTranslate


# ===========================================================================
class RssIdevice(Idevice):
    """
    An RSS Idevice is one built from a RSS feed.
    """
    def __init__(self):
        Idevice.__init__(self,
                         x_(u"RSS"), 
                         x_(u"Auckland University of Technology"), 
                         x_(u"""The RSS iDevice is used 
to provide new content to an individual users machine. Using this
iDevice you can provide links from a feed you select for learners to view."""), 
                         u"",
                         u"")
        self.emphasis         = Idevice.NoEmphasis
        self.rss              = TextAreaField(x_(u"RSS"))
        self.rss.idevice      = self
        self.icon             = u"inter"
        self._urlInstruc      = x_(u"""Enter an RSS URL for the RSS feed you 
want to attach to your content. Feeds are often identified by a small graphic
 icon (often like this <img src="/images/feed-icon.png" />) or the text "RSS". Clicking on the 
 icon or text label will display an RSS feed right in your browser. You can copy and paste the
URL into this field. Alternately, right clicking on the link or graphic will open a menu box;
click on COPY LINK LOCATION or Copy Shortcut. Back in eXe open the RSS bookmark iDevice and Paste the URL 
into the RSS URL field and click the LOAD button. This will extract the titles from your feed and
display them as links in your content. From here you can edit the bookmarks and add
 instructions or additional learning information.""")
        self.url              = ""
        

        
    # Properties
    urlInstruc      = lateTranslate('urlInstruc')


    def getResourcesField(self, this_resource):
        """
        implement the specific resource finding mechanism for this iDevice:
        """ 
        # be warned that before upgrading, this iDevice field could not exist:
        if hasattr(self, 'rss') and hasattr(self.rss, 'images'):
            for this_image in self.rss.images: 
                if hasattr(this_image, '_imageResource') \
                    and this_resource == this_image._imageResource: 
                        return self.rss

        return None

    def getRichTextFields(self):
        """
        Like getResourcesField(), a general helper to allow nodes to search 
        through all of their fields without having to know the specifics of each
        iDevice type.  
        """
        fields_list = []
        if hasattr(self, 'rss'):
            fields_list.append(self.rss)

        return fields_list


    def loadRss(self, url):
        """
        Load the rss
        """
        content = ""
        try:
            rssDic = feedparser.parse(url)
            length = len(rssDic['entries'])
            if length > 0 :
                for i in range(0, length):
                    content += '<p><A href="%s">%s</A></P>' %(
                        rssDic['entries'][i].link, rssDic['entries'][i].title)          
        except IOError, error:
            log.warning(unicode(error))
            content += _(u"Unable to load RSS feed from %s <br/>Please check the spelling and connection and try again.") % url
            
        if content == "":
            content += _(u"Unable to load RSS feed from %s <br/>Please check the spelling and connection and try again.") % url
        self.rss.content = unicode(content)
        # now that these are supporting images, any direct manipulation
        # of the content field must also store this updated information
        # into the other corresponding fields of TextAreaField:
        # (perhaps eventually a property should be made for TextAreaField 
        #  such that these extra set's are not necessary, but for now, here:)
        self.rss.content_w_resourcePaths = self.rss.content
        self.rss.content_wo_resourcePaths = self.rss.content

    def burstHTML(self, i):
        """
        takes a BeautifulSoup fragment (i) and bursts its contents to 
        import this idevice from a CommonCartridge export
        """
        # RSS Idevice:
        # option title for RSS, with mode emphasis:
        title = i.find(name='span', attrs={'class' : 'iDeviceTitle' })
        if title is not None: 
            self.title = title.renderContents().decode('utf-8')
            self.emphasis=Idevice.SomeEmphasis

        rss = i.find(name='div', attrs={'id' : re.compile('^ta') })
        self.rss.content_wo_resourcePaths = rss.renderContents().decode('utf-8')
        # and add the LOCAL resource paths back in:
        self.rss.content_w_resourcePaths = \
                self.rss.MassageResourceDirsIntoContent( \
                    self.rss.content_wo_resourcePaths)
        self.rss.content = self.rss.content_w_resourcePaths

        # WARNING: the following COULD crash on accented characters, eg:
        #  'ascii' codec can't encode character u'\xe8' in 
        #  position 11: ordinal not in range(128)
        url = i.find(name='div', attrs={'class' : 'rss_url' })
        if url is not None: 
            self.url = url.attrMap['value'].decode('utf-8')


# ===========================================================================