~azzar1/unity/add-show-desktop-key

# IVLE - Informatics Virtual Learning Environment

# Copyright (C) 2007-2009 The University of Melbourne

#

# 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., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

# Author: Nick Chadwick

import inspect

import os.path

import urllib

import genshi.template

from ivle.webapp.media import media_url

from ivle.webapp.core import Plugin as CorePlugin

from ivle.webapp.base.views import BaseView

from ivle.webapp.base.plugins import ViewPlugin, OverlayPlugin

from ivle.webapp.errors import HTTPError, Unauthorized

import ivle.conf

import ivle.util

class XHTMLView(BaseView):

    """

    A view which provides a base class for views which need to return XHTML

    It is expected that apps which use this view will be written using Genshi

    templates.

    """

    template = 'template.html'

    plugin_scripts = {}

    plugin_styles = {}

    overlay_blacklist = []

    def __init__(self, req, **kwargs):

        for key in kwargs:

            setattr(self, key, kwargs[key])

    def render(self, req):

        req.content_type = 'text/html' # TODO: Detect application/xhtml+xml

        # View template

        viewctx = genshi.template.Context()

        self.populate(req, viewctx)

        # The template is found in the directory of the module containing the

        # view.

        app_template = os.path.join(os.path.dirname(

                        inspect.getmodule(self).__file__), self.template) 

        req.write_html_head_foot = False

        loader = genshi.template.TemplateLoader(".", auto_reload=True)

        tmpl = loader.load(app_template)

        app = tmpl.generate(viewctx)

        for plugin in self.plugin_scripts:

            for path in self.plugin_scripts[plugin]:

                req.scripts.append(media_url(req, plugin, path))

        for plugin in self.plugin_styles:

            for path in self.plugin_styles[plugin]:

                req.styles.append(media_url(req, plugin, path))

        # Global template

        ctx = genshi.template.Context()

        # XXX: Leave this here!! (Before req.styles is read)

        ctx['overlays'] = self.render_overlays(req)

        ctx['styles'] = [media_url(req, CorePlugin, 'ivle.css')]

        ctx['styles'] += req.styles

        ctx['scripts'] = [media_url(req, CorePlugin, path) for path in

                           ('util.js', 'json2.js', 'md5.js')]

        ctx['scripts'] += req.scripts

        ctx['scripts_init'] = req.scripts_init

        ctx['app_template'] = app

        self.populate_headings(req, ctx)

        tmpl = loader.load(os.path.join(os.path.dirname(__file__), 

                                                        'ivle-headings.html'))

        req.write(tmpl.generate(ctx).render('xhtml', doctype='xhtml'))

    def populate(self, req, ctx):

        raise NotImplementedError()

    def populate_headings(self, req, ctx):

        ctx['favicon'] = None

        ctx['root_dir'] = ivle.conf.root_dir

        ctx['public_host'] = ivle.conf.public_host

        ctx['write_javascript_settings'] = req.write_javascript_settings

        if req.user:

            ctx['login'] = req.user.login

            ctx['logged_in'] = True

            ctx['nick'] = req.user.nick

        else:

            ctx['login'] = None

            ctx['logged_in'] = False

        ctx['publicmode'] = req.publicmode

        if hasattr(self, 'help'):

            ctx['help_path'] = self.help

        ctx['apps_in_tabs'] = []

        for plugin in req.plugin_index[ViewPlugin]:

            if not hasattr(plugin, 'tabs'):

                continue

            for tab in plugin.tabs:

                # tab is a tuple: name, title, desc, icon, path

                new_app = {}

                new_app['this_app'] = hasattr(self, 'appname') \

                                      and tab[0] == self.appname

                # Icon name

                if tab[3] is not None:

                    new_app['has_icon'] = True

                    icon_url = media_url(req, plugin, tab[3])

                    new_app['icon_url'] = icon_url

                    if new_app['this_app']:

                        ctx['favicon'] = icon_url

                else:

                    new_app['has_icon'] = False

                new_app['path'] = ivle.util.make_path(tab[4])

                new_app['desc'] = tab[2]

                new_app['name'] = tab[1]

                new_app['weight'] = tab[5]

                ctx['apps_in_tabs'].append(new_app)

        ctx['apps_in_tabs'].sort(key=lambda tab: tab['weight'])

    def render_overlays(self, req):

        """Generate XML streams for the overlays.

        Returns a list of streams. Populates the scripts, styles, and 

        scripts_init.

        """

        overlays = []

        for plugin in req.plugin_index[OverlayPlugin]:

            for overclass in plugin.overlays:

                if overclass in self.overlay_blacklist:

                    continue

                overlay = overclass(req)

                #TODO: Re-factor this to look nicer

                for mplugin in overlay.plugin_scripts:

                    for path in overlay.plugin_scripts[mplugin]:

                        req.scripts.append(media_url(req, mplugin, path))

                for mplugin in overlay.plugin_styles:

                    for path in overlay.plugin_styles[mplugin]:

                        req.styles.append(media_url(req, mplugin, path))

                req.scripts_init += overlay.plugin_scripts_init

                overlays.append(overlay.render(req))

        return overlays

    @classmethod

    def get_error_view(cls, e):

        view_map = {HTTPError:    XHTMLErrorView,

                    Unauthorized: XHTMLUnauthorizedView}

        for exccls in inspect.getmro(type(e)):

            if exccls in view_map:

                return view_map[exccls]

class XHTMLErrorView(XHTMLView):

    template = 'xhtmlerror.html'

    def __init__(self, req, exception):

        self.context = exception

    def populate(self, req, ctx):

        ctx['exception'] = self.context

class XHTMLUnauthorizedView(XHTMLErrorView):

    template = 'xhtmlunauthorized.html'

    def __init__(self, req, exception):

        super(XHTMLUnauthorizedView, self).__init__(req, exception)

        if req.user is None:

            # Not logged in. Redirect to login page.

            req.throw_redirect('/+login?' + 

                               urllib.urlencode([('url', req.uri)]))

        req.status = 403