#!/usr/bin/python
# -*- coding: utf-8 -*-

# Libervia: a Salut à Toi frontend
# Copyright (C) 2011, 2012, 2013, 2014, 2015 Jérôme Poisson <goffi@goffi.org>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.i18n import _, D_
from sat_frontends.tools.strings import addURLToText
from sat.core.log import getLogger
log = getLogger(__name__)

from twisted.internet import defer
from twisted.web import server
from twisted.web.resource import Resource
from twisted.words.protocols.jabber.jid import JID
from datetime import datetime
from sys import path
import importlib
import uuid
import re
import os

from libervia.server.html_tools import sanitizeHtml, convertNewLinesToXHTML
from libervia.server.constants import Const as C


class TemplateProcessor(object):

    THEME = 'default'

    def __init__(self, host):
        self.host = host

        # add Libervia's themes directory to the python path
        path.append(os.path.dirname(self.host.themes_dir))

    def useTemplate(self, request, tpl, data=None):
        root_url = '../' * len(request.postpath)
        theme_url = os.path.join(root_url, 'themes', self.THEME)

        # import the theme module
        themes = os.path.basename(os.path.dirname(os.path.dirname(self.host.themes_dir)))
        theme = importlib.import_module("%s.templates" % self.THEME, themes)
        data_ = {'theme': theme_url,
                 'images': os.path.join(theme_url, 'images'),
                 'styles': os.path.join(theme_url, 'styles'),
                 }
        if data:
            data_.update(data)
        return (getattr(theme, tpl.upper()).format(**data_)).encode('utf-8')


class MicroBlog(Resource, TemplateProcessor):
    isLeaf = True

    def __init__(self, host):
        self.host = host
        Resource.__init__(self)
        TemplateProcessor.__init__(self, host)
        self.host.bridge.register('entityDataUpdated', self.entityDataUpdatedCb)
        self.host.bridge.register('actionResult', self.actionResultCb)  # FIXME: actionResult is to be removed
        self.avatars_cache = {}
        self.waiting_deferreds = {}

    def entityDataUpdatedCb(self, entity_jid_s, key, value, dummy):
        """Retrieve the avatar we've been waiting for and fires the callback
        for self.getAvatar to return.

        @param entity_jid_s (str): JID of the contact
        @param key (str): entity data key
        @param value (str): entity data value
        @param dummy (str): that would be C.SERVICE_PROFILE
        """
        if key != 'avatar':
            return
        entity_jid_s = entity_jid_s.lower()
        log.debug(_(u"Received a new avatar for entity %s") % entity_jid_s)
        avatar = C.AVATARS_DIR + value
        self.avatars_cache[entity_jid_s] = avatar
        try:
            self.waiting_deferreds[entity_jid_s][1].callback(avatar)
            del self.waiting_deferreds[entity_jid_s]
        except KeyError:
            pass

    def actionResultCb(self, answer_type, action_id, data, dummy):
        """Fires the callback for self.getAvatar to return

        @param answer_type (str): 'SUPPRESS' or another value that we would ignore
        @param action_id (str): the request ID
        @param data (dict): ignored
        @param dummy (str): that would be C.SERVICE_PROFILE
        """
        # FIXME: actionResult is to be removed. For now we use it to get notified
        # when the requested vCard hasn't been found. Replace with the new system.
        if answer_type != 'SUPPRESS':
            return
        try:
            entity_jid_s = [key for (key, value) in self.waiting_deferreds.items() if value[0] == action_id][0]
        except IndexError:  # impossible to guess the entity
            return
        log.debug(_(u"Using default avatar for entity %s") % entity_jid_s)
        self.avatars_cache[entity_jid_s] = C.DEFAULT_AVATAR_URL
        self.waiting_deferreds[entity_jid_s][1].callback(C.DEFAULT_AVATAR_URL)
        del self.waiting_deferreds[entity_jid_s]

    def getAvatar(self, profile):
        """Get the avatar of the given profile

        @param profile(unicode): %(doc_profile)s
        @return: deferred avatar path, relative to the server's root
        """
        jid_s = (profile + '@' + self.host.bridge.getNewAccountDomain()).lower()
        if jid_s in self.avatars_cache:
            return defer.succeed(self.avatars_cache[jid_s])
        # FIXME: request_id is no more need when actionResult is removed
        request_id = self.host.bridge.getCard(jid_s, C.SERVICE_PROFILE)
        self.waiting_deferreds[jid_s] = (request_id, defer.Deferred())
        return self.waiting_deferreds[jid_s][1]

    def render_GET(self, request):
        if not request.postpath:
            return self.useTemplate(request, "error", {'message': "You must indicate a nickname"})

        prof_requested = request.postpath[0]
        #TODO: char check: only use alphanumerical chars + some extra(_,-,...) here
        prof_found = self.host.bridge.getProfileName(prof_requested)
        if not prof_found or prof_found == C.SERVICE_PROFILE:
            return self.useTemplate(request, "error", {'message': "Invalid nickname"})

        d = defer.Deferred()
        JID(self.host.bridge.asyncGetParamA('JabberID', 'Connection', 'value', C.SERVER_SECURITY_LIMIT, prof_found, callback=d.callback, errback=d.errback))
        d.addCallbacks(lambda pub_jid_s: self.gotJID(pub_jid_s, request, prof_found))
        return server.NOT_DONE_YET

    def gotJID(self, pub_jid_s, request, profile):
        pub_jid = JID(pub_jid_s)
        d = defer.Deferred()
        item_id = None
        atom = None

        if len(request.postpath) > 1:
            if request.postpath[1] == 'atom.xml':  # return the atom feed
                atom = True
            else:
                try:  # check if the given path is a valid UUID
                    uuid.UUID(request.postpath[1])
                    item_id = request.postpath[1]
                except ValueError:
                    pass

        rsm_ = self.parseURLParams(request, item_id)
        max_items = int(rsm_['max'])

        if atom is not None:
            d.addCallbacks(self.render_atom_feed, self.render_error_blog, [request], None, [request, profile], None)
            self.host.bridge.getGroupBlogsAtom(pub_jid.userhost(), rsm_, C.SERVICE_PROFILE, d.callback, d.errback)
            return

        d.addCallbacks(self.render_html_blog, self.render_error_blog, [request, profile], None, [request, profile], None)
        if item_id:
            if max_items > 0:  # display one message and its comments
                self.host.bridge.getGroupBlogsWithComments(pub_jid.userhost(), [item_id], {}, max_items, C.SERVICE_PROFILE, d.callback, d.errback)
            else:  # display one message, count its comments
                self.host.bridge.getGroupBlogs(pub_jid.userhost(), [item_id], {}, True, C.SERVICE_PROFILE, d.callback, d.errback)
        else:
            if max_items == 1:  # display one message and its comments
                self.host.bridge.getGroupBlogsWithComments(pub_jid.userhost(), [], rsm_, C.RSM_MAX_COMMENTS, C.SERVICE_PROFILE, d.callback, d.errback)
            else:  # display the last messages, count their comments
                self.host.bridge.getGroupBlogs(pub_jid.userhost(), [], rsm_, True, C.SERVICE_PROFILE, d.callback, d.errback)

    def parseURLParams(self, request, item_id):
        # retrieve RSM request data from URL parameters
        rsm_ = {}
        try:
            rsm_['max'] = request.args['max'][0]
        except (ValueError, KeyError):
            rsm_['max'] = unicode(C.RSM_MAX_ITEMS if item_id else C.RSM_MAX_COMMENTS)
        try:
            rsm_['index'] = request.args['index'][0]
        except (ValueError, KeyError):
            try:
                rsm_['before'] = request.args['before'][0]
            except KeyError:
                try:
                    rsm_['after'] = request.args['after'][0]
                except KeyError:
                    pass
        return rsm_

    def render_html_blog(self, mblog_data, request, profile):
        """Retrieve the user parameters before actually rendering the static blog

        @param mblog_data (list): couple (list, dict) with:
            - a list of microblog data, or a list of couple containing:
                - microblog data (main item)
                - couple (comments data, RSM response data for the comments)
            - RSM response data for the main items
        @param request: HTTP request
        @param profile
        """
        d_list = []
        options = {}

        def getCallback(param_name):
            d = defer.Deferred()
            d.addCallback(lambda value: options.update({param_name: value}))
            d_list.append(d)
            return d.callback

        eb = lambda failure: self.render_error_blog(failure, request, profile)

        self.getAvatar(profile).addCallbacks(getCallback('avatar'), eb)
        for param_name in (C.STATIC_BLOG_PARAM_TITLE, C.STATIC_BLOG_PARAM_BANNER, C.STATIC_BLOG_PARAM_KEYWORDS, C.STATIC_BLOG_PARAM_DESCRIPTION):
            self.host.bridge.asyncGetParamA(param_name, C.STATIC_BLOG_KEY, 'value', C.SERVER_SECURITY_LIMIT, profile, callback=getCallback(param_name), errback=eb)

        cb = lambda dummy: self.__render_html_blog(mblog_data, options, request, profile)
        defer.DeferredList(d_list).addCallback(cb)

    def __render_html_blog(self, mblog_data, options, request, profile):
        """Actually render the static blog. If mblog_data is a list of dict, we are missing
        the comments items so we just display the main items. If mblog_data is a list of couple,
        each couple is associating a main item data with the list of its comments, so we render all.

        @param mblog_data (list): couple (list, dict) with:
            - a list of microblog data, or a list of couple containing:
                - microblog data (main item)
                - couple (comments data, RSM response data for the comments)
            - RSM response data for the main items
        @param options: dict defining the blog's parameters
        @param request: the HTTP request
        @profile
        """
        if not isinstance(options, dict):
            options = {}
        user = sanitizeHtml(profile).encode('utf-8')
        root_url = '../' * len(request.postpath)
        base_url = root_url + 'blog/' + user

        def getOption(key):
            return sanitizeHtml(options[key]).encode('utf-8') if key in options else ''

        def getImageOption(key, default, alt):
            """regexp from http://answers.oreilly.com/topic/280-how-to-validate-urls-with-regular-expressions/"""
            url = options[key].encode('utf-8') if key in options else ''
            regexp = r"^(https?|ftp)://[a-z0-9-]+(\.[a-z0-9-]+)+(/[\w-]+)*/[\w-]+\.(gif|png|jpg)$"
            if re.match(regexp, url):
                url = url
                suffix = "<br/>"
            else:
                url = default
                suffix = ""
            return self.useTemplate(request, "banner", {'alt': alt, 'url': url, 'suffix': suffix})

        avatar = os.path.normpath(root_url + getOption('avatar'))
        title = getOption(C.STATIC_BLOG_PARAM_TITLE) or user
        data = {'base_url': base_url,
                'user': user,
                'keywords': getOption(C.STATIC_BLOG_PARAM_KEYWORDS),
                'description': getOption(C.STATIC_BLOG_PARAM_DESCRIPTION),
                'title': getOption(C.STATIC_BLOG_PARAM_TITLE) or "%s's microblog" % user,
                'favicon': avatar,
                'banner_elt': getImageOption(C.STATIC_BLOG_PARAM_BANNER, avatar, title),
                'title_elt': title,
                }

        mblog_data, main_rsm = mblog_data
        mblog_data = [(entry if isinstance(entry, tuple) else (entry, ([], {}))) for entry in mblog_data]
        mblog_data = sorted(mblog_data, key=lambda entry: (-float(entry[0].get('updated', 0))))

        data.update(self.getNavigationLinks(request, mblog_data, main_rsm, base_url))
        request.write(self.useTemplate(request, 'header', data))

        BlogMessages(self.host, request, base_url, mblog_data).render()

        request.write(self.useTemplate(request, "footer", data))
        request.finish()

    def getNavigationLinks(self, request, mblog_data, rsm_data, base_url):
        """Build the navigation links.

        @param mblog_data (dict): the microblogs that are displayed on the page
        @param rsm_data (dict): rsm data
        @param base_url (unicode): the base URL for this user's blog
        @return: dict
        """
        data = {}
        for key in ('later_message', 'later_messages', 'older_message', 'older_messages'):
            count = int(rsm_data.get('count', 0))
            display_single = len(mblog_data) == 1
            data[key] = ''  # key must exist when using the template
            if count <= 0 or (display_single == key.endswith('s')):
                continue

            index = int(rsm_data['index'])

            link_data = {'base_url': base_url, 'suffix': ''}

            if key.startswith('later_message'):
                if index <= 0:
                    continue
                link_data['item_id'] = rsm_data['first']
                link_data['post_arg'] = 'before'
            else:
                if index + len(mblog_data) >= count:
                    continue
                link_data['item_id'] = rsm_data['last']
                link_data['post_arg'] = 'after'

            if display_single:
                link_data['suffix'] = '&max=1'

            link = "%(base_url)s?%(post_arg)s=%(item_id)s%(suffix)s" % link_data

            link_data = {'link': link, 'class': key, 'text': key.replace('_', ' ')}
            data[key] = (self.useTemplate(request, 'nav_link', link_data)).encode('utf-8')

        return data

    def render_atom_feed(self, feed, request):
        request.write(feed.encode('utf-8'))
        request.finish()

    def render_error_blog(self, error, request, profile):
        request.write(self.useTemplate(request, "error", {'message': "Can't access requested data"}))
        request.finish()


class BlogMessages(TemplateProcessor):

    def __init__(self, host, request, base_url, mblog_data):
        TemplateProcessor.__init__(self, host)
        self.request = request
        self.base_url = base_url
        self.mblog_data = mblog_data

    def render(self):
        for entry, comments_data in self.mblog_data:
            comments, comments_rsm = comments_data
            comments = sorted(comments, key=lambda entry: (float(entry.get('published', 0))))
            self.render_html(entry, comments)

    def getText(self, entry, key):
        if ('%s_xhtml' % key) in entry:
            return entry['%s_xhtml' % key].encode('utf-8')
        elif key in entry:
            processor = addURLToText if key.startswith('content') else sanitizeHtml
            return convertNewLinesToXHTML(processor(entry[key])).encode('utf-8')
        return None

    def render_html(self, entry, comments=None):
        """Render one microblog entry.
        @param entry: the microblog entry
        @param base_url: the base url of the blog
        @param request: the HTTP request
        """
        timestamp = float(entry.get('published', 0))
        is_comment = entry['type'] == 'comment'

        data = {'date': datetime.fromtimestamp(timestamp),
                'comments_link': '',
                'previous_comments': '',
                }

        if is_comment:
            author = (_("from %s") % entry['author']).encode('utf-8')
        else:
            author = '&nbsp;'
            message_link = ("%s/%s" % (self.base_url, entry['id'])).encode('utf-8')

            count_text = lambda count: D_('comments') if count > 1 else D_('comment')

            comments_count = int(entry['comments_count'])
            delta = comments_count - len(comments)
            if len(self.mblog_data) == 1 and delta > 0:
                data['comments_link'] = ("%s?max=%s" % (message_link, entry['comments_count']))
                data['previous_comments'] = D_("Show %(count)d previous %(comments)s") % \
                    {'count': delta, 'comments': count_text(delta)}

            data.update({'comments_count': comments_count,
                         'comments_text': count_text(comments_count),
                         'message_link': message_link,
                         'message_title': self.getText(entry, 'title'),
                         })

        data.update({'author': author,
                     'extra_style': 'mblog_comment' if entry['type'] == 'comment' else '',
                     'content': self.getText(entry, 'content'),
                     })

        tpl = "%s%s" % ("" if data.get('message_title', None) else "micro_", "comment" if is_comment else "message")
        self.request.write(self.useTemplate(self.request, tpl, data))

        if comments:
            for comment in comments:
                self.render_html(comment)