# Copyright (C) 2006, Red Hat, Inc.
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2 of the License, or (at your option) any later version.
#
# This library 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
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public
# License along with this library; if not, write to the
# Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.

#!/usr/bin/env python

import sha

import dbus
import dbus.service
import dbus.glib

import gtk
import gobject
import pango
import logging

from sugar.chat.Emoticons import Emoticons
from sugar.chat.ChatToolbar import ChatToolbar
from sugar.chat.ChatEditor import ChatEditor
from sugar.presence import PresenceService
import richtext

PANGO_SCALE = 1024 # Where is this defined?

class Chat(gtk.VBox):
    SERVICE_TYPE = "_olpc_chat._tcp"
    SERVICE_PORT = 6100

    TEXT_MODE = 0
    SKETCH_MODE = 1

    def __init__(self):
        gtk.VBox.__init__(self, False, 6)

        self._pservice = PresenceService.get_instance()

        self._stream_writer = None
        self.set_border_width(12)

        chat_vbox = gtk.VBox()
        chat_vbox.set_spacing(6)

        self._chat_sw = gtk.ScrolledWindow()
        self._chat_sw.set_shadow_type(gtk.SHADOW_IN)
        self._chat_sw.set_policy(gtk.POLICY_NEVER, gtk.POLICY_ALWAYS)
        self._chat_view = richtext.RichTextView()
        self._chat_view.connect("link-clicked", self.__link_clicked_cb)
        self._chat_view.set_editable(False)
        self._chat_view.set_cursor_visible(False)
        self._chat_view.set_pixels_above_lines(7)
        self._chat_view.set_left_margin(5)
        self._chat_sw.add(self._chat_view)
        self._chat_view.show()
        chat_vbox.pack_start(self._chat_sw)
        self._chat_sw.show()
        
        self.pack_start(chat_vbox)
        chat_vbox.show()

        self._mode = Chat.TEXT_MODE
        self._editor = ChatEditor(self, ChatEditor.TEXT_MODE)

        toolbar = ChatToolbar(self._editor)
        self.pack_start(toolbar, False)
        toolbar.show()

        self.pack_start(self._editor, False)
        self._editor.show()

        self.connect("key-press-event", self.__key_press_event_cb)

    def __key_press_event_cb(self, window, event):
        if event.keyval == gtk.keysyms.s and \
           event.state & gtk.gdk.CONTROL_MASK:
            if self.get_mode() == Chat.SKETCH_MODE:
                self.set_mode(Chat.TEXT_MODE)
            elif self.get_mode() == Chat.TEXT_MODE:
                self.set_mode(Chat.SKETCH_MODE)

    def get_mode(self):
        return self._mode

    def set_mode(self, mode):
        self._mode = mode
        if self._mode == Chat.TEXT_MODE:
            self._editor.set_mode(ChatEditor.TEXT_MODE)
        elif self._mode == Chat.SKETCH_MODE:
            self._editor.set_mode(ChatEditor.SKETCH_MODE)

    def __get_browser_shell(self):
        bus = dbus.SessionBus()
        proxy_obj = bus.get_object('com.redhat.Sugar.Browser', '/com/redhat/Sugar/Browser')
        self._browser_shell = dbus.Interface(proxy_obj, 'com.redhat.Sugar.BrowserShell')

    def __link_clicked_cb(self, view, address):
        self.__get_browser_shell().open_browser(address)

    def _scroll_chat_view_to_bottom(self):
        # Only scroll to bottom if the view is already close to the bottom
        vadj = self._chat_sw.get_vadjustment()
        if vadj.value + vadj.page_size > vadj.upper * 0.8:
            vadj.value = vadj.upper - vadj.page_size
            self._chat_sw.set_vadjustment(vadj)

    def _message_inserted(self):
        gobject.idle_add(self._scroll_chat_view_to_bottom)

    def _insert_buddy(self, buf, buddy):
        # Stuff in the buddy icon, if we have one for this buddy
        icon = buddy.get_icon_pixbuf()
        if icon:
            rise = int(icon.get_height() / 4) * -1

            hash_string = "%s-%s" % (buddy.get_name(), buddy.get_ip4_address())
            sha_hash = sha.new()
            sha_hash.update(hash_string)
            tagname = "buddyicon-%s" % sha_hash.hexdigest()

            if not buf.get_tag_table().lookup(tagname):
                buf.create_tag(tagname, rise=(rise * PANGO_SCALE))

            aniter = buf.get_end_iter()
            buf.insert_pixbuf(aniter, icon)
            aniter.backward_char()
            enditer = buf.get_end_iter()
            buf.apply_tag_by_name(tagname, aniter, enditer)

        # Stick in the buddy's nickname
        if not buf.get_tag_table().lookup("nickname"):
            buf.create_tag("nickname", weight=pango.WEIGHT_BOLD)
        aniter = buf.get_end_iter()
        offset = aniter.get_offset()
        buf.insert(aniter, " " + buddy.get_name() + ": ")
        enditer = buf.get_iter_at_offset(offset)
        buf.apply_tag_by_name("nickname", aniter, enditer)
        
    def _insert_rich_message(self, buddy, msg):
        msg = Emoticons.get_instance().replace(msg)

        buf = self._chat_view.get_buffer()
        self._insert_buddy(buf, buddy)
        
        serializer = richtext.RichTextSerializer()
        serializer.deserialize(msg, buf)
        aniter = buf.get_end_iter()
        buf.insert(aniter, "\n")
        
        self._message_inserted()

    def _insert_sketch(self, buddy, svgdata):
        """Insert a sketch object into the chat buffer."""
        pbl = gtk.gdk.PixbufLoader("svg")
        pbl.write(svgdata)
        pbl.close()
        pbuf = pbl.get_pixbuf()
        
        buf = self._chat_view.get_buffer()

        self._insert_buddy(buf, buddy)
        
        rise = int(pbuf.get_height() / 3) * -1
        sha_hash = sha.new()
        sha_hash.update(svgdata)
        tagname = "sketch-%s" % sha_hash.hexdigest()
        if not buf.get_tag_table().lookup(tagname):
            buf.create_tag(tagname, rise=(rise * PANGO_SCALE))

        aniter = buf.get_end_iter()
        buf.insert_pixbuf(aniter, pbuf)
        aniter.backward_char()
        enditer = buf.get_end_iter()
        buf.apply_tag_by_name(tagname, aniter, enditer)
        aniter = buf.get_end_iter()
        buf.insert(aniter, "\n")

        self._message_inserted()

    def _get_first_richtext_chunk(self, msg):
        """Scan the message for the first richtext-tagged chunk and return it."""
        rt_last = -1
        tag_rt_start = "<richtext>"
        tag_rt_end = "</richtext>"
        rt_first = msg.find(tag_rt_start)
        length = -1
        if rt_first >= 0:
            length = len(msg)
            rt_last = msg.find(tag_rt_end, rt_first)
        if rt_first >= 0 and rt_last >= (rt_first + len(tag_rt_start)) and length > 0:
            return msg[rt_first:rt_last + len(tag_rt_end)]
        return None

    def _get_first_sketch_chunk(self, msg):
        """Scan the message for the first SVG-tagged chunk and return it."""
        svg_last = -1
        tag_svg_start = "<svg"
        tag_svg_end = "</svg>"
        desc_start = msg.find("<?xml version='1.0' encoding='UTF-8'?>")
        if desc_start < 0:
            return None
        ignore = msg.find("<!DOCTYPE svg")
        if ignore < 0:
            return None
        svg_first = msg.find(tag_svg_start)
        length = -1
        if svg_first >= 0:
            length = len(msg)
            svg_last = msg.find(tag_svg_end, svg_first)
        if svg_first >= 0 and svg_last >= (svg_first + len(tag_svg_start)) and length > 0:
            return msg[desc_start:svg_last + len(tag_svg_end)]
        return None

    def recv_message(self, message):
        """Insert a remote chat message into the chat buffer."""
        [nick, msg] = Chat.deserialize_message(message)
        buddy = self._pservice.get_buddy_by_name(nick)
        if not buddy:
            logging.error('The buddy %s is not present.' % (nick))
            return

        # FIXME a better way to compare buddies?            
        owner = self._pservice.get_owner()
        if buddy.get_name() == owner.get_name():
            return

        chunk = self._get_first_richtext_chunk(msg)
        if chunk:
            self._insert_rich_message(buddy, chunk)
            return

        chunk = self._get_first_sketch_chunk(msg)
        if chunk:
            self._insert_sketch(buddy, chunk)
            return

    def set_stream_writer(self, stream_writer):
        self._stream_writer = stream_writer

    def send_sketch(self, svgdata):
        if not svgdata or not len(svgdata):
            return
        if self._stream_writer:
            self._stream_writer.write(self.serialize_message(svgdata))
        owner = self._pservice.get_owner()
        if owner:
            self._insert_sketch(owner, svgdata)

    def send_text_message(self, text):
        """Send a chat message and insert it into the local buffer."""
        if len(text) <= 0:
            return
        if self._stream_writer:
            self._stream_writer.write(self.serialize_message(text))
        else:
            logging.warning("Cannot send message, there is no stream writer")
        owner = self._pservice.get_owner()
        if owner:
            self._insert_rich_message(owner, text)

    def serialize_message(self, message):
        owner = self._pservice.get_owner()
        return owner.get_name() + '||' + message
        
    def deserialize_message(message):
        return message.split('||', 1)

    deserialize_message = staticmethod(deserialize_message)