--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/cagou/core/simple_xhtml.py	Sun Jan 15 21:21:20 2017 +0100
@@ -0,0 +1,498 @@
+#!/usr/bin/python
+# -*- coding: utf-8 -*-
+
+# Cagou: desktop/mobile frontend for Salut à Toi XMPP client
+# Copyright (C) 2016 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 import log as logging
+log = logging.getLogger(__name__)
+from kivy.uix.stacklayout import StackLayout
+from kivy.uix.label import Label
+from kivy.utils import escape_markup
+from kivy import properties
+from xml.etree import ElementTree as ET
+from sat_frontends.tools import css_color, strings as sat_strings
+from cagou.core.image import AsyncImage
+import webbrowser
+
+
+class Escape(unicode):
+    """Class used to mark that a message need to be escaped"""
+
+    def __init__(self, text):
+        super(Escape, self).__init__(text)
+
+
+class SimpleXHTMLWidgetEscapedText(Label):
+
+    def _addUrlMarkup(self, text):
+        text_elts = []
+        idx = 0
+        links = 0
+        while True:
+            m = sat_strings.RE_URL.search(text[idx:])
+            if m is not None:
+                text_elts.append(escape_markup(m.string[0:m.start()]))
+                link_key = u'link_' + unicode(links)
+                url = m.group()
+                text_elts.append(u'[color=5500ff][ref={link}]{url}[/ref][/color]'.format(
+                    link = link_key,
+                    url = url
+                    ))
+                if not links:
+                    self.ref_urls = {link_key: url}
+                else:
+                    self.ref_urls[link_key] = url
+                links += 1
+                idx += m.end()
+            else:
+                if links:
+                    text_elts.append(escape_markup(text[idx:]))
+                    self.markup = True
+                    self.text = u''.join(text_elts)
+                break
+
+    def on_text(self, instance, text):
+        # do NOT call the method if self.markup is set
+        # this would result in infinite loop (because self.text
+        # is changed if an URL is found, and in this case markup too)
+        if text and not self.markup:
+            self._addUrlMarkup(text)
+
+    def on_ref_press(self, ref):
+        url = self.ref_urls[ref]
+        webbrowser.open(url)
+
+
+class SimpleXHTMLWidgetText(Label):
+    pass
+
+
+class SimpleXHTMLWidgetImage(AsyncImage):
+    # following properties are desired height/width
+    # i.e. the ones specified in height/width attributes of <img>
+    # (or wanted for whatever reason)
+    # set to 0 to ignore them
+    target_height = properties.NumericProperty()
+    target_width = properties.NumericProperty()
+
+    def _get_parent_container(self):
+        """get parent SimpleXHTMLWidget instance
+
+        @param warning(bool): if True display a log.error if nothing found
+        @return (SimpleXHTMLWidget, None): found SimpleXHTMLWidget instance
+        """
+        parent = self.parent
+        while parent and not isinstance(parent, SimpleXHTMLWidget):
+            parent = parent.parent
+        if parent is None:
+            log.error(u"no SimpleXHTMLWidget parent found")
+        return parent
+
+    def _on_source_load(self, value):
+        # this method is called when image is loaded
+        super(SimpleXHTMLWidgetImage, self)._on_source_load(value)
+        if self.parent is not None:
+            container = self._get_parent_container()
+            # image is loaded, we need to recalculate size
+            self.on_container_width(container, container.width)
+
+    def on_container_width(self, container, container_width):
+        """adapt size according to container width
+
+        called when parent container (SimpleXHTMLWidget) width change
+        """
+        target_size = (self.target_width or self.texture.width, self.target_height or self.texture.height)
+        padding = container.padding
+        padding_h = (padding[0] + padding[2]) if len(padding) == 4 else padding[0]
+        width = container_width - padding_h
+        if target_size[0] < width:
+            self.size = target_size
+        else:
+            height = width / self.image_ratio
+            self.size = (width, height)
+
+    def on_parent(self, instance, parent):
+        if parent is not None:
+            container = self._get_parent_container()
+            container.bind(width=self.on_container_width)
+
+
+class SimpleXHTMLWidget(StackLayout):
+    """widget handling simple XHTML parsing"""
+    xhtml = properties.StringProperty()
+    color = properties.ListProperty([1, 1, 1, 1])
+    # XXX: bold is only used for escaped text
+    bold = properties.BooleanProperty(False)
+    content_width = properties.NumericProperty(0)
+
+    # text/XHTML input
+
+    def on_xhtml(self, instance, xhtml):
+        """parse xhtml and set content accordingly
+
+        if xhtml is an instance of Escape, a Label with not markup
+        will be used
+        """
+        self.clear_widgets()
+        if isinstance(xhtml, Escape):
+            label = SimpleXHTMLWidgetEscapedText(text=xhtml, color=self.color)
+            self.bind(color=label.setter('color'))
+            self.bind(bold=label.setter('bold'))
+            self.add_widget(label)
+        else:
+            xhtml = ET.fromstring(xhtml.encode('utf-8'))
+            self.current_wid = None
+            self.styles = []
+            self._callParseMethod(xhtml)
+
+    def escape(self, text):
+        """mark that a text need to be escaped (i.e. no markup)"""
+        return Escape(text)
+
+    # sizing
+
+    def on_width(self, instance, width):
+        if len(self.children) == 1:
+            wid = self.children[0]
+            if isinstance(wid, Label):
+                # we have simple text
+                try:
+                    full_width = wid._full_width
+                except AttributeError:
+                    # on first time, we need the required size
+                    # for the full text, without width limit
+                    wid.size_hint = (None, None)
+                    wid.texture_update()
+                    full_width = wid._full_width = wid.texture_size[0]
+
+                if full_width > width:
+                    wid.text_size = width, None
+                    wid.width = width
+                else:
+                    wid.text_size = None, None
+                    wid.texture_update()
+                    wid.width = wid.texture_size[0]
+                self.content_width = wid.width + self.padding[0] + self.padding[2]
+            else:
+                wid.size_hint = (1, None)
+                wid.height = 100
+                self.content_width = self.width
+        else:
+            self._do_complexe_sizing(width)
+
+    def _do_complexe_sizing(self, width):
+        try:
+            self.splitted
+        except AttributeError:
+            # XXX: to make things easier, we split labels in words
+            log.debug(u"split start")
+            children = self.children[::-1]
+            self.clear_widgets()
+            for child in children:
+                if isinstance(child, Label):
+                    log.debug(u"label before split: {}".format(child.text))
+                    styles = []
+                    tag = False
+                    new_text = []
+                    current_tag = []
+                    current_value = []
+                    current_wid = self._createText()
+                    value = False
+                    close = False
+                    # we will parse the text and create a new widget
+                    # on each new word (actually each space)
+                    # FIXME: handle '\n' and other white chars
+                    for c in child.text:
+                        if tag:
+                            # we are parsing a markup tag
+                            if c == u']':
+                                current_tag_s = u''.join(current_tag)
+                                current_style = (current_tag_s, u''.join(current_value))
+                                if close:
+                                    for idx, s in enumerate(reversed(styles)):
+                                        if s[0] == current_tag_s:
+                                            del styles[len(styles) - idx - 1]
+                                            break
+                                else:
+                                    styles.append(current_style)
+                                current_tag = []
+                                current_value = []
+                                tag = False
+                                value = False
+                                close = False
+                            elif c == u'/':
+                                close = True
+                            elif c == u'=':
+                                value = True
+                            elif value:
+                                current_value.append(c)
+                            else:
+                                current_tag.append(c)
+                            new_text.append(c)
+                        else:
+                            # we are parsing regular text
+                            if c == u'[':
+                                new_text.append(c)
+                                tag = True
+                            elif c == u' ':
+                                # new word, we do a new widget
+                                new_text.append(u' ')
+                                for t, v in reversed(styles):
+                                    new_text.append(u'[/{}]'.format(t))
+                                current_wid.text = u''.join(new_text)
+                                new_text = []
+                                self.add_widget(current_wid)
+                                log.debug(u"new widget: {}".format(current_wid.text))
+                                current_wid = self._createText()
+                                for t, v in styles:
+                                    new_text.append(u'[{tag}{value}]'.format(
+                                        tag = t,
+                                        value = u'={}'.format(v) if v else u''))
+                            else:
+                                new_text.append(c)
+                    if current_wid.text:
+                        # we may have a remaining widget after the parsing
+                        close_styles = []
+                        for t, v in reversed(styles):
+                            close_styles.append(u'[/{}]'.format(t))
+                        current_wid.text = u''.join(close_styles)
+                        self.add_widget(current_wid)
+                        log.debug(u"new widget: {}".format(current_wid.text))
+                else:
+                    # non Label widgets, we just add them
+                    self.add_widget(child)
+            self.splitted = True
+            log.debug(u"split OK")
+
+        # we now set the content width
+        # FIXME: for now we just use the full width
+        self.content_width = width
+
+    # XHTML parsing methods
+
+    def _callParseMethod(self, e):
+        """call the suitable method to parse the element
+
+        self.xhtml_[tag] will be called if it exists, else
+        self.xhtml_generic will be used
+        @param e(ET.Element): element to parse
+        """
+        try:
+            method = getattr(self, "xhtml_{}".format(e.tag))
+        except AttributeError:
+            log.warning(u"Unhandled XHTML tag: {}".format(e.tag))
+            method = self.xhtml_generic
+        method(e)
+
+    def _addStyle(self, tag, value=None, append_to_list=True):
+        """add a markup style to label
+
+        @param tag(unicode): markup tag
+        @param value(unicode): markup value if suitable
+        @param append_to_list(bool): if True style we be added to self.styles
+            self.styles is needed to keep track of styles to remove
+            should most probably be set to True
+        """
+        label = self._getLabel()
+        label.text += u'[{tag}{value}]'.format(
+            tag = tag,
+            value = u'={}'.format(value) if value else ''
+            )
+        if append_to_list:
+            self.styles.append((tag, value))
+
+    def _removeStyle(self, tag, remove_from_list=True):
+        """remove a markup style from the label
+
+        @param tag(unicode): markup tag to remove
+        @param remove_from_list(bool): if True, remove from self.styles too
+            should most probably be set to True
+        """
+        label = self._getLabel()
+        label.text += u'[/{tag}]'.format(
+            tag = tag
+            )
+        if remove_from_list:
+            for rev_idx, style in enumerate(reversed(self.styles)):
+                if style[0] == tag:
+                    tag_idx = len(self.styles) - 1 - rev_idx
+                    del self.styles[tag_idx]
+                    break
+
+    def _getLabel(self):
+        """get current Label if it exists, or create a new one"""
+        if not isinstance(self.current_wid, Label):
+            self._addLabel()
+        return self.current_wid
+
+    def _addLabel(self):
+        """add a new Label
+
+        current styles will be closed and reopened if needed
+        """
+        self._closeLabel()
+        self.current_wid = self._createText()
+        for tag, value in self.styles:
+            self._addStyle(tag, value, append_to_list=False)
+        self.add_widget(self.current_wid)
+
+    def _createText(self):
+        label = SimpleXHTMLWidgetText(color=self.color, markup=True)
+        self.bind(color=label.setter('color'))
+        label.bind(texture_size=label.setter('size'))
+        return label
+
+    def _closeLabel(self):
+        """close current style tags in current label
+
+        needed when you change label to keep style between
+        different widgets
+        """
+        if isinstance(self.current_wid, Label):
+            for tag, value in reversed(self.styles):
+                self._removeStyle(tag, remove_from_list=False)
+
+    def _parseCSS(self, e):
+        """parse CSS found in "style" attribute of element
+
+        self._css_styles will be created and contained markup styles added by this method
+        @param e(ET.Element): element which may have a "style" attribute
+        """
+        styles_limit = len(self.styles)
+        styles = e.attrib['style'].split(u';')
+        for style in styles:
+            try:
+                prop, value = style.split(u':')
+            except ValueError:
+                log.warning(u"can't parse style: {}".format(style))
+                continue
+            prop = prop.strip().replace(u'-', '_')
+            value = value.strip()
+            try:
+                method = getattr(self, "css_{}".format(prop))
+            except AttributeError:
+                log.warning(u"Unhandled CSS: {}".format(prop))
+            else:
+                method(e, value)
+        self._css_styles = self.styles[styles_limit:]
+
+    def _closeCSS(self):
+        """removed CSS styles
+
+        styles in self._css_styles will be removed
+        and the attribute will be deleted
+        """
+        for tag, dummy in reversed(self._css_styles):
+            self._removeStyle(tag)
+        del self._css_styles
+
+    def xhtml_generic(self, elem, style=True, markup=None):
+        """generic method for adding HTML elements
+
+        this method handle content, style and children parsing
+        @param elem(ET.Element): element to add
+        @param style(bool): if True handle style attribute (CSS)
+        @param markup(tuple[unicode, (unicode, None)], None): kivy markup to use
+        """
+        # we first add markup and CSS style
+        if markup is not None:
+            if isinstance(markup, basestring):
+                tag, value = markup, None
+            else:
+                tag, value = markup
+            self._addStyle(tag, value)
+        style_ = 'style' in elem.attrib and style
+        if style_:
+            self._parseCSS(elem)
+
+        # then content
+        if elem.text:
+            self._getLabel().text += escape_markup(elem.text)
+
+        # we parse the children
+        for child in elem:
+            self._callParseMethod(child)
+
+        # closing CSS style and markup
+        if style_:
+            self._closeCSS()
+        if markup is not None:
+            self._removeStyle(tag)
+
+        # and the tail, which is regular text
+        if elem.tail:
+            self._getLabel().text += escape_markup(elem.tail)
+
+    # method handling XHTML elements
+
+    def xhtml_br(self, elem):
+        label = self._getLabel()
+        label.text+='\n'
+        self.xhtml_generic(style=False)
+
+    def xhtml_em(self, elem):
+        self.xhtml_generic(elem, markup='i')
+
+    def xhtml_img(self, elem):
+        try:
+            src = elem.attrib['src']
+        except KeyError:
+            log.warning(u"<img> element without src: {}".format(ET.tostring(elem)))
+            return
+        try:
+            target_height = int(elem.get(u'height', 0))
+        except ValueError:
+            log.warning(u"Can't parse image height: {}".format(elem.get(u'height')))
+            target_height = 0
+        try:
+            target_width = int(elem.get(u'width', 0))
+        except ValueError:
+            log.warning(u"Can't parse image width: {}".format(elem.get(u'width')))
+            target_width = 0
+
+        img = SimpleXHTMLWidgetImage(source=src, target_height=target_height, target_width=target_width)
+        self.current_wid = img
+        self.add_widget(img)
+
+    def xhtml_p(self, elem):
+        if isinstance(self.current_wid, Label):
+            self.current_wid.text+="\n\n"
+        self.xhtml_generic(elem)
+
+    def xhtml_span(self, elem):
+        self.xhtml_generic(elem)
+
+    def xhtml_strong(self, elem):
+        self.xhtml_generic(elem, markup='b')
+
+    # methods handling CSS properties
+
+    def css_color(self, elem, value):
+        self._addStyle(u"color", css_color.parse(value))
+
+    def css_text_decoration(self, elem, value):
+        if value == u'underline':
+            log.warning(u"{} not handled yet, it needs Kivy 1.9.2 to be released".format(value))
+            # FIXME: activate when 1.9.2 is out
+            # self._addStyle('u')
+        elif value == u'line-through':
+            log.warning(u"{} not handled yet, it needs Kivy 1.9.2 to be released".format(value))
+            # FIXME: activate when 1.9.2 is out
+            # self._addStyle('s')
+        else:
+            log.warning(u"unhandled text decoration: {}".format(value))