Extract XHTML-IM inline imags by default

- Add two new options: tmp_image_dir and extract_inline_images
- tmp_image_dir is $XDG_CACHE_HOME(usually ~/.cache)/poezio/images if unset
- Name the images from a SHA-1 of their data and their mimetype
- Output file:// links inside the message

6 files changed, 104 insertions, 14 deletions

diff --git a/data/default_config.cfg b/data/default_config.cfg
index c1f766b0..35bc498b 100644
--- a/data/default_config.cfg
+++ b/data/default_config.cfg
@@ -379,6 +379,14 @@ ack_message_receipts = true
 # Ask for message delivery receipts (XEP-0184)
 request_message_receipts = true
 
+# Extract base64 images received in XHTML-IM messages
+# if true.
+extract_inline_images = true
+
+# The directory where the images will be saved; if unset,
+# defaults to $XDG_CACHE_HOME/poezio/images.
+tmp_image_dir =
+
 # Receive the tune notifications or not (in order to display informations
 # in the roster).
 # If this is set to false, then the display_tune_notifications
diff --git a/doc/source/configuration.rst b/doc/source/configuration.rst
index 32d82f7a..44fd8e11 100644
--- a/doc/source/configuration.rst
+++ b/doc/source/configuration.rst
@@ -851,6 +851,25 @@ Other
 
         The lang some automated entities will use when replying to you.
 
+    extract_inline_images
+
+        **Default value:** ``true``
+
+        Some clients send inline images in base64 inside some messages, which results in
+        an useless wall of text. If this option is ``true``, then that base64 text will
+        be replaced with a :file:`file://` link to the image file extracted in
+        :term:`tmp_image_dir` or :file:`$XDG_CACHE_HOME/poezio/images` by default, which
+        is usually :file:`~/.cache/poezio/images`
+
+    tmp_image_dir
+
+        **Default value:** ``[empty]``
+
+        The directory where poezio will save the images received, if
+        :term:`extract_inline_images` is set to true. If unset, poezio
+        will default to :file:`$XDG_CACHE_HOME/poezio/images` which is
+        usually :file:`~/.cache/poezio/images`.
+
     muc_history_length
 
         **Default value:** ``50``
diff --git a/src/config.py b/src/config.py
index 354c3447..5bd1ac17 100644
--- a/src/config.py
+++ b/src/config.py
@@ -361,7 +361,6 @@ def file_ok(filepath):
 def check_create_config_dir():
     """
     create the configuration directory if it doesn't exist
-    and copy the default config in it
     """
     CONFIG_HOME = environ.get("XDG_CONFIG_HOME")
     if not CONFIG_HOME:
@@ -374,6 +373,23 @@ def check_create_config_dir():
         pass
     return CONFIG_PATH
 
+def check_create_cache_dir():
+    """
+    create the cache directory if it doesn't exist
+    also create the subdirectories
+    """
+    global CACHE_DIR
+    CACHE_HOME = environ.get("XDG_CACHE_HOME")
+    if not CACHE_HOME:
+        CACHE_HOME = path.join(environ.get('HOME'), '.cache')
+    CACHE_DIR = path.join(CACHE_HOME, 'poezio')
+
+    try:
+        makedirs(CACHE_DIR)
+        makedirs(path.join(CACHE_DIR, 'images'))
+    except OSError:
+        pass
+
 def run_cmdline_args(CONFIG_PATH):
     "Parse the command line arguments"
     global options
@@ -495,3 +511,6 @@ safeJID = None
 
 # the global log dir
 LOG_DIR = ''
+
+# the global cache dir
+CACHE_DIR = ''
diff --git a/src/core/handlers.py b/src/core/handlers.py
index 75c372bb..87aaecd5 100644
--- a/src/core/handlers.py
+++ b/src/core/handlers.py
@@ -10,6 +10,7 @@ import ssl
 import time
 from hashlib import sha1, sha512
 from gettext import gettext as _
+from os import path
 
 from sleekxmpp import InvalidJID
 from sleekxmpp.stanza import Message
@@ -24,7 +25,7 @@ import windows
 import xhtml
 import multiuserchat as muc
 from common import safeJID
-from config import config
+from config import config, CACHE_DIR
 from contact import Resource
 from logger import logger
 from roster import roster
@@ -178,7 +179,11 @@ def on_normal_message(self, message):
         return self.information('%s says: %s' % (message['from'], message['body']), 'Headline')
 
     use_xhtml = config.get('enable_xhtml_im', True)
-    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml)
+    tmp_dir = config.get('tmp_image_dir', '') or path.join(CACHE_DIR, 'images')
+    extract_images = config.get('extract_inline_images', True)
+    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml,
+                                              tmp_dir=tmp_dir,
+                                              extract_images=extract_images)
     if not body:
         return
 
@@ -223,7 +228,9 @@ def on_normal_message(self, message):
     self.events.trigger('conversation_msg', message, conversation)
     if not message['body']:
         return
-    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml)
+    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml,
+                                              tmp_dir=tmp_dir,
+                                              extract_images=extract_images)
     delayed, date = common.find_delayed_tag(message)
 
     def try_modify():
@@ -441,7 +448,11 @@ def on_groupchat_message(self, message):
 
     self.events.trigger('muc_msg', message, tab)
     use_xhtml = config.get('enable_xhtml_im', True)
-    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml)
+    tmp_dir = config.get('tmp_image_dir', '') or path.join(CACHE_DIR, 'images')
+    extract_images = config.get('extract_inline_images', True)
+    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml,
+                                              tmp_dir=tmp_dir,
+                                              extract_images=extract_images)
     if not body:
         return
 
@@ -498,7 +509,11 @@ def on_groupchat_private_message(self, message):
 
     room_from = jid.bare
     use_xhtml = config.get('enable_xhtml_im', True)
-    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml)
+    tmp_dir = config.get('tmp_image_dir', '') or path.join(CACHE_DIR, 'images')
+    extract_images = config.get('extract_inline_images', True)
+    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml,
+                                              tmp_dir=tmp_dir,
+                                              extract_images=extract_images)
     tab = self.get_tab_by_name(jid.full, tabs.PrivateTab) # get the tab with the private conversation
     ignore = config.get_by_tabname('ignore_private', False, room_from)
     if not tab: # It's the first message we receive: create the tab
@@ -511,7 +526,9 @@ def on_groupchat_private_message(self, message):
             self.xmpp.send_message(mto=jid.full, mbody=msg, mtype='chat')
         return
     self.events.trigger('private_msg', message, tab)
-    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml)
+    body = xhtml.get_body_from_message_stanza(message, use_xhtml=use_xhtml,
+                                              tmp_dir=tmp_dir,
+                                              extract_images=extract_images)
     if not body or not tab:
         return
     replaced_id = message['replace']['id']
diff --git a/src/poezio.py b/src/poezio.py
index 1baf10eb..f82f103f 100644
--- a/src/poezio.py
+++ b/src/poezio.py
@@ -30,6 +30,7 @@ def main():
     config.run_cmdline_args(config_path)
     config.create_global_config()
     config.check_create_log_dir()
+    config.check_create_cache_dir()
     config.setup_logging()
     config.post_logging_setup()
 
diff --git a/src/xhtml.py b/src/xhtml.py
index 48664311..69519f8d 100644
--- a/src/xhtml.py
+++ b/src/xhtml.py
@@ -12,9 +12,13 @@ xhtml code to shell colors,
 poezio colors to xhtml code
 """
 
-import re
+import base64
 import curses
+import hashlib
+import re
+from os import path
 from sleekxmpp.xmlstream import ET
+from urllib.parse import unquote
 
 from io import BytesIO
 from xml import sax
@@ -178,10 +182,12 @@ colors = {
 whitespace_re = re.compile(r'\s+')
 
 xhtml_attr_re = re.compile(r'\x19-?\d[^}]*}|\x19[buaio]')
+xhtml_data_re = re.compile(r'data:image/([a-z]+);base64,(.+)')
 
 xhtml_simple_attr_re = re.compile(r'\x19\d')
 
-def get_body_from_message_stanza(message, use_xhtml=False):
+def get_body_from_message_stanza(message, use_xhtml=False,
+                                 tmp_dir=None, extract_images=False):
     """
     Returns a string with xhtml markups converted to
     poezio colors if there's an xhtml_im element, or
@@ -191,7 +197,8 @@ def get_body_from_message_stanza(message, use_xhtml=False):
         xhtml = message['html'].xml
         xhtml_body = xhtml.find('{http://www.w3.org/1999/xhtml}body')
         if xhtml_body:
-            content = xhtml_to_poezio_colors(xhtml_body)
+            content = xhtml_to_poezio_colors(xhtml_body, tmp_dir=tmp_dir,
+                                             extract_images=extract_images)
             content = content if content else message['body']
             return content or " "
     return message['body']
@@ -281,7 +288,7 @@ def trim(string):
     return re.sub(whitespace_re, ' ', string)
 
 class XHTMLHandler(sax.ContentHandler):
-    def __init__(self, force_ns=False):
+    def __init__(self, force_ns=False, tmp_dir=None, extract_images=False):
         self.builder = []
         self.formatting = []
         self.attrs = []
@@ -291,6 +298,9 @@ class XHTMLHandler(sax.ContentHandler):
         # do not care about xhtml-in namespace
         self.force_ns = force_ns
 
+        self.tmp_dir = tmp_dir
+        self.extract_images = extract_images
+
     @property
     def result(self):
         return ''.join(self.builder).strip()
@@ -331,7 +341,22 @@ class XHTMLHandler(sax.ContentHandler):
         elif name == 'em':
             self.append_formatting('\x19i')
         elif name == 'img':
-            builder.append(trim(attrs['src']))
+            if re.match(xhtml_data_re, attrs['src']) and self.extract_images:
+                type_, data = [i for i in re.split(xhtml_data_re, attrs['src']) if i]
+                bin_data = base64.b64decode(unquote(data))
+                filename = hashlib.sha1(bin_data).hexdigest() + '.' + type_
+                filepath = path.join(self.tmp_dir, filename)
+                if not path.exists(filepath):
+                    try:
+                        with open(filepath, 'wb') as fd:
+                            fd.write(bin_data)
+                        builder.append('file://%s' % filepath)
+                    except Exception as e:
+                        builder.append('[Error while saving image: %s]' % e)
+                else:
+                    builder.append('file://%s' % filepath)
+            else:
+                builder.append(trim(attrs['src']))
             if 'alt' in attrs:
                 builder.append(' (%s)' % trim(attrs['alt']))
         elif name == 'ul':
@@ -389,13 +414,14 @@ class XHTMLHandler(sax.ContentHandler):
         if 'title' in attrs:
             builder.append(' [' + attrs['title'] + ']')
 
-def xhtml_to_poezio_colors(xml, force=False):
+def xhtml_to_poezio_colors(xml, force=False, tmp_dir=None, extract_images=None):
     if isinstance(xml, str):
         xml = xml.encode('utf8')
     elif not isinstance(xml, bytes):
         xml = ET.tostring(xml)
 
-    handler = XHTMLHandler(force_ns=force)
+    handler = XHTMLHandler(force_ns=force, tmp_dir=tmp_dir,
+                           extract_images=extract_images)
     parser = sax.make_parser()
     parser.setFeature(sax.handler.feature_namespaces, True)
     parser.setContentHandler(handler)