--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/libervia/backend/plugins/plugin_xep_0446.py	Fri Jun 02 11:49:51 2023 +0200
@@ -0,0 +1,165 @@
+#!/usr/bin/env python3
+
+# Copyright (C) 2009-2022 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 logging import exception
+from typing import Optional, Union, Tuple, Dict, Any
+from pathlib import Path
+
+from twisted.words.xish import domish
+
+from libervia.backend.core.constants import Const as C
+from libervia.backend.core.i18n import _
+from libervia.backend.core.log import getLogger
+from libervia.backend.core import exceptions
+from libervia.backend.tools import utils
+
+log = getLogger(__name__)
+
+
+PLUGIN_INFO = {
+    C.PI_NAME: "File Metadata Element",
+    C.PI_IMPORT_NAME: "XEP-0446",
+    C.PI_TYPE: "XEP",
+    C.PI_MODES: C.PLUG_MODE_BOTH,
+    C.PI_PROTOCOLS: ["XEP-0446"],
+    C.PI_DEPENDENCIES: ["XEP-0300"],
+    C.PI_MAIN: "XEP_0446",
+    C.PI_HANDLER: "no",
+    C.PI_DESCRIPTION: _("""Implementation of XEP-0446 (File Metadata Element)"""),
+}
+
+NS_FILE_METADATA = "urn:xmpp:file:metadata:0"
+
+
+class XEP_0446:
+
+    def __init__(self, host):
+        log.info(_("XEP-0446 (File Metadata Element) plugin initialization"))
+        host.register_namespace("file-metadata", NS_FILE_METADATA)
+        self._hash = host.plugins["XEP-0300"]
+
+    def get_file_metadata_elt(
+        self,
+        name: Optional[str] = None,
+        media_type: Optional[str] = None,
+        desc: Optional[str] = None,
+        size: Optional[int] = None,
+        file_hash: Optional[Tuple[str, str]] = None,
+        date: Optional[Union[float, int]] = None,
+        width: Optional[int] = None,
+        height: Optional[int] = None,
+        length: Optional[int] = None,
+        thumbnail: Optional[str] = None,
+    ) -> domish.Element:
+        """Generate the element describing a file
+
+        @param name: name of the file
+        @param media_type: media-type
+        @param desc: description
+        @param size: size in bytes
+        @param file_hash: (algo, hash)
+        @param date: timestamp of the last modification datetime
+        @param width: image width in pixels
+        @param height: image height in pixels
+        @param length: video length in seconds
+        @param thumbnail: URL to a thumbnail
+        @return: ``<file/>`` element
+        """
+        if name:
+            name = Path(name).name
+        file_elt = domish.Element((NS_FILE_METADATA, "file"))
+        for name, value in (
+            ("name", name),
+            ("media-type", media_type),
+            ("desc", desc),
+            ("size", size),
+            ("width", width),
+            ("height", height),
+            ("length", length),
+        ):
+            if value is not None:
+                file_elt.addElement(name, content=str(value))
+        if file_hash is not None:
+            hash_algo, hash_ = file_hash
+            file_elt.addChild(self._hash.build_hash_elt(hash_, hash_algo))
+        if date is not None:
+            file_elt.addElement("date", utils.xmpp_date(date))
+        if thumbnail is not None:
+            # TODO: implement thumbnails
+            log.warning("thumbnail is not implemented yet")
+        return file_elt
+
+    def parse_file_metadata_elt(
+        self,
+        file_metadata_elt: domish.Element
+    ) -> Dict[str, Any]:
+        """Parse <file/> element
+
+        @param file_metadata_elt: <file/> element
+            a parent element can also be used
+        @return: file metadata. It's a dict whose keys correspond to
+            [get_file_metadata_elt] parameters
+        @raise exceptions.NotFound: no <file/> element has been found
+        """
+
+        if file_metadata_elt.name != "file":
+            try:
+                file_metadata_elt = next(
+                    file_metadata_elt.elements(NS_FILE_METADATA, "file")
+                )
+            except StopIteration:
+                raise exceptions.NotFound
+        data: Dict[str, Any] = {}
+
+        for key, type_ in (
+            ("name", str),
+            ("media-type", str),
+            ("desc", str),
+            ("size", int),
+            ("date", "timestamp"),
+            ("width", int),
+            ("height", int),
+            ("length", int),
+        ):
+            elt = next(file_metadata_elt.elements(NS_FILE_METADATA, key), None)
+            if elt is not None:
+                if type_ in (str, int):
+                    content = str(elt)
+                    if key == "name":
+                        # we avoid malformed names or names containing path elements
+                        content = Path(content).name
+                    elif key == "media-type":
+                        key = "media_type"
+                    data[key] = type_(content)
+                elif type == "timestamp":
+                    data[key] = utils.parse_xmpp_date(str(elt))
+                else:
+                    raise exceptions.InternalError
+
+        try:
+            algo, hash_ = self._hash.parse_hash_elt(file_metadata_elt)
+        except exceptions.NotFound:
+            pass
+        except exceptions.DataError:
+            from libervia.backend.tools.xml_tools import p_fmt_elt
+            log.warning("invalid <hash/> element:\n{p_fmt_elt(file_metadata_elt)}")
+        else:
+            data["file_hash"] = (algo, hash_)
+
+        # TODO: thumbnails
+
+        return data