1 files changed, 251 insertions, 0 deletions

diff --git a/nautilus/mat2.py b/nautilus/mat2.py
new file mode 100644
index 0000000..133c56d
--- /dev/null
+++ b/nautilus/mat2.py
@@ -0,0 +1,251 @@
+#!/usr/bin/env python3
+
+"""
+Because writing GUI is non-trivial (cf. https://0xacab.org/jvoisin/mat2/issues/3),
+we decided to write a Nautilus extensions instead
+(cf. https://0xacab.org/jvoisin/mat2/issues/2).
+
+The code is a little bit convoluted because Gtk isn't thread-safe,
+so we're not allowed to call anything Gtk-related outside of the main
+thread, so we'll have to resort to using a `queue` to pass "messages" around.
+"""
+
+# pylint: disable=no-name-in-module,unused-argument,no-self-use,import-error
+
+import queue
+import threading
+from typing import Tuple
+from urllib.parse import unquote
+
+import gi
+gi.require_version('Nautilus', '3.0')
+gi.require_version('Gtk', '3.0')
+gi.require_version('GdkPixbuf', '2.0')
+from gi.repository import Nautilus, GObject, Gtk, Gio, GLib, GdkPixbuf
+
+from libmat2 import parser_factory
+
+# make pyflakes happy
+assert Tuple
+
+def _remove_metadata(fpath):
+    """ This is a simple wrapper around libmat2, because it's
+    easier and cleaner this way.
+    """
+    parser, mtype = parser_factory.get_parser(fpath)
+    if parser is None:
+        return False, mtype
+    return parser.remove_all(), mtype
+
+class ColumnExtension(GObject.GObject, Nautilus.MenuProvider, Nautilus.LocationWidgetProvider):
+    """ This class adds an item to the right-clic menu in Nautilus. """
+
+    def __init__(self):
+        super().__init__()
+        self.infobar_hbox = None
+        self.infobar = None
+        self.failed_items = list()
+
+    def __infobar_failure(self):
+        """ Add an hbox to the `infobar` warning about the fact that we didn't
+        manage to remove the metadata from every single file.
+        """
+        self.infobar.set_show_close_button(True)
+        self.infobar_hbox = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL)
+
+        btn = Gtk.Button("Show")
+        btn.connect("clicked", self.__cb_show_failed)
+        self.infobar_hbox.pack_end(btn, False, False, 0)
+
+        infobar_msg = Gtk.Label("Failed to clean some items")
+        self.infobar_hbox.pack_start(infobar_msg, False, False, 0)
+
+        self.infobar.get_content_area().pack_start(self.infobar_hbox, True, True, 0)
+        self.infobar.show_all()
+
+    def get_widget(self, uri, window):
+        """ This is the method that we have to implement (because we're
+        a LocationWidgetProvider) in order to show our infobar.
+        """
+        self.infobar = Gtk.InfoBar()
+        self.infobar.set_message_type(Gtk.MessageType.ERROR)
+        self.infobar.connect("response", self.__cb_infobar_response)
+
+        return self.infobar
+
+    def __cb_infobar_response(self, infobar, response):
+        """ Callback for the infobar close button.
+        """
+        if response == Gtk.ResponseType.CLOSE:
+            self.infobar_hbox.destroy()
+            self.infobar.hide()
+
+    def __cb_show_failed(self, button):
+        """ Callback to show a popup containing a list of files
+        that we didn't manage to clean.
+        """
+
+        # FIXME this should be done only once the window is destroyed
+        self.infobar_hbox.destroy()
+        self.infobar.hide()
+
+        window = Gtk.Window()
+        headerbar = Gtk.HeaderBar()
+        window.set_titlebar(headerbar)
+        headerbar.props.title = "Metadata removal failed"
+
+        close_buton = Gtk.Button("Close")
+        close_buton.connect("clicked", lambda _: window.close())
+        headerbar.pack_end(close_buton)
+
+        box = Gtk.Box(orientation=Gtk.Orientation.VERTICAL)
+        window.add(box)
+
+        box.add(self.__create_treeview())
+        window.show_all()
+
+
+    @staticmethod
+    def __validate(fileinfo) -> Tuple[bool, str]:
+        """ Validate if a given file FileInfo `fileinfo` can be processed.
+        Returns a boolean, and a textreason why"""
+        if fileinfo.get_uri_scheme() != "file" or fileinfo.is_directory():
+            return False, "Not a file"
+        elif not fileinfo.can_write():
+            return False, "Not writeable"
+        return True, ""
+
+
+    def __create_treeview(self) -> Gtk.TreeView:
+        liststore = Gtk.ListStore(GdkPixbuf.Pixbuf, str, str)
+        treeview = Gtk.TreeView(model=liststore)
+
+        renderer_pixbuf = Gtk.CellRendererPixbuf()
+        column_pixbuf = Gtk.TreeViewColumn("Icon", renderer_pixbuf, pixbuf=0)
+        treeview.append_column(column_pixbuf)
+
+        for idx, name in enumerate(['File', 'Reason']):
+            renderer_text = Gtk.CellRendererText()
+            column_text = Gtk.TreeViewColumn(name, renderer_text, text=idx+1)
+            treeview.append_column(column_text)
+
+        for (fname, mtype, reason) in self.failed_items:
+            # This part is all about adding mimetype icons to the liststore
+            icon = Gio.content_type_get_icon('text/plain' if not mtype else mtype)
+            # in case we don't have the corresponding icon,
+            # we're adding `text/plain`, because we have this one for sure™
+            names = icon.get_names() + ['text/plain', ]
+            icon_theme = Gtk.IconTheme.get_default()
+            for name in names:
+                try:
+                    img = icon_theme.load_icon(name, Gtk.IconSize.BUTTON, 0)
+                    break
+                except GLib.GError:
+                    pass
+
+            liststore.append([img, fname, reason])
+
+        treeview.show_all()
+        return treeview
+
+
+    def __create_progressbar(self) -> Gtk.ProgressBar:
+        """ Create the progressbar used to notify that files are currently
+        being processed.
+        """
+        self.infobar.set_show_close_button(False)
+        self.infobar.set_message_type(Gtk.MessageType.INFO)
+        self.infobar_hbox = Gtk.Box(orientation=Gtk.Orientation.HORIZONTAL)
+
+        progressbar = Gtk.ProgressBar()
+        self.infobar_hbox.pack_start(progressbar, True, True, 0)
+        progressbar.set_show_text(True)
+
+        self.infobar.get_content_area().pack_start(self.infobar_hbox, True, True, 0)
+        self.infobar.show_all()
+
+        return progressbar
+
+    def __update_progressbar(self, processing_queue, progressbar) -> bool:
+        """ This method is run via `Glib.add_idle` to update the progressbar."""
+        try:
+            fname = processing_queue.get(block=False)
+        except queue.Empty:
+            return True
+
+        # `None` is the marker put in the queue to signal that every selected
+        # file was processed.
+        if fname is None:
+            self.infobar_hbox.destroy()
+            self.infobar.hide()
+            if len(self.failed_items):
+                self.__infobar_failure()
+            if not processing_queue.empty():
+                print("Something went wrong, the queue isn't empty :/")
+            return False
+
+        progressbar.pulse()
+        progressbar.set_text("Cleaning %s" % fname)
+        progressbar.show_all()
+        self.infobar_hbox.show_all()
+        self.infobar.show_all()
+        return True
+
+    def __clean_files(self, files: list, processing_queue: queue.Queue) -> bool:
+        """ This method is threaded in order to avoid blocking the GUI
+        while cleaning up the files.
+        """
+        for fileinfo in files:
+            fname = fileinfo.get_name()
+            processing_queue.put(fname)
+
+            valid, reason = self.__validate(fileinfo)
+            if not valid:
+                self.failed_items.append((fname, None, reason))
+                continue
+
+            fpath = unquote(fileinfo.get_uri()[7:])  # `len('file://') = 7`
+            success, mtype = _remove_metadata(fpath)
+            if not success:
+                self.failed_items.append((fname, mtype, 'Unsupported/invalid'))
+        processing_queue.put(None)  # signal that we processed all the files
+        return True
+
+
+    def __cb_menu_activate(self, menu, files):
+        """ This method is called when the user clicked the "clean metadata"
+        menu item.
+        """
+        self.failed_items = list()
+        progressbar = self.__create_progressbar()
+        progressbar.set_pulse_step = 1.0 / len(files)
+        self.infobar.show_all()
+
+        processing_queue = queue.Queue()
+        GLib.idle_add(self.__update_progressbar, processing_queue, progressbar)
+
+        thread = threading.Thread(target=self.__clean_files, args=(files, processing_queue))
+        thread.daemon = True
+        thread.start()
+
+
+    def get_background_items(self, window, file):
+        """ https://bugzilla.gnome.org/show_bug.cgi?id=784278 """
+        return None
+
+    def get_file_items(self, window, files):
+        """ This method is the one allowing us to create a menu item.
+        """
+        # Do not show the menu item if not a single file has a chance to be
+        # processed by mat2.
+        if not any([is_valid for (is_valid, _) in map(self.__validate, files)]):
+            return None
+
+        item = Nautilus.MenuItem(
+            name="MAT2::Remove_metadata",
+            label="Remove metadata",
+            tip="Remove metadata"
+        )
+        item.connect('activate', self.__cb_menu_activate, files)
+
+        return [item, ]