[Dextrose] [PATCH] Journal space messages alert and improved modal alert

[Martin Abente]

Based on the comments from #630

When available space reaches the _PREEMPTIVE_SPACE_TRESHOLD
(75MB) a message notification will be displayed on every startup.

When available space reaches the _SPACE_TRESHOLD (50MB) the
ModalaAlert will be displayed.

Changes on the ModaAlert:

* It will remain active until there is enough available space again.
* It will be deactivated when the journal is on the foreground
  and it will be activated again otherwise.
* It contains a new progressbar to determine intuitively how much
  deletion is required to reach the safe state again.
---
 src/jarabe/journal/journalactivity.py |   47 +++++++++++++++++++++++++-------
 src/jarabe/journal/modalalert.py      |   28 +++++++++++++++++--
 2 files changed, 61 insertions(+), 14 deletions(-)

diff --git a/src/jarabe/journal/journalactivity.py b/src/jarabe/journal/journalactivity.py
index eab292b..66299c9 100644
--- a/src/jarabe/journal/journalactivity.py
+++ b/src/jarabe/journal/journalactivity.py
@@ -45,13 +45,16 @@ from jarabe.journal.journalentrybundle import JournalEntryBundle
 from jarabe.journal.objectchooser import ObjectChooser
 from jarabe.journal.modalalert import ModalAlert
 from jarabe.journal import model
+from jarabe.frame import get_view
 
 J_DBUS_SERVICE = 'org.laptop.Journal'
 J_DBUS_INTERFACE = 'org.laptop.Journal'
 J_DBUS_PATH = '/org/laptop/Journal'
 
 _SPACE_TRESHOLD = 52428800
+_PREEMPTIVE_SPACE_TRESHOLD = _SPACE_TRESHOLD * 1.5
 _BUNDLE_ID = 'org.laptop.JournalActivity'
+_JOURNAL_ICON = 'activity-journal'
 
 class JournalActivityDBusService(dbus.service.Object):
     def __init__(self, parent):
@@ -139,7 +142,7 @@ class JournalActivity(Window):
         self.iconify()
 
         self._critical_space_alert = None
-        self._check_available_space()
+        self._check_available_space(startup=True)
 
     def _alert_notify_cb(self, gobject, strerror, severity):
         alert = ErrorAlert()
@@ -273,6 +276,9 @@ class JournalActivity(Window):
                 kwargs['object_id'] == self._detail_view.props.metadata['uid']:
             self.show_main_view()
 
+        if self._critical_space_alert:
+           self._check_available_space(display=False)
+
     def _focus_in_event_cb(self, window, event):
         self.search_grab_focus()
         self._list_view.update_dates()
@@ -324,32 +330,51 @@ class JournalActivity(Window):
             visible = not state & gtk.gdk.WINDOW_STATE_ICONIFIED
             self._list_view.set_is_visible(visible)
 
+            if self._critical_space_alert and not visible:
+                self._check_available_space()
+
     def __visibility_notify_event_cb(self, window, event):
         logging.debug('visibility_notify_event_cb %r', self)
         visible = event.state != gtk.gdk.VISIBILITY_FULLY_OBSCURED
         self._list_view.set_is_visible(visible)
 
-    def _check_available_space(self):
+    def _check_available_space(self, startup=False, display=True):
         ''' Check available space on device
 
             If the available space is below 50MB an alert will be
             shown which encourages to delete old journal entries.
         '''
-
-        if self._critical_space_alert:
-            return
         stat = os.statvfs(env.get_profile_path())
         free_space = stat[statvfs.F_BSIZE] * stat[statvfs.F_BAVAIL]
-        if free_space < _SPACE_TRESHOLD:
+
+        if self._critical_space_alert and free_space >= _SPACE_TRESHOLD:
+            self._critical_space_alert.destroy()
+            self._critical_space_alert = None
+
+        elif free_space < _SPACE_TRESHOLD:
+            space_fraction = 1.0 - (float(free_space) / float(_SPACE_TRESHOLD))
+            self._setup_space_alert(space_fraction, display)
+
+        elif startup and free_space < _PREEMPTIVE_SPACE_TRESHOLD:
+            body = _('Your Journal currently contains too much entries' 
+                    ' please consider removing unnecessary ones')
+
+            frame = get_view()
+            frame.add_message(body, icon_name=_JOURNAL_ICON)
+
+    def _setup_space_alert(self, space_fraction, display):
+        if self._critical_space_alert is None:
             self._critical_space_alert = ModalAlert()
-            self._critical_space_alert.connect('destroy',
-                                               self.__alert_closed_cb)
-            self._critical_space_alert.show()
+            self._critical_space_alert.connect('show-journal',
+                                               self.__show_journal_cb)
+        self._critical_space_alert.update_space_fraction(space_fraction)
+        if display:
+            self._critical_space_alert.present()
 
-    def __alert_closed_cb(self, data):
+    def __show_journal_cb(self, data):
         self.show_main_view()
         self.reveal()
-        self._critical_space_alert = None
+        self._critical_space_alert.hide()
 
     def set_active_volume(self, mount):
         self._volumes_toolbar.set_active_volume(mount)
diff --git a/src/jarabe/journal/modalalert.py b/src/jarabe/journal/modalalert.py
index c7c6a0a..0c774e7 100644
--- a/src/jarabe/journal/modalalert.py
+++ b/src/jarabe/journal/modalalert.py
@@ -17,6 +17,7 @@
 import gtk
 from gettext import gettext as _
 import gconf
+import gobject
 
 from sugar.graphics.icon import Icon
 from sugar.graphics import style
@@ -26,6 +27,10 @@ class ModalAlert(gtk.Window):
 
     __gtype_name__ = 'SugarModalAlert'
 
+    __gsignals__ = {
+        'show-journal': (gobject.SIGNAL_RUN_FIRST, gobject.TYPE_NONE, ([]))
+    }
+
     def __init__(self):
         gtk.Window.__init__(self)
 
@@ -35,6 +40,7 @@ class ModalAlert(gtk.Window):
         height = gtk.gdk.screen_height() - offset * 2
         self.set_size_request(width, height)
         self.set_position(gtk.WIN_POS_CENTER_ALWAYS)
+        self.set_accept_focus(True)
         self.set_decorated(False)
         self.set_resizable(False)
         self.set_modal(True)
@@ -71,6 +77,16 @@ class ModalAlert(gtk.Window):
         self._vbox.pack_start(self._message, False)
         self._message.show()
 
+        self._space_bar = gtk.ProgressBar()
+        self._vbox.pack_start(self._space_bar, False)
+        self._space_bar.show()
+
+        advice = gtk.Label(_('Delete entries until this bar is empty'))
+        advice.modify_fg(gtk.STATE_NORMAL,
+                        style.COLOR_WHITE.get_gdk_color())
+        self._vbox.pack_start(advice, False)
+        advice.show()
+
         alignment = gtk.Alignment(xalign=0.5, yalign=0.5)
         self._vbox.pack_start(alignment, expand=False)
         alignment.show()
@@ -91,7 +107,13 @@ class ModalAlert(gtk.Window):
         self.window.set_accept_focus(True)
 
     def __show_journal_cb(self, button):
-        '''The opener will listen on the destroy signal
-        '''
-        self.destroy()
+        self.emit('show-journal')
+
+    def update_space_fraction(self, fraction):
+        if fraction > 1.0:
+            fraction = 1.0
+        elif fraction < 0.0:
+            fraction = 0.0
+
+        self._space_bar.set_fraction(fraction)
 
-- 
1.7.1