# -*- coding: utf-8 -*-

'''
Task Coach - Your friendly task manager
Copyright (C) 2004-2013 Task Coach developers <developers@taskcoach.org>
Copyright (C) 2008 Rob McMullen <rob.mcmullen@gmail.com>
Copyright (C) 2008 Thomas Sonne Olesen <tpo@sonnet.dk>

Task Coach is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.

Task Coach 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 General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.
'''

import math
import wx.lib.agw.piectrl
from taskcoachlib import command, widgets, domain, render
from taskcoachlib.domain import task, date
from taskcoachlib.gui import uicommand, menu, dialog
from taskcoachlib.i18n import _
from taskcoachlib.thirdparty.pubsub import pub
from taskcoachlib.thirdparty.wxScheduler import wxSCHEDULER_TODAY, wxFancyDrawer
from taskcoachlib.thirdparty import smartdatetimectrl as sdtc
from taskcoachlib.widgets import CalendarConfigDialog
import base
import inplace_editor
import mixin
import refresher 


class DueDateTimeCtrl(inplace_editor.DateTimeCtrl):
    def __init__(self, parent, wxId, item, column, owner, value, **kwargs):
        kwargs['relative'] = True
        kwargs['startDateTime'] = item.GetData().plannedStartDateTime()
        super(DueDateTimeCtrl, self).__init__(parent, wxId, item, column, owner, value, **kwargs)
        sdtc.EVT_TIME_CHOICES_CHANGE(self._dateTimeCtrl, self.OnChoicesChange)
        self._dateTimeCtrl.LoadChoices(item.GetData().settings.get('feature', 'sdtcspans'))

    def OnChoicesChange(self, event):
        self.item().GetData().settings.settext('feature', 'sdtcspans', event.GetValue())


class TaskViewerStatusMessages(object):
    template1 = _('Tasks: %d selected, %d visible, %d total')
    template2 = _('Status: %d overdue, %d late, %d inactive, %d completed')
    
    def __init__(self, viewer):
        super(TaskViewerStatusMessages, self).__init__()
        self.__viewer = viewer
        self.__presentation = viewer.presentation()
    
    def __call__(self):
        count = self.__presentation.observable(recursive=True).nrOfTasksPerStatus()
        return self.template1 % (len(self.__viewer.curselection()), 
                                 self.__viewer.nrOfVisibleTasks(), 
                                 self.__presentation.originalLength()), \
               self.template2 % (count[task.status.overdue], 
                                 count[task.status.late],
                                 count[task.status.inactive], 
                                 count[task.status.completed])


class BaseTaskViewer(mixin.SearchableViewerMixin,  # pylint: disable=W0223
                     mixin.FilterableViewerForTasksMixin,
                     base.TreeViewer):        
    def __init__(self, *args, **kwargs):
        super(BaseTaskViewer, self).__init__(*args, **kwargs)
        self.statusMessages = TaskViewerStatusMessages(self)
        self.__registerForAppearanceChanges()
        wx.CallAfter(self.__DisplayBalloon)

    def __DisplayBalloon(self):
        if self.toolbar.getToolIdByCommand('ViewerHideTasks_completed') != wx.ID_ANY and self.toolbar.IsShownOnScreen() and \
            hasattr(wx.GetTopLevelParent(self), 'AddBalloonTip'):
            wx.GetTopLevelParent(self).AddBalloonTip(self.settings, 'filtershiftclick', self.toolbar,
                        getRect=lambda: self.toolbar.GetToolRect(self.toolbar.getToolIdByCommand('ViewerHideTasks_completed')),
                        message=_('''Shift-click on a filter tool to see only tasks belonging to the corresponding status'''))

    def __registerForAppearanceChanges(self):
        for appearance in ('font', 'fgcolor', 'bgcolor', 'icon'):
            appearanceSettings = ['settings.%s.%s' % (appearance, setting) for setting in 'activetasks',\
                                  'inactivetasks', 'completedtasks', 'duesoontasks', 'overduetasks', 'latetasks'] 
            for appearanceSetting in appearanceSettings:
                pub.subscribe(self.onAppearanceSettingChange, appearanceSetting)
        self.registerObserver(self.onAttributeChanged_Deprecated,
                              eventType=task.Task.appearanceChangedEventType())
        pub.subscribe(self.onAttributeChanged, task.Task.prerequisitesChangedEventType())
        pub.subscribe(self.refresh, 'powermgt.on')

    def detach(self):
        super(BaseTaskViewer, self).detach()
        self.statusMessages = None # Break cycle

    def onAppearanceSettingChange(self, value):  # pylint: disable=W0613
        if self:
            wx.CallAfter(self.refresh)  # Let domain objects update appearance first
        # Show/hide status in toolbar may change too
        self.toolbar.loadPerspective(self.toolbar.perspective(), cache=False)

    def domainObjectsToView(self):
        return self.taskFile.tasks()

    def isShowingTasks(self): 
        return True

    def createFilter(self, taskList):
        tasks = domain.base.DeletedFilter(taskList)
        return super(BaseTaskViewer, self).createFilter(tasks)

    def nrOfVisibleTasks(self):
        # Make this overridable for viewers where the widget does not show all
        # items in the presentation, i.e. the widget does filtering on its own.
        return len(self.presentation())


class BaseTaskTreeViewer(BaseTaskViewer):  # pylint: disable=W0223
    defaultTitle = _('Tasks')
    defaultBitmap = 'led_blue_icon'
    
    def __init__(self, *args, **kwargs):
        super(BaseTaskTreeViewer, self).__init__(*args, **kwargs)
        if kwargs.get('doRefresh', True):
            self.secondRefresher = refresher.SecondRefresher(self,
                                                             task.Task.trackingChangedEventType())
            self.minuteRefresher = refresher.MinuteRefresher(self)
        else:
            self.secondRefresher = self.minuteRefresher = None
        
    def detach(self):
        super(BaseTaskTreeViewer, self).detach()
        if self.secondRefresher:
            self.secondRefresher.stopClock()
            self.secondRefresher.removeInstance()
            del self.secondRefresher
        if self.minuteRefresher:
            self.minuteRefresher.stopClock()
            del self.minuteRefresher
        
    def newItemDialog(self, *args, **kwargs):
        kwargs['categories'] = self.taskFile.categories().filteredCategories()
        return super(BaseTaskTreeViewer, self).newItemDialog(*args, **kwargs)
    
    def editItemDialog(self, items, bitmap, columnName='', 
                       items_are_new=False):
        if isinstance(items[0], task.Task):
            return super(BaseTaskTreeViewer, self).editItemDialog(items, bitmap, 
                columnName=columnName, items_are_new=items_are_new)
        else:
            return dialog.editor.EffortEditor(wx.GetTopLevelParent(self),
                items, self.settings, self.taskFile.efforts(), self.taskFile,  
                bitmap=bitmap, items_are_new=items_are_new)
            
    def itemEditorClass(self):
        return dialog.editor.TaskEditor
    
    def newItemCommandClass(self):
        return command.NewTaskCommand
    
    def newSubItemCommandClass(self):
        return command.NewSubTaskCommand
    
    def newSubItemCommand(self):
        kwargs = dict() 
        if self.__shouldPresetPlannedStartDateTime():
            kwargs['plannedStartDateTime'] = task.Task.suggestedPlannedStartDateTime()
        if self.__shouldPresetDueDateTime():
            kwargs['dueDateTime'] = task.Task.suggestedDueDateTime()
        if self.__shouldPresetActualStartDateTime():
            kwargs['actualStartDateTime'] = task.Task.suggestedActualStartDateTime()
        if self.__shouldPresetCompletionDateTime():
            kwargs['completionDateTime'] = task.Task.suggestedCompletionDateTime()
        if self.__shouldPresetReminderDateTime():
            kwargs['reminder'] = task.Task.suggestedReminderDateTime()
        # pylint: disable=W0142
        return self.newSubItemCommandClass()(self.presentation(), 
                                             self.curselection(), **kwargs)

    def __shouldPresetPlannedStartDateTime(self):
        return self.settings.get('view', 'defaultplannedstartdatetime').startswith('preset')
            
    def __shouldPresetDueDateTime(self):
        return self.settings.get('view', 'defaultduedatetime').startswith('preset')

    def __shouldPresetActualStartDateTime(self):
        return self.settings.get('view', 'defaultactualstartdatetime').startswith('preset')
    
    def __shouldPresetCompletionDateTime(self):
        return self.settings.get('view', 'defaultcompletiondatetime').startswith('preset')
            
    def __shouldPresetReminderDateTime(self):
        return self.settings.get('view', 'defaultreminderdatetime').startswith('preset')
           
    def deleteItemCommand(self):
        return command.DeleteTaskCommand(self.presentation(), self.curselection(),
                  shadow=self.settings.getboolean('feature', 'syncml'))    

    def createTaskPopupMenu(self):
        return menu.TaskPopupMenu(self.parent, self.settings,
                                  self.presentation(), self.taskFile.efforts(),
                                  self.taskFile.categories(), self)

    def createCreationToolBarUICommands(self):
        return (uicommand.TaskNew(taskList=self.presentation(),
                                  settings=self.settings),
                uicommand.NewSubItem(viewer=self),
                uicommand.TaskNewFromTemplateButton(taskList=self.presentation(),
                                                    settings=self.settings,
                                                    bitmap='newtmpl')) + \
            super(BaseTaskTreeViewer, self).createCreationToolBarUICommands()
    
    def createActionToolBarUICommands(self):
        uiCommands = (uicommand.TaskMarkInactive(settings=self.settings, viewer=self),
                      uicommand.TaskMarkActive(settings=self.settings, viewer=self),
                      uicommand.TaskMarkCompleted(settings=self.settings, viewer=self))
        if self.settings.getboolean('feature', 'effort'):
            uiCommands += (
                # EffortStart needs a reference to the original (task) list to
                # be able to stop tracking effort for tasks that are already 
                # being tracked, but that might be filtered in the viewer's 
                # presentation.
                None,
                uicommand.EffortStart(viewer=self, 
                                      taskList=self.taskFile.tasks()),
                uicommand.EffortStop(viewer=self,
                                     effortList=self.taskFile.efforts(),
                                     taskList=self.taskFile.tasks()))
        return uiCommands + super(BaseTaskTreeViewer, self).createActionToolBarUICommands()
    
    def createModeToolBarUICommands(self):
        hideUICommands = tuple([uicommand.ViewerHideTasks(taskStatus=status,
                                                          settings=self.settings,
                                                          viewer=self) \
                                for status in task.Task.possibleStatuses()])
        otherModeUICommands = super(BaseTaskTreeViewer, self).createModeToolBarUICommands()
        separator = (None,) if otherModeUICommands else ()
        return hideUICommands + separator + otherModeUICommands

    def iconName(self, item, isSelected):
        return item.selectedIcon(recursive=True) if isSelected else item.icon(recursive=True)

    def getItemTooltipData(self, task):  # pylint: disable=W0621
        if not self.settings.getboolean('view', 'descriptionpopups'):
            return []
        result = [(self.iconName(task, task in self.curselection()), 
                   [self.getItemText(task)])]
        if task.description():
            result.append((None, [line.rstrip('\n') for line in task.description().split('\n')]))
        if task.notes():
            result.append(('note_icon', sorted([note.subject() for note in task.notes()])))
        if task.attachments():
            result.append(('paperclip_icon',
                sorted([unicode(attachment) for attachment in task.attachments()])))
        return result

    def label(self, task):  # pylint: disable=W0621
        return self.getItemText(task)


class RootNode(object):
    def __init__(self, tasks):
        self.tasks = tasks
        
    def subject(self):
        return ''
    
    def children(self, recursive=False):
        if recursive:
            return self.tasks[:]
        else:
            return self.tasks.rootItems()

    # pylint: disable=W0613
    
    def foregroundColor(self, *args, **kwargs): 
        return None

    def backgroundColor(self, *args, **kwargs):
        return None
    
    def font(self, *args, **kwargs):
        return None

    def completed(self, *args, **kwargs):
        return False

    late = dueSoon = inactive = overdue = isBeingTracked = completed


class SquareMapRootNode(RootNode):
    def __getattr__(self, attr):
        def getTaskAttribute(recursive=True):
            if recursive:
                return max(sum((getattr(task, attr)(recursive=True) for task in self.children()),
                               self.__zero), 
                           self.__zero)
            else:
                return self.__zero

        self.__zero = date.TimeDelta() if attr in ('budget', 'budgetLeft', 'timeSpent') else 0  # pylint: disable=W0201
        return getTaskAttribute


class TimelineRootNode(RootNode):
    def children(self, recursive=False):
        children = super(TimelineRootNode, self).children(recursive)
        children.sort(key=lambda task: task.plannedStartDateTime())
        return children
    
    def parallel_children(self, recursive=False):
        return self.children(recursive)

    def sequential_children(self):
        return []

    def plannedStartDateTime(self, recursive=False):  # pylint: disable=W0613
        plannedStartDateTimes = [item.plannedStartDateTime(recursive=True) for item in self.parallel_children()]
        plannedStartDateTimes = [dt for dt in plannedStartDateTimes if dt != date.DateTime()]
        if not plannedStartDateTimes:
            plannedStartDateTimes.append(date.Now())
        return min(plannedStartDateTimes)
    
    def dueDateTime(self, recursive=False):  # pylint: disable=W0613
        dueDateTimes = [item.dueDateTime(recursive=True) for item in self.parallel_children()]
        dueDateTimes = [dt for dt in dueDateTimes if dt != date.DateTime()]
        if not dueDateTimes:
            dueDateTimes.append(date.Tomorrow())    
        return max(dueDateTimes)
    

class TimelineViewer(BaseTaskTreeViewer):
    defaultTitle = _('Timeline')
    defaultBitmap = 'timelineviewer'

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('settingsSection', 'timelineviewer')
        super(TimelineViewer, self).__init__(*args, **kwargs)
        for eventType in (task.Task.subjectChangedEventType(), 
            task.Task.plannedStartDateTimeChangedEventType(),
            task.Task.dueDateTimeChangedEventType(), 
            task.Task.completionDateTimeChangedEventType()):
            if eventType.startswith('pubsub'):
                pub.subscribe(self.onAttributeChanged, eventType)
            else:
                self.registerObserver(self.onAttributeChanged_Deprecated, 
                                      eventType)
        
    def createWidget(self):
        self.rootNode = TimelineRootNode(self.presentation())  # pylint: disable=W0201
        itemPopupMenu = self.createTaskPopupMenu()
        self._popupMenus.append(itemPopupMenu)
        return widgets.Timeline(self, self.rootNode, self.onSelect, self.onEdit,
                                itemPopupMenu)

    def onEdit(self, item):
        edit = uicommand.Edit(viewer=self)
        edit(item)
        
    def curselection(self):
        # Override curselection, because there is no need to translate indices
        # back to domain objects. Our widget already returns the selected domain
        # object itself.
        return self.widget.curselection()
    
    def bounds(self, item):
        times = [self.start(item), self.stop(item)]
        for child in self.parallel_children(item) + self.sequential_children(item):
            times.extend(self.bounds(child))
        times = [time for time in times if time is not None]
        return (min(times), max(times)) if times else []
 
    def start(self, item, recursive=False):
        try:
            start = item.plannedStartDateTime(recursive=recursive)
            if start == date.DateTime():
                return None
        except AttributeError:
            start = item.getStart()
        return start.toordinal()

    def stop(self, item, recursive=False):
        try:
            if item.completed():
                stop = item.completionDateTime(recursive=recursive)
            else:
                stop = item.dueDateTime(recursive=recursive)
            if stop == date.DateTime():
                return None   
            else:
                stop += date.ONE_DAY
        except AttributeError:
            stop = item.getStop()
            if not stop:
                return None
        return stop.toordinal() 

    def sequential_children(self, item):
        try:
            return item.efforts()
        except AttributeError:
            return []

    def parallel_children(self, item, recursive=False):
        try:
            children = [child for child in item.children(recursive=recursive) \
                        if child in self.presentation()]
            children.sort(key=lambda task: task.plannedStartDateTime())
            return children
        except AttributeError:
            return []

    def foreground_color(self, item, depth=0):  # pylint: disable=W0613
        return item.foregroundColor(recursive=True)
          
    def background_color(self, item, depth=0):  # pylint: disable=W0613
        return item.backgroundColor(recursive=True)
    
    def font(self, item, depth=0):  # pylint: disable=W0613
        return item.font(recursive=True)

    def icon(self, item, isSelected=False):
        bitmap = self.iconName(item, isSelected)
        return wx.ArtProvider_GetIcon(bitmap, wx.ART_MENU, (16, 16))
    
    def now(self):
        return date.Now().toordinal()
    
    def nowlabel(self):
        return _('Now')

    def getItemTooltipData(self, item):
        if not self.settings.getboolean('view', 'descriptionpopups'):
            result = []
        elif isinstance(item, task.Task):
            result = super(TimelineViewer, self).getItemTooltipData(item)
        else:
            result = [(None, [render.dateTimePeriod(item.getStart(), item.getStop(), humanReadable=True)])]
            if item.description(): 
                result.append((None, [line.rstrip('\n') for line in item.description().split('\n')]))     
        return result


class SquareTaskViewer(BaseTaskTreeViewer):
    defaultTitle = _('Task square map')
    defaultBitmap = 'squaremapviewer'

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('settingsSection', 'squaretaskviewer')
        self.__orderBy = 'revenue'
        self.__transformTaskAttribute = lambda x: x
        self.__zero = 0
        super(SquareTaskViewer, self).__init__(*args, **kwargs)
        self.orderBy(self.settings.get(self.settingsSection(), 'sortby'))
        pub.subscribe(self.on_order_by_changed, 
                      'settings.%s.sortby' % self.settingsSection())
        self.orderUICommand.setChoice(self.__orderBy)
        for eventType in (task.Task.subjectChangedEventType(),
            task.Task.dueDateTimeChangedEventType(),
            task.Task.plannedStartDateTimeChangedEventType(),
            task.Task.completionDateTimeChangedEventType()):
            if eventType.startswith('pubsub'):
                pub.subscribe(self.onAttributeChanged, eventType)
            else:
                self.registerObserver(self.onAttributeChanged_Deprecated, eventType)

    def curselectionIsInstanceOf(self, class_):
        return class_ == task.Task
    
    def createWidget(self):
        itemPopupMenu = self.createTaskPopupMenu()
        self._popupMenus.append(itemPopupMenu)
        return widgets.SquareMap(self, SquareMapRootNode(self.presentation()), 
            self.onSelect, uicommand.Edit(viewer=self), itemPopupMenu)
        
    def createModeToolBarUICommands(self):
        self.orderUICommand = uicommand.SquareTaskViewerOrderChoice(viewer=self,
                                                                    settings=self.settings)  # pylint: disable=W0201
        return super(SquareTaskViewer, self).createModeToolBarUICommands() + \
            (self.orderUICommand,)
        
    def hasModes(self):
        return True
    
    def getModeUICommands(self):
        return [_('Lay out tasks by'), None] + \
            [uicommand.SquareTaskViewerOrderByOption(menuText=menuText,
                                                     value=value, viewer=self, 
                                                     settings=self.settings)
             for (menuText, value) in zip(uicommand.SquareTaskViewerOrderChoice.choiceLabels,
                                          uicommand.SquareTaskViewerOrderChoice.choiceData)]
    
    def on_order_by_changed(self, value):
        self.orderBy(value)
        
    def orderBy(self, choice):
        if choice == self.__orderBy:
            return
        oldChoice = self.__orderBy
        self.__orderBy = choice
        try:
            oldEventType = getattr(task.Task, '%sChangedEventType' % oldChoice)()
        except AttributeError:
            oldEventType = 'task.%s' % oldChoice
        if oldEventType.startswith('pubsub'):
            try:
                pub.unsubscribe(self.onAttributeChanged, oldEventType)
            except pub.UndefinedSubtopic:
                pass  # Can happen on first call to orderBy
        else:
            self.removeObserver(self.onAttributeChanged_Deprecated, oldEventType)
        try:
            newEventType = getattr(task.Task, '%sChangedEventType' % choice)()
        except AttributeError:
            newEventType = 'task.%s' % choice
        if newEventType.startswith('pubsub'):
            pub.subscribe(self.onAttributeChanged, newEventType)
        else:
            self.registerObserver(self.onAttributeChanged_Deprecated, newEventType)
        if choice in ('budget', 'timeSpent'):
            self.__transformTaskAttribute = lambda timeSpent: timeSpent.milliseconds() / 1000
            self.__zero = date.TimeDelta()
        else:
            self.__transformTaskAttribute = lambda x: x
            self.__zero = 0
        self.refresh()
        
    def curselection(self):
        # Override curselection, because there is no need to translate indices
        # back to domain objects. Our widget already returns the selected domain
        # object itself.
        return self.widget.curselection()
    
    def nrOfVisibleTasks(self):
        return len([eachTask for eachTask in self.presentation() \
                    if getattr(eachTask, self.__orderBy)(recursive=True) > self.__zero])
        
    # SquareMap adapter methods:
    # pylint: disable=W0621
    
    def overall(self, task):
        return self.__transformTaskAttribute(max(getattr(task, self.__orderBy)(recursive=True),
                                                 self.__zero))
    
    def children_sum(self, children, parent):  # pylint: disable=W0613
        children_sum = sum((max(getattr(child, self.__orderBy)(recursive=True), self.__zero) for child in children \
                            if child in self.presentation()), self.__zero)
        return self.__transformTaskAttribute(max(children_sum, self.__zero))
    
    def empty(self, task):
        overall = self.overall(task)
        if overall:
            children_sum = self.children_sum(self.children(task), task)
            return max(self.__transformTaskAttribute(self.__zero), 
                       (overall - children_sum)) / float(overall)
        return 0
    
    def getItemText(self, task):
        text = super(SquareTaskViewer, self).getItemText(task)
        value = self.render(getattr(task, self.__orderBy)(recursive=False))
        return '%s (%s)' % (text, value) if value else text

    def value(self, task, parent=None):  # pylint: disable=W0613
        return self.overall(task)

    def foreground_color(self, task, depth):  # pylint: disable=W0613
        return task.foregroundColor(recursive=True)
        
    def background_color(self, task, depth):  # pylint: disable=W0613
        red = blue = 255 - (depth * 3) % 100
        green = 255 - (depth * 2) % 100
        color = wx.Color(red, green, blue)
        return task.backgroundColor(recursive=True) or color
    
    def font(self, task, depth):  # pylint: disable=W0613
        return task.font(recursive=True)

    def icon(self, task, isSelected):
        bitmap = self.iconName(task, isSelected) or 'led_blue_icon'
        return wx.ArtProvider_GetIcon(bitmap, wx.ART_MENU, (16, 16))

    # Helper methods
    
    renderer = dict(budget=render.budget, timeSpent=render.timeSpent, 
                    fixedFee=render.monetaryAmount, 
                    revenue=render.monetaryAmount,
                    priority=render.priority)
    
    def render(self, value):
        return self.renderer[self.__orderBy](value)


class CalendarViewer(mixin.AttachmentDropTargetMixin,
                     mixin.SortableViewerForTasksMixin,
                     BaseTaskTreeViewer):
    defaultTitle = _('Calendar')
    defaultBitmap = 'calendar_icon'

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('settingsSection', 'calendarviewer')
        kwargs['doRefresh'] = False
        super(CalendarViewer, self).__init__(*args, **kwargs)

        start = self.settings.get(self.settingsSection(), 'viewdate')
        if start:
            dt = wx.DateTime.Now()
            dt.ParseDateTime(start)
            self.widget.SetDate(dt)

        self.onWeekStartChanged(self.settings.gettext('view', 'weekstart'))
        self.onWorkingHourChanged()

        self.reconfig()
        self.widget.SetPeriodWidth(self.settings.getint(self.settingsSection(), 
                                                        'periodwidth'))

        for eventType in ('start', 'end'):
            pub.subscribe(self.onWorkingHourChanged, 
                          'settings.view.efforthour%s' % eventType)
        pub.subscribe(self.onWeekStartChanged, 'settings.view.weekstartmonday')

        # pylint: disable=E1101
        for eventType in (task.Task.subjectChangedEventType(), 
                          task.Task.plannedStartDateTimeChangedEventType(),
                          task.Task.dueDateTimeChangedEventType(), 
                          task.Task.completionDateTimeChangedEventType(),
                          task.Task.attachmentsChangedEventType(),
                          task.Task.notesChangedEventType(),
                          task.Task.trackingChangedEventType(),
                          task.Task.percentageCompleteChangedEventType()):
            if eventType.startswith('pubsub'):
                pub.subscribe(self.onAttributeChanged, eventType)
            else:
                self.registerObserver(self.onAttributeChanged_Deprecated, 
                                      eventType)
        date.Scheduler().schedule_interval(self.atMidnight, days=1)

    def detach(self):
        super(CalendarViewer, self).detach()
        date.Scheduler().unschedule(self.atMidnight)

    def isTreeViewer(self):
        return False

    def onEverySecond(self, event):  # pylint: disable=W0221,W0613
        pass  # Too expensive

    def atMidnight(self):
        if not self.settings.get(self.settingsSection(), 'viewdate'):
            # User has selected the "current" date/time; it may have
            # changed now
            self.SetViewType(wxSCHEDULER_TODAY)

    def onWorkingHourChanged(self, value=None):  # pylint: disable=W0613
        self.widget.SetWorkHours(self.settings.getint('view', 'efforthourstart'),
                                 self.settings.getint('view', 'efforthourend'))
        
    def onWeekStartChanged(self, value):
        assert value in ('monday', 'sunday')
        if value == 'monday':
            self.widget.SetWeekStartMonday()
        else:
            self.widget.SetWeekStartSunday()

    def createWidget(self):
        itemPopupMenu = self.createTaskPopupMenu()
        self._popupMenus.append(itemPopupMenu)
        widget = widgets.Calendar(self, self.presentation(), self.iconName, 
                                  self.onSelect, self.onEdit, self.onCreate, 
                                  self.onChangeConfig, itemPopupMenu,
                                  **self.widgetCreationKeywordArguments())

        if self.settings.getboolean('calendarviewer', 'gradient'):
            # If called directly, we crash with a Cairo assert failing...
            wx.CallAfter(widget.SetDrawer, wxFancyDrawer)

        return widget

    def onChangeConfig(self):
        self.settings.set(self.settingsSection(), 'periodwidth', 
                          str(self.widget.GetPeriodWidth()))

    def onEdit(self, item):
        edit = uicommand.Edit(viewer=self)
        edit(item)

    def onCreate(self, dateTime, show=True):
        plannedStartDateTime = dateTime
        dueDateTime = dateTime.endOfDay() if dateTime == dateTime.startOfDay() else dateTime
        create = uicommand.TaskNew(taskList=self.presentation(), 
                                   settings=self.settings,
                                   taskKeywords=dict(plannedStartDateTime=plannedStartDateTime, 
                                                     dueDateTime=dueDateTime))
        return create(event=None, show=show)

    def createModeToolBarUICommands(self):
        return super(CalendarViewer, self).createModeToolBarUICommands() + \
            (None, uicommand.CalendarViewerConfigure(viewer=self),
             uicommand.CalendarViewerPreviousPeriod(viewer=self),
             uicommand.CalendarViewerToday(viewer=self),
             uicommand.CalendarViewerNextPeriod(viewer=self))

    def SetViewType(self, type_):
        self.widget.SetViewType(type_)
        dt = self.widget.GetDate()
        now = wx.DateTime.Today()
        if (dt.GetYear(), dt.GetMonth(), dt.GetDay()) == (now.GetYear(), now.GetMonth(), now.GetDay()):
            toSave = ''
        else:
            toSave = dt.Format()
        self.settings.set(self.settingsSection(), 'viewdate', toSave)

    # We need to override these because BaseTaskTreeViewer is a tree viewer, but
    # CalendarViewer is not. There is probably a better solution...

    def isAnyItemExpandable(self):
        return False

    def isAnyItemCollapsable(self):
        return False

    def reconfig(self):
        self.widget.Freeze()
        try:
            self.widget.SetPeriodCount(self.settings.getint(self.settingsSection(), 'periodcount'))
            self.widget.SetViewType(self.settings.getint(self.settingsSection(), 'viewtype'))
            self.widget.SetStyle(self.settings.getint(self.settingsSection(), 'vieworientation'))
            self.widget.SetShowNoStartDate(self.settings.getboolean(self.settingsSection(), 'shownostart'))
            self.widget.SetShowNoDueDate(self.settings.getboolean(self.settingsSection(), 'shownodue'))
            self.widget.SetShowUnplanned(self.settings.getboolean(self.settingsSection(), 'showunplanned'))
            self.widget.SetShowNow(self.settings.getboolean(self.settingsSection(), 'shownow'))

            hcolor = self.settings.get(self.settingsSection(), 'highlightcolor')
            if hcolor:
                highlightColor = wx.Colour(*tuple([int(c) for c in hcolor.split(',')]))
                self.widget.SetHighlightColor(highlightColor)
            self.widget.RefreshAllItems(0)
        finally:
            self.widget.Thaw()

    def configure(self):
        dialog = CalendarConfigDialog(self.settings, self.settingsSection(), 
                                      self, 
                                      title=_('Calendar viewer configuration'))
        dialog.CentreOnParent()
        if dialog.ShowModal() == wx.ID_OK:
            self.reconfig()

    def GetPrintout(self):
        return self.widget.GetPrintout()


class TaskViewer(mixin.AttachmentDropTargetMixin,  # pylint: disable=W0223
                 mixin.SortableViewerForTasksMixin, 
                 mixin.NoteColumnMixin, mixin.AttachmentColumnMixin,
                 base.SortableViewerWithColumns, BaseTaskTreeViewer):

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('settingsSection', 'taskviewer')
        super(TaskViewer, self).__init__(*args, **kwargs)
        if self.isVisibleColumnByName('timeLeft'):
            self.minuteRefresher.startClock()
        pub.subscribe(self.onTreeListModeChanged, 
                      'settings.%s.treemode' % self.settingsSection())

    def isTreeViewer(self):
        # We first ask our presentation what the mode is because 
        # ConfigParser.getboolean is a relatively expensive method. However,
        # when initializing, the presentation might not be created yet. So in
        # that case we get an AttributeError and we use the settings.
        try:
            return self.presentation().treeMode()
        except AttributeError:
            return self.settings.getboolean(self.settingsSection(), 'treemode')

    def showColumn(self, column, show=True, *args, **kwargs):
        super(TaskViewer, self).showColumn(column, show, *args, **kwargs)
        if column.name() == 'timeLeft':
            if show:
                self.minuteRefresher.startClock()
            else:
                self.minuteRefresher.stopClock()
                            
    def curselectionIsInstanceOf(self, class_):
        return class_ == task.Task
    
    def createWidget(self):
        imageList = self.createImageList()  # Has side-effects
        self._columns = self._createColumns()
        itemPopupMenu = self.createTaskPopupMenu()
        columnPopupMenu = self.createColumnPopupMenu()
        self._popupMenus.extend([itemPopupMenu, columnPopupMenu])
        widget = widgets.TreeListCtrl(self, self.columns(), self.onSelect, 
            uicommand.Edit(viewer=self),
            uicommand.TaskDragAndDrop(taskList=self.presentation(), 
                                      viewer=self),
            itemPopupMenu, columnPopupMenu,
            **self.widgetCreationKeywordArguments())
        widget.AssignImageList(imageList)  # pylint: disable=E1101
        widget.Bind(wx.EVT_TREE_BEGIN_LABEL_EDIT, self.onBeginEdit)
        widget.Bind(wx.EVT_TREE_END_LABEL_EDIT, self.onEndEdit)
        return widget
    
    def onBeginEdit(self, event):
        ''' Make sure only the non-recursive part of the subject can be
            edited inline. '''
        event.Skip()
        if not self.isTreeViewer():
            # Make sure the text control only shows the non-recursive subject
            # by temporarily changing the item text into the non-recursive
            # subject. When the editing ends, we change the item text back into
            # the recursive subject. See onEndEdit.
            treeItem = event.GetItem()
            editedTask = self.widget.GetItemPyData(treeItem)
            self.widget.SetItemText(treeItem, editedTask.subject())
            
    def onEndEdit(self, event):
        ''' Make sure only the non-recursive part of the subject can be
            edited inline. '''
        event.Skip()
        if not self.isTreeViewer():
            # Restore the recursive subject. Here we don't care whether users
            # actually changed the subject. If they did, the subject will 
            # be updated via the regular notification mechanism.
            treeItem = event.GetItem()
            editedTask = self.widget.GetItemPyData(treeItem)
            self.widget.SetItemText(treeItem, 
                                    editedTask.subject(recursive=True))
    
    def _createColumns(self):
        kwargs = dict(renderDescriptionCallback=lambda task: task.description(),
                      resizeCallback=self.onResizeColumn)
        # pylint: disable=E1101,W0142
        columns = [widgets.Column('subject', _('Subject'), 
                task.Task.subjectChangedEventType(), 
                task.Task.completionDateTimeChangedEventType(),
                task.Task.dueDateTimeChangedEventType(),
                task.Task.actualStartDateTimeChangedEventType(),
                task.Task.plannedStartDateTimeChangedEventType(),
                task.Task.trackingChangedEventType(),
                sortCallback=uicommand.ViewerSortByCommand(viewer=self,
                    value='subject'),
                width=self.getColumnWidth('subject'), 
                imageIndicesCallback=self.subjectImageIndices,
                renderCallback=self.renderSubject, 
                editCallback=self.onEditSubject, 
                editControl=inplace_editor.SubjectCtrl, **kwargs)] + \
            [widgets.Column('description', _('Description'), 
                task.Task.descriptionChangedEventType(), 
                sortCallback=uicommand.ViewerSortByCommand(viewer=self,
                    value='description'),
                renderCallback=lambda task: task.description(), 
                width=self.getColumnWidth('description'),  
                editCallback=self.onEditDescription, 
                editControl=inplace_editor.DescriptionCtrl, **kwargs)] + \
            [widgets.Column('attachments', _('Attachments'), 
                task.Task.attachmentsChangedEventType(), 
                width=self.getColumnWidth('attachments'),
                alignment=wx.LIST_FORMAT_LEFT,
                imageIndicesCallback=self.attachmentImageIndices,
                headerImageIndex=self.imageIndex['paperclip_icon'],
                renderCallback=lambda task: '', **kwargs)]
        if self.settings.getboolean('feature', 'notes'):
            columns.append(widgets.Column('notes', _('Notes'), 
                task.Task.notesChangedEventType(),
                width=self.getColumnWidth('notes'),
                alignment=wx.LIST_FORMAT_LEFT,
                imageIndicesCallback=self.noteImageIndices,
                headerImageIndex=self.imageIndex['note_icon'],
                renderCallback=lambda task: '', **kwargs))
        columns.extend(
            [widgets.Column('categories', _('Categories'), 
                task.Task.categoryAddedEventType(), 
                task.Task.categoryRemovedEventType(), 
                task.Task.categorySubjectChangedEventType(),
                task.Task.expansionChangedEventType(),
                sortCallback=uicommand.ViewerSortByCommand(viewer=self,
                                                           value='categories'),
                width=self.getColumnWidth('categories'),
                renderCallback=self.renderCategories, **kwargs),
             widgets.Column('prerequisites', _('Prerequisites'),
                task.Task.prerequisitesChangedEventType(), 
                task.Task.expansionChangedEventType(),
                sortCallback=uicommand.ViewerSortByCommand(viewer=self,
                                                           value='prerequisites'),
                renderCallback=self.renderPrerequisites,
                width=self.getColumnWidth('prerequisites'), **kwargs),
             widgets.Column('dependencies', _('Dependents'),
                task.Task.dependenciesChangedEventType(), 
                task.Task.expansionChangedEventType(),
                sortCallback=uicommand.ViewerSortByCommand(viewer=self,
                                                           value='dependencies'),
                renderCallback=self.renderDependencies,
                width=self.getColumnWidth('dependencies'), **kwargs)])

        for name, columnHeader, editCtrl, editCallback, eventTypes in [
            ('plannedStartDateTime', _('Planned start date'), 
             inplace_editor.DateTimeCtrl, self.onEditPlannedStartDateTime, []),
            ('dueDateTime', _('Due date'), DueDateTimeCtrl, 
             self.onEditDueDateTime, [task.Task.expansionChangedEventType()]),
            ('actualStartDateTime', _('Actual start date'), 
             inplace_editor.DateTimeCtrl, self.onEditActualStartDateTime, 
             [task.Task.expansionChangedEventType()]),
            ('completionDateTime', _('Completion date'), 
             inplace_editor.DateTimeCtrl, self.onEditCompletionDateTime, 
             [task.Task.expansionChangedEventType()])]:
            renderCallback = getattr(self, 'render%s' % \
                                     (name[0].capitalize() + name[1:]))
            columns.append(widgets.Column(name, columnHeader,  
                sortCallback=uicommand.ViewerSortByCommand(viewer=self, 
                                                           value=name),
                renderCallback=renderCallback, width=self.getColumnWidth(name),
                alignment=wx.LIST_FORMAT_RIGHT, editControl=editCtrl, 
                editCallback=editCallback, settings=self.settings, *eventTypes, 
                **kwargs))

        effortOn = self.settings.getboolean('feature', 'effort')
        dependsOnEffortFeature = ['budget', 'timeSpent', 'budgetLeft',
                                  'hourlyFee', 'fixedFee', 'revenue']
            
        for name, columnHeader, editCtrl, editCallback, eventTypes in [        
            ('percentageComplete', _('% complete'), 
             inplace_editor.PercentageCtrl, self.onEditPercentageComplete, 
             [task.Task.expansionChangedEventType(), 
              task.Task.percentageCompleteChangedEventType()]),
            ('timeLeft', _('Time left'), None, None, 
             [task.Task.expansionChangedEventType(), 'task.timeLeft']),
            ('recurrence', _('Recurrence'), None, None, 
             [task.Task.expansionChangedEventType(), 
              task.Task.recurrenceChangedEventType()]),
            ('budget', _('Budget'), inplace_editor.BudgetCtrl, 
             self.onEditBudget, [task.Task.expansionChangedEventType(), 
                                 task.Task.budgetChangedEventType()]),
            ('timeSpent', _('Time spent'), None, None, 
             [task.Task.expansionChangedEventType(), 
              task.Task.timeSpentChangedEventType()]),
            ('budgetLeft', _('Budget left'), None, None, 
             [task.Task.expansionChangedEventType(), 
              task.Task.budgetLeftChangedEventType()]),            
            ('priority', _('Priority'), inplace_editor.PriorityCtrl, 
             self.onEditPriority, [task.Task.expansionChangedEventType(), 
                                   task.Task.priorityChangedEventType()]),
            ('hourlyFee', _('Hourly fee'), inplace_editor.AmountCtrl, 
             self.onEditHourlyFee, [task.Task.hourlyFeeChangedEventType()]),
            ('fixedFee', _('Fixed fee'), inplace_editor.AmountCtrl, 
             self.onEditFixedFee, [task.Task.expansionChangedEventType(), 
                                   task.Task.fixedFeeChangedEventType()]),
            ('revenue', _('Revenue'), None, None, 
             [task.Task.expansionChangedEventType(), 
              task.Task.revenueChangedEventType()])]:
            if (name in dependsOnEffortFeature and effortOn) or name not in dependsOnEffortFeature:
                renderCallback = getattr(self, 'render%s' % \
                                         (name[0].capitalize() + name[1:]))
                columns.append(widgets.Column(name, columnHeader,  
                    sortCallback=uicommand.ViewerSortByCommand(viewer=self, 
                                                               value=name),
                    renderCallback=renderCallback, 
                    width=self.getColumnWidth(name),
                    alignment=wx.LIST_FORMAT_RIGHT, editControl=editCtrl, 
                    editCallback=editCallback, *eventTypes, **kwargs))
                
        columns.append(widgets.Column('reminder', _('Reminder'), 
            sortCallback=uicommand.ViewerSortByCommand(viewer=self, 
                                                       value='reminder'),
            renderCallback=self.renderReminder, 
            width=self.getColumnWidth('reminder'),
            alignment=wx.LIST_FORMAT_RIGHT, 
            editControl=inplace_editor.DateTimeCtrl,
            editCallback=self.onEditReminderDateTime, settings=self.settings,
            *[task.Task.expansionChangedEventType(), 
              task.Task.reminderChangedEventType()], **kwargs))
        columns.append(widgets.Column('creationDateTime', _('Creation date'),
            width=self.getColumnWidth('creationDateTime'),
            renderCallback=self.renderCreationDateTime,
            sortCallback=uicommand.ViewerSortByCommand(viewer=self, 
                                                       value='creationDateTime'),
            **kwargs))
        columns.append(widgets.Column('modificationDateTime', 
                                      _('Modification date'),
            width=self.getColumnWidth('modificationDateTime'),
            renderCallback=self.renderModificationDateTime,
            sortCallback=uicommand.ViewerSortByCommand(viewer=self, 
                                                       value='modificationDateTime'),
            *task.Task.modificationEventTypes(), **kwargs))
        return columns
    
    def createColumnUICommands(self):
        commands = [
            uicommand.ToggleAutoColumnResizing(viewer=self,
                                               settings=self.settings),
            None,
            (_('&Dates'),
             uicommand.ViewColumns(menuText=_('&All date columns'),
                helpText=_('Show/hide all date-related columns'),
                setting=['plannedStartDateTime', 'dueDateTime', 'timeLeft', 
                         'actualStartDateTime', 'completionDateTime', 
                         'recurrence'],
                viewer=self),
             None,
             uicommand.ViewColumn(menuText=_('&Planned start date'),
                 helpText=_('Show/hide planned start date column'),
                 setting='plannedStartDateTime', viewer=self),
             uicommand.ViewColumn(menuText=_('&Due date'),
                 helpText=_('Show/hide due date column'),
                 setting='dueDateTime', viewer=self),
             uicommand.ViewColumn(menuText=_('&Actual start date'),
                helpText=_('Show/hide actual start date column'),
                setting='actualStartDateTime', viewer=self),
             uicommand.ViewColumn(menuText=_('&Completion date'),
                 helpText=_('Show/hide completion date column'),
                 setting='completionDateTime', viewer=self),
             uicommand.ViewColumn(menuText=_('&Time left'),
                 helpText=_('Show/hide time left column'),
                 setting='timeLeft', viewer=self),
             uicommand.ViewColumn(menuText=_('&Recurrence'),
                 helpText=_('Show/hide recurrence column'),
                 setting='recurrence', viewer=self))]
        if self.settings.getboolean('feature', 'effort'):
            commands.extend([
                (_('&Budget'),
                 uicommand.ViewColumns(menuText=_('&All budget columns'),
                     helpText=_('Show/hide all budget-related columns'),
                     setting=['budget', 'timeSpent', 'budgetLeft'],
                     viewer=self),
                 None,
                 uicommand.ViewColumn(menuText=_('&Budget'),
                     helpText=_('Show/hide budget column'),
                     setting='budget', viewer=self),
                 uicommand.ViewColumn(menuText=_('&Time spent'),
                     helpText=_('Show/hide time spent column'),
                     setting='timeSpent', viewer=self),
                 uicommand.ViewColumn(menuText=_('&Budget left'),
                     helpText=_('Show/hide budget left column'),
                     setting='budgetLeft', viewer=self),
                ),
                (_('&Financial'),
                 uicommand.ViewColumns(menuText=_('&All financial columns'),
                     helpText=_('Show/hide all finance-related columns'),
                     setting=['hourlyFee', 'fixedFee', 'revenue'],
                     viewer=self),
                 None,
                 uicommand.ViewColumn(menuText=_('&Hourly fee'),
                     helpText=_('Show/hide hourly fee column'),
                     setting='hourlyFee', viewer=self),
                 uicommand.ViewColumn(menuText=_('&Fixed fee'),
                     helpText=_('Show/hide fixed fee column'),
                     setting='fixedFee', viewer=self),
                 uicommand.ViewColumn(menuText=_('&Revenue'),
                     helpText=_('Show/hide revenue column'),
                     setting='revenue', viewer=self))])
        commands.extend([
            uicommand.ViewColumn(menuText=_('&Description'),
                helpText=_('Show/hide description column'),
                setting='description', viewer=self),
            uicommand.ViewColumn(menuText=_('&Prerequisites'),
                 helpText=_('Show/hide prerequisites column'),
                 setting='prerequisites', viewer=self),
            uicommand.ViewColumn(menuText=_('&Dependents'),
                 helpText=_('Show/hide dependents column'),
                 setting='dependencies', viewer=self),
             uicommand.ViewColumn(menuText=_('&Percentage complete'),
                 helpText=_('Show/hide percentage complete column'),
                 setting='percentageComplete', viewer=self),
            uicommand.ViewColumn(menuText=_('&Attachments'),
                helpText=_('Show/hide attachment column'),
                setting='attachments', viewer=self)])
        if self.settings.getboolean('feature', 'notes'):
            commands.append(
                uicommand.ViewColumn(menuText=_('&Notes'),
                    helpText=_('Show/hide notes column'),
                    setting='notes', viewer=self))
        commands.extend([
            uicommand.ViewColumn(menuText=_('&Categories'),
                helpText=_('Show/hide categories column'),
                setting='categories', viewer=self),
            uicommand.ViewColumn(menuText=_('&Priority'),
                helpText=_('Show/hide priority column'),
                setting='priority', viewer=self),
            uicommand.ViewColumn(menuText=_('&Reminder'),
                helpText=_('Show/hide reminder column'),
                setting='reminder', viewer=self),
            uicommand.ViewColumn(menuText=_('&Creation date'),
                helpText=_('Show/hide creation date column'),
                setting='creationDateTime', viewer=self),
            uicommand.ViewColumn(menuText=_('&Modification date'),
                helpText=_('Show/hide last modification date column'),
                setting='modificationDateTime', viewer=self)])
        return commands

    def createModeToolBarUICommands(self):
        treeOrListUICommand = uicommand.TaskViewerTreeOrListChoice(viewer=self,
                                                                   settings=self.settings)  # pylint: disable=W0201 
        return super(TaskViewer, self).createModeToolBarUICommands() + \
            (treeOrListUICommand,)
            
    def hasModes(self):
        return True
    
    def getModeUICommands(self):
        return [_('Show tasks as'), None] + \
            [uicommand.TaskViewerTreeOrListOption(menuText=menuText, value=value,
                                                  viewer=self, settings=self.settings)
             for (menuText, value) in zip(uicommand.TaskViewerTreeOrListChoice.choiceLabels,
                                          uicommand.TaskViewerTreeOrListChoice.choiceData)]

    def createColumnPopupMenu(self):
        return menu.ColumnPopupMenu(self)
                    
    def setSortByTaskStatusFirst(self, *args, **kwargs):  # pylint: disable=W0221
        super(TaskViewer, self).setSortByTaskStatusFirst(*args, **kwargs)
        self.showSortOrder()
        
    def getSortOrderImage(self):
        sortOrderImage = super(TaskViewer, self).getSortOrderImage()
        if self.isSortByTaskStatusFirst():  # pylint: disable=E1101
            sortOrderImage = sortOrderImage.rstrip('icon') + 'with_status_icon'
        return sortOrderImage

    def setSearchFilter(self, searchString, *args, **kwargs):  # pylint: disable=W0221
        super(TaskViewer, self).setSearchFilter(searchString, *args, **kwargs)
        if searchString:
            self.expandAll()  # pylint: disable=E1101      

    def onTreeListModeChanged(self, value):
        self.presentation().setTreeMode(value)
        
    # pylint: disable=W0621
    
    def renderSubject(self, task):
        return task.subject(recursive=not self.isTreeViewer())
    
    def renderPlannedStartDateTime(self, task, humanReadable=True):
        return self.renderedValue(task, task.plannedStartDateTime,
                                  lambda x: render.dateTime(x, humanReadable=humanReadable))
    
    def renderDueDateTime(self, task, humanReadable=True):
        return self.renderedValue(task, task.dueDateTime,
                                  lambda x: render.dateTime(x, humanReadable=humanReadable))

    def renderActualStartDateTime(self, task, humanReadable=True):
        return self.renderedValue(task, task.actualStartDateTime, 
                                  lambda x: render.dateTime(x, humanReadable=humanReadable))

    def renderCompletionDateTime(self, task, humanReadable=True):
        return self.renderedValue(task, task.completionDateTime, 
                                  lambda x: render.dateTime(x, humanReadable=humanReadable))

    def renderRecurrence(self, task):
        return self.renderedValue(task, task.recurrence, render.recurrence)
    
    def renderPrerequisites(self, task):
        return self.renderSubjectsOfRelatedItems(task, task.prerequisites)
    
    def renderDependencies(self, task):
        return self.renderSubjectsOfRelatedItems(task, task.dependencies)
    
    def renderTimeLeft(self, task):
        return self.renderedValue(task, task.timeLeft, render.timeLeft, 
                                  task.completed())
        
    def renderTimeSpent(self, task):
        return self.renderedValue(task, task.timeSpent, render.timeSpent)

    def renderBudget(self, task):
        return self.renderedValue(task, task.budget, render.budget)

    def renderBudgetLeft(self, task):
        return self.renderedValue(task, task.budgetLeft, render.budget)

    def renderRevenue(self, task):
        return self.renderedValue(task, task.revenue, render.monetaryAmount)
    
    def renderHourlyFee(self, task):
        # hourlyFee has no recursive value
        return render.monetaryAmount(task.hourlyFee())  
    
    def renderFixedFee(self, task):
        return self.renderedValue(task, task.fixedFee, render.monetaryAmount)

    def renderPercentageComplete(self, task):
        return self.renderedValue(task, task.percentageComplete, 
                                  render.percentage)

    def renderPriority(self, task):
        return self.renderedValue(task, task.priority, render.priority) + ' '
    
    def renderReminder(self, task, humanReadable=True):
        return self.renderedValue(task, task.reminder,
                                  lambda x: render.dateTime(x, humanReadable=humanReadable))
    
    def renderedValue(self, item, getValue, renderValue, *extraRenderArgs):
        value = getValue(recursive=False)
        template = '%s'
        if self.isItemCollapsed(item):
            recursiveValue = getValue(recursive=True)
            if value != recursiveValue:
                value = recursiveValue
                template = '(%s)'
        return template % renderValue(value, *extraRenderArgs)
    
    def onEditPlannedStartDateTime(self, item, newValue):
        keep_delta = self.settings.get('view', 'datestied') == 'startdue'
        command.EditPlannedStartDateTimeCommand(items=[item], 
                                                newValue=newValue, 
                                                keep_delta=keep_delta).do()
        
    def onEditDueDateTime(self, item, newValue):       
        keep_delta = self.settings.get('view', 'datestied') == 'duestart'
        command.EditDueDateTimeCommand(items=[item], newValue=newValue,
                                       keep_delta=keep_delta).do()

    def onEditActualStartDateTime(self, item, newValue):
        command.EditActualStartDateTimeCommand(items=[item], 
                                               newValue=newValue).do()
        
    def onEditCompletionDateTime(self, item, newValue):
        command.EditCompletionDateTimeCommand(items=[item], 
                                              newValue=newValue).do()
        
    def onEditPercentageComplete(self, item, newValue):
        command.EditPercentageCompleteCommand(items=[item], 
                                              newValue=newValue).do()  # pylint: disable=E1101
        
    def onEditBudget(self, item, newValue):
        command.EditBudgetCommand(items=[item], newValue=newValue).do()
        
    def onEditPriority(self, item, newValue):
        command.EditPriorityCommand(items=[item], newValue=newValue).do()
        
    def onEditReminderDateTime(self, item, newValue):
        command.EditReminderDateTimeCommand(items=[item], 
                                            newValue=newValue).do()
        
    def onEditHourlyFee(self, item, newValue):
        command.EditHourlyFeeCommand(items=[item], newValue=newValue).do()
        
    def onEditFixedFee(self, item, newValue):
        command.EditFixedFeeCommand(items=[item], newValue=newValue).do()

    def onEverySecond(self, event):
        # Only update when a column is visible that changes every second 
        if any([self.isVisibleColumnByName(column) for column in 'timeSpent', 
               'budgetLeft', 'revenue']):
            super(TaskViewer, self).onEverySecond(event)

    def getRootItems(self):
        ''' If the viewer is in tree mode, return the real root items. If the
            viewer is in list mode, return all items. '''
        return super(TaskViewer, self).getRootItems() if \
            self.isTreeViewer() else self.presentation()
    
    def getItemParent(self, item):
        return super(TaskViewer, self).getItemParent(item) if \
            self.isTreeViewer() else None

    def children(self, item=None):
        return super(TaskViewer, self).children(item) if \
            (self.isTreeViewer() or item is None) else []


class CheckableTaskViewer(TaskViewer):  # pylint: disable=W0223
    def createWidget(self):
        imageList = self.createImageList()  # Has side-effects
        self._columns = self._createColumns()
        itemPopupMenu = self.createTaskPopupMenu()
        columnPopupMenu = self.createColumnPopupMenu()
        self._popupMenus.extend([itemPopupMenu, columnPopupMenu])
        widget = widgets.CheckTreeCtrl(self, self.columns(), self.onSelect,
            self.onCheck, uicommand.Edit(viewer=self),
            uicommand.TaskDragAndDrop(taskList=self.presentation(), 
                                      viewer=self),
            itemPopupMenu, columnPopupMenu,
            **self.widgetCreationKeywordArguments())
        widget.AssignImageList(imageList)  # pylint: disable=E1101
        return widget    
    
    def onCheck(self, event):
        pass
    
    def getIsItemChecked(self, task):  # pylint: disable=W0613,W0621
        return False
    
    def getItemParentHasExclusiveChildren(self, task):  # pylint: disable=W0613,W0621
        return False
    
    
class TaskStatsViewer(BaseTaskViewer):  # pylint: disable=W0223
    defaultTitle = _('Task statistics')
    defaultBitmap = 'charts_icon'

    def __init__(self, *args, **kwargs):
        kwargs.setdefault('settingsSection', 'taskstatsviewer')
        super(TaskStatsViewer, self).__init__(*args, **kwargs)
        pub.subscribe(self.onPieChartAngleChanged, 
                      'settings.%s.piechartangle' % self.settingsSection())
        
    def createWidget(self):
        widget = wx.lib.agw.piectrl.PieCtrl(self)
        widget.SetShowEdges(False)
        widget.SetHeight(20)
        self.initLegend(widget)
        for dummy in task.Task.possibleStatuses():
            widget._series.append(wx.lib.agw.piectrl.PiePart(1))  # pylint: disable=W0212
        return widget

    def createClipboardToolBarUICommands(self):
        return ()
    
    def createEditToolBarUICommands(self):
        return ()
    
    def createCreationToolBarUICommands(self):
        return (uicommand.TaskNew(taskList=self.presentation(),
                                  settings=self.settings),
                uicommand.TaskNewFromTemplateButton(taskList=self.presentation(),
                                                    settings=self.settings,
                                                    bitmap='newtmpl'))
        
    def createActionToolBarUICommands(self):
        return tuple([uicommand.ViewerHideTasks(taskStatus=status,
                                                settings=self.settings,
                                                viewer=self) \
                            for status in task.Task.possibleStatuses()]) + \
               (uicommand.ViewerPieChartAngle(viewer=self, 
                                              settings=self.settings),)

    def initLegend(self, widget):
        legend = widget.GetLegend()
        legend.SetTransparent(False)
        legend.SetBackColour(wx.WHITE)
        legend.SetLabelFont(wx.SystemSettings.GetFont(wx.SYS_SYSTEM_FONT))
        legend.Show()
    
    def refresh(self):
        self.widget.SetAngle(self.settings.getint(self.settingsSection(), 
                             'piechartangle') / 180. * math.pi)
        self.refreshParts()
        self.widget.Refresh()
        
    def refreshParts(self):
        series = self.widget._series  # pylint: disable=W0212
        tasks = self.presentation()
        total = len(tasks)
        counts = tasks.nrOfTasksPerStatus()
        for part, status in zip(series, task.Task.possibleStatuses()):
            nrTasks = counts[status]
            percentage = round(100. * nrTasks / total) if total else 0
            part.SetLabel(status.countLabel % (nrTasks, percentage))
            part.SetValue(nrTasks)
            part.SetColour(self.getFgColor(status))
        # PietCtrl can't handle empty pie charts:    
        if total == 0:
            series[0].SetValue(1)
       
    def getFgColor(self, status):
        color = wx.Colour(*eval(self.settings.get('fgcolor', 
                                                  '%stasks' % status)))
        if status == task.status.active and color == wx.BLACK:
            color = wx.BLUE
        return color
        
    def refreshItems(self, *args, **kwargs):  # pylint: disable=W0613
        self.refresh()
    
    def select(self, *args):
        pass
    
    def updateSelection(self, *args, **kwargs):
        pass

    def isTreeViewer(self):
        return False

    def onPieChartAngleChanged(self, value):  # pylint: disable=W0613
        self.refresh()

