__init__.py

'''
Copyright (c) 2010-2016 Kivy Team and other contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
'''

'''
Most of the code if taken directly from a kivy module, I have only made some
changes.
'''

from kivy.clock import Clock
from kivy.properties import OptionProperty, ObjectProperty, NumericProperty, \
    ReferenceListProperty, BooleanProperty, ListProperty, AliasProperty, \
    StringProperty
from kivy.config import Config
from kivy.metrics import sp
from functools import partial
from kivy.animation import Animation

_scroll_timeout = _scroll_distance = 0
if Config:
    _scroll_timeout = Config.getint('widgets', 'scroll_timeout')
    _scroll_distance = Config.getint('widgets', 'scroll_distance')


class SwipeBehavior(object):
    '''Swipe behavior. When combined with a widget, swiping in the rectangle
    defined by :attr:`swipe_rectangle` will swipe the widget.
    In this case to left or to right.
    The example.py file demonstrates the use.
    '''

    move_to = ListProperty()
    '''To move widget.
    :attr:`remove_from_left` is a :class:`~kivy.properties.ListProperty`,
    defaults to [None,None].
    '''

    remove_from_left = BooleanProperty(True)
    '''Choice to remove the widget from the left or not.
    :attr:`remove_from_left` is a :class:`~kivy.properties.BooleanProperty`,
    defaults to True.
    '''

    remove_from_right = BooleanProperty(True)
    '''Choice to remove the widget from the right or not.
    :attr:`remove_from_right` is a :class:`~kivy.properties.BooleanProperty`,
    defaults to True.
    '''

    opacity_reduction_rate = NumericProperty(.005)
    '''Change the rate at which opacity reduces.
    :attr:`opacity_reduction_rate` is a :class:
    `~kivy.properties.NumericProperty`, defaults to (.005).
    '''

    animation_type = StringProperty('linear')
    '''For setting animation type.
    :attr:`animation_type` is a :class:`~kivy.properties.StringProperty`,
    defaults to linear.
    '''

    animation_duration = NumericProperty(.5)
    '''For setting animation duration.
    :attr:`animation_duration` is a :class:`~kivy.properties.NumericProperty`,
    defaults to (.5).
    '''

    right_percentage = NumericProperty(35)
    '''When to delete from right side.
    :attr:`right_percentage` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 35.
    '''

    left_percentage = NumericProperty(35)
    '''When to delete from left side.
    :attr:`left_percentage` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 35.
    '''

    swipe_distance = NumericProperty(_scroll_distance)
    '''Distance to move before swiping the :class:`swipeBehavior`, in pixels.
    As soon as the distance has been traveled, the :class:`swipeBehavior` will
    start to swipe, and no touch event will go to children.

    :attr:`swipe_distance` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 20 (pixels), according to the default value of scroll_distance
    in user configuration.
    '''

    swipe_timeout = NumericProperty(_scroll_timeout)
    '''Timeout allowed to trigger the :attr:`swipe_distance`, in milliseconds.
    If the user has not moved :attr:`swipe_distance` within the timeout,
    swiping will be disabled, and the touch event will go to the children.

    :attr:`swipe_timeout` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 55 (milliseconds), according to the default value of
    scroll_timeout in user configuration.
    '''

    swipe_rect_x = NumericProperty(0)
    '''X position of the axis aligned bounding rectangle where swiping
    is allowed. In window coordinates.

    :attr:`swipe_rect_x` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 0.
    '''

    swipe_rect_y = NumericProperty(0)
    '''Y position of the axis aligned bounding rectangle where swiping
    is allowed. In window coordinates.

    :attr:`swipe_rect_Y` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 0.
    '''

    swipe_rect_width = NumericProperty(100)
    '''Width of the axis aligned bounding rectangle where swiping is allowed.

    :attr:`swipe_rect_width` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 100.
    '''

    swipe_rect_height = NumericProperty(100)
    '''Height of the axis aligned bounding rectangle where swiping is allowed.

    :attr:`swipe_rect_height` is a :class:`~kivy.properties.NumericProperty`,
    defaults to 100.
    '''

    swipe_rectangle = ReferenceListProperty(swipe_rect_x, swipe_rect_y,
                                        swipe_rect_width, swipe_rect_height)
    '''Position and size of the axis aligned bounding rectangle where swiping
    is allowed.

    :attr:`swipe_rectangle` is a :class:`~kivy.properties.ReferenceListProperty`
    of (:attr:`swipe_rect_x`, :attr:`swipe_rect_y`, :attr:`swipe_rect_width`,
    :attr:`swipe_rect_height`) properties.
    '''

    def __init__(self, **kwargs):
        self._swipe_touch = None
        super(SwipeBehavior, self).__init__(**kwargs)

    def _get_uid(self, prefix='sv'):
        return '{0}.{1}'.format(prefix, self.uid)

    def animate_back(self):
        '''Take the widget back to its original position by using animation.
        '''
        if not self.move_to==[]:
            anim1 = Animation(x=self.move_to[0], y=self.move_to[1],
                              t=self.animation_type,
                              duration=self.animation_duration)
            anim1.start(self)
        else:
            pass

    def on_touch_down(self, touch):
        xx, yy, w, h = self.swipe_rectangle
        x, y = touch.pos

        if not self.collide_point(x, y):
            touch.ud[self._get_uid('svavoid')] = True
            return super(SwipeBehavior, self).on_touch_down(touch)
        if self._swipe_touch or ('button' in touch.profile and
                                touch.button.startswith('scroll')) or\
                not ((xx < x <= xx + w) and (yy < y <= yy + h)):
            return super(SwipeBehavior, self).on_touch_down(touch)

        # no mouse scrolling, so the user is going to swipe with this touch.
        self._swipe_touch = touch
        uid = self._get_uid()
        touch.grab(self)
        touch.ud[uid] = {
            'mode': 'unknown',
            'dx': 0,
            'dy': 0}
        Clock.schedule_once(self._change_touch_mode,
                            self.swipe_timeout / 1000.)
        return True

    def on_touch_move(self, touch):
        if self._get_uid('svavoid') in touch.ud or\
                self._swipe_touch is not touch:
            return super(SwipeBehavior, self).on_touch_move(touch) or\
                self._get_uid() in touch.ud
        if touch.grab_current is not self:
            return True

        uid = self._get_uid()
        ud = touch.ud[uid]
        mode = ud['mode']
        if mode == 'unknown':
            ud['dx'] += abs(touch.dx)
            if ud['dx'] > sp(self.swipe_distance):
                mode = 'drag'
            ud['mode'] = mode
        if mode == 'drag':
            self.x += touch.dx
        return True

    def on_touch_up(self, touch):
        if self._get_uid('svavoid') in touch.ud:
            return super(SwipeBehavior, self).on_touch_up(touch)
        if self._swipe_touch and self in [x() for x in touch.grab_list]:
            touch.ungrab(self)
            self._swipe_touch = None
            ud = touch.ud[self._get_uid()]
            if ud['mode'] == 'unknown':
                super(SwipeBehavior, self).on_touch_down(touch)
                Clock.schedule_once(partial(self._do_touch_up, touch), .1)
        else:
            if self._swipe_touch is not touch:
                super(SwipeBehavior, self).on_touch_up(touch)
        return self._get_uid() in touch.ud

    def _do_touch_up(self, touch, *largs):
        super(SwipeBehavior, self).on_touch_up(touch)
        # don't forget about grab event!
        for x in touch.grab_list[:]:
            touch.grab_list.remove(x)
            x = x()
            if not x:
                continue
            touch.grab_current = x
            super(SwipeBehavior, self).on_touch_up(touch)
        touch.grab_current = None

    def _change_touch_mode(self, *largs):
        if not self._swipe_touch:
            return
        uid = self._get_uid()
        touch = self._swipe_touch
        ud = touch.ud[uid]
        if ud['mode'] != 'unknown':
            return
        touch.ungrab(self)
        self._swipe_touch = None
        super(SwipeBehavior, self).on_touch_down(touch)
        return

    def check_for_left(self):
        '''
        Delete the widget when on_touch_up method is called and the widget is
        left_percentage from the left.
        '''
        if hasattr(self.parent, 'width'):
            if (((self.x+self.width) - self.parent.x) / self.width
                            ) * 100 <= self.left_percentage:
                if self.remove_from_left:
                    self.parent.remove_widget(self)
            else:
                self.get_widget_back()
                self.animate_back()
        else:
            pass

    def check_for_right(self):
        '''
        Delete the widget when on_touch_up method is called and the widget is
        right_percentage from the right.
        '''
        if hasattr(self.parent, 'width'):
            if ((self.parent.width - self.x) / self.width
                        ) * 100 <= self.right_percentage:
                if self.remove_from_right:
                    self.parent.remove_widget(self)
            else:
                self.get_widget_back()
                self.animate_back()
        else:
            pass
    '''
    get the opacity of widget back
    '''
    def reduce_opacity(self):
        self.opacity -= self.opacity_reduction_rate

    def get_widget_back(self):
        self.opacity = 1.0