# Copyright (C) 2013 Patrick Totzke # This file is released under the GNU GPL, version 3 or a later revision. import urwid from .tree import Tree, SimpleTree class NoSpaceError(Exception): """too little space for requested decoration""" class DecoratedTree(Tree): """ :class:`Tree` that wraps around another :class:`Tree` and allows to read original content as well as decorated versions thereof. """ def __init__(self, content): if not isinstance(content, Tree): # do we need this? content = SimpleTree(content) self._tree = content self.root = self._tree.root def get_decorated(self, pos): """ return widget that consists of the content of original tree at given position plus its decoration. """ return self.decorate(pos, self[pos]) def decorate(self, pos, widget, is_first=True): """ decorate `widget` according to a position `pos` in the original tree. setting `is_first` to False indicates that we are decorating a line that is *part* of the (multi-line) content at this position, but not the first part. This allows to omit incoming arrow heads for example. """ return widget # pass on everything else to the original tree. def parent_position(self, pos): return self._tree.parent_position(pos) def first_child_position(self, pos): return self._tree.first_child_position(pos) def last_child_position(self, pos): return self._tree.last_child_position(pos) def next_sibling_position(self, pos): return self._tree.next_sibling_position(pos) def prev_sibling_position(self, pos): return self._tree.prev_sibling_position(pos) def __getitem__(self, pos): return self._tree[pos] class CollapseMixin(object): """ Mixin for :class:`Tree` that allows to collapse subtrees. This works by overwriting :meth:`[first|last]_child_position `, forcing them to return `None` if the given position is considered collapsed. We use a (given) callable `is_collapsed` that accepts positions and returns a boolean to determine which node is considered collapsed. """ def __init__(self, is_collapsed=lambda pos: False, **kwargs): self._initially_collapsed = is_collapsed self._divergent_positions = [] def is_collapsed(self, pos): """checks if given position is currently collapsed""" collapsed = self._initially_collapsed(pos) if pos in self._divergent_positions: collapsed = not collapsed return collapsed # implement functionality by overwriting local position transformations # TODO: ATM this assumes we are in a wrapper: it uses self._tree. # This is not necessarily true, for example for subclasses of SimpleTree! # maybe define this whole class as a wrapper? def last_child_position(self, pos): if self.is_collapsed(pos): return None return self._tree.last_child_position(pos) def first_child_position(self, pos): if self.is_collapsed(pos): return None return self._tree.first_child_position(pos) def collapsible(self, pos): return not self._tree.is_leaf(pos) def set_position_collapsed(self, pos, is_collapsed): if self.collapsible(pos): if self._initially_collapsed(pos) == is_collapsed: if pos in self._divergent_positions: self._divergent_positions.remove(pos) else: if pos not in self._divergent_positions: self._divergent_positions.append(pos) def toggle_collapsed(self, pos): self.set_position_collapsed(pos, not self.is_collapsed(pos)) def collapse(self, pos): self.set_position_collapsed(pos, True) def collapse_all(self): self.set_collapsed_all(True) def expand_all(self): self.set_collapsed_all(False) def set_collapsed_all(self, is_collapsed): self._initially_collapsed = lambda x: is_collapsed self._divergent_positions = [] def expand(self, pos): self.set_position_collapsed(pos, False) class CollapseIconMixin(CollapseMixin): """ Mixin for :class:`Tree` that allows to collapse subtrees and use an indicator icon in line decorations. This Mixin adds the ability to construct collapse-icon for a position, indicating its collapse status to :class:`CollapseMixin`. """ def __init__(self, is_collapsed=lambda pos: False, icon_collapsed_char='+', icon_expanded_char='-', icon_collapsed_att=None, icon_expanded_att=None, icon_frame_left_char='[', icon_frame_right_char=']', icon_frame_att=None, icon_focussed_att=None, **kwargs): """TODO: docstrings""" CollapseMixin.__init__(self, is_collapsed, **kwargs) self._icon_collapsed_char = icon_collapsed_char self._icon_expanded_char = icon_expanded_char self._icon_collapsed_att = icon_collapsed_att self._icon_expanded_att = icon_expanded_att self._icon_frame_left_char = icon_frame_left_char self._icon_frame_right_char = icon_frame_right_char self._icon_frame_att = icon_frame_att self._icon_focussed_att = icon_focussed_att def _construct_collapse_icon(self, pos): width = 0 widget = None char = self._icon_expanded_char charatt = self._icon_expanded_att if self.is_collapsed(pos): char = self._icon_collapsed_char charatt = self._icon_collapsed_att if char is not None: columns = [] if self._icon_frame_left_char is not None: lchar = self._icon_frame_left_char charlen = len(lchar) leftframe = urwid.Text((self._icon_frame_att, lchar)) columns.append((charlen, leftframe)) width += charlen # next we build out icon widget: we feed all markups to a Text, # make it selectable (to toggle collapse) if requested markup = (charatt, char) widget = urwid.Text(markup) charlen = len(char) columns.append((charlen, widget)) width += charlen if self._icon_frame_right_char is not None: rchar = self._icon_frame_right_char charlen = len(rchar) rightframe = urwid.Text((self._icon_frame_att, rchar)) columns.append((charlen, rightframe)) width += charlen widget = urwid.Columns(columns) return width, widget class CollapsibleTree(CollapseMixin, DecoratedTree): """Undecorated Tree that allows to collapse subtrees""" def __init__(self, tree, **kwargs): DecoratedTree.__init__(self, tree) CollapseMixin.__init__(self, **kwargs) class IndentedTree(DecoratedTree): """Indent tree nodes according to their depth in the tree""" def __init__(self, tree, indent=2): """ :param tree: tree of widgets to be displayed :type tree: Tree :param indent: indentation width :type indent: int """ self._indent = indent DecoratedTree.__init__(self, tree) def decorate(self, pos, widget, is_first=True): indent = self._tree.depth(pos) * self._indent cols = [(indent, urwid.SolidFill(' ')), widget] # construct a Columns, defining all spacer as Box widgets line = urwid.Columns(cols, box_columns=range(len(cols))[:-1]) return line class CollapsibleIndentedTree(CollapseIconMixin, IndentedTree): """ Indent collapsible tree nodes according to their depth in the tree and display icons indicating collapse-status in the gaps. """ def __init__(self, walker, icon_offset=1, indent=4, **kwargs): """ :param walker: tree of widgets to be displayed :type walker: Tree :param indent: indentation width :type indent: int :param icon_offset: distance from icon to the eginning of the tree node. :type icon_offset: int """ self._icon_offset = icon_offset IndentedTree.__init__(self, walker, indent=indent) CollapseIconMixin.__init__(self, **kwargs) def decorate(self, pos, widget, is_first=True): """ builds a list element for given position in the tree. It consists of the original widget taken from the Tree and some decoration columns depending on the existence of parent and sibling positions. The result is a urwid.Columns widget. """ void = urwid.SolidFill(' ') line = None cols = [] depth = self._tree.depth(pos) # add spacer filling all but the last indent if depth > 0: cols.append((depth * self._indent, void)), # spacer # construct last indent # TODO iwidth, icon = self._construct_collapse_icon(pos) available_space = self._indent firstindent_width = self._icon_offset + iwidth # stop if indent is too small for this decoration if firstindent_width > available_space: raise NoSpaceError() # add icon only for non-leafs is_leaf = self._tree.is_leaf(pos) if not is_leaf: if icon is not None: # space to the left cols.append((available_space - firstindent_width, urwid.SolidFill(' '))) # icon icon_pile = urwid.Pile([('pack', icon), void]) cols.append((iwidth, icon_pile)) # spacer until original widget available_space = self._icon_offset cols.append((available_space, urwid.SolidFill(' '))) else: # otherwise just add another spacer cols.append((self._indent, urwid.SolidFill(' '))) cols.append(widget) # original widget ] # construct a Columns, defining all spacer as Box widgets line = urwid.Columns(cols, box_columns=range(len(cols))[:-1]) return line class ArrowTree(IndentedTree): """ Decorates the tree by indenting nodes according to their depth and using the gaps to draw arrows indicate the tree structure. """ def __init__(self, walker, indent=3, childbar_offset=0, arrow_hbar_char=u'\u2500', arrow_hbar_att=None, arrow_vbar_char=u'\u2502', arrow_vbar_att=None, arrow_tip_char=u'\u27a4', arrow_tip_att=None, arrow_att=None, arrow_connector_tchar=u'\u251c', arrow_connector_lchar=u'\u2514', arrow_connector_att=None, **kwargs): """ :param walker: tree of widgets to be displayed :type walker: Tree :param indent: indentation width :type indent: int """ IndentedTree.__init__(self, walker, indent) self._childbar_offset = childbar_offset self._arrow_hbar_char = arrow_hbar_char self._arrow_hbar_att = arrow_hbar_att self._arrow_vbar_char = arrow_vbar_char self._arrow_vbar_att = arrow_vbar_att self._arrow_connector_lchar = arrow_connector_lchar self._arrow_connector_tchar = arrow_connector_tchar self._arrow_connector_att = arrow_connector_att self._arrow_tip_char = arrow_tip_char self._arrow_tip_att = arrow_tip_att self._arrow_att = arrow_att def _construct_spacer(self, pos, acc): """ build a spacer that occupies the horizontally indented space between pos's parent and the root node. It will return a list of tuples to be fed into a Columns widget. """ parent = self._tree.parent_position(pos) if parent is not None: grandparent = self._tree.parent_position(parent) if self._indent > 0 and grandparent is not None: parent_sib = self._tree.next_sibling_position(parent) draw_vbar = parent_sib is not None and \ self._arrow_vbar_char is not None space_width = self._indent - 1 * (draw_vbar) - self._childbar_offset if space_width > 0: void = urwid.AttrMap(urwid.SolidFill(' '), self._arrow_att) acc.insert(0, ((space_width, void))) if draw_vbar: barw = urwid.SolidFill(self._arrow_vbar_char) bar = urwid.AttrMap(barw, self._arrow_vbar_att or self._arrow_att) acc.insert(0, ((1, bar))) return self._construct_spacer(parent, acc) else: return acc def _construct_connector(self, pos): """ build widget to be used as "connector" bit between the vertical bar between siblings and their respective horizontal bars leading to the arrow tip """ # connector symbol, either L or |- shaped. connectorw = None connector = None if self._tree.next_sibling_position(pos) is not None: # |- shaped if self._arrow_connector_tchar is not None: connectorw = urwid.Text(self._arrow_connector_tchar) else: # L shaped if self._arrow_connector_lchar is not None: connectorw = urwid.Text(self._arrow_connector_lchar) if connectorw is not None: att = self._arrow_connector_att or self._arrow_att connector = urwid.AttrMap(connectorw, att) return connector def _construct_arrow_tip(self, pos): """returns arrow tip as (width, widget)""" arrow_tip = None width = 0 if self._arrow_tip_char: txt = urwid.Text(self._arrow_tip_char) arrow_tip = urwid.AttrMap( txt, self._arrow_tip_att or self._arrow_att) width = len(self._arrow_tip_char) return width, arrow_tip def _construct_first_indent(self, pos): """ build spacer to occupy the first indentation level from pos to the left. This is separate as it adds arrowtip and sibling connector. """ cols = [] void = urwid.AttrMap(urwid.SolidFill(' '), self._arrow_att) available_width = self._indent if self._tree.depth(pos) > 0: connector = self._construct_connector(pos) if connector is not None: width = connector.pack()[0] if width > available_width: raise NoSpaceError() available_width -= width if self._tree.next_sibling_position(pos) is not None: barw = urwid.SolidFill(self._arrow_vbar_char) below = urwid.AttrMap(barw, self._arrow_vbar_att or self._arrow_att) else: below = void # pile up connector and bar spacer = urwid.Pile([('pack', connector), below]) cols.append((width, spacer)) #arrow tip awidth, at = self._construct_arrow_tip(pos) if at is not None: if awidth > available_width: raise NoSpaceError() available_width -= awidth at_spacer = urwid.Pile([('pack', at), void]) cols.append((awidth, at_spacer)) # bar between connector and arrow tip if available_width > 0: barw = urwid.SolidFill(self._arrow_hbar_char) bar = urwid.AttrMap( barw, self._arrow_hbar_att or self._arrow_att) hb_spacer = urwid.Pile([(1, bar), void]) cols.insert(1, (available_width, hb_spacer)) return cols def decorate(self, pos, widget, is_first=True): """ builds a list element for given position in the tree. It consists of the original widget taken from the Tree and some decoration columns depending on the existence of parent and sibling positions. The result is a urwid.Columns widget. """ line = None if pos is not None: original_widget = widget cols = self._construct_spacer(pos, []) # Construct arrow leading from parent here, # if we have a parent and indentation is turned on if self._indent > 0: if is_first: indent = self._construct_first_indent(pos) if indent is not None: cols = cols + indent else: parent = self._tree.parent_position(pos) if self._indent > 0 and parent is not None: parent_sib = self._tree.next_sibling_position(pos) draw_vbar = parent_sib is not None void = urwid.AttrMap(urwid.SolidFill(' '), self._arrow_att) if self._childbar_offset > 0: cols.append((self._childbar_offset, void)) if draw_vbar: barw = urwid.SolidFill(self._arrow_vbar_char) bar = urwid.AttrMap( barw, self._arrow_vbar_att or self._arrow_att) rspace_width = self._indent - \ 1 - self._childbar_offset cols.append((1, bar)) cols.append((rspace_width, void)) else: cols.append((self._indent, void)) # add the original widget for this line cols.append(original_widget) # construct a Columns, defining all spacer as Box widgets line = urwid.Columns(cols, box_columns=range(len(cols))[:-1]) return line class CollapsibleArrowTree(CollapseIconMixin, ArrowTree): """Arrow-decoration that allows collapsing subtrees""" def __init__(self, treelistwalker, icon_offset=0, indent=5, **kwargs): self._icon_offset = icon_offset ArrowTree.__init__(self, treelistwalker, indent, **kwargs) CollapseIconMixin.__init__(self, **kwargs) def _construct_arrow_tip(self, pos): cols = [] overall_width = self._icon_offset if self._icon_offset > 0: # how often we repeat the hbar_char until width icon_offset is # reached hbar_char_count = len(self._arrow_hbar_char) / self._icon_offset barw = urwid.Text(self._arrow_hbar_char * hbar_char_count) bar = urwid.AttrMap(barw, self._arrow_hbar_att or self._arrow_att) cols.insert(1, (self._icon_offset, bar)) # add icon only for non-leafs if self.collapsible(pos): iwidth, icon = self._construct_collapse_icon(pos) if icon is not None: cols.insert(0, (iwidth, icon)) overall_width += iwidth # get arrow tip awidth, tip = ArrowTree._construct_arrow_tip(self, pos) if tip is not None: cols.append((awidth, tip)) overall_width += awidth return overall_width, urwid.Columns(cols)