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gramps/gramps/gen/lib/styledtext.py
2017-02-17 21:45:46 +00:00

385 lines
12 KiB
Python

#
# Gramps - a GTK+/GNOME based genealogy program
#
# Copyright (C) 2008 Zsolt Foldvari
# Copyright (C) 2013 Doug Blank <doug.blank@gmail.com>
# Copyright (C) 2017 Nick Hall
#
# This program 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 2 of the License, or
# (at your option) any later version.
#
# This program 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
#
"Handling formatted ('rich text') strings"
#-------------------------------------------------------------------------
#
# Gramps modules
#
#-------------------------------------------------------------------------
from .styledtexttag import StyledTextTag
#-------------------------------------------------------------------------
#
# StyledText class
#
#-------------------------------------------------------------------------
class StyledText:
"""Helper class to enable character based text formatting.
:py:class:`StyledText` is a wrapper class binding the clear text string and
it's formatting tags together.
:py:class:`StyledText` provides several string methods in order to
manipulate formatted strings, such as :py:meth:`join`, :py:meth:`replace`,
:py:meth:`split`, and also supports the '+' operation (:py:meth:`__add__`).
To get the clear text of the :py:class:`StyledText` use the built-in
:py:func:`str()` function. To get the list of formatting tags use the
:py:meth:`get_tags` method.
StyledText supports the *creation* of formatted texts too. This feature
is intended to replace (or extend) the current report interface.
To be continued... FIXME
:ivar string: (str) The clear text part.
:ivar tags: (list of :py:class:`.StyledTextTag`) Text tags holding
formatting information for the string.
:cvar POS_TEXT: Position of *string* attribute in the serialized format of
an instance.
:cvar POS_TAGS: (int) Position of *tags* attribute in the serialized format
of an instance.
.. warning:: The POS_<x> class variables reflect the serialized object,
they have to be updated in case the data structure or the
:py:meth:`serialize` method changes!
.. note::
1. There is no sanity check of tags in :py:meth:`__init__`, because when a
:py:class:`StyledText` is displayed it is passed to a
:py:class:`.StyledTextBuffer`, which in turn will 'eat' all invalid
tags (including out-of-range tags too).
2. After string methods the tags can become fragmented. That means the same
tag may appear more than once in the tag list with different ranges.
There could be a 'merge_tags' functionality in :py:meth:`__init__`,
however :py:class:`StyledTextBuffer` will merge them automatically if
the text is displayed.
"""
(POS_TEXT, POS_TAGS) = list(range(2))
def __init__(self, text="", tags=None):
"""Setup initial instance variable values."""
self._string = text
if tags:
self._tags = tags
else:
self._tags = []
# special methods
def __str__(self):
return self._string.__str__()
def __repr__(self):
return self._string.__repr__()
def __add__(self, other):
"""Implement '+' operation on the class.
:param other: string to concatenate to self
:type other: basestring or :py:class:`StyledText`
:return: concatenated strings
:rtype: :py:class:`StyledText`
"""
offset = len(self._string)
if isinstance(other, StyledText):
# need to join strings and merge tags
for tag in other.tags:
tag.ranges = [(start + offset, end + offset)
for (start, end) in tag.ranges]
return self.__class__("".join([self._string, other.string]),
self._tags + other.tags)
elif isinstance(other, str):
# tags remain the same, only text becomes longer
return self.__class__("".join([self._string, other]), self._tags)
else:
return self.__class__("".join([self._string, str(other)]),
self._tags)
def __eq__(self, other):
return self._string == other.string and self._tags == other.tags
def __ne__(self, other):
return self._string != other.string or self._tags != other.tags
def __lt__(self, other):
return self._string < other.string
def __le__(self, other):
return self.__lt__(other) or self.__eq__(other)
def __gt__(self, other):
return not self.__le__(other)
def __ge__(self, other):
return self.__gt__(other) or self.__eq__(other)
def __mod__(self, other):
"""Implement '%' operation on the class."""
# This will raise an exception if the formatting operation is invalid
self._string % other
result = self.__class__(self._string, self._tags)
start = 0
while True:
idx1 = result.string.find('%', start)
if idx1 < 0:
break
if result.string[idx1+1] == '(':
idx2 = result.string.find(')', idx1+3)
param_name = result.string[idx1+2:idx2]
else:
idx2 = idx1
param_name = None
end = idx2 + 1
for end in range(idx2+1, len(result.string)):
if result.string[end] in 'diouxXeEfFgGcrs%':
break
if param_name is not None:
param = other[param_name]
elif isinstance(other, tuple):
param = other[0]
other = other[1:]
else:
param = other
if not isinstance(param, StyledText):
param_type = '%' + result.string[idx2+1:end+1]
param = StyledText(param_type % param)
parts = result.split(result.string[idx1:end+1], 1)
if len(parts) == 2:
result = parts[0] + param + parts[1]
start = end + 1
return result
# private methods
# string methods in alphabetical order:
def join(self, seq):
"""
Emulate :py:meth:`__builtin__.str.join` method.
:param seq: list of strings to join
:type seq: basestring or :py:class:`StyledText`
:return: joined strings
:rtype: :py:class:`StyledText`
"""
new_string = self._string.join([str(string) for string in seq])
offset = 0
new_tags = []
self_len = len(self._string)
for text in seq:
if isinstance(text, StyledText):
for tag in text.tags:
tag.ranges = [(start + offset, end + offset)
for (start, end) in tag.ranges]
new_tags += [tag]
offset = offset + len(str(text)) + self_len
return self.__class__(new_string, new_tags)
def replace(self, old, new, count=-1):
"""
Emulate :py:meth:`__builtin__.str.replace` method.
:param old: substring to be replaced
:type old: basestring or :py:class:`StyledText`
:param new: substring to replace by
:type new: :py:class:`StyledText`
:param count: if given, only the first count occurrences are replaced
:type count: int
:return: copy of the string with replaced substring(s)
:rtype: :py:class:`StyledText`
.. warning:: by the correct implementation parameter *new* should be
:py:class:`StyledText` or basestring, however only
:py:class:`StyledText` is currently supported.
"""
# quick and dirty solution: works only if new.__class__ == StyledText
return new.join(self.split(old, count))
def split(self, sep=None, maxsplit=-1):
"""
Emulate :py:meth:`__builtin__.str.split` method.
:param sep: the delimiter string
:type seq: basestring or :py:class:`StyledText`
:param maxsplit: if given, at most maxsplit splits are done
:type maxsplit: int
:return: a list of the words in the string
:rtype: list of :py:class:`StyledText`
"""
# split the clear text first
if sep is not None:
sep = str(sep)
string_list = self._string.split(sep, maxsplit)
# then split the tags too
end_string = 0
styledtext_list = []
for string in string_list:
start_string = self._string.find(string, end_string)
end_string = start_string + len(string)
new_tags = []
for tag in self._tags:
new_tag = StyledTextTag(int(tag.name), tag.value)
for (start_tag, end_tag) in tag.ranges:
start = max(start_string, start_tag)
end = min(end_string, end_tag)
if start < end:
new_tag.ranges.append((start - start_string,
end - start_string))
if new_tag.ranges:
new_tags.append(new_tag)
styledtext_list.append(self.__class__(string, new_tags))
return styledtext_list
# other public methods
def serialize(self):
"""
Convert the object to a serialized tuple of data.
:return: Serialized format of the instance.
:rtype: tuple
"""
if self._tags:
the_tags = [tag.serialize() for tag in self._tags]
else:
the_tags = []
return (self._string, the_tags)
@classmethod
def get_schema(cls):
"""
Returns the JSON Schema for this class.
:returns: Returns a dict containing the schema.
:rtype: dict
"""
return {
"type": "object",
"properties": {
"_class": {"enum": [cls.__name__]},
"string": {"type": "string"},
"tags": {"type": "array",
"items": StyledTextTag.get_schema()}
}
}
@classmethod
def get_labels(cls, _):
return {
"string": _("Text"),
"tags": _("Styled Text Tags"),
}
def unserialize(self, data):
"""
Convert a serialized tuple of data to an object.
:param data: Serialized format of instance variables.
:type data: tuple
"""
(self._string, the_tags) = data
# I really wonder why this doesn't work... it does for all other types
#self._tags = [StyledTextTag().unserialize(tag) for tag in the_tags]
for tag in the_tags:
stt = StyledTextTag()
stt.unserialize(tag)
self._tags.append(stt)
return self
def get_tags(self):
"""
Return the list of formatting tags.
:return: The formatting tags applied on the text.
:rtype: list of 0 or more :py:class:`.StyledTextTag` instances.
"""
return self._tags
def set_tags(self, tags):
"""
Set the list of formatting tags.
:param tags: The formatting tags applied on the text.
:type tags: list of 0 or more :py:class:`.StyledTextTag` instances.
"""
self._tags = tags
def get_string(self):
"""
Accessor for the associated string.
"""
return self._string
def set_string(self, string):
"""
Setter for the associated string.
"""
self._string = string
tags = property(get_tags, set_tags)
string = property(get_string, set_string)
if __name__ == '__main__':
from .styledtexttagtype import StyledTextTagType
T1 = StyledTextTag(StyledTextTagType(1), 'v1', [(0, 2), (2, 4), (4, 6)])
T2 = StyledTextTag(StyledTextTagType(2), 'v2', [(1, 3), (3, 5), (0, 7)])
A = StyledText('123X456', [T1])
B = StyledText("abcXdef", [T2])
C = StyledText('\n')
S = 'cleartext'
C = C.join([A, S, B])
L = C.split()
C = C.replace('X', StyledText('_'))
A = A + B
print(A)