/cmpt470/group8wiki/skins/vector/cssjanus/cssjanus.py
Python | 574 lines | 568 code | 1 blank | 5 comment | 0 complexity | c6ef0739f990b054959206797b29ffa1 MD5 | raw file
- #!/usr/bin/python
- #
- # Copyright 2008 Google Inc. All Rights Reserved.
- """Converts a LeftToRight Cascading Style Sheet into a RightToLeft one.
- This is a utility script for replacing "left" oriented things in a CSS file
- like float, padding, margin with "right" oriented values.
- It also does the opposite.
- The goal is to be able to conditionally serve one large, cat'd, compiled CSS
- file appropriate for LeftToRight oriented languages and RightToLeft ones.
- This utility will hopefully help your structural layout done in CSS in
- terms of its RTL compatibility. It will not help with some of the more
- complicated bidirectional text issues.
- """
- __author__ = 'elsigh@google.com (Lindsey Simon)'
- __version__ = '0.1'
- import logging
- import re
- import sys
- import getopt
- import os
- import csslex
- logging.getLogger().setLevel(logging.INFO)
- # Global for the command line flags.
- SWAP_LTR_RTL_IN_URL_DEFAULT = False
- SWAP_LEFT_RIGHT_IN_URL_DEFAULT = False
- FLAGS = {'swap_ltr_rtl_in_url': SWAP_LTR_RTL_IN_URL_DEFAULT,
- 'swap_left_right_in_url': SWAP_LEFT_RIGHT_IN_URL_DEFAULT}
- # Generic token delimiter character.
- TOKEN_DELIMITER = '~'
- # This is a temporary match token we use when swapping strings.
- TMP_TOKEN = '%sTMP%s' % (TOKEN_DELIMITER, TOKEN_DELIMITER)
- # Token to be used for joining lines.
- TOKEN_LINES = '%sJ%s' % (TOKEN_DELIMITER, TOKEN_DELIMITER)
- # Global constant text strings for CSS value matches.
- LTR = 'ltr'
- RTL = 'rtl'
- LEFT = 'left'
- RIGHT = 'right'
- # This is a lookbehind match to ensure that we don't replace instances
- # of our string token (left, rtl, etc...) if there's a letter in front of it.
- # Specifically, this prevents replacements like 'background: url(bright.png)'.
- LOOKBEHIND_NOT_LETTER = r'(?<![a-zA-Z])'
- # This is a lookahead match to make sure we don't replace left and right
- # in actual classnames, so that we don't break the HTML/CSS dependencies.
- # Read literally, it says ignore cases where the word left, for instance, is
- # directly followed by valid classname characters and a curly brace.
- # ex: .column-left {float: left} will become .column-left {float: right}
- LOOKAHEAD_NOT_OPEN_BRACE = (r'(?!(?:%s|%s|%s|#|\:|\.|\,|\+|>)*?{)' %
- (csslex.NMCHAR, TOKEN_LINES, csslex.SPACE))
- # These two lookaheads are to test whether or not we are within a
- # background: url(HERE) situation.
- # Ref: http://www.w3.org/TR/CSS21/syndata.html#uri
- VALID_AFTER_URI_CHARS = r'[\'\"]?%s' % csslex.WHITESPACE
- LOOKAHEAD_NOT_CLOSING_PAREN = r'(?!%s?%s\))' % (csslex.URL_CHARS,
- VALID_AFTER_URI_CHARS)
- LOOKAHEAD_FOR_CLOSING_PAREN = r'(?=%s?%s\))' % (csslex.URL_CHARS,
- VALID_AFTER_URI_CHARS)
- # Compile a regex to swap left and right values in 4 part notations.
- # We need to match negatives and decimal numeric values.
- # ex. 'margin: .25em -2px 3px 0' becomes 'margin: .25em 0 3px -2px'.
- POSSIBLY_NEGATIVE_QUANTITY = r'((?:-?%s)|(?:inherit|auto))' % csslex.QUANTITY
- POSSIBLY_NEGATIVE_QUANTITY_SPACE = r'%s%s%s' % (POSSIBLY_NEGATIVE_QUANTITY,
- csslex.SPACE,
- csslex.WHITESPACE)
- FOUR_NOTATION_QUANTITY_RE = re.compile(r'%s%s%s%s' %
- (POSSIBLY_NEGATIVE_QUANTITY_SPACE,
- POSSIBLY_NEGATIVE_QUANTITY_SPACE,
- POSSIBLY_NEGATIVE_QUANTITY_SPACE,
- POSSIBLY_NEGATIVE_QUANTITY),
- re.I)
- COLOR = r'(%s|%s)' % (csslex.NAME, csslex.HASH)
- COLOR_SPACE = r'%s%s' % (COLOR, csslex.SPACE)
- FOUR_NOTATION_COLOR_RE = re.compile(r'(-color%s:%s)%s%s%s(%s)' %
- (csslex.WHITESPACE,
- csslex.WHITESPACE,
- COLOR_SPACE,
- COLOR_SPACE,
- COLOR_SPACE,
- COLOR),
- re.I)
- # Compile the cursor resize regexes
- CURSOR_EAST_RE = re.compile(LOOKBEHIND_NOT_LETTER + '([ns]?)e-resize')
- CURSOR_WEST_RE = re.compile(LOOKBEHIND_NOT_LETTER + '([ns]?)w-resize')
- # Matches the condition where we need to replace the horizontal component
- # of a background-position value when expressed in horizontal percentage.
- # Had to make two regexes because in the case of position-x there is only
- # one quantity, and otherwise we don't want to match and change cases with only
- # one quantity.
- BG_HORIZONTAL_PERCENTAGE_RE = re.compile(r'background(-position)?(%s:%s)'
- '([^%%]*?)(%s)%%'
- '(%s(?:%s|%s))' % (csslex.WHITESPACE,
- csslex.WHITESPACE,
- csslex.NUM,
- csslex.WHITESPACE,
- csslex.QUANTITY,
- csslex.IDENT))
- BG_HORIZONTAL_PERCENTAGE_X_RE = re.compile(r'background-position-x(%s:%s)'
- '(%s)%%' % (csslex.WHITESPACE,
- csslex.WHITESPACE,
- csslex.NUM))
- # Matches the opening of a body selector.
- BODY_SELECTOR = r'body%s{%s' % (csslex.WHITESPACE, csslex.WHITESPACE)
- # Matches anything up until the closing of a selector.
- CHARS_WITHIN_SELECTOR = r'[^\}]*?'
- # Matches the direction property in a selector.
- DIRECTION_RE = r'direction%s:%s' % (csslex.WHITESPACE, csslex.WHITESPACE)
- # These allow us to swap "ltr" with "rtl" and vice versa ONLY within the
- # body selector and on the same line.
- BODY_DIRECTION_LTR_RE = re.compile(r'(%s)(%s)(%s)(ltr)' %
- (BODY_SELECTOR, CHARS_WITHIN_SELECTOR,
- DIRECTION_RE),
- re.I)
- BODY_DIRECTION_RTL_RE = re.compile(r'(%s)(%s)(%s)(rtl)' %
- (BODY_SELECTOR, CHARS_WITHIN_SELECTOR,
- DIRECTION_RE),
- re.I)
- # Allows us to swap "direction:ltr" with "direction:rtl" and
- # vice versa anywhere in a line.
- DIRECTION_LTR_RE = re.compile(r'%s(ltr)' % DIRECTION_RE)
- DIRECTION_RTL_RE = re.compile(r'%s(rtl)' % DIRECTION_RE)
- # We want to be able to switch left with right and vice versa anywhere
- # we encounter left/right strings, EXCEPT inside the background:url(). The next
- # two regexes are for that purpose. We have alternate IN_URL versions of the
- # regexes compiled in case the user passes the flag that they do
- # actually want to have left and right swapped inside of background:urls.
- LEFT_RE = re.compile('%s(%s)%s%s' % (LOOKBEHIND_NOT_LETTER,
- LEFT,
- LOOKAHEAD_NOT_CLOSING_PAREN,
- LOOKAHEAD_NOT_OPEN_BRACE),
- re.I)
- RIGHT_RE = re.compile('%s(%s)%s%s' % (LOOKBEHIND_NOT_LETTER,
- RIGHT,
- LOOKAHEAD_NOT_CLOSING_PAREN,
- LOOKAHEAD_NOT_OPEN_BRACE),
- re.I)
- LEFT_IN_URL_RE = re.compile('%s(%s)%s' % (LOOKBEHIND_NOT_LETTER,
- LEFT,
- LOOKAHEAD_FOR_CLOSING_PAREN),
- re.I)
- RIGHT_IN_URL_RE = re.compile('%s(%s)%s' % (LOOKBEHIND_NOT_LETTER,
- RIGHT,
- LOOKAHEAD_FOR_CLOSING_PAREN),
- re.I)
- LTR_IN_URL_RE = re.compile('%s(%s)%s' % (LOOKBEHIND_NOT_LETTER,
- LTR,
- LOOKAHEAD_FOR_CLOSING_PAREN),
- re.I)
- RTL_IN_URL_RE = re.compile('%s(%s)%s' % (LOOKBEHIND_NOT_LETTER,
- RTL,
- LOOKAHEAD_FOR_CLOSING_PAREN),
- re.I)
- COMMENT_RE = re.compile('(%s)' % csslex.COMMENT, re.I)
- NOFLIP_TOKEN = r'\@noflip'
- # The NOFLIP_TOKEN inside of a comment. For now, this requires that comments
- # be in the input, which means users of a css compiler would have to run
- # this script first if they want this functionality.
- NOFLIP_ANNOTATION = r'/\*%s%s%s\*/' % (csslex.WHITESPACE,
- NOFLIP_TOKEN,
- csslex. WHITESPACE)
- # After a NOFLIP_ANNOTATION, and within a class selector, we want to be able
- # to set aside a single rule not to be flipped. We can do this by matching
- # our NOFLIP annotation and then using a lookahead to make sure there is not
- # an opening brace before the match.
- NOFLIP_SINGLE_RE = re.compile(r'(%s%s[^;}]+;?)' % (NOFLIP_ANNOTATION,
- LOOKAHEAD_NOT_OPEN_BRACE),
- re.I)
- # After a NOFLIP_ANNOTATION, we want to grab anything up until the next } which
- # means the entire following class block. This will prevent all of its
- # declarations from being flipped.
- NOFLIP_CLASS_RE = re.compile(r'(%s%s})' % (NOFLIP_ANNOTATION,
- CHARS_WITHIN_SELECTOR),
- re.I)
- class Tokenizer:
- """Replaces any CSS comments with string tokens and vice versa."""
- def __init__(self, token_re, token_string):
- """Constructor for the Tokenizer.
- Args:
- token_re: A regex for the string to be replace by a token.
- token_string: The string to put between token delimiters when tokenizing.
- """
- logging.debug('Tokenizer::init token_string=%s' % token_string)
- self.token_re = token_re
- self.token_string = token_string
- self.originals = []
- def Tokenize(self, line):
- """Replaces any string matching token_re in line with string tokens.
- By passing a function as an argument to the re.sub line below, we bypass
- the usual rule where re.sub will only replace the left-most occurrence of
- a match by calling the passed in function for each occurrence.
- Args:
- line: A line to replace token_re matches in.
- Returns:
- line: A line with token_re matches tokenized.
- """
- line = self.token_re.sub(self.TokenizeMatches, line)
- logging.debug('Tokenizer::Tokenize returns: %s' % line)
- return line
- def DeTokenize(self, line):
- """Replaces tokens with the original string.
- Args:
- line: A line with tokens.
- Returns:
- line with any tokens replaced by the original string.
- """
- # Put all of the comments back in by their comment token.
- for i, original in enumerate(self.originals):
- token = '%s%s_%s%s' % (TOKEN_DELIMITER, self.token_string, i + 1,
- TOKEN_DELIMITER)
- line = line.replace(token, original)
- logging.debug('Tokenizer::DeTokenize i:%s w/%s' % (i, token))
- logging.debug('Tokenizer::DeTokenize returns: %s' % line)
- return line
- def TokenizeMatches(self, m):
- """Replaces matches with tokens and stores the originals.
- Args:
- m: A match object.
- Returns:
- A string token which replaces the CSS comment.
- """
- logging.debug('Tokenizer::TokenizeMatches %s' % m.group(1))
- self.originals.append(m.group(1))
- return '%s%s_%s%s' % (TOKEN_DELIMITER,
- self.token_string,
- len(self.originals),
- TOKEN_DELIMITER)
- def FixBodyDirectionLtrAndRtl(line):
- """Replaces ltr with rtl and vice versa ONLY in the body direction.
- Args:
- line: A string to replace instances of ltr with rtl.
- Returns:
- line with direction: ltr and direction: rtl swapped only in body selector.
- line = FixBodyDirectionLtrAndRtl('body { direction:ltr }')
- line will now be 'body { direction:rtl }'.
- """
- line = BODY_DIRECTION_LTR_RE.sub('\\1\\2\\3%s' % TMP_TOKEN, line)
- line = BODY_DIRECTION_RTL_RE.sub('\\1\\2\\3%s' % LTR, line)
- line = line.replace(TMP_TOKEN, RTL)
- logging.debug('FixBodyDirectionLtrAndRtl returns: %s' % line)
- return line
- def FixLeftAndRight(line):
- """Replaces left with right and vice versa in line.
- Args:
- line: A string in which to perform the replacement.
- Returns:
- line with left and right swapped. For example:
- line = FixLeftAndRight('padding-left: 2px; margin-right: 1px;')
- line will now be 'padding-right: 2px; margin-left: 1px;'.
- """
- line = LEFT_RE.sub(TMP_TOKEN, line)
- line = RIGHT_RE.sub(LEFT, line)
- line = line.replace(TMP_TOKEN, RIGHT)
- logging.debug('FixLeftAndRight returns: %s' % line)
- return line
- def FixLeftAndRightInUrl(line):
- """Replaces left with right and vice versa ONLY within background urls.
- Args:
- line: A string in which to replace left with right and vice versa.
- Returns:
- line with left and right swapped in the url string. For example:
- line = FixLeftAndRightInUrl('background:url(right.png)')
- line will now be 'background:url(left.png)'.
- """
- line = LEFT_IN_URL_RE.sub(TMP_TOKEN, line)
- line = RIGHT_IN_URL_RE.sub(LEFT, line)
- line = line.replace(TMP_TOKEN, RIGHT)
- logging.debug('FixLeftAndRightInUrl returns: %s' % line)
- return line
- def FixLtrAndRtlInUrl(line):
- """Replaces ltr with rtl and vice versa ONLY within background urls.
- Args:
- line: A string in which to replace ltr with rtl and vice versa.
- Returns:
- line with left and right swapped. For example:
- line = FixLtrAndRtlInUrl('background:url(rtl.png)')
- line will now be 'background:url(ltr.png)'.
- """
- line = LTR_IN_URL_RE.sub(TMP_TOKEN, line)
- line = RTL_IN_URL_RE.sub(LTR, line)
- line = line.replace(TMP_TOKEN, RTL)
- logging.debug('FixLtrAndRtlInUrl returns: %s' % line)
- return line
- def FixCursorProperties(line):
- """Fixes directional CSS cursor properties.
- Args:
- line: A string to fix CSS cursor properties in.
- Returns:
- line reformatted with the cursor properties substituted. For example:
- line = FixCursorProperties('cursor: ne-resize')
- line will now be 'cursor: nw-resize'.
- """
- line = CURSOR_EAST_RE.sub('\\1' + TMP_TOKEN, line)
- line = CURSOR_WEST_RE.sub('\\1e-resize', line)
- line = line.replace(TMP_TOKEN, 'w-resize')
- logging.debug('FixCursorProperties returns: %s' % line)
- return line
- def FixFourPartNotation(line):
- """Fixes the second and fourth positions in 4 part CSS notation.
- Args:
- line: A string to fix 4 part CSS notation in.
- Returns:
- line reformatted with the 4 part notations swapped. For example:
- line = FixFourPartNotation('padding: 1px 2px 3px 4px')
- line will now be 'padding: 1px 4px 3px 2px'.
- """
- line = FOUR_NOTATION_QUANTITY_RE.sub('\\1 \\4 \\3 \\2', line)
- line = FOUR_NOTATION_COLOR_RE.sub('\\1\\2 \\5 \\4 \\3', line)
- logging.debug('FixFourPartNotation returns: %s' % line)
- return line
- def FixBackgroundPosition(line):
- """Fixes horizontal background percentage values in line.
- Args:
- line: A string to fix horizontal background position values in.
- Returns:
- line reformatted with the 4 part notations swapped.
- """
- line = BG_HORIZONTAL_PERCENTAGE_RE.sub(CalculateNewBackgroundPosition, line)
- line = BG_HORIZONTAL_PERCENTAGE_X_RE.sub(CalculateNewBackgroundPositionX,
- line)
- logging.debug('FixBackgroundPosition returns: %s' % line)
- return line
- def CalculateNewBackgroundPosition(m):
- """Fixes horizontal background-position percentages.
- This function should be used as an argument to re.sub since it needs to
- perform replacement specific calculations.
- Args:
- m: A match object.
- Returns:
- A string with the horizontal background position percentage fixed.
- BG_HORIZONTAL_PERCENTAGE_RE.sub(FixBackgroundPosition,
- 'background-position: 75% 50%')
- will return 'background-position: 25% 50%'.
- """
- # The flipped value is the offset from 100%
- new_x = str(100-int(m.group(4)))
- # Since m.group(1) may very well be None type and we need a string..
- if m.group(1):
- position_string = m.group(1)
- else:
- position_string = ''
- return 'background%s%s%s%s%%%s' % (position_string, m.group(2), m.group(3),
- new_x, m.group(5))
- def CalculateNewBackgroundPositionX(m):
- """Fixes percent based background-position-x.
- This function should be used as an argument to re.sub since it needs to
- perform replacement specific calculations.
- Args:
- m: A match object.
- Returns:
- A string with the background-position-x percentage fixed.
- BG_HORIZONTAL_PERCENTAGE_X_RE.sub(CalculateNewBackgroundPosition,
- 'background-position-x: 75%')
- will return 'background-position-x: 25%'.
- """
- # The flipped value is the offset from 100%
- new_x = str(100-int(m.group(2)))
- return 'background-position-x%s%s%%' % (m.group(1), new_x)
- def ChangeLeftToRightToLeft(lines,
- swap_ltr_rtl_in_url=None,
- swap_left_right_in_url=None):
- """Turns lines into a stream and runs the fixing functions against it.
- Args:
- lines: An list of CSS lines.
- swap_ltr_rtl_in_url: Overrides this flag if param is set.
- swap_left_right_in_url: Overrides this flag if param is set.
- Returns:
- The same lines, but with left and right fixes.
- """
- global FLAGS
- # Possibly override flags with params.
- logging.debug('ChangeLeftToRightToLeft swap_ltr_rtl_in_url=%s, '
- 'swap_left_right_in_url=%s' % (swap_ltr_rtl_in_url,
- swap_left_right_in_url))
- if swap_ltr_rtl_in_url is None:
- swap_ltr_rtl_in_url = FLAGS['swap_ltr_rtl_in_url']
- if swap_left_right_in_url is None:
- swap_left_right_in_url = FLAGS['swap_left_right_in_url']
- # Turns the array of lines into a single line stream.
- logging.debug('LINES COUNT: %s' % len(lines))
- line = TOKEN_LINES.join(lines)
- # Tokenize any single line rules with the /* noflip */ annotation.
- noflip_single_tokenizer = Tokenizer(NOFLIP_SINGLE_RE, 'NOFLIP_SINGLE')
- line = noflip_single_tokenizer.Tokenize(line)
- # Tokenize any class rules with the /* noflip */ annotation.
- noflip_class_tokenizer = Tokenizer(NOFLIP_CLASS_RE, 'NOFLIP_CLASS')
- line = noflip_class_tokenizer.Tokenize(line)
- # Tokenize the comments so we can preserve them through the changes.
- comment_tokenizer = Tokenizer(COMMENT_RE, 'C')
- line = comment_tokenizer.Tokenize(line)
- # Here starteth the various left/right orientation fixes.
- line = FixBodyDirectionLtrAndRtl(line)
- if swap_left_right_in_url:
- line = FixLeftAndRightInUrl(line)
- if swap_ltr_rtl_in_url:
- line = FixLtrAndRtlInUrl(line)
- line = FixLeftAndRight(line)
- line = FixCursorProperties(line)
- line = FixFourPartNotation(line)
- line = FixBackgroundPosition(line)
- # DeTokenize the single line noflips.
- line = noflip_single_tokenizer.DeTokenize(line)
- # DeTokenize the class-level noflips.
- line = noflip_class_tokenizer.DeTokenize(line)
- # DeTokenize the comments.
- line = comment_tokenizer.DeTokenize(line)
- # Rejoin the lines back together.
- lines = line.split(TOKEN_LINES)
- return lines
- def usage():
- """Prints out usage information."""
- print 'Usage:'
- print ' ./cssjanus.py < file.css > file-rtl.css'
- print 'Flags:'
- print ' --swap_left_right_in_url: Fixes "left"/"right" string within urls.'
- print ' Ex: ./cssjanus.py --swap_left_right_in_url < file.css > file_rtl.css'
- print ' --swap_ltr_rtl_in_url: Fixes "ltr"/"rtl" string within urls.'
- print ' Ex: ./cssjanus --swap_ltr_rtl_in_url < file.css > file_rtl.css'
- def setflags(opts):
- """Parse the passed in command line arguments and set the FLAGS global.
- Args:
- opts: getopt iterable intercepted from argv.
- """
- global FLAGS
- # Parse the arguments.
- for opt, arg in opts:
- logging.debug('opt: %s, arg: %s' % (opt, arg))
- if opt in ("-h", "--help"):
- usage()
- sys.exit()
- elif opt in ("-d", "--debug"):
- logging.getLogger().setLevel(logging.DEBUG)
- elif opt == '--swap_ltr_rtl_in_url':
- FLAGS['swap_ltr_rtl_in_url'] = True
- elif opt == '--swap_left_right_in_url':
- FLAGS['swap_left_right_in_url'] = True
- def main(argv):
- """Sends stdin lines to ChangeLeftToRightToLeft and writes to stdout."""
- # Define the flags.
- try:
- opts, args = getopt.getopt(argv, 'hd', ['help', 'debug',
- 'swap_left_right_in_url',
- 'swap_ltr_rtl_in_url'])
- except getopt.GetoptError:
- usage()
- sys.exit(2)
- # Parse and set the flags.
- setflags(opts)
- # Call the main routine with all our functionality.
- fixed_lines = ChangeLeftToRightToLeft(sys.stdin.readlines())
- sys.stdout.write(''.join(fixed_lines))
- if __name__ == '__main__':
- main(sys.argv[1:])