python-oxlib/oxlib/text.py

# -*- coding: utf-8 -*-
# vi:si:et:sw=4:sts=4:ts=4
# GPL 2008
import math
import re


def findRe(string, regexp):
    result = re.compile(regexp, re.DOTALL).findall(string)
    if result:
        return result[0].strip()
    return ''

def findString(string, string0='', string1 = ''):
    """Return the string between string0 and string1. 

    If string0 or string1 is left out, begining or end of string is used.

    >>> findString('i am not there', string1=' not there')
    'i am'

    >>> findString('i am not there', 'i am ', ' there')
    'not'

    >>> findString('i am not there', 'i am not t')
    'here'

    """
    if string0:
        string0 = re.escape(string0)
    else:
        string0 = '^'
    if string1:
        string1 = re.escape(string1)
    else:
        string1 = '$'
    return findRe(string, string0 + '(.*?)' + string1)

def removeSpecialCharacters(text):
    """
    Removes special characters inserted by Word.
    """
    text = text.replace(u'\u2013', '-')
    text = text.replace(u'\u2026O', "'")
    text = text.replace(u'\u2019', "'")
    text = text.replace(u'', "'")
    text = text.replace(u'', "'")
    text = text.replace(u'', "-")
    return text

def wrap(text, width):
    """
    A word-wrap function that preserves existing line breaks and most spaces in
    the text. Expects that existing line breaks are posix newlines (\n).
    See http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/148061
    """
    return reduce(lambda line, word, width=width: '%s%s%s' %
                  (line,
                    ' \n'[(len(line[line.rfind('\n')+1:])
                          + len(word.split('\n',1)[0]
                              ) >= width)],
                    word),
                  text.split(' ')
                  )

def wrapString(string, length=80, separator='\n', balance=False):
    '''
    >>> wrapString(u"Anticonstitutionellement, Paris s'eveille", 16)
    u"Anticonstitution\\nellement, Paris \\ns'eveille"
    >>> wrapString(u'All you can eat', 12, '\\n', True)
    u'All you \\ncan eat'
    '''
    words = string.split(' ')
    if balance:
        # balance lines: test if same number of lines
        # can be achieved with a shorter line length
        lines = wrapString(string, length, separator, False).split(separator)
        if len(lines) > 1:
            while length > max(map(lambda x : len(x), words)):
                length -= 1
                if len(wrapString(string, length, separator, False).split(separator)) > len(lines):
                    length += 1
                    break
    lines = ['']
    for word in words:
        if len(lines[len(lines) - 1] + word + u' ') <= length + 1:
            # word fits in current line
            lines[len(lines) - 1] += word + u' ';
        else:
            if len(word) <= length:
                # word fits in next line
                lines.append(word + u' ')
            else:
                # word is longer than line
                position = length - len(lines[len(lines) - 1])
                lines[len(lines) - 1] += word[0:position]
                for i in range(position, len(word), length):
                    lines.append(word[i:i+length]);
                lines[len(lines) - 1] += u' '
    return separator.join(lines).strip()

def truncateString(string, length, padding='...', position='right'):
    #  >>> truncateString('anticonstitutionellement', 16, '...', 'left')
    #  '...utionellement'
    #  >>> truncateString('anticonstitutionellement', 16, '...', 'center')
    #  'anticon...lement'
    #  >>> truncateString('anticonstitutionellement', 16, '...', 'right')
    #  'anticonstitut...'
    stringLength = len(string);
    paddingLength = len(padding)
    if stringLength > length:
        if position == 'left':
            string = '%s%s' % (padding, string[stringLength + paddingLength - length:])
        elif position == 'center':
            left = int(math.ceil(float(length - paddingLength) / 2))
            right = int(stringLength - math.floor(float(length - paddingLength) / 2))
            string = '%s%s%s' % (string[:left], padding, string[right:])
        elif position == 'right':
            string = '%s%s' % (string[:length - paddingLength], padding)
    return string;

def truncateWords(s, num):
    """Truncates a string after a certain number of chacters, but ends with a word

    >>> truncateString('Truncates a string after a certain number of chacters, but ends with a word', 23)
    'Truncates a string...'
    >>> truncateString('Truncates a string', 23)
    'Truncates a string'

    """
    length = int(num)
    if len(s) <= length:
        return s
    words = s.split()
    ts = ""
    while words and len(ts) + len(words[0]) < length:
        ts += " " + words.pop(0)
    if words:
        ts += "..."
    return ts.strip()

def trimString(string, num):
    """Truncates a string after a certain number of chacters, adding ... at -10 characters

    >>> trimString('Truncates a string after a certain number of chacters', 23)
    'Truncates ...f chacters'
    >>> trimString('Truncates a string', 23)
    'Truncates a string'
    """
    if len(string) > num:
        string = string[:num - 13] + '...' + string[-10:]
    return string

def truncateWords(s, num):
    "Truncates a string after a certain number of words."
    length = int(num)
    words = s.split()
    if len(words) > length:
        words = words[:length]
        if not words[-1].endswith('...'):
            words.append('...')
    return ' '.join(words)

def getValidFilename(s):
    """
    Returns the given string converted to a string that can be used for a clean
    filename. Specifically, leading and trailing spaces are removed; 
    all non-filename-safe characters are removed.

    >>> getValidFilename("john's portrait in 2004.jpg")
    'john_s_portrait_in_2004.jpg'
    """
    s = s.strip()
    s = s.replace(' ', '_')
    s = re.sub(r'[^-A-Za-z0-9_.\[\]\ ]', '_', s)
    s = s.replace('__', '_').replace('__', '_')
    return s

def getTextList(list_, last_word='or'):
    """
    >>> getTextList([u'a', u'b', u'c', u'd'])
    u'a, b, c or d'
    >>> getTextList([u'a', u'b', u'c'], 'and')
    u'a, b and c'
    >>> getTextList([u'a', u'b'], 'and')
    u'a and b'
    >>> getTextList([u'a'])
    u'a'
    >>> getTextList([])
    ''
    """
    if len(list_) == 0: return ''
    if len(list_) == 1: return list_[0]
    return u'%s %s %s' % (u', '.join([unicode(i) for i in list_][:-1]), last_word, list_[-1])

def getListText(text, last_word='or'):
    """
    >>> getListText(u'a, b, c or d')
    [u'a', u'b', u'c', u'd']
    >>> getListText(u'a, b and c', u'and')
    [u'a', u'b', u'c']
    >>> getListText(u'a and b', u'and')
    [u'a', u'b']
    >>> getListText(u'a')
    [u'a']
    >>> getListText(u'')
    []
    """
    list_ = []
    if text:
        list_ = text.split(u', ')
        if list_:
            i=len(list_)-1
            last = list_[i].split(last_word)
            if len(last) == 2:
                list_[i] = last[0].strip()
                list_.append(last[1].strip())
    return list_

def normalizeNewlines(text):
    return re.sub(r'\r\n|\r|\n', '\n', text)

def recapitalize(text):
    "Recapitalizes text, placing caps after end-of-sentence punctuation."
    #capwords = ()
    text = text.lower()
    capsRE = re.compile(r'(?:^|(?<=[\.\?\!] ))([a-z])')
    text = capsRE.sub(lambda x: x.group(1).upper(), text)
    #for capword in capwords:
    #    capwordRE = re.compile(r'\b%s\b' % capword, re.I)
    #    text = capwordRE.sub(capword, text)
    return text

def phone2numeric(phone):
    "Converts a phone number with letters into its numeric equivalent."
    letters = re.compile(r'[A-PR-Y]', re.I)
    char2number = lambda m: {'a': '2', 'c': '2', 'b': '2', 'e': '3',
          'd': '3', 'g': '4', 'f': '3', 'i': '4', 'h': '4', 'k': '5',
          'j': '5', 'm': '6', 'l': '5', 'o': '6', 'n': '6', 'p': '7',
          's': '7', 'r': '7', 'u': '8', 't': '8', 'w': '9', 'v': '8',
          'y': '9', 'x': '9'}.get(m.group(0).lower())
    return letters.sub(char2number, phone)

def compressString(s):
    import cStringIO, gzip
    zbuf = cStringIO.StringIO()
    zfile = gzip.GzipFile(mode='wb', compresslevel=6, fileobj=zbuf)
    zfile.write(s)
    zfile.close()
    return zbuf.getvalue()

smart_split_re = re.compile('("(?:[^"\\\\]*(?:\\\\.[^"\\\\]*)*)"|\'(?:[^\'\\\\]*(?:\\\\.[^\'\\\\]*)*)\'|[^\\s]+)')
def smartSplit(text):
    """
    Generator that splits a string by spaces, leaving quoted phrases together.
    Supports both single and double quotes, and supports escaping quotes with
    backslashes. In the output, strings will keep their initial and trailing
    quote marks.
    >>> list(smartSplit('This is "a person\\'s" test.'))
    ['This', 'is', '"a person\\'s"', 'test.']
    """
    for bit in smart_split_re.finditer(text):
        bit = bit.group(0)
        if bit[0] == '"':
            yield '"' + bit[1:-1].replace('\\"', '"').replace('\\\\', '\\') + '"'
        elif bit[0] == "'":
            yield "'" + bit[1:-1].replace("\\'", "'").replace("\\\\", "\\") + "'"
        else:
            yield bit