1 import difflib, string

     2 from django.utils.translation import ugettext as _

     3 

     4 def isatag(x): return x.startswith("<") and x.endswith(">")

     5 

     6 def text_diff(a, b):

     7     res = []

     8     a, b = createlist(a), createlist(b)

     9     s = difflib.SequenceMatcher(isatag, a, b)

    10     for e in s.get_opcodes():

    11         if e[0] == "replace":

    12             res.append('<del class="diff modified">'+''.join(a[e[1]:e[2]]) + '</del><ins class="diff modified">'+''.join(b[e[3]:e[4]])+"</ins>")

    13         elif e[0] == "delete":

    14             res.append('<del class="diff">'+ ''.join(a[e[1]:e[2]]) + "</del>")

    15         elif e[0] == "insert":

    16             res.append('<ins class="diff">'+''.join(b[e[3]:e[4]]) + "</ins>")

    17         elif e[0] == "equal":

    18             res.append(''.join(b[e[3]:e[4]]))

    19         else: 

    20             raise "error parsing %s" %(e[0])

    21     return ''.join(res)

    22 

    23 COLORS = [

    24 '#FF0000',

    25 '#EE0000',

    26 '#DD0000',

    27 '#CC0000',

    28 '#BB0000',

    29 '#AA0000',

    30 '#990000',

    31 '#880000',

    32 '#770000',

    33 ]

    34 

    35 from colorsys import hls_to_rgb, hsv_to_rgb

    36 

    37 def generatePastelColors(n):

    38     s = .4

    39     v = .99

    40     return ['#'+''.join((hex(int(r*255))[2:],hex(int(g*255))[2:],hex(int(b*255))[2:])) for r,g,b in [hsv_to_rgb(h/200.,s,v) for h in range(1,100,100/n)]]

    41     

    42 

    43 DEFAULT_COLOR = '#D9D9D9'

    44 def get_colors(authors, last_white = False):

    45     """

    46     returns a dict for authors's colors (with last one white if 'last_white')

    47     """

    48     authors = set(authors)

    49     #new_colors = list(tuple(COLORS))

    50     new_colors = generatePastelColors(len(set(authors)))

    51     res = []

    52     if None in authors or '' in authors:

    53         res = [(_(u'unknown'),DEFAULT_COLOR) ]

    54     res.extend([(author,new_colors.pop()) for author in authors if author])

    55     #if authors[-1]:

    56     #    res[authors[-1]] = '#FFFFFF'

    57     return res

    58     

    59 

    60 def text_history(versions, authors):

    61     res = versions[0]

    62     colors = get_colors(authors)

    63     for ind in range(len(versions)-1):

    64         author = authors[ind]

    65         color = colors.get(author,DEFAULT_COLOR)

    66         v_2 = versions[ind + 1]

    67         res = text_diff_add(v_2, res, color)

    68     return res,colors.items()

    69 

    70 from cm.utils.html import surrond_text_node

    71  

    72 def text_diff_add(a,b, color):

    73     res = []

    74     a, b = createlist(a), createlist(b)

    75     s = difflib.SequenceMatcher(isatag, a, b)

    76     for e in s.get_opcodes():

    77         if e[0] == "replace":

    78             html_chunk = ''.join(b[e[3]:e[4]])

    79             new_html_chunk = surrond_text_node(html_chunk,'<span style="background: %s;">' %color,'</span>')

    80             res.append(new_html_chunk)

    81             #res.append('<font style="background: %s;" class="diff modified">' %color+''.join(b[e[3]:e[4]])+"</font>")

    82         elif e[0] == "delete":

    83             pass

    84         elif e[0] == "insert":

    85             html_chunk = ''.join(b[e[3]:e[4]])

    86             new_html_chunk = surrond_text_node(html_chunk,'<span style="background: %s;">' %color,'</span>') 

    87             res.append(new_html_chunk)

    88             #res.append('<font style="background: %s;" class="diff">' %color+''.join(b[e[3]:e[4]]) + "</font>")

    89         elif e[0] == "equal":

    90             res.append(''.join(b[e[3]:e[4]]))

    91         else: 

    92             raise "error parsing %s" %(e[0])

    93     return ''.join(res)

    94 

    95 def createlist(x, b=0):

    96     mode = 'char'

    97     cur = ''

    98     out = []

    99     for c in x:

   100         if mode == 'tag':

   101             if c == '>': 

   102                 if b: cur += ']'

   103                 else: cur += c

   104                 out.append(cur); cur = ''; mode = 'char'

   105             else: cur += c

   106         elif mode == 'char':

   107             if c == '<': 

   108                 out.append(cur)

   109                 if b: cur = '['

   110                 else: cur = c

   111                 mode = 'tag'            

   112             elif c in string.whitespace: out.append(cur+c); cur = ''

   113             else: cur += c

   114     out.append(cur)

   115     return filter(lambda x: x is not '', out)