Merge branch 'encukou'
[zzz-pokedex.git] / pokedex / db / markdown.py
1 # encoding: utf8
2 u"""Implements the markup used for description and effect text in the database.
3
4 The language used is a variation of Markdown and Markdown Extra. There are
5 docs for each at http://daringfireball.net/projects/markdown/ and
6 http://michelf.com/projects/php-markdown/extra/ respectively.
7
8 Pokédex links are represented with the extended syntax `[name]{type}`, e.g.,
9 `[Eevee]{pokemon}`. The actual code that parses these is in spline-pokedex.
10 """
11 from __future__ import absolute_import
12
13 import markdown
14 import sqlalchemy.types
15
16 class MarkdownString(object):
17 """Wraps a Markdown string. Stringifies to the original text, but .as_html
18 will return an HTML rendering.
19
20 To add extensions to the rendering (which is necessary for rendering links
21 correctly, and which spline-pokedex does), you must append to this class's
22 `markdown_extensions` list. Yep, that's gross.
23 """
24
25 markdown_extensions = ['extra']
26
27 def __init__(self, source_text):
28 self.source_text = source_text
29 self._as_html = None
30
31 def __unicode__(self):
32 return self.source_text
33
34 @property
35 def as_html(self):
36 """Returns the string as HTML4."""
37
38 if self._as_html:
39 return self._as_html
40
41 md = markdown.Markdown(
42 extensions=self.markdown_extensions,
43 safe_mode='escape',
44 output_format='xhtml1',
45 )
46
47 self._as_html = md.convert(self.source_text)
48
49 return self._as_html
50
51 @property
52 def as_text(self):
53 """Returns the string in a plaintext-friendly form.
54
55 At the moment, this is just the original source text.
56 """
57 return self.source_text
58
59 def _markdownify_effect_text(move, effect_text):
60 effect_text = effect_text.replace(
61 u'$effect_chance',
62 unicode(move.effect_chance),
63 )
64
65 return MarkdownString(effect_text)
66
67 class MoveEffectProperty(object):
68 """Property that wraps move effects. Used like this:
69
70 MoveClass.effect = MoveEffectProperty('effect')
71
72 some_move.effect # returns a MarkdownString
73 some_move.effect.as_html # returns a chunk of HTML
74
75 This class also performs simple substitution on the effect, replacing
76 `$effect_chance` with the move's actual effect chance.
77
78 Use `MoveEffectPropertyMap` for dict-like association proxies.
79 """
80
81 def __init__(self, effect_column):
82 self.effect_column = effect_column
83
84 def __get__(self, obj, cls):
85 prop = getattr(obj.move_effect, self.effect_column)
86 return _markdownify_effect_text(obj, prop)
87
88 class MoveEffectPropertyMap(MoveEffectProperty):
89 """Similar to `MoveEffectProperty`, but works on dict-like association
90 proxies.
91 """
92 def __get__(self, obj, cls):
93 prop = getattr(obj.move_effect, self.effect_column)
94 newdict = dict(prop)
95 for key in newdict:
96 newdict[key] = _markdownify_effect_text(obj, newdict[key])
97 return newdict
98
99 class MarkdownColumn(sqlalchemy.types.TypeDecorator):
100 """Generic SQLAlchemy column type for Markdown text.
101
102 Do NOT use this for move effects! They need to know what move they belong
103 to so they can fill in, e.g., effect chances. Use the MoveEffectProperty
104 property class above.
105 """
106 impl = sqlalchemy.types.Unicode
107
108 def process_bind_param(self, value, dialect):
109 if value is None:
110 return None
111
112 if not isinstance(value, basestring):
113 # Can't assign, e.g., MarkdownString objects yet
114 raise NotImplementedError
115
116 return unicode(value)
117
118 def process_result_value(self, value, dialect):
119 if value is None:
120 return None
121
122 return MarkdownString(value)