aboutsummaryrefslogtreecommitdiff
path: root/haddock-test/src/Test/Haddock/Xhtml.hs
blob: d8c2624977f2aff50154a8c5114d778e2e3681cf (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE StandaloneDeriving #-}


module Test.Haddock.Xhtml
    ( Xhtml(..)
    , parseXhtml, dumpXhtml
    , stripLinks, stripLinksWhen, stripAnchorsWhen, stripFooter
    ) where


import Data.Generics.Aliases
import Data.Generics.Schemes

import Text.XML.Light


newtype Xhtml = Xhtml
    { xhtmlElement :: Element
    } deriving Eq


-- TODO: Find a way to avoid warning about orphan instances.
deriving instance Eq Element
deriving instance Eq Content
deriving instance Eq CData


parseXhtml :: String -> Maybe Xhtml
parseXhtml = fmap Xhtml . parseXMLDoc


dumpXhtml :: Xhtml -> String
dumpXhtml = ppElement . xhtmlElement


stripLinks :: Xhtml -> Xhtml
stripLinks = stripLinksWhen (const True)


stripLinksWhen :: (String -> Bool) -> Xhtml -> Xhtml
stripLinksWhen p =
    processAnchors unlink
  where
    unlink attr@(Attr { attrKey = key, attrVal = val })
        | qName key == "href" && p val = attr { attrVal = "#" }
        | otherwise = attr


stripAnchorsWhen :: (String -> Bool) -> Xhtml -> Xhtml
stripAnchorsWhen p =
    processAnchors unname
  where
    unname attr@(Attr { attrKey = key, attrVal = val })
        | qName key == "name" && p val = attr { attrVal = "" }
        | otherwise = attr


processAnchors :: (Attr -> Attr) -> Xhtml -> Xhtml
processAnchors f = Xhtml . everywhere (mkT f) . xhtmlElement


stripFooter :: Xhtml -> Xhtml
stripFooter =
    Xhtml . everywhere (mkT defoot) . xhtmlElement
  where
    defoot el
        | isFooter el = el { elContent = [] }
        | otherwise = el
    isFooter el = any isFooterAttr $ elAttribs el
    isFooterAttr (Attr { .. }) = and
        [ qName attrKey == "id"
        , attrVal == "footer"
        ]