summaryrefslogtreecommitdiffstats
path: root/Scanner.hs
blob: df488688e4e4392940f3a17e1f4a64a65a8cf301 (plain)
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
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
{-# LANGUAGE LambdaCase #-}

module Scanner
    ( scan
    ) where

import Data.Bits ((.&.), testBit)
import Data.Char (ord)
import Data.Word (Word8)
import Event
import System.IO (Handle, hGetChar, hLookAhead, hWaitForInput)


timeout :: Int
timeout = 1


scan :: Handle -> IO Event
scan h =
    hGetChar h >>= \case
        '\ESC' -> scanESC h
        c -> return $ EKey [c]



scanESC :: Handle -> IO Event
scanESC h =
    hWaitGetChar timeout h >>= \case
        Nothing -> return $ EKey "\ESC"
        Just c
            | c == '[' -> -- 05/11
                scanCS h
            | c == '\ESC' -> -- 01/11
                -- XXX M-F1 and other crazy chords may cause
                -- \ESC\ESC... on wu, so we just recurse here...
                scanESC h
            | c == 'O' -> -- 04/15
                -- XXX Non-CSI SS3
                -- XXX finalByte is maybe calles somehow else here, but it's
                -- the same range
                one h finalByte ['O','\ESC'] >>=
                return . EKey . reverse
            | otherwise ->
                return $ EKey ['\ESC',c]


scanCS :: Handle -> IO Event
scanCS h =
    hWaitLookAhead timeout h >>= \case
        Nothing -> return $ EKey "\ESC" -- TODO move this to scanESC
        Just c
            | c == 'M' -> do
                _ <- hGetChar h -- drop 'M'
                b <- hGetChar h
                x <- hGetChar h
                y <- hGetChar h
                return $ parseNormalButton b x y
            | otherwise ->
                zeroOrMore h parameterByte ['[', '\ESC'] >>=
                zeroOrMore h intermediateByte >>=
                one h finalByte >>=
                return . EKey . reverse



zeroOrMore :: Handle -> (Char -> Bool) -> [Char] -> IO [Char]
zeroOrMore h p buf =
    hWaitLookAhead timeout h >>= \case
        Nothing -> return buf
        Just c
            | p c ->
                hGetChar h {-drop c-} >> zeroOrMore h p (c:buf)
            | otherwise ->
                return buf


one :: Handle -> (Char -> Bool) -> [Char] -> IO [Char]
one h p buf =
    hWaitLookAhead timeout h >>= \case
        Nothing -> return buf -- TODO error?
        Just c
            | p c -> do
                _ <- hGetChar h -- drop c
                return (c:buf)
            | otherwise ->
                error "expected one TODO"


parameterByte :: Char -> Bool
parameterByte = between '0' '?'     -- 03/00 03/15

intermediateByte :: Char -> Bool
intermediateByte = between ' ' '/'  -- 02/00 02/15

finalByte :: Char -> Bool
finalByte = between '@' '~'         -- 04/00 07/14


between :: Ord a => a -> a -> (a -> Bool)
between lo hi = \ x -> lo <= x && x <= hi


hWaitGetChar :: Int -> Handle -> IO (Maybe Char)
hWaitGetChar t h = do
    ready <- hWaitForInput h t
    if ready
        then hGetChar h >>= return . Just
        else return Nothing


hWaitLookAhead :: Int -> Handle -> IO (Maybe Char)
hWaitLookAhead t h = do
    ready <- hWaitForInput h t
    if ready
        then hLookAhead h >>= return . Just
        else return Nothing


parseNormalButton :: Char -> Char -> Char -> Event
parseNormalButton cb cx cy = do
    let b = fromIntegral $ ord cb :: Word8
        x = ord cx - 32
        y = ord cy - 32
        button = case (b .&. 3) + (b .&. 64) of
                0 -> 1
                1 -> 2
                2 -> 3
                3 -> 0 -- release
                64 -> 4 -- wheel up
                65 -> 5 -- wheel down
                66 -> 6 -- wheel left
                67 -> 7 -- wheel right
                _ -> error "TODO proper parseNormalButton error"
    EMouse $ MouseInfo
        { mouseButton  = button
        , mouseShift   = testBit b 2
        , mouseMeta    = testBit b 3
        , mouseControl = testBit b 4
        , mouseX       = x
        , mouseY       = y
        }