module Data.Time.Format.Parse.Class
    (
        -- * Parsing
        ParseNumericPadding(..),
        ParseTime(..),
        parseSpecifiers,
        timeSubstituteTimeSpecifier,
        timeParseTimeSpecifier,
        durationParseTimeSpecifier,
    )
    where

import Control.Applicative hiding (optional,many)
import Data.Char
import Data.Maybe
import Data.Time.Format.Locale
import Text.ParserCombinators.ReadP

data ParseNumericPadding = NoPadding | SpacePadding | ZeroPadding

-- | The class of types which can be parsed given a UNIX-style time format
-- string.
class ParseTime t where
    -- | @since 1.9.1
    substituteTimeSpecifier :: proxy t -> TimeLocale -> Char -> Maybe String
    substituteTimeSpecifier proxy t
_ TimeLocale
_ Char
_ = Maybe String
forall a. Maybe a
Nothing
    -- | Get the string corresponding to the given format specifier.
    --
    -- @since 1.9.1
    parseTimeSpecifier :: proxy t -> TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
    -- | Builds a time value from a parsed input string.
    -- If the input does not include all the information needed to
    -- construct a complete value, any missing parts should be taken
    -- from 1970-01-01 00:00:00 +0000 (which was a Thursday).
    -- In the absence of @%C@ or @%Y@, century is 1969 - 2068.
    --
    -- @since 1.9.1
    buildTime :: TimeLocale -- ^ The time locale.
              -> [(Char,String)] -- ^ Pairs of format characters and the
                                 -- corresponding part of the input.
              -> Maybe t

-- | Case-insensitive version of 'Text.ParserCombinators.ReadP.char'.
charCI :: Char -> ReadP Char
charCI :: Char -> ReadP Char
charCI Char
c = (Char -> Bool) -> ReadP Char
satisfy (\Char
x -> Char -> Char
toUpper Char
c Char -> Char -> Bool
forall a. Eq a => a -> a -> Bool
== Char -> Char
toUpper Char
x)

-- | Case-insensitive version of 'Text.ParserCombinators.ReadP.string'.
stringCI :: String -> ReadP String
stringCI :: String -> ReadP String
stringCI String
this = do
    let
        scan :: String -> String -> ReadP String
scan [] String
_ = String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return String
this
        scan (Char
x:String
xs) (Char
y:String
ys) | Char -> Char
toUpper Char
x Char -> Char -> Bool
forall a. Eq a => a -> a -> Bool
== Char -> Char
toUpper Char
y = do
            Char
_ <- ReadP Char
get
            String -> String -> ReadP String
scan String
xs String
ys
        scan String
_ String
_ = ReadP String
forall a. ReadP a
pfail
    String
s <- ReadP String
look
    String -> String -> ReadP String
scan String
this String
s

parseSpecifiers :: ParseTime t => proxy t -> TimeLocale -> String -> ReadP [(Char,String)]
parseSpecifiers :: proxy t -> TimeLocale -> String -> ReadP [(Char, String)]
parseSpecifiers proxy t
pt TimeLocale
locale = let
    parse :: String -> ReadP [(Char,String)]
    parse :: String -> ReadP [(Char, String)]
parse [] = [(Char, String)] -> ReadP [(Char, String)]
forall (m :: * -> *) a. Monad m => a -> m a
return []
    parse (Char
'%':String
cs) = String -> ReadP [(Char, String)]
parse1 String
cs
    parse (Char
c:String
cs) | Char -> Bool
isSpace Char
c = do
        Char
_ <- (Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isSpace
        case String
cs of
            (Char
c':String
_) | Char -> Bool
isSpace Char
c' -> () -> ReadP ()
forall (m :: * -> *) a. Monad m => a -> m a
return ()
            String
_ -> ReadP ()
skipSpaces
        String -> ReadP [(Char, String)]
parse String
cs
    parse (Char
c:String
cs) = do
        Char
_ <- Char -> ReadP Char
charCI Char
c
        String -> ReadP [(Char, String)]
parse String
cs

    parse1 :: String -> ReadP [(Char,String)]
    parse1 :: String -> ReadP [(Char, String)]
parse1 (Char
'-':String
cs) = Maybe ParseNumericPadding -> String -> ReadP [(Char, String)]
parse2 (ParseNumericPadding -> Maybe ParseNumericPadding
forall a. a -> Maybe a
Just ParseNumericPadding
NoPadding) String
cs
    parse1 (Char
'_':String
cs) = Maybe ParseNumericPadding -> String -> ReadP [(Char, String)]
parse2 (ParseNumericPadding -> Maybe ParseNumericPadding
forall a. a -> Maybe a
Just ParseNumericPadding
SpacePadding) String
cs
    parse1 (Char
'0':String
cs) = Maybe ParseNumericPadding -> String -> ReadP [(Char, String)]
parse2 (ParseNumericPadding -> Maybe ParseNumericPadding
forall a. a -> Maybe a
Just ParseNumericPadding
ZeroPadding) String
cs
    parse1 String
cs = Maybe ParseNumericPadding -> String -> ReadP [(Char, String)]
parse2 Maybe ParseNumericPadding
forall a. Maybe a
Nothing String
cs

    parse2 :: Maybe ParseNumericPadding -> String -> ReadP [(Char,String)]
    parse2 :: Maybe ParseNumericPadding -> String -> ReadP [(Char, String)]
parse2 Maybe ParseNumericPadding
mpad (Char
'E':String
cs) = Maybe ParseNumericPadding
-> Bool -> String -> ReadP [(Char, String)]
parse3 Maybe ParseNumericPadding
mpad Bool
True String
cs
    parse2 Maybe ParseNumericPadding
mpad String
cs = Maybe ParseNumericPadding
-> Bool -> String -> ReadP [(Char, String)]
parse3 Maybe ParseNumericPadding
mpad Bool
False String
cs

    parse3 :: Maybe ParseNumericPadding -> Bool -> String -> ReadP [(Char,String)]
    parse3 :: Maybe ParseNumericPadding
-> Bool -> String -> ReadP [(Char, String)]
parse3 Maybe ParseNumericPadding
_ Bool
_ (Char
'%':String
cs) = do
        Char
_ <- Char -> ReadP Char
char Char
'%'
        String -> ReadP [(Char, String)]
parse String
cs
    parse3 Maybe ParseNumericPadding
_ Bool
_ (Char
c:String
cs) | Just String
s <- proxy t -> TimeLocale -> Char -> Maybe String
forall t (proxy :: * -> *).
ParseTime t =>
proxy t -> TimeLocale -> Char -> Maybe String
substituteTimeSpecifier proxy t
pt TimeLocale
locale Char
c = String -> ReadP [(Char, String)]
parse (String -> ReadP [(Char, String)])
-> String -> ReadP [(Char, String)]
forall a b. (a -> b) -> a -> b
$ String
s String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
cs
    parse3 Maybe ParseNumericPadding
mpad Bool
_alt (Char
c:String
cs) = do
        String
str <- proxy t
-> TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
forall t (proxy :: * -> *).
ParseTime t =>
proxy t
-> TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
parseTimeSpecifier proxy t
pt TimeLocale
locale Maybe ParseNumericPadding
mpad Char
c
        [(Char, String)]
specs <- String -> ReadP [(Char, String)]
parse String
cs
        [(Char, String)] -> ReadP [(Char, String)]
forall (m :: * -> *) a. Monad m => a -> m a
return ([(Char, String)] -> ReadP [(Char, String)])
-> [(Char, String)] -> ReadP [(Char, String)]
forall a b. (a -> b) -> a -> b
$ (Char
c,String
str) (Char, String) -> [(Char, String)] -> [(Char, String)]
forall a. a -> [a] -> [a]
: [(Char, String)]
specs
    parse3 Maybe ParseNumericPadding
_ Bool
_ [] = [(Char, String)] -> ReadP [(Char, String)]
forall (m :: * -> *) a. Monad m => a -> m a
return []
    in String -> ReadP [(Char, String)]
parse

parsePaddedDigits :: ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits :: ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits ParseNumericPadding
ZeroPadding Int
n = Int -> ReadP Char -> ReadP String
forall a. Int -> ReadP a -> ReadP [a]
count Int
n ((Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isDigit)
parsePaddedDigits ParseNumericPadding
SpacePadding Int
_n = ReadP ()
skipSpaces ReadP () -> ReadP String -> ReadP String
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> ReadP Char -> ReadP String
forall a. ReadP a -> ReadP [a]
many1 ((Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isDigit)
parsePaddedDigits ParseNumericPadding
NoPadding Int
_n = ReadP Char -> ReadP String
forall a. ReadP a -> ReadP [a]
many1 ((Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isDigit)

parsePaddedSignedDigits :: ParseNumericPadding -> Int -> ReadP String
parsePaddedSignedDigits :: ParseNumericPadding -> Int -> ReadP String
parsePaddedSignedDigits ParseNumericPadding
pad Int
n = do
    String
sign <- String -> ReadP String -> ReadP String
forall a. a -> ReadP a -> ReadP a
option String
"" (ReadP String -> ReadP String) -> ReadP String -> ReadP String
forall a b. (a -> b) -> a -> b
$ Char -> ReadP Char
char Char
'-' ReadP Char -> ReadP String -> ReadP String
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return String
"-"
    String
digits <- ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits ParseNumericPadding
pad Int
n
    String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return (String -> ReadP String) -> String -> ReadP String
forall a b. (a -> b) -> a -> b
$ String
sign String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
digits

parseSignedDecimal :: ReadP String
parseSignedDecimal :: ReadP String
parseSignedDecimal = do
    String
sign <- String -> ReadP String -> ReadP String
forall a. a -> ReadP a -> ReadP a
option String
"" (ReadP String -> ReadP String) -> ReadP String -> ReadP String
forall a b. (a -> b) -> a -> b
$ Char -> ReadP Char
char Char
'-' ReadP Char -> ReadP String -> ReadP String
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return String
"-"
    ReadP ()
skipSpaces
    String
digits <- ReadP Char -> ReadP String
forall a. ReadP a -> ReadP [a]
many1 (ReadP Char -> ReadP String) -> ReadP Char -> ReadP String
forall a b. (a -> b) -> a -> b
$ (Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isDigit
    String
decimaldigits <- String -> ReadP String -> ReadP String
forall a. a -> ReadP a -> ReadP a
option String
"" (ReadP String -> ReadP String) -> ReadP String -> ReadP String
forall a b. (a -> b) -> a -> b
$ do
        Char
_ <- Char -> ReadP Char
char Char
'.'
        String
dd <- ReadP Char -> ReadP String
forall a. ReadP a -> ReadP [a]
many (ReadP Char -> ReadP String) -> ReadP Char -> ReadP String
forall a b. (a -> b) -> a -> b
$ (Char -> Bool) -> ReadP Char
satisfy Char -> Bool
isDigit
        String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return (String -> ReadP String) -> String -> ReadP String
forall a b. (a -> b) -> a -> b
$ Char
'.'Char -> String -> String
forall a. a -> [a] -> [a]
:String
dd
    String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return (String -> ReadP String) -> String -> ReadP String
forall a b. (a -> b) -> a -> b
$ String
sign String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
digits String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
decimaldigits

timeParseTimeSpecifier :: TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
timeParseTimeSpecifier :: TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
timeParseTimeSpecifier TimeLocale
l Maybe ParseNumericPadding
mpad Char
c = let
    digits :: ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
pad = ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits (ParseNumericPadding
-> Maybe ParseNumericPadding -> ParseNumericPadding
forall a. a -> Maybe a -> a
fromMaybe ParseNumericPadding
pad Maybe ParseNumericPadding
mpad)
    oneOf :: [String] -> ReadP String
oneOf = [ReadP String] -> ReadP String
forall a. [ReadP a] -> ReadP a
choice ([ReadP String] -> ReadP String)
-> ([String] -> [ReadP String]) -> [String] -> ReadP String
forall b c a. (b -> c) -> (a -> b) -> a -> c
. (String -> ReadP String) -> [String] -> [ReadP String]
forall a b. (a -> b) -> [a] -> [b]
map String -> ReadP String
stringCI
    numericTZ :: ReadP String
numericTZ = do
        Char
s <- [ReadP Char] -> ReadP Char
forall a. [ReadP a] -> ReadP a
choice [Char -> ReadP Char
char Char
'+', Char -> ReadP Char
char Char
'-']
        String
h <- ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits ParseNumericPadding
ZeroPadding Int
2
        ReadP Char -> ReadP ()
forall a. ReadP a -> ReadP ()
optional (Char -> ReadP Char
char Char
':')
        String
m <- ParseNumericPadding -> Int -> ReadP String
parsePaddedDigits ParseNumericPadding
ZeroPadding Int
2
        String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return (Char
sChar -> String -> String
forall a. a -> [a] -> [a]
:String
hString -> String -> String
forall a. [a] -> [a] -> [a]
++String
m)
    in case Char
c of
        -- century
        Char
'C' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
2
        Char
'f' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
2

        -- year
        Char
'Y' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
4
        Char
'G' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
4

        -- year of century
        Char
'y' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'g' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2

        -- month of year
        Char
'B' -> [String] -> ReadP String
oneOf (((String, String) -> String) -> [(String, String)] -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (String, String) -> String
forall a b. (a, b) -> a
fst (TimeLocale -> [(String, String)]
months TimeLocale
l))
        Char
'b' -> [String] -> ReadP String
oneOf (((String, String) -> String) -> [(String, String)] -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (String, String) -> String
forall a b. (a, b) -> b
snd (TimeLocale -> [(String, String)]
months TimeLocale
l))
        Char
'm' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2

        -- day of month
        Char
'd' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'e' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
2

        -- week of year
        Char
'V' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'U' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'W' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2

        -- day of week
        Char
'u' -> [String] -> ReadP String
oneOf ([String] -> ReadP String) -> [String] -> ReadP String
forall a b. (a -> b) -> a -> b
$ (Char -> String) -> String -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (Char -> String -> String
forall a. a -> [a] -> [a]
:[]) [Char
'1'..Char
'7']
        Char
'a' -> [String] -> ReadP String
oneOf (((String, String) -> String) -> [(String, String)] -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (String, String) -> String
forall a b. (a, b) -> b
snd (TimeLocale -> [(String, String)]
wDays TimeLocale
l))
        Char
'A' -> [String] -> ReadP String
oneOf (((String, String) -> String) -> [(String, String)] -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (String, String) -> String
forall a b. (a, b) -> a
fst (TimeLocale -> [(String, String)]
wDays TimeLocale
l))
        Char
'w' -> [String] -> ReadP String
oneOf ([String] -> ReadP String) -> [String] -> ReadP String
forall a b. (a -> b) -> a -> b
$ (Char -> String) -> String -> [String]
forall a b. (a -> b) -> [a] -> [b]
map (Char -> String -> String
forall a. a -> [a] -> [a]
:[]) [Char
'0'..Char
'6']

        -- day of year
        Char
'j' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
3

        -- dayhalf of day (i.e. AM or PM)
        Char
'P' -> [String] -> ReadP String
oneOf (let (String
am,String
pm) = TimeLocale -> (String, String)
amPm TimeLocale
l in [String
am, String
pm])
        Char
'p' -> [String] -> ReadP String
oneOf (let (String
am,String
pm) = TimeLocale -> (String, String)
amPm TimeLocale
l in [String
am, String
pm])

        -- hour of day (i.e. 24h)
        Char
'H' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'k' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
2

        -- hour of dayhalf (i.e. 12h)
        Char
'I' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2
        Char
'l' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
SpacePadding Int
2

        -- minute of hour
        Char
'M' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2

        -- second of minute
        Char
'S' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
2

        -- picosecond of second
        Char
'q' -> ParseNumericPadding -> Int -> ReadP String
digits ParseNumericPadding
ZeroPadding Int
12
        Char
'Q' -> (Char -> String -> String)
-> ReadP Char -> ReadP String -> ReadP String
forall (f :: * -> *) a b c.
Applicative f =>
(a -> b -> c) -> f a -> f b -> f c
liftA2 (:) (Char -> ReadP Char
char Char
'.') ((Char -> Bool) -> ReadP String
munch Char -> Bool
isDigit) ReadP String -> ReadP String -> ReadP String
forall a. ReadP a -> ReadP a -> ReadP a
<++ String -> ReadP String
forall (m :: * -> *) a. Monad m => a -> m a
return String
""

        -- time zone
        Char
'z' -> ReadP String
numericTZ
        Char
'Z' -> (Char -> Bool) -> ReadP String
munch1 Char -> Bool
isAlpha ReadP String -> ReadP String -> ReadP String
forall a. ReadP a -> ReadP a -> ReadP a
<++
             ReadP String
numericTZ

        -- seconds since epoch
        Char
's' -> (Char -> ReadP Char
char Char
'-' ReadP Char -> ReadP String -> ReadP String
forall (m :: * -> *) a b. Monad m => m a -> m b -> m b
>> (String -> String) -> ReadP String -> ReadP String
forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap (Char
'-'Char -> String -> String
forall a. a -> [a] -> [a]
:) ((Char -> Bool) -> ReadP String
munch1 Char -> Bool
isDigit))
             ReadP String -> ReadP String -> ReadP String
forall a. ReadP a -> ReadP a -> ReadP a
<++ (Char -> Bool) -> ReadP String
munch1 Char -> Bool
isDigit

        Char
_   -> String -> ReadP String
forall (m :: * -> *) a. MonadFail m => String -> m a
fail (String -> ReadP String) -> String -> ReadP String
forall a b. (a -> b) -> a -> b
$ String
"Unknown format character: " String -> String -> String
forall a. [a] -> [a] -> [a]
++ Char -> String
forall a. Show a => a -> String
show Char
c

timeSubstituteTimeSpecifier :: TimeLocale -> Char -> Maybe String
timeSubstituteTimeSpecifier :: TimeLocale -> Char -> Maybe String
timeSubstituteTimeSpecifier TimeLocale
l Char
'c' = String -> Maybe String
forall a. a -> Maybe a
Just (String -> Maybe String) -> String -> Maybe String
forall a b. (a -> b) -> a -> b
$ TimeLocale -> String
dateTimeFmt TimeLocale
l
timeSubstituteTimeSpecifier TimeLocale
_ Char
'R' = String -> Maybe String
forall a. a -> Maybe a
Just String
"%H:%M"
timeSubstituteTimeSpecifier TimeLocale
_ Char
'T' = String -> Maybe String
forall a. a -> Maybe a
Just String
"%H:%M:%S"
timeSubstituteTimeSpecifier TimeLocale
l Char
'X' = String -> Maybe String
forall a. a -> Maybe a
Just (String -> Maybe String) -> String -> Maybe String
forall a b. (a -> b) -> a -> b
$ TimeLocale -> String
timeFmt TimeLocale
l
timeSubstituteTimeSpecifier TimeLocale
l Char
'r' = String -> Maybe String
forall a. a -> Maybe a
Just (String -> Maybe String) -> String -> Maybe String
forall a b. (a -> b) -> a -> b
$ TimeLocale -> String
time12Fmt TimeLocale
l
timeSubstituteTimeSpecifier TimeLocale
_ Char
'D' = String -> Maybe String
forall a. a -> Maybe a
Just String
"%m/%d/%y"
timeSubstituteTimeSpecifier TimeLocale
_ Char
'F' = String -> Maybe String
forall a. a -> Maybe a
Just String
"%Y-%m-%d"
timeSubstituteTimeSpecifier TimeLocale
l Char
'x' = String -> Maybe String
forall a. a -> Maybe a
Just (String -> Maybe String) -> String -> Maybe String
forall a b. (a -> b) -> a -> b
$ TimeLocale -> String
dateFmt TimeLocale
l
timeSubstituteTimeSpecifier TimeLocale
_ Char
'h' = String -> Maybe String
forall a. a -> Maybe a
Just String
"%b"
timeSubstituteTimeSpecifier TimeLocale
_  Char
_ = Maybe String
forall a. Maybe a
Nothing

durationParseTimeSpecifier :: TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
durationParseTimeSpecifier :: TimeLocale -> Maybe ParseNumericPadding -> Char -> ReadP String
durationParseTimeSpecifier TimeLocale
_ Maybe ParseNumericPadding
mpad Char
c = let
    padopt :: Int -> ReadP String
padopt = ParseNumericPadding -> Int -> ReadP String
parsePaddedSignedDigits (ParseNumericPadding -> Int -> ReadP String)
-> ParseNumericPadding -> Int -> ReadP String
forall a b. (a -> b) -> a -> b
$ ParseNumericPadding
-> Maybe ParseNumericPadding -> ParseNumericPadding
forall a. a -> Maybe a -> a
fromMaybe ParseNumericPadding
NoPadding Maybe ParseNumericPadding
mpad
    in case Char
c of
        Char
'y' -> Int -> ReadP String
padopt Int
1
        Char
'b' -> Int -> ReadP String
padopt Int
1
        Char
'B' -> Int -> ReadP String
padopt Int
2
        Char
'w' -> Int -> ReadP String
padopt Int
1
        Char
'd' -> Int -> ReadP String
padopt Int
1
        Char
'D' -> Int -> ReadP String
padopt Int
1
        Char
'h' -> Int -> ReadP String
padopt Int
1
        Char
'H' -> Int -> ReadP String
padopt Int
2
        Char
'm' -> Int -> ReadP String
padopt Int
1
        Char
'M' -> Int -> ReadP String
padopt Int
2
        Char
's' -> ReadP String
parseSignedDecimal
        Char
'S' -> ReadP String
parseSignedDecimal
        Char
_   -> String -> ReadP String
forall (m :: * -> *) a. MonadFail m => String -> m a
fail (String -> ReadP String) -> String -> ReadP String
forall a b. (a -> b) -> a -> b
$ String
"Unknown format character: " String -> String -> String
forall a. [a] -> [a] -> [a]
++ Char -> String
forall a. Show a => a -> String
show Char
c