module Network.Wai.Logger.IP (
    NumericAddress,
    showSockAddr,
) where

import Data.Bits (shift, (.&.))
import Data.Word (Word32)
import Network.Socket (SockAddr (..))
import System.ByteOrder (ByteOrder (..), byteOrder)
import Text.Printf (printf)

-- |  A type for IP address in numeric string representation.
type NumericAddress = String

showIPv4 :: Word32 -> Bool -> NumericAddress
showIPv4 :: Word32 -> Bool -> String
showIPv4 Word32
w32 Bool
little
    | Bool
little = Word32 -> String
forall a. Show a => a -> String
show Word32
b1 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b2 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b3 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b4
    | Bool
otherwise = Word32 -> String
forall a. Show a => a -> String
show Word32
b4 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b3 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b2 String -> String -> String
forall a. [a] -> [a] -> [a]
++ String
"." String -> String -> String
forall a. [a] -> [a] -> [a]
++ Word32 -> String
forall a. Show a => a -> String
show Word32
b1
  where
    t1 :: Word32
t1 = Word32
w32
    t2 :: Word32
t2 = Word32 -> Int -> Word32
forall a. Bits a => a -> Int -> a
shift Word32
t1 (-Int
8)
    t3 :: Word32
t3 = Word32 -> Int -> Word32
forall a. Bits a => a -> Int -> a
shift Word32
t2 (-Int
8)
    t4 :: Word32
t4 = Word32 -> Int -> Word32
forall a. Bits a => a -> Int -> a
shift Word32
t3 (-Int
8)
    b1 :: Word32
b1 = Word32
t1 Word32 -> Word32 -> Word32
forall a. Bits a => a -> a -> a
.&. Word32
0x000000ff
    b2 :: Word32
b2 = Word32
t2 Word32 -> Word32 -> Word32
forall a. Bits a => a -> a -> a
.&. Word32
0x000000ff
    b3 :: Word32
b3 = Word32
t3 Word32 -> Word32 -> Word32
forall a. Bits a => a -> a -> a
.&. Word32
0x000000ff
    b4 :: Word32
b4 = Word32
t4 Word32 -> Word32 -> Word32
forall a. Bits a => a -> a -> a
.&. Word32
0x000000ff

showIPv6 :: (Word32, Word32, Word32, Word32) -> String
showIPv6 :: (Word32, Word32, Word32, Word32) -> String
showIPv6 (Word32
w1, Word32
w2, Word32
w3, Word32
w4) =
    String
-> Word32
-> Word32
-> Word32
-> Word32
-> Word32
-> Word32
-> Word32
-> Word32
-> String
forall r. PrintfType r => String -> r
printf String
"%x:%x:%x:%x:%x:%x:%x:%x" Word32
s1 Word32
s2 Word32
s3 Word32
s4 Word32
s5 Word32
s6 Word32
s7 Word32
s8
  where
    (Word32
s1, Word32
s2) = Word32 -> (Word32, Word32)
forall {b}. (Bits b, Num b) => b -> (b, b)
split16 Word32
w1
    (Word32
s3, Word32
s4) = Word32 -> (Word32, Word32)
forall {b}. (Bits b, Num b) => b -> (b, b)
split16 Word32
w2
    (Word32
s5, Word32
s6) = Word32 -> (Word32, Word32)
forall {b}. (Bits b, Num b) => b -> (b, b)
split16 Word32
w3
    (Word32
s7, Word32
s8) = Word32 -> (Word32, Word32)
forall {b}. (Bits b, Num b) => b -> (b, b)
split16 Word32
w4
    split16 :: b -> (b, b)
split16 b
w = (b
h1, b
h2)
      where
        h1 :: b
h1 = b -> Int -> b
forall a. Bits a => a -> Int -> a
shift b
w (-Int
16) b -> b -> b
forall a. Bits a => a -> a -> a
.&. b
0x0000ffff
        h2 :: b
h2 = b
w b -> b -> b
forall a. Bits a => a -> a -> a
.&. b
0x0000ffff

-- | Convert 'SockAddr' to 'NumericAddress'. If the address is
--   IPv4-embedded IPv6 address, the IPv4 is extracted.
showSockAddr :: SockAddr -> NumericAddress
-- HostAddr is network byte order.
showSockAddr :: SockAddr -> String
showSockAddr (SockAddrInet PortNumber
_ Word32
addr4) = Word32 -> Bool -> String
showIPv4 Word32
addr4 (ByteOrder
byteOrder ByteOrder -> ByteOrder -> Bool
forall a. Eq a => a -> a -> Bool
== ByteOrder
LittleEndian)
-- HostAddr6 is host byte order.
showSockAddr (SockAddrInet6 PortNumber
_ Word32
_ (Word32
0, Word32
0, Word32
0x0000ffff, Word32
addr4) Word32
_) = Word32 -> Bool -> String
showIPv4 Word32
addr4 Bool
False
showSockAddr (SockAddrInet6 PortNumber
_ Word32
_ (Word32
0, Word32
0, Word32
0, Word32
1) Word32
_) = String
"::1"
showSockAddr (SockAddrInet6 PortNumber
_ Word32
_ (Word32, Word32, Word32, Word32)
addr6 Word32
_) = (Word32, Word32, Word32, Word32) -> String
showIPv6 (Word32, Word32, Word32, Word32)
addr6
showSockAddr (SockAddrUnix String
_) = String
"-"