{-# LANGUAGE LambdaCase #-}
module Hpack.Error (
-- | /__NOTE:__/ This module is exposed to allow integration of Hpack into
-- other tools.  It is not meant for general use by end users.  The following
-- caveats apply:
--
-- * The API is undocumented, consult the source instead.
--
-- * The exposed types and functions primarily serve Hpack's own needs, not
-- that of a public API.  Breaking changes can happen as Hpack evolves.
--
-- As an Hpack user you either want to use the @hpack@ executable or a build
-- tool that supports Hpack (e.g. @stack@ or @cabal2nix@).
  HpackError (..)
, formatHpackError
, ProgramName (..)
, URL
, Status (..)
, formatStatus
) where

import qualified Data.ByteString.Char8 as B
import           Data.List (intercalate)
import           Data.String (IsString (..))
import           Data.Version (Version (..), showVersion)
import           Network.HTTP.Types.Status (Status (..))

type URL = String

data HpackError =
    HpackVersionNotSupported FilePath Version Version
  | DefaultsFileNotFound FilePath
  | DefaultsDownloadFailed URL Status
  | CycleInDefaults [FilePath]
  | ParseError String
  | DecodeValueError FilePath String
  deriving (HpackError -> HpackError -> Bool
(HpackError -> HpackError -> Bool)
-> (HpackError -> HpackError -> Bool) -> Eq HpackError
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: HpackError -> HpackError -> Bool
$c/= :: HpackError -> HpackError -> Bool
== :: HpackError -> HpackError -> Bool
$c== :: HpackError -> HpackError -> Bool
Eq, Int -> HpackError -> ShowS
[HpackError] -> ShowS
HpackError -> String
(Int -> HpackError -> ShowS)
-> (HpackError -> String)
-> ([HpackError] -> ShowS)
-> Show HpackError
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [HpackError] -> ShowS
$cshowList :: [HpackError] -> ShowS
show :: HpackError -> String
$cshow :: HpackError -> String
showsPrec :: Int -> HpackError -> ShowS
$cshowsPrec :: Int -> HpackError -> ShowS
Show)

newtype ProgramName = ProgramName {ProgramName -> String
unProgramName :: String}
  deriving (ProgramName -> ProgramName -> Bool
(ProgramName -> ProgramName -> Bool)
-> (ProgramName -> ProgramName -> Bool) -> Eq ProgramName
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: ProgramName -> ProgramName -> Bool
$c/= :: ProgramName -> ProgramName -> Bool
== :: ProgramName -> ProgramName -> Bool
$c== :: ProgramName -> ProgramName -> Bool
Eq, Int -> ProgramName -> ShowS
[ProgramName] -> ShowS
ProgramName -> String
(Int -> ProgramName -> ShowS)
-> (ProgramName -> String)
-> ([ProgramName] -> ShowS)
-> Show ProgramName
forall a.
(Int -> a -> ShowS) -> (a -> String) -> ([a] -> ShowS) -> Show a
showList :: [ProgramName] -> ShowS
$cshowList :: [ProgramName] -> ShowS
show :: ProgramName -> String
$cshow :: ProgramName -> String
showsPrec :: Int -> ProgramName -> ShowS
$cshowsPrec :: Int -> ProgramName -> ShowS
Show)

instance IsString ProgramName where
  fromString :: String -> ProgramName
fromString = String -> ProgramName
ProgramName

formatHpackError :: ProgramName -> HpackError -> String
formatHpackError :: ProgramName -> HpackError -> String
formatHpackError (ProgramName String
progName) = \ case
  HpackVersionNotSupported String
file Version
wanted Version
supported ->
    String
"The file " String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
file String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" requires version " String -> ShowS
forall a. [a] -> [a] -> [a]
++ Version -> String
showVersion Version
wanted String -> ShowS
forall a. [a] -> [a] -> [a]
++
    String
" of the Hpack package specification, however this version of " String -> ShowS
forall a. [a] -> [a] -> [a]
++
    String
progName String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" only supports versions up to " String -> ShowS
forall a. [a] -> [a] -> [a]
++ Version -> String
showVersion Version
supported String -> ShowS
forall a. [a] -> [a] -> [a]
++
    String
". Upgrading to the latest version of " String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
progName String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" may resolve this issue."
  DefaultsFileNotFound String
file -> String
"Invalid value for \"defaults\"! File " String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
file String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" does not exist!"
  DefaultsDownloadFailed String
url Status
status -> String
"Error while downloading " String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
url String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" (" String -> ShowS
forall a. [a] -> [a] -> [a]
++ Status -> String
formatStatus Status
status String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
")"
  CycleInDefaults [String]
files -> String
"cycle in defaults (" String -> ShowS
forall a. [a] -> [a] -> [a]
++ String -> [String] -> String
forall a. [a] -> [[a]] -> [a]
intercalate String
" -> " [String]
files String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
")"
  ParseError String
err -> String
err
  DecodeValueError String
file String
err -> String
file String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
": " String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
err

formatStatus :: Status -> String
formatStatus :: Status -> String
formatStatus (Status Int
code ByteString
message) = Int -> String
forall a. Show a => a -> String
show Int
code String -> ShowS
forall a. [a] -> [a] -> [a]
++ String
" " String -> ShowS
forall a. [a] -> [a] -> [a]
++ ByteString -> String
B.unpack ByteString
message