    {-# LANGUAGE DeriveGeneric #-}
    {-# LANGUAGE GADTs #-}
    {-# LANGUAGE StandaloneDeriving #-}

    module GHC.Driver.Errors.Types (
        GhcMessage(..)
      , GhcMessageOpts(..)
      , DriverMessage(..)
      , DriverMessageOpts(..)
      , DriverMessages, PsMessage(PsHeaderMessage)
      , WarningMessages
      , ErrorMessages
      , WarnMsg
      -- * Constructors
      , ghcUnknownMessage
      -- * Utility functions
      , hoistTcRnMessage
      , hoistDsMessage
      , checkBuildingCabalPackage
      ) where

    import GHC.Prelude

    import Data.Bifunctor
    import Data.Typeable

    import GHC.Driver.DynFlags (DynFlags, PackageArg, gopt)
    import GHC.Driver.Flags (GeneralFlag (Opt_BuildingCabalPackage))
    import GHC.Types.Error
    import GHC.Unit.Module
    import GHC.Unit.State

    import GHC.Parser.Errors.Types ( PsMessage(PsHeaderMessage) )
    import GHC.HsToCore.Errors.Types ( DsMessage )
    import GHC.Hs.Extension          (GhcTc)

    import Language.Haskell.Syntax.Decls (RuleDecl)
    import qualified GHC.LanguageExtensions as LangExt

    import GHC.Generics ( Generic )

    import GHC.Tc.Errors.Types
    import GHC.Iface.Errors.Types

    -- | A collection of warning messages.
    -- /INVARIANT/: Each 'GhcMessage' in the collection should have 'SevWarning' severity.
    type WarningMessages = Messages GhcMessage

    -- | A collection of error messages.
    -- /INVARIANT/: Each 'GhcMessage' in the collection should have 'SevError' severity.
    type ErrorMessages   = Messages GhcMessage

    -- | A single warning message.
    -- /INVARIANT/: It must have 'SevWarning' severity.
    type WarnMsg         = MsgEnvelope GhcMessage

    {- Note [GhcMessage]
    ~~~~~~~~~~~~~~~~~~~~

    We might need to report diagnostics (error and/or warnings) to the users. The
    'GhcMessage' type is the root of the diagnostic hierarchy.

    It's useful to have a separate type constructor for the different stages of
    the compilation pipeline. This is not just helpful for tools, as it gives a
    clear indication on where the error occurred exactly. Furthermore it increases
    the modularity amongst the different components of GHC (i.e. to avoid having
    "everything depend on everything else") and allows us to write separate
    functions that renders the different kind of messages.

    -}

    -- | The umbrella type that encompasses all the different messages that GHC
    -- might output during the different compilation stages. See
    -- Note [GhcMessage].
    data GhcMessage where
      -- | A message from the parsing phase.
      GhcPsMessage      :: PsMessage -> GhcMessage
      -- | A message from typecheck/renaming phase.
      GhcTcRnMessage    :: TcRnMessage -> GhcMessage
      -- | A message from the desugaring (HsToCore) phase.
      GhcDsMessage      :: DsMessage -> GhcMessage
      -- | A message from the driver.
      GhcDriverMessage  :: DriverMessage -> GhcMessage

      -- | An \"escape\" hatch which can be used when we don't know the source of
      -- the message or if the message is not one of the typed ones. The
      -- 'Diagnostic' and 'Typeable' constraints ensure that if we /know/, at
      -- pattern-matching time, the originating type, we can attempt a cast and
      -- access the fully-structured error. This would be the case for a GHC
      -- plugin that offers a domain-specific error type but that doesn't want to
      -- place the burden on IDEs/application code to \"know\" it. The
      -- 'Diagnostic' constraint ensures that worst case scenario we can still
      -- render this into something which can be eventually converted into a
      -- 'DecoratedSDoc'.
      GhcUnknownMessage :: (UnknownDiagnostic (DiagnosticOpts GhcMessage)) -> GhcMessage

      deriving (forall x. GhcMessage -> Rep GhcMessage x)
    -> (forall x. Rep GhcMessage x -> GhcMessage) -> Generic GhcMessage
    forall x. Rep GhcMessage x -> GhcMessage
    forall x. GhcMessage -> Rep GhcMessage x
    forall a.
    (forall x. a -> Rep a x) -> (forall x. Rep a x -> a) -> Generic a
    $cfrom :: forall x. GhcMessage -> Rep GhcMessage x
    from :: forall x. GhcMessage -> Rep GhcMessage x
    $cto :: forall x. Rep GhcMessage x -> GhcMessage
    to :: forall x. Rep GhcMessage x -> GhcMessage
    Generic

    data GhcMessageOpts = GhcMessageOpts { GhcMessageOpts -> DiagnosticOpts PsMessage
    psMessageOpts :: DiagnosticOpts PsMessage
                                         , GhcMessageOpts -> DiagnosticOpts TcRnMessage
    tcMessageOpts :: DiagnosticOpts TcRnMessage
                                         , GhcMessageOpts -> DiagnosticOpts DsMessage
    dsMessageOpts :: DiagnosticOpts DsMessage
                                         , GhcMessageOpts -> DiagnosticOpts DriverMessage
    driverMessageOpts :: DiagnosticOpts DriverMessage
                                         }

    -- | Creates a new 'GhcMessage' out of any diagnostic. This function is also
    -- provided to ease the integration of #18516 by allowing diagnostics to be
    -- wrapped into the general (but structured) 'GhcMessage' type, so that the
    -- conversion can happen gradually. This function should not be needed within
    -- GHC, as it would typically be used by plugin or library authors (see
    -- comment for the 'GhcUnknownMessage' type constructor)
    ghcUnknownMessage :: (DiagnosticOpts a ~ NoDiagnosticOpts, Diagnostic a, Typeable a) => a -> GhcMessage
    ghcUnknownMessage :: forall a.
    (DiagnosticOpts a ~ NoDiagnosticOpts, Diagnostic a, Typeable a) =>
    a -> GhcMessage
    ghcUnknownMessage = UnknownDiagnostic (DiagnosticOpts GhcMessage) -> GhcMessage
    GhcUnknownMessage (UnknownDiagnostic (DiagnosticOpts GhcMessage) -> GhcMessage)
    -> (a -> UnknownDiagnostic (DiagnosticOpts GhcMessage))
    -> a
    -> GhcMessage
    forall b c a. (b -> c) -> (a -> b) -> a -> c
    . a -> UnknownDiagnostic (DiagnosticOpts GhcMessage)
    forall a b.
    (Diagnostic a, Typeable a, DiagnosticOpts a ~ NoDiagnosticOpts) =>
    a -> UnknownDiagnostic b
    mkSimpleUnknownDiagnostic

    -- | Abstracts away the frequent pattern where we are calling 'ioMsgMaybe' on
    -- the result of 'IO (Messages TcRnMessage, a)'.
    hoistTcRnMessage :: Monad m => m (Messages TcRnMessage, a) -> m (Messages GhcMessage, a)
    hoistTcRnMessage :: forall (m :: * -> *) a.
    Monad m =>
    m (Messages TcRnMessage, a) -> m (Messages GhcMessage, a)
    hoistTcRnMessage = ((Messages TcRnMessage, a) -> (Messages GhcMessage, a))
    -> m (Messages TcRnMessage, a) -> m (Messages GhcMessage, a)
    forall a b. (a -> b) -> m a -> m b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap ((Messages TcRnMessage -> Messages GhcMessage)
    -> (Messages TcRnMessage, a) -> (Messages GhcMessage, a)
    forall a b c. (a -> b) -> (a, c) -> (b, c)
    forall (p :: * -> * -> *) a b c.
    Bifunctor p =>
    (a -> b) -> p a c -> p b c
    first ((TcRnMessage -> GhcMessage)
    -> Messages TcRnMessage -> Messages GhcMessage
    forall a b. (a -> b) -> Messages a -> Messages b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap TcRnMessage -> GhcMessage
    GhcTcRnMessage))

    -- | Abstracts away the frequent pattern where we are calling 'ioMsgMaybe' on
    -- the result of 'IO (Messages DsMessage, a)'.
    hoistDsMessage :: Monad m => m (Messages DsMessage, a) -> m (Messages GhcMessage, a)
    hoistDsMessage :: forall (m :: * -> *) a.
    Monad m =>
    m (Messages DsMessage, a) -> m (Messages GhcMessage, a)
    hoistDsMessage = ((Messages DsMessage, a) -> (Messages GhcMessage, a))
    -> m (Messages DsMessage, a) -> m (Messages GhcMessage, a)
    forall a b. (a -> b) -> m a -> m b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap ((Messages DsMessage -> Messages GhcMessage)
    -> (Messages DsMessage, a) -> (Messages GhcMessage, a)
    forall a b c. (a -> b) -> (a, c) -> (b, c)
    forall (p :: * -> * -> *) a b c.
    Bifunctor p =>
    (a -> b) -> p a c -> p b c
    first ((DsMessage -> GhcMessage)
    -> Messages DsMessage -> Messages GhcMessage
    forall a b. (a -> b) -> Messages a -> Messages b
    forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
    fmap DsMessage -> GhcMessage
    GhcDsMessage))

    -- | A collection of driver messages
    type DriverMessages = Messages DriverMessage

    -- | A message from the driver.
    data DriverMessage where
      -- | Simply wraps a generic 'Diagnostic' message @a@.
      DriverUnknownMessage :: UnknownDiagnostic (DiagnosticOpts DriverMessage) -> DriverMessage

      -- | A parse error in parsing a Haskell file header during dependency
      -- analysis
      DriverPsHeaderMessage :: !PsMessage -> DriverMessage

      {-| DriverMissingHomeModules is a warning (controlled with -Wmissing-home-modules) that
          arises when running GHC in --make mode when some modules needed for compilation
          are not included on the command line. For example, if A imports B, `ghc --make
          A.hs` will cause this warning, while `ghc --make A.hs B.hs` will not.

          Useful for cabal to ensure GHC won't pick up modules listed neither in
          'exposed-modules' nor in 'other-modules'.

          Test case: warnings/should_compile/MissingMod

      -}
      DriverMissingHomeModules :: UnitId -> [ModuleName] -> !BuildingCabalPackage -> DriverMessage

      {-| DriverUnknown is a warning that arises when a user tries to
          reexport a module which isn't part of that unit.
      -}
      DriverUnknownReexportedModules :: UnitId -> [ModuleName] -> DriverMessage

      {-| DriverUnknownHiddenModules is a warning that arises when a user tries to
          hide a module which isn't part of that unit.
      -}
      DriverUnknownHiddenModules :: UnitId -> [ModuleName] -> DriverMessage

      {-| DriverUnusedPackages occurs when when package is requested on command line,
          but was never needed during compilation. Activated by -Wunused-packages.

         Test cases: warnings/should_compile/UnusedPackages
      -}
      DriverUnusedPackages :: [(UnitId, PackageName, Version, PackageArg)] -> DriverMessage

      {-| DriverUnnecessarySourceImports (controlled with -Wunused-imports) occurs if there
          are {-# SOURCE #-} imports which are not necessary. See 'warnUnnecessarySourceImports'
          in 'GHC.Driver.Make'.

         Test cases: warnings/should_compile/T10637
      -}
      DriverUnnecessarySourceImports :: !ModuleName -> DriverMessage

      {-| DriverDuplicatedModuleDeclaration occurs if a module 'A' is declared in
           multiple files.

         Test cases: None.
      -}
      DriverDuplicatedModuleDeclaration :: !Module -> [FilePath] -> DriverMessage

      {-| DriverModuleNotFound occurs if a module 'A' can't be found.

         Test cases: None.
      -}
      DriverModuleNotFound :: !ModuleName -> DriverMessage

      {-| DriverFileModuleNameMismatch occurs if a module 'A' is defined in a file with a different name.
          The first field is the name written in the source code; the second argument is the name extracted
          from the filename.

         Test cases: module/mod178, /driver/bug1677
      -}
      DriverFileModuleNameMismatch :: !ModuleName -> !ModuleName -> DriverMessage

      {-| DriverUnexpectedSignature occurs when GHC encounters a module 'A' that imports a signature
          file which is neither in the 'signatures' section of a '.cabal' file nor in any package in
          the home modules.

          Example:

          -- MyStr.hsig is defined, but not added to 'signatures' in the '.cabal' file.
          signature MyStr where
              data Str

          -- A.hs, which tries to import the signature.
          module A where
          import MyStr

         Test cases: driver/T12955
      -}
      DriverUnexpectedSignature :: !ModuleName -> !BuildingCabalPackage -> GenInstantiations UnitId -> DriverMessage

      {-| DriverFileNotFound occurs when the input file (e.g. given on the command line) can't be found.

         Test cases: None.
      -}
      DriverFileNotFound :: !FilePath -> DriverMessage

      {-| DriverStaticPointersNotSupported occurs when the 'StaticPointers' extension is used
           in an interactive GHCi context.

         Test cases: ghci/scripts/StaticPtr
      -}
      DriverStaticPointersNotSupported :: DriverMessage

      {-| DriverBackpackModuleNotFound occurs when Backpack can't find a particular module
          during its dependency analysis.

         Test cases: -
      -}
      DriverBackpackModuleNotFound :: !ModuleName -> DriverMessage

      {-| DriverUserDefinedRuleIgnored is a warning that occurs when user-defined rules
          are ignored. This typically happens when Safe Haskell.

         Test cases:

           tests/safeHaskell/safeInfered/UnsafeWarn05
           tests/safeHaskell/safeInfered/UnsafeWarn06
           tests/safeHaskell/safeInfered/UnsafeWarn07
           tests/safeHaskell/safeInfered/UnsafeInfered11
           tests/safeHaskell/safeLanguage/SafeLang03
      -}
      DriverUserDefinedRuleIgnored :: !(RuleDecl GhcTc) -> DriverMessage

      {-| DriverMixedSafetyImport is an error that occurs when a module is imported
          both as safe and unsafe.

        Test cases:

          tests/safeHaskell/safeInfered/Mixed03
          tests/safeHaskell/safeInfered/Mixed02

      -}
      DriverMixedSafetyImport :: !ModuleName -> DriverMessage

      {-| DriverCannotLoadInterfaceFile is an error that occurs when we cannot load the interface
          file for a particular module. This can happen for example in the context of Safe Haskell,
          when we have to load a module to check if it can be safely imported.

        Test cases: None.

      -}
      DriverCannotLoadInterfaceFile :: !Module -> DriverMessage

      {-| DriverInferredSafeImport is a warning (controlled by the Opt_WarnSafe flag)
          that occurs when a module is inferred safe.

        Test cases: None.

      -}
      DriverInferredSafeModule :: !Module -> DriverMessage

      {-| DriverMarkedTrustworthyButInferredSafe is a warning (controlled by the Opt_WarnTrustworthySafe flag)
          that occurs when a module is marked trustworthy in SafeHaskell but it has been inferred safe.

        Test cases:
          tests/safeHaskell/safeInfered/TrustworthySafe02
          tests/safeHaskell/safeInfered/TrustworthySafe03

      -}
      DriverMarkedTrustworthyButInferredSafe :: !Module -> DriverMessage

      {-| DriverInferredSafeImport is a warning (controlled by the Opt_WarnInferredSafeImports flag)
          that occurs when a safe-inferred module is imported from a safe module.

        Test cases: None.

      -}
      DriverInferredSafeImport :: !Module -> DriverMessage

      {-| DriverCannotImportUnsafeModule is an error that occurs when an usafe module
          is being imported from a safe one.

        Test cases: None.

      -}
      DriverCannotImportUnsafeModule :: !Module -> DriverMessage

      {-| DriverMissingSafeHaskellMode is a warning (controlled by the Opt_WarnMissingSafeHaskellMode flag)
          that occurs when a module is using SafeHaskell features but SafeHaskell mode is not enabled.

        Test cases: None.

      -}
      DriverMissingSafeHaskellMode :: !Module -> DriverMessage

      {-| DriverPackageNotTrusted is an error that occurs when a package is required to be trusted
          but it isn't.

        Test cases:
          tests/safeHaskell/check/Check01
          tests/safeHaskell/check/Check08
          tests/safeHaskell/check/Check06
          tests/safeHaskell/check/pkg01/ImpSafeOnly09
          tests/safeHaskell/check/pkg01/ImpSafe03
          tests/safeHaskell/check/pkg01/ImpSafeOnly07
          tests/safeHaskell/check/pkg01/ImpSafeOnly08

      -}
      DriverPackageNotTrusted :: !UnitState -> !UnitId -> DriverMessage

      {-| DriverCannotImportFromUntrustedPackage is an error that occurs in the context of
          Safe Haskell when trying to import a module coming from an untrusted package.

        Test cases:
          tests/safeHaskell/check/Check09
          tests/safeHaskell/check/pkg01/ImpSafe01
          tests/safeHaskell/check/pkg01/ImpSafe04
          tests/safeHaskell/check/pkg01/ImpSafeOnly03
          tests/safeHaskell/check/pkg01/ImpSafeOnly05
          tests/safeHaskell/flags/SafeFlags17
          tests/safeHaskell/flags/SafeFlags22
          tests/safeHaskell/flags/SafeFlags23
          tests/safeHaskell/ghci/p11
          tests/safeHaskell/ghci/p12
          tests/safeHaskell/ghci/p17
          tests/safeHaskell/ghci/p3
          tests/safeHaskell/safeInfered/UnsafeInfered01
          tests/safeHaskell/safeInfered/UnsafeInfered02
          tests/safeHaskell/safeInfered/UnsafeInfered02
          tests/safeHaskell/safeInfered/UnsafeInfered03
          tests/safeHaskell/safeInfered/UnsafeInfered05
          tests/safeHaskell/safeInfered/UnsafeInfered06
          tests/safeHaskell/safeInfered/UnsafeInfered09
          tests/safeHaskell/safeInfered/UnsafeInfered10
          tests/safeHaskell/safeInfered/UnsafeInfered11
          tests/safeHaskell/safeInfered/UnsafeWarn01
          tests/safeHaskell/safeInfered/UnsafeWarn03
          tests/safeHaskell/safeInfered/UnsafeWarn04
          tests/safeHaskell/safeInfered/UnsafeWarn05
          tests/safeHaskell/unsafeLibs/BadImport01
          tests/safeHaskell/unsafeLibs/BadImport06
          tests/safeHaskell/unsafeLibs/BadImport07
          tests/safeHaskell/unsafeLibs/BadImport08
          tests/safeHaskell/unsafeLibs/BadImport09
          tests/safeHaskell/unsafeLibs/Dep05
          tests/safeHaskell/unsafeLibs/Dep06
          tests/safeHaskell/unsafeLibs/Dep07
          tests/safeHaskell/unsafeLibs/Dep08
          tests/safeHaskell/unsafeLibs/Dep09
          tests/safeHaskell/unsafeLibs/Dep10

      -}
      DriverCannotImportFromUntrustedPackage :: !UnitState -> !Module -> DriverMessage

      DriverRedirectedNoMain :: !ModuleName -> DriverMessage

      DriverHomePackagesNotClosed :: ![UnitId] -> DriverMessage

      DriverInterfaceError :: !IfaceMessage -> DriverMessage

      -- TODO: Add structure messages rather than a String
      DriverInconsistentDynFlags :: String -> DriverMessage

      DriverSafeHaskellIgnoredExtension :: !LangExt.Extension -> DriverMessage

      DriverPackageTrustIgnored :: DriverMessage

      DriverUnrecognisedFlag :: String -> DriverMessage

      DriverDeprecatedFlag :: String -> String -> DriverMessage

    deriving instance Generic DriverMessage

    data DriverMessageOpts =
      DriverMessageOpts { DriverMessageOpts -> DiagnosticOpts PsMessage
    psDiagnosticOpts :: DiagnosticOpts PsMessage
                        , DriverMessageOpts -> DiagnosticOpts IfaceMessage
    ifaceDiagnosticOpts :: DiagnosticOpts IfaceMessage }

    -- | Checks if we are building a cabal package by consulting the 'DynFlags'.
    checkBuildingCabalPackage :: DynFlags -> BuildingCabalPackage
    checkBuildingCabalPackage :: DynFlags -> BuildingCabalPackage
    checkBuildingCabalPackage DynFlags
    dflags =
      if GeneralFlag -> DynFlags -> Bool
    gopt GeneralFlag
    Opt_BuildingCabalPackage DynFlags
    dflags
         then BuildingCabalPackage
    YesBuildingCabalPackage
         else BuildingCabalPackage
    NoBuildingCabalPackage