{- -----------------------------------------------------------------------------
Copyright 2020 Kevin P. Barry

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
----------------------------------------------------------------------------- -}

-- Author: Kevin P. Barry [ta0kira@gmail.com]

{-# LANGUAGE FlexibleInstances #-}
{-# LANGUAGE TypeSynonymInstances #-}
-- Older versions of Text.Megaparsec are Unsafe. This makes sure that the
-- compiler catches imports into Safe sources when a newer version is used.
{-# LANGUAGE Unsafe #-}

module Parser.TextParser (
  module Text.Megaparsec,
  module Text.Megaparsec.Char,
  SourceContext,
  TextParser,
  getSourceContext,
  runTextParser,
) where

import Data.Char (isSpace)
import Data.List (dropWhileEnd)
import Text.Megaparsec
import Text.Megaparsec.Char
import qualified Data.Set as Set

import Base.CompilerError
import Base.CompilerMessage


type TextParser = Parsec CompilerMessage String

instance ErrorContextM TextParser where
  compilerErrorM :: forall a. String -> TextParser a
compilerErrorM = forall e s (m :: * -> *) a. MonadParsec e s m => e -> m a
customFailure forall b c a. (b -> c) -> (a -> b) -> a -> c
. String -> CompilerMessage
compilerMessage
  withContextM :: forall a. TextParser a -> String -> TextParser a
withContextM     TextParser a
x String
e = forall e s (m :: * -> *) a.
MonadParsec e s m =>
(ParseError s e -> ParseError s e) -> m a -> m a
region (forall e' e s.
Ord e' =>
(e -> e') -> ParseError s e -> ParseError s e'
mapParseError (String -> CompilerMessage -> CompilerMessage
pushErrorScope String
e) forall b c a. (b -> c) -> (a -> b) -> a -> c
. ParseError String CompilerMessage
-> ParseError String CompilerMessage
promoteError) TextParser a
x
  summarizeErrorsM :: forall a. TextParser a -> String -> TextParser a
summarizeErrorsM TextParser a
x String
e = forall e s (m :: * -> *) a.
MonadParsec e s m =>
(ParseError s e -> ParseError s e) -> m a -> m a
region (forall e' e s.
Ord e' =>
(e -> e') -> ParseError s e -> ParseError s e'
mapParseError (String -> CompilerMessage -> CompilerMessage
pushErrorScope String
e) forall b c a. (b -> c) -> (a -> b) -> a -> c
. ParseError String CompilerMessage
-> ParseError String CompilerMessage
promoteError) TextParser a
x

instance ShowErrorComponent CompilerMessage where
  showErrorComponent :: CompilerMessage -> String
showErrorComponent = forall a. Show a => a -> String
show

runTextParser :: ErrorContextM m => TextParser a -> String -> String -> m a
runTextParser :: forall (m :: * -> *) a.
ErrorContextM m =>
TextParser a -> String -> String -> m a
runTextParser TextParser a
p String
n String
s = case forall e s a.
Parsec e s a -> String -> s -> Either (ParseErrorBundle s e) a
parse TextParser a
p String
n String
s of
                           Left ParseErrorBundle String CompilerMessage
e  -> forall (m :: * -> *) a. ErrorContextM m => String -> m a
compilerErrorM forall a b. (a -> b) -> a -> b
$ forall a. (a -> Bool) -> [a] -> [a]
dropWhileEnd Char -> Bool
isSpace forall a b. (a -> b) -> a -> b
$ forall s e.
(VisualStream s, TraversableStream s, ShowErrorComponent e) =>
ParseErrorBundle s e -> String
errorBundlePretty ParseErrorBundle String CompilerMessage
e
                           Right a
x -> forall (m :: * -> *) a. Monad m => a -> m a
return a
x

newtype SourceContext = SourceContext SourcePos deriving (SourceContext -> SourceContext -> Bool
forall a. (a -> a -> Bool) -> (a -> a -> Bool) -> Eq a
/= :: SourceContext -> SourceContext -> Bool
$c/= :: SourceContext -> SourceContext -> Bool
== :: SourceContext -> SourceContext -> Bool
$c== :: SourceContext -> SourceContext -> Bool
Eq,Eq SourceContext
SourceContext -> SourceContext -> Bool
SourceContext -> SourceContext -> Ordering
SourceContext -> SourceContext -> SourceContext
forall a.
Eq a
-> (a -> a -> Ordering)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> Bool)
-> (a -> a -> a)
-> (a -> a -> a)
-> Ord a
min :: SourceContext -> SourceContext -> SourceContext
$cmin :: SourceContext -> SourceContext -> SourceContext
max :: SourceContext -> SourceContext -> SourceContext
$cmax :: SourceContext -> SourceContext -> SourceContext
>= :: SourceContext -> SourceContext -> Bool
$c>= :: SourceContext -> SourceContext -> Bool
> :: SourceContext -> SourceContext -> Bool
$c> :: SourceContext -> SourceContext -> Bool
<= :: SourceContext -> SourceContext -> Bool
$c<= :: SourceContext -> SourceContext -> Bool
< :: SourceContext -> SourceContext -> Bool
$c< :: SourceContext -> SourceContext -> Bool
compare :: SourceContext -> SourceContext -> Ordering
$ccompare :: SourceContext -> SourceContext -> Ordering
Ord)

instance Show SourceContext where
  show :: SourceContext -> String
show (SourceContext (SourcePos String
f Pos
l Pos
c)) =
    String
"line " forall a. [a] -> [a] -> [a]
++ forall a. Show a => a -> String
show (Pos -> Int
unPos Pos
l) forall a. [a] -> [a] -> [a]
++ String
" column " forall a. [a] -> [a] -> [a]
++ forall a. Show a => a -> String
show (Pos -> Int
unPos Pos
c) forall a. [a] -> [a] -> [a]
++ String
" of " forall a. [a] -> [a] -> [a]
++ String
f

getSourceContext :: TextParser SourceContext
getSourceContext :: TextParser SourceContext
getSourceContext = forall (f :: * -> *) a b. Functor f => (a -> b) -> f a -> f b
fmap SourcePos -> SourceContext
SourceContext forall s e (m :: * -> *).
(TraversableStream s, MonadParsec e s m) =>
m SourcePos
getSourcePos

promoteError :: ParseError String CompilerMessage -> ParseError String CompilerMessage
promoteError :: ParseError String CompilerMessage
-> ParseError String CompilerMessage
promoteError e :: ParseError String CompilerMessage
e@(TrivialError Int
i Maybe (ErrorItem (Token String))
_ Set (ErrorItem (Token String))
_) = forall s e. Int -> Set (ErrorFancy e) -> ParseError s e
FancyError Int
i forall a b. (a -> b) -> a -> b
$ forall a. Ord a => [a] -> Set a
Set.fromList [forall e. e -> ErrorFancy e
ErrorCustom forall a b. (a -> b) -> a -> b
$ String -> CompilerMessage
compilerMessage forall a b. (a -> b) -> a -> b
$ forall s e.
(VisualStream s, ShowErrorComponent e) =>
ParseError s e -> String
parseErrorTextPretty ParseError String CompilerMessage
e]
promoteError ParseError String CompilerMessage
e = ParseError String CompilerMessage
e