dear-imgui.hs/generator/DearImGui/Generator/Parser.hs
Alexander Bondarenko dc11fad07f
Update to 1.87 (#125)
2022-02-13 00:26:39 +03:00

448 lines
14 KiB
Haskell

{-# LANGUAGE BlockArguments #-}
{-# LANGUAGE DerivingStrategies #-}
{-# LANGUAGE DuplicateRecordFields #-}
{-# LANGUAGE FlexibleContexts #-}
{-# LANGUAGE LambdaCase #-}
{-# LANGUAGE NamedFieldPuns #-}
{-# LANGUAGE OverloadedStrings #-}
{-# LANGUAGE RecordWildCards #-}
{-# LANGUAGE ScopedTypeVariables #-}
{-# LANGUAGE TemplateHaskellQuotes #-}
{-# LANGUAGE TypeApplications #-}
{-# LANGUAGE ViewPatterns #-}
module DearImGui.Generator.Parser
( CustomParseError(..)
, headers
)
where
-- base
import Control.Applicative
( (<|>), many, optional, some )
import Control.Monad
( void )
import Data.Bits
( Bits(shiftL) )
import Data.Char
( isSpace, toLower )
import Data.Either
( partitionEithers )
import Data.Functor
( ($>) )
import Data.Int
( Int64 )
import Data.Maybe
( catMaybes, fromMaybe )
import Foreign.C.Types
( CInt )
-- template-haskell
import qualified Language.Haskell.TH as TH
( Name )
-- megaparsec
import Text.Megaparsec
( MonadParsec(..), ShowErrorComponent(..)
, (<?>), anySingle, customFailure, single
)
-- parser-combinators
import Control.Applicative.Combinators
( manyTill, option, sepBy1, skipManyTill )
-- scientific
import Data.Scientific
( floatingOrInteger, toBoundedInteger )
-- text
import Data.Text
( Text )
import qualified Data.Text as Text
( all, any, breakOn, drop, dropWhile, dropWhileEnd
, length, stripPrefix, unlines, unpack
)
-- transformers
import Control.Monad.Trans.State.Strict
( StateT(..)
, get, modify'
)
-- unordered-containers
import Data.HashMap.Strict
( HashMap )
import qualified Data.HashMap.Strict as HashMap
( fromList, insert, lookup )
-- dear-imgui-generator
import DearImGui.Generator.Tokeniser
( Tok(..) )
import DearImGui.Generator.Types
( Comment(..), Enumeration(..), Headers(..) )
--------------------------------------------------------------------------------
-- Parse error type.
data CustomParseError
= Couldn'tLookupEnumValues
{ enumName :: !Text
, problems :: ![Text]
}
| MissingForwardDeclaration
{ enumName :: !Text }
| UnexpectedSection
{ sectionName :: !Text
, problem :: ![Text]
}
deriving stock ( Show, Eq, Ord )
instance ShowErrorComponent CustomParseError where
showErrorComponent ( Couldn'tLookupEnumValues { enumName, problems } ) = Text.unpack $
"Couldn't lookup the following values in enum " <> enumName <> ":\n"
<> Text.unlines ( map ( " - " <> ) problems )
showErrorComponent ( MissingForwardDeclaration { enumName } ) = Text.unpack $
"Missing forward declaration for enum named " <> enumName
showErrorComponent ( UnexpectedSection { sectionName, problem } ) = Text.unpack $
"Unexpected section name.\n\
\Expected: " <> sectionName <> "\n\
\ Actual: " <> Text.unlines ( map ( " " <> ) problem )
--------------------------------------------------------------------------------
-- Parsing headers.
headers :: MonadParsec CustomParseError [Tok] m => m ( Headers () )
headers = do
_ <- skipManyTill anySingle ( namedSection "Header mess" )
_ <- skipManyTill anySingle ( namedSection "Forward declarations" )
( _structNames, enumNamesAndTypes ) <- forwardDeclarations
_ <- skipManyTill anySingle ( namedSection "Dear ImGui end-user API functions" )
_ <- skipManyTill anySingle ( namedSection "Flags & Enumerations" )
( _defines, basicEnums ) <- partitionEithers <$>
manyTill
( ( Left <$> try ignoreDefine )
<|> ( Right <$> enumeration enumNamesAndTypes )
)
( namedSection "Helpers: Memory allocations macros, ImVector<>" )
_ <- skipManyTill anySingle ( namedSection "ImGuiStyle" )
_ <- skipManyTill anySingle ( namedSection "ImGuiIO" )
_ <- skipManyTill anySingle ( namedSection "Misc data structures" )
_ <- skipManyTill anySingle ( namedSection "Helpers (ImGuiOnceUponAFrame, ImGuiTextFilter, ImGuiTextBuffer, ImGuiStorage, ImGuiListClipper, ImColor)" )
_ <- skipManyTill anySingle ( namedSection "Drawing API (ImDrawCmd, ImDrawIdx, ImDrawVert, ImDrawChannel, ImDrawListSplitter, ImDrawListFlags, ImDrawList, ImDrawData)" )
skipManyTill anySingle ( try . lookAhead $ many comment *> keyword "enum" )
drawingEnums <- many ( enumeration enumNamesAndTypes )
_ <- skipManyTill anySingle ( namedSection "Font API (ImFontConfig, ImFontGlyph, ImFontAtlasFlags, ImFontAtlas, ImFontGlyphRangesBuilder, ImFont)" )
skipManyTill anySingle ( try . lookAhead $ many comment *> keyword "enum" )
fontEnums <- many ( enumeration enumNamesAndTypes )
_ <- skipManyTill anySingle ( namedSection "Viewports" )
_ <- skipManyTill anySingle ( namedSection "Platform Dependent Interfaces" ) -- XXX: since 1.87
_ <- skipManyTill anySingle ( namedSection "Obsolete functions and types" )
let
enums :: [ Enumeration () ]
enums = basicEnums <> drawingEnums <> fontEnums
pure ( Headers { enums } )
--------------------------------------------------------------------------------
-- Parsing forward declarations.
forwardDeclarations
:: MonadParsec CustomParseError [Tok] m
=> m ( HashMap Text Comment, HashMap Text ( TH.Name, Comment ) )
forwardDeclarations = do
_ <- many comment
structs <- many do
keyword "struct"
structName <- identifier
reservedSymbol ';'
doc <- comment
pure ( structName, doc )
_ <- many comment
enums <- many do
keyword "typedef"
ty <- cTypeName
enumName <- identifier
reservedSymbol ';'
doc <- commentText <$> comment
pure ( enumName, ( ty, CommentText <$> Text.drop 2 . snd $ Text.breakOn "//" doc ) )
-- Stopping after simple structs and enums for now.
pure ( HashMap.fromList structs, HashMap.fromList enums )
cTypeName :: MonadParsec e [Tok] m => m TH.Name
cTypeName = keyword "int" $> ''CInt
--------------------------------------------------------------------------------
-- Parsing enumerations.
data EnumState = EnumState
{ enumValues :: HashMap Text Integer
, currEnumTag :: Integer
, enumSize :: Integer
, hasExplicitCount :: Bool
}
enumeration :: MonadParsec CustomParseError [Tok] m => HashMap Text ( TH.Name, Comment ) -> m ( Enumeration () )
enumeration enumNamesAndTypes = do
inlineDocs <- try do
inlineDocs <- many comment
keyword "enum"
pure inlineDocs
fullEnumName <- identifier
let
enumName :: Text
enumName = Text.dropWhileEnd ( == '_' ) fullEnumName
enumTypeName :: ()
enumTypeName = ()
( underlyingType, forwardDoc ) <- case HashMap.lookup enumName enumNamesAndTypes of
Just res -> pure res
Nothing -> customFailure ( MissingForwardDeclaration { enumName } )
let
docs :: [Comment]
docs = forwardDoc : CommentText "" : inlineDocs
reservedSymbol '{'
( patterns, EnumState { enumSize, hasExplicitCount } ) <-
( `runStateT` EnumState { enumValues = mempty, currEnumTag = 0, enumSize = 0, hasExplicitCount = False } ) $
catMaybes
<$> many
( some ignoredPatternContent $> Nothing
<|> enumerationPattern fullEnumName
)
reservedSymbol '}'
reservedSymbol ';'
pure ( Enumeration { .. } )
ignoredPatternContent :: MonadParsec e [Tok] m => m ()
ignoredPatternContent = void ( try comment ) <|> cppConditional
enumerationPattern
:: MonadParsec CustomParseError [ Tok ] m
=> Text
-> StateT EnumState m ( Maybe ( Text, Integer, Comment ) )
enumerationPattern enumName = do
mbPatNameVal <- patternNameAndValue enumName
_ <- optional $ reservedSymbol ','
comm <- fromMaybe ( CommentText "" ) <$> optional comment
pure $
case mbPatNameVal of
Nothing -> Nothing
Just ( patName, patValue ) -> Just ( patName, patValue, comm )
patternNameAndValue
:: forall m
. MonadParsec CustomParseError [ Tok ] m
=> Text
-> StateT EnumState m ( Maybe ( Text, Integer ) )
patternNameAndValue enumName =
try do
sz <- count
modify' ( \ ( EnumState {..} ) -> EnumState { enumSize = sz, hasExplicitCount = True, .. } )
pure Nothing
<|> do
pat@( _, val ) <- value
modify' ( \ ( EnumState {..} ) -> EnumState { enumSize = enumSize + 1, currEnumTag = val + 1, .. } )
pure ( Just pat )
where
count :: StateT EnumState m Integer
count = do
let idName = enumName <> "COUNT"
_ <- single ( Identifier idName )
mbVal <- optional do
_ <- reservedSymbol '='
EnumState{enumValues} <- get
integerExpression enumValues
countVal <- case mbVal of
Nothing -> currEnumTag <$> get
Just ct -> pure ct
modify' ( \ st -> st { enumValues = HashMap.insert idName countVal ( enumValues st ) } )
pure countVal
value :: StateT EnumState m ( Text, Integer )
value = do
name <- identifier
val <- patternRHS
modify' ( \ st -> st { enumValues = HashMap.insert name val ( enumValues st ) } )
pure ( name, val )
patternRHS :: StateT EnumState m Integer
patternRHS =
( do
reservedSymbol '='
EnumState{enumValues} <- get
try disjunction <|> try (integerExpression enumValues)
)
<|> ( currEnumTag <$> get )
disjunction :: StateT EnumState m Integer
disjunction = do
initial <- identifier <* symbol "|"
( rest :: [Text] ) <- identifier `sepBy1` symbol "|"
let summands = initial : rest
valsMap <- enumValues <$> get
let
res :: Either [ Text ] Integer
res = foldr
( \ summand errsOrVal -> case HashMap.lookup summand valsMap of
Nothing -> case errsOrVal of { Right _ -> Left [ summand ]; Left errs -> Left ( summand : errs ) }
Just v -> case errsOrVal of { Right v' -> Right ( v + v' ); Left errs -> Left errs }
)
( Right 0 )
summands
case res of
Left problems -> customFailure ( Couldn'tLookupEnumValues { enumName, problems } )
Right v -> pure v
--------------------------------------------------------------------------------
-- Simple token parsers.
comment :: MonadParsec e [ Tok ] m => m Comment
comment = CommentText <$>
token ( \ case { Comment comm -> Just comm; _ -> Nothing } ) mempty
<?> "comment"
keyword :: MonadParsec e [ Tok ] m => Text -> m ()
keyword kw = token ( \ case { Keyword kw' | kw == kw' -> Just (); _ -> Nothing } ) mempty
<?> ( Text.unpack kw <> " (keyword)" )
identifier :: MonadParsec e [ Tok ] m => m Text
identifier = token ( \ case { Identifier i -> Just i; _ -> Nothing } ) mempty
<?> "identifier"
{-
prefixedIdentifier :: MonadParsec e [ Tok ] m => Text -> m Text
prefixedIdentifier prefix =
token
( \ case
{ Identifier i -> Text.dropWhile ( == '_' ) <$> Text.stripPrefix prefix i
; _ -> Nothing
}
) mempty
-}
reservedSymbol :: MonadParsec e [ Tok ] m => Char -> m ()
reservedSymbol s = token ( \ case { ReservedSymbol s' | s == s' -> Just (); _ -> Nothing } ) mempty
<?> ( [s] <> " (reserved symbol)" )
symbol :: MonadParsec e [ Tok ] m => Text -> m ()
symbol s = token ( \ case { Symbolic s' | s == s' -> Just (); _ -> Nothing } ) mempty
<?> ( Text.unpack s <> " (symbol)" )
integerExpression :: MonadParsec e [ Tok ] m => HashMap Text Integer -> m Integer
integerExpression enums = try integerPower <|> try integerAdd <|> try integerSub <|> integer
where
integerPower :: MonadParsec e [ Tok ] m => m Integer
integerPower = do
a <- integer
_ <- symbol "<<"
i <- integer
pure ( a `shiftL` fromIntegral i )
integerAdd :: MonadParsec e [ Tok ] m => m Integer
integerAdd = do
a <- integer
_ <- symbol "+"
i <- integer
pure ( a + i )
integerSub :: MonadParsec e [ Tok ] m => m Integer
integerSub = do
a <- integer
_ <- symbol "-"
i <- integer
pure ( a - i )
integer :: forall e m. MonadParsec e [ Tok ] m => m Integer
integer =
option id mkSign <*>
token
( \case
Number i suff
| Just _ <- toBoundedInteger @Int64 i
, Right i' <- floatingOrInteger @Float @Integer i
, not ( Text.any ( (== 'f' ) . toLower ) suff )
->
Just i'
Identifier name ->
HashMap.lookup name enums
_ ->
Nothing
)
mempty
<?> "integer"
where
mkSign :: m ( Integer -> Integer )
mkSign = ( symbol "+" $> id ) <|> ( symbol "-" $> negate )
section :: MonadParsec e [ Tok ] m => m [Text]
section =
do
sectionText <- try do
separator
token
( \ case
{ Comment txt -> fmap ( Text.dropWhile isSpace )
. Text.stripPrefix "[SECTION]"
. Text.dropWhile isSpace
$ txt
; _ -> Nothing
}
) mempty
rest <- endOfSectionHeader
pure ( sectionText : filter ( not . Text.all ( \ c -> c == '-' || isSpace c ) ) rest )
<?> "section"
separator :: MonadParsec e [ Tok ] m => m ()
separator = token
( \ case
{ Comment hyphens | Text.length hyphens > 10 && Text.all ( == '-') hyphens -> Just ()
; _ -> Nothing
}
) mempty
<?> "separator"
endOfSectionHeader :: MonadParsec e [ Tok ] m => m [Text]
endOfSectionHeader = try ( (:) <$> ( commentText <$> comment ) <*> endOfSectionHeader )
<|> ( separator $> [] )
namedSection :: MonadParsec CustomParseError [ Tok ] m => Text -> m ()
namedSection sectionName =
do
sectionTexts <- section
case sectionTexts of
sectionText : _
| Just _ <- Text.stripPrefix sectionName sectionText
-> pure ()
_ -> customFailure ( UnexpectedSection { sectionName, problem = sectionTexts } )
<?> ( "section named " <> Text.unpack sectionName )
cppDirective :: MonadParsec e [Tok] m => ( Text -> Maybe a ) -> m a
cppDirective f = token ( \case { BeginCPP a -> f a; _ -> Nothing } ) mempty
cppConditional :: MonadParsec e [Tok] m => m ()
cppConditional = do
void $ cppDirective ( \case { "ifdef" -> Just True; "ifndef" -> Just False; _ -> Nothing } )
-- assumes no nesting
void $ skipManyTill anySingle ( cppDirective ( \case { "endif" -> Just (); _ -> Nothing } ) )
void $ skipManyTill anySingle ( single EndCPPLine )
ignoreDefine :: MonadParsec e [Tok] m => m ()
ignoreDefine = do
void $ many comment
void $ cppDirective ( \case { "define" -> Just (); _ -> Nothing } )
void $ skipManyTill anySingle ( single EndCPPLine )