--
-- Haddock - A Haskell Documentation Tool
--
-- (c) Simon Marlow 2002
--

module Main (main) where

import HaddockRename
import HaddockParse
import HaddockLex
import HaddockDB
import HaddockHtml
import HaddockTypes

import HsLexer hiding (Token)
import HsParser
import HsParseMonad
import HsSyn
import GetOpt
import System
import FiniteMap

--import Pretty

import List	( nub )
import Monad	( when )
import Char	( isSpace )
import IO
import IOExts

-----------------------------------------------------------------------------
-- Top-level stuff

main = do
  args <- getArgs
  case getOpt Permute options args of
    (flags, args, []    ) -> run flags args
    (_,     _,    errors) -> do sequence_ (map putStr errors)
				putStr usage

usage = usageInfo "usage: haddock [OPTION] file...\n" options

data Flag
  = Flag_Verbose
  | Flag_DocBook
  | Flag_Html
  | Flag_Heading String
  | Flag_SourceURL String
  deriving (Eq)

options =
  [ 
    Option ['t']  ["heading"]  (ReqArg Flag_Heading "HEADING")
	"page heading",
    Option ['v']  ["verbose"]  (NoArg Flag_Verbose)
	"be verbose",
    Option ['d']  ["docbook"]  (NoArg Flag_DocBook)
	"output in docbook (SGML)",
    Option ['h']  ["html"]     (NoArg Flag_Html)
	"output in HTML",
    Option ['s']  ["source"]   (ReqArg Flag_SourceURL "URL") 
	"base URL for links to source code"
  ]

saved_flags :: IORef [Flag]
saved_flags = unsafePerformIO (newIORef (error "no flags yet"))

run flags files = do
  seq stderr $ do
  writeIORef saved_flags flags
  parsed_mods <- sequence (map parse_file files)

  let ifaces = [ mkInterface module_map file parsed 
	       | (file,parsed) <- zip files parsed_mods ]

      mod_ifaces = [ (m,i) | (m,i,_,_) <- ifaces ]
      module_map = listToFM mod_ifaces

  let title = case [str | Flag_Heading str <- flags] of
		[] -> ""
		(t:ts) -> t

      source_url = case [str | Flag_SourceURL str <- flags] of
			[] -> Nothing
			(t:ts) -> Just t

  sequence [ reportMissingNames m ns_docs ns_decls 
	   | (m, _, ns_docs, ns_decls) <- ifaces ]

  when (Flag_DocBook `elem` flags) $
    putStr (ppDocBook mod_ifaces)

  when (Flag_Html `elem` flags) $
    ppHtml title source_url mod_ifaces


parse_file file = do
  bracket 
    (openFile file ReadMode)
    (\h -> hClose h)
    (\h -> do stuff <- hGetContents h 
	      case parse stuff (SrcLoc 1 1) 1 0 [] of
	        Ok state e -> return e
	        Failed err -> do hPutStrLn stderr (file ++ ':':err)
				 exitWith (ExitFailure 1)
    )

reportMissingNames m [] [] = return ()
reportMissingNames (Module m) ns_docs ns_decls =  do
  hPutStrLn stderr ("Warning: in module " ++ m ++ 
		  ", the following names could not be resolved:")
  let name_strings = nub (map show ns_decls ++ ns_docs)
  hPutStrLn stderr ("   " ++ concat (map (' ':) name_strings))

-----------------------------------------------------------------------------
-- Figuring out the definitions that are exported from a module

mkInterface :: ModuleMap -> FilePath -> HsModule
   -> (Module, 		-- the module name
       Interface,	-- its "interface"
       [String],	-- a list of names we couldn't resolve in the docs
       [HsQName]	-- a list of names we couldn't resolve in the decls
      )

mkInterface mod_map filename (HsModule mod exps imps decls maybe_doc)
  = (mod, Interface { 
	   iface_filename = filename,
	   iface_env = name_env,
	   iface_exports = renamed_export_list,
	   iface_orig_exports = orig_export_list,
	   iface_decls =  decl_map,
	   iface_portability = "portable",
	   iface_maintainer  = "libraries@haskell.org",
	   iface_stability   = "stable",
	   iface_name_docs   = doc_map,
	   iface_doc         = module_doc
	},
      missing_names_doc1 ++ missing_names_doc2,   
      missing_names1 ++ missing_names2 --ignore missing_names3 for now,
    )
  where
  (module_doc, missing_names_doc1) = 
    case maybe_doc of
	Nothing  -> (Nothing, [])
	Just doc -> (Just doc', ns)
	  where (doc',ns) = formatDocString (lookupForDoc import_env) doc

  locally_defined_names = collectNames decls

  qual_local_names   = map (Qual mod) locally_defined_names
  unqual_local_names = map UnQual     locally_defined_names

  local_env = listToFM (zip unqual_local_names qual_local_names ++
			zip qual_local_names   qual_local_names)
	 -- both qualified and unqualifed names are in scope for local things

  -- build the orig_env, which maps names to *original* names (so we can
  -- find the original declarations & docs for things).
  (ext_orig_envs, ext_import_envs) 
	= unzip (map (buildEnv mod_map mod exported_names) imps)
  orig_env   = foldr plusFM local_env ext_orig_envs  
  import_env = foldr plusFM local_env ext_import_envs  

  -- convert names in source code to original, fully qualified, names
  (orig_exports, missing_names1) 
	= runRnFM orig_env (mapMaybeM renameExportList exps)

  (orig_decls, missing_names2)
	= runRnFM orig_env (mapM renameDecl decls)

  orig_decl_map :: FiniteMap HsName HsDecl
  orig_decl_map = listToFM [ (n,d) | d <- orig_decls, n <- declBinders d ]

  -- gather up a list of entities that are exported (original names)
  exported_names = exportedNames mod mod_map orig_decls
			locally_defined_names orig_exports
			orig_decl_map

  final_decls = concat (map expandDecl orig_decls)

  -- match documentation to names, and resolve identifiers in the documentation
  local_docstrings :: [(HsName,DocString)]
  local_docstrings = collectDoc final_decls

  local_docs_formatted :: [(HsName,(Doc,[String]))]
  local_docs_formatted = 
      [ (n, formatDocString (lookupForDoc orig_env) doc) 
      | (n, doc) <- local_docstrings ]

  local_docs :: [(HsName,Doc)]		-- with *original* names
  local_docs = [ (n,doc) | (n,(doc,_)) <- local_docs_formatted ]

  -- collect the list of names which we couldn't resolve in the documentation
  missing_names_doc2 = concat [ ns | (n,(doc,ns)) <- local_docs_formatted ]

  -- get the documentation associated with entities exported from this module
  -- ToDo: we should really store the documentation in both orig and imported
  -- forms, like the export items.
  doc_map :: FiniteMap HsName Doc	-- with *imported* names
  doc_map = listToFM 
    [ (nameOfQName n, doc)
    | n <- exported_names,
      Just doc <- [lookupDoc mod_map mod local_docs import_env n] ]

  decl_map :: FiniteMap HsName HsDecl
  decl_map = listToFM [ (n,d) | d <- final_decls, n <- declBinders d ]

  -- make the "export items", which will be converted into docs later
  orig_export_list = mkExportItems mod_map mod orig_env
			decl_map final_decls orig_exports 

  -- rename names in the exported declarations to point to things that
  -- are closer, or maybe even exported by, the current module.
  (renamed_export_list, missing_names3)
     = runRnFM import_env (renameExportItems orig_export_list)

  name_env = listToFM [ (nameOfQName n, n) | n <- exported_names ]

-- -----------------------------------------------------------------------------
-- Find the documentation for a particular name, and rename the
-- original identifiers embedded in it to imported names.

lookupDoc :: ModuleMap -> Module -> [(HsName,Doc)]
	-> FiniteMap HsQName HsQName -> HsQName -> Maybe Doc
lookupDoc mod_map this_mod local_doc env name
  = case name of
	UnQual n -> Nothing
	Qual mod n
	  | mod == this_mod -> 
		fst (runRnFM env (mapMaybeM renameDoc (lookup n local_doc)))
		-- ToDo: report missing names
	  | otherwise       -> 
		case lookupFM mod_map mod of
		   Nothing -> Nothing
		   Just iface -> 
			fst (runRnFM env (mapMaybeM renameDoc
				     (lookupFM (iface_name_docs iface) n)))
		-- ToDo: report missing names

-- -----------------------------------------------------------------------------
-- Build the list of items that will become the documentation, from the
-- export list.  At the same time we rename *original* names in the declarations
-- to *imported* names.

mkExportItems :: ModuleMap -> Module
	-> FiniteMap HsQName HsQName	-- maps orig to imported names
	-> FiniteMap HsName HsDecl	-- maps local names to declarations
	-> [HsDecl]			-- decls in the current module
	-> Maybe [HsExportSpec]
	-> [ExportItem]
mkExportItems mod_map mod env decl_map decls Nothing
  = fullContentsOfThisModule decls env -- everything exported
mkExportItems mod_map mod env decl_map decls (Just specs)
  = concat (map lookupExport specs)
  where
    lookupExport (HsEVar x) 
	| Just decl <- findDecl x
	= let decl' | HsTypeSig loc ns ty <- decl
			= HsTypeSig loc [nameOfQName x] ty
		    | otherwise
		  	= decl
	  in
	  [ ExportDecl decl' ]
	  -- ToDo: cope with record selectors here
    lookupExport (HsEAbs t)
	| Just decl <- findDecl t
	= [ ExportDecl (restrictTo [] decl) ]
    lookupExport (HsEThingAll t)
	| Just decl <- findDecl t
	= [ ExportDecl decl ]
    lookupExport (HsEThingWith t cs)
	| Just decl <- findDecl t
	= [ ExportDecl (restrictTo (map nameOfQName cs) decl) ]
    lookupExport (HsEModuleContents m) = fullContentsOf m
    lookupExport (HsEGroup lev str)
	= [ ExportGroup lev "" doc ]
	where (doc, _names) = formatDocHeading (lookupForDoc env) str
	-- ToDo: report the unresolved names
    lookupExport _ = [] -- didn't find it?

    fullContentsOf m
	| m == mod  = fullContentsOfThisModule decls env
	| otherwise = 
	   case lookupFM mod_map m of
	     Just iface -> iface_orig_exports iface
	     Nothing    -> trace ("Warning: module not found: " ++ show m) []

    findDecl :: HsQName -> Maybe HsDecl
    findDecl (UnQual n)
	= Nothing	-- must be a name we couldn't resolve
    findDecl (Qual m n)
	| m == mod  = lookupFM decl_map n
	| otherwise = 
	   case lookupFM mod_map m of
		Just iface -> lookupFM (iface_decls iface) n
		Nothing -> 
		   trace ("Warning: module not found: " ++ show m) Nothing

fullContentsOfThisModule decls env = 
  [ mkExportItem decl | decl <- decls, keepDecl decl ]
  where mkExportItem (HsDocGroup lev str) =
	   ExportGroup lev "" doc
	  where
	   (doc, _names) = formatDocHeading (lookupForDoc env) str
	   -- ToDo: report the unresolved names
	mkExportItem decl = ExportDecl decl


keepDecl HsTypeSig{}     = True
keepDecl HsTypeDecl{}    = True
keepDecl HsNewTypeDecl{} = True
keepDecl HsDataDecl{}    = True
keepDecl HsClassDecl{}   = True
keepDecl HsDocGroup{}	 = True
keepDecl _ = False

-- -----------------------------------------------------------------------------
-- Gather a list of original names exported from this module

exportedNames :: Module -> ModuleMap -> [HsDecl] -> [HsName]
	-> Maybe [HsExportSpec]
	-> FiniteMap HsName HsDecl
	-> [HsQName]
exportedNames mod mod_scope decls local_names Nothing decl_map
  = map (Qual mod) local_names
exportedNames mod mod_scope decls local_names (Just expspecs) decl_map
  = concat (map extract expspecs)
 where
  extract e = 
   case e of
    HsEVar x -> [x]
    HsEAbs t -> [t]
    HsEThingAll t
	|  Just decl <- export_lookup t 
	-> t : map (Qual t_mod) (declBinders decl)
	where t_mod = case t of Qual m _ -> m; otherwise -> mod
    HsEThingWith t cs -> t : cs
    HsEModuleContents m
	| m == mod  -> map (Qual mod) local_names
	| otherwise ->
	  case lookupFM mod_scope m of
	    Just iface -> eltsFM (iface_env iface)
	    Nothing    -> trace ("Warning: module not found: " ++ show m) $ []
    _ -> []

  export_lookup :: HsQName -> Maybe HsDecl
  export_lookup (UnQual n)
	= trace ("Warning(exportedNames): UnQual! " ++ show n) $ Nothing
  export_lookup (Qual m n)
	| m == mod  = lookupFM decl_map n
	| otherwise
	    = case lookupFM mod_scope m of
		Just iface -> lookupFM (iface_decls iface) n
		Nothing    -> trace ("Warning: module not found: " ++ show m) 
				Nothing

-- -----------------------------------------------------------------------------
-- Building name environments

buildEnv :: ModuleMap -> Module -> [HsQName] -> HsImportDecl
   -> ( FiniteMap HsQName HsQName, 	-- source name ==> orig name
        FiniteMap HsQName HsQName	-- orig name ==> import name
      )
buildEnv mod_map this_mod exported_names (HsImportDecl _ mod qual _ _)
   = case lookupFM mod_map mod of
       Nothing    -> trace ("Warning: module not found: " ++ show mod) 
			(emptyFM, emptyFM)
       Just iface -> 
	  let env = fmToList (iface_env iface) in
	  ( listToFM (concat (map orig_map env))
	  , listToFM (map import_map env)
  	  )
  where
	-- bring both qualified and unqualified names into scope, unless
	-- the import was 'qualified'.
     orig_map (nm,qnm)
	| qual      = [ (Qual mod nm, qnm) ]
	| otherwise = [ (UnQual nm, qnm), (Qual mod nm, qnm) ]

     import_map (nm,qnm) = (qnm, maps_to)
	where maps_to | qnm `elem` exported_names = Qual this_mod nm
		      | otherwise = Qual mod nm

-- -----------------------------------------------------------------------------
-- Expand multiple type signatures

expandDecl :: HsDecl -> [HsDecl]
expandDecl (HsTypeSig loc fs qt) = [ HsTypeSig loc [f] qt | f <- fs ]
expandDecl (HsClassDecl loc ty decls)
  = [ HsClassDecl loc ty (concat (map expandDecl decls)) ]
expandDecl d = [ d ]

-----------------------------------------------------------------------------
-- Collecting documentation and associating it with declarations

collectDoc :: [HsDecl] -> [(HsName, DocString)]
collectDoc decls = collect Nothing "" decls

collect name doc_so_far [] = 
   case name of
	Nothing -> []
	Just n  -> finishedDoc n doc_so_far []

collect name doc_so_far (decl:ds) = 
   case decl of
      HsDocCommentNext str -> 
	case name of
	   Nothing -> collect name (doc_so_far ++ str) ds
	   Just n  -> finishedDoc n doc_so_far (collect Nothing str ds)

      HsDocCommentPrev str -> collect name (doc_so_far++str) ds

      _other -> 
	docsFromDecl decl ++
	case name of
	    Nothing -> collect bndr doc_so_far ds
	    Just n  -> finishedDoc n doc_so_far (collect bndr "" ds)
        where 
	    bndr = declMainBinder decl

finishedDoc n s rest | all isSpace s = rest
 	             | otherwise     = (n,s) : rest

-- look inside a declaration and get docs for the bits
-- (constructors, record fields, class methods)
docsFromDecl :: HsDecl -> [(HsName, DocString)]
docsFromDecl (HsDataDecl loc ctxt nm tvs cons drvs)
  = concat (map docsFromConDecl cons)
docsFromDecl (HsNewTypeDecl loc ctxt nm tvs con drvs)
  = docsFromConDecl con
docsFromDecl (HsClassDecl loc ty decls)
  = collect Nothing "" decls
docsFromDecl _
  = []

docsFromConDecl :: HsConDecl -> [(HsName, DocString)]
docsFromConDecl (HsConDecl loc nm tys (Just doc))
  = finishedDoc nm doc []
docsFromConDecl (HsRecDecl loc nm fields (Just doc))
  = finishedDoc nm doc (foldr docsFromField [] fields)
docsFromConDecl (HsRecDecl loc nm fields Nothing)
  = foldr docsFromField [] fields
docsFromConDecl _ 
  = []

docsFromField (HsFieldDecl nms ty (Just doc)) rest
  = foldr (\n -> finishedDoc n doc) rest nms
docsFromField (HsFieldDecl nms ty Nothing) rest
  = rest

-----------------------------------------------------------------------------
-- formatting is done in two stages.  Firstly we partially apply
-- formatDocString to the lookup function and the DocString to get a
-- markup-independent string.  Finally the back ends apply the markup
-- description to this function to get the marked-up text.

-- this one formats a heading
formatDocHeading :: (String -> Maybe HsQName) -> DocString
  -> (Doc,[String])
formatDocHeading lookup string = format parseString lookup string

-- this one formats a sequence of paragraphs
formatDocString :: (String -> Maybe HsQName) -> DocString
  -> (Doc,[String])
formatDocString lookup string = format parseParas lookup string

format 	:: ([Token] -> Either String ParsedDoc)
	-> (String -> Maybe HsQName)
	-> DocString
       	-> (Doc, [String])
format parse lookup string
  = case parse (tokenise string) of
	Left error -> trace ("Warning: parse error in doc string beginning:\n\ 
			     \    " ++ take 40 string) (DocEmpty, [])
	Right doc -> runRn lookup (resolveDoc doc)
  

-- ---------------------------------------------------------------------------
-- Looking up names in documentation

lookupForDoc :: FiniteMap HsQName HsQName -> (String -> Maybe HsQName)
lookupForDoc fm str
  = case [ n | Just n <- map (lookupFM fm) (strToHsQNames str) ] of
	(n:_) -> Just n
	[] -> Nothing
 
strToHsQNames :: String -> [ HsQName ]
strToHsQNames str
 = case lexer (\t -> returnP t) str (SrcLoc 1 1) 1 1 [] of
	Ok _ (VarId str)
		-> [ UnQual (HsVarName (HsIdent str)) ]
        Ok _ (QVarId (mod,str))
		-> [ Qual (Module mod) (HsVarName (HsIdent str)) ]
	Ok _ (ConId str)
		-> [ UnQual (HsTyClsName (HsIdent str)),
		     UnQual (HsVarName (HsIdent str)) ]
        Ok _ (QConId (mod,str))
		-> [ Qual (Module mod) (HsTyClsName (HsIdent str)),
		     Qual (Module mod) (HsVarName (HsIdent str)) ]
        Ok _ (VarSym str)
		-> [ UnQual (HsVarName (HsSymbol str)) ]
        Ok _ (ConSym str)
		-> [ UnQual (HsTyClsName (HsSymbol str)),
		     UnQual (HsVarName (HsSymbol str)) ]
        Ok _ (QVarSym (mod,str))
		-> [ Qual (Module mod) (HsVarName (HsSymbol str)) ]
        Ok _ (QConSym (mod,str))
		-> [ Qual (Module mod) (HsTyClsName (HsSymbol str)),
		     Qual (Module mod) (HsVarName (HsSymbol str)) ]
	other -> []

-----------------------------------------------------------------------------
-- misc.

mapSnd f [] = []
mapSnd f ((x,y):xs) = (x,f y) : mapSnd f xs

mapMaybeM :: Monad m => (a -> m b) -> Maybe a -> m (Maybe b)
mapMaybeM f Nothing = return Nothing
mapMaybeM f (Just a) = f a >>= return . Just