Get JSGF generation to compile. Still untested.

1 files changed, 114 insertions, 0 deletions

diff --git a/src-3.0/GF/Speech/JSGF.hs b/src-3.0/GF/Speech/JSGF.hs
new file mode 100644
index 000000000..53a40ffd4
--- /dev/null
+++ b/src-3.0/GF/Speech/JSGF.hs
@@ -0,0 +1,114 @@
+----------------------------------------------------------------------
+-- |
+-- Module      : GF.Speech.JSGF
+--
+-- This module prints a CFG as a JSGF grammar.
+--
+-- FIXME: remove \/ warn \/ fail if there are int \/ string literal
+-- categories in the grammar
+--
+-- FIXME: convert to UTF-8
+-----------------------------------------------------------------------------
+
+module GF.Speech.JSGF (jsgfPrinter) where
+
+import GF.Data.Utilities
+import GF.Speech.CFG
+import GF.Speech.RegExp
+import GF.Speech.SISR
+import GF.Speech.SRG
+import PGF.CId
+import PGF.Data
+
+import Data.Char
+import Data.List
+import Data.Maybe
+import Text.PrettyPrint.HughesPJ
+import Debug.Trace
+
+width :: Int
+width = 75
+
+jsgfPrinter :: Maybe SISRFormat
+	    -> PGF 
+            -> CId -> String
+jsgfPrinter sisr pgf cnc = renderStyle st $ prJSGF sisr $ makeSimpleSRG pgf cnc
+  where st = style { lineLength = width }
+
+prJSGF :: Maybe SISRFormat -> SRG -> Doc
+prJSGF sisr srg
+    = header $++$ mainCat $++$ foldr ($++$) empty (map prRule (srgRules srg))
+    where
+    header = text "#JSGF" <+> text "V1.0" <+> text "UTF-8" <+> lang <> char ';' $$
+             comment ("JSGF speech recognition grammar for " ++ srgName srg) $$
+             comment "Generated by GF" $$
+	     text ("grammar " ++ srgName srg ++ ";") 
+    lang = maybe empty text (srgLanguage srg)
+    mainCat = rule True "MAIN" [prCat (srgStartCat srg)]
+    prRule (SRGRule cat rhs) = rule (isExternalCat srg cat) cat (map prAlt rhs)
+    prAlt (SRGAlt mp n rhs) = sep [initTag, p (prItem sisr n rhs), finalTag]
+      where initTag | isEmpty t = empty
+                    | otherwise = text "<NULL>" <+>  t
+                where t = tag sisr (profileInitSISR n)
+            finalTag = tag sisr (profileFinalSISR n)
+            p = if isEmpty initTag && isEmpty finalTag then id else parens
+
+catFormId :: String -> String
+catFormId = (++ "_cat")
+
+prCat :: Cat -> Doc
+prCat c = char '<' <> text c <> char '>'
+
+prItem :: Maybe SISRFormat -> CFTerm -> SRGItem -> Doc
+prItem sisr t = f 0
+  where
+    f _ (REUnion [])  = text "<VOID>"
+    f p (REUnion xs) 
+        | not (null es) = brackets (f 0 (REUnion nes))
+        | otherwise = (if p >= 1 then parens else id) (alts (map (f 1) xs))
+      where (es,nes) = partition isEpsilon xs
+    f _ (REConcat []) = text "<NULL>"
+    f p (REConcat xs) = (if p >= 3 then parens else id) (fsep (map (f 2) xs))
+    f p (RERepeat x)  = f 3 x <> char '*'
+    f _ (RESymbol s)  = prSymbol sisr t s
+
+prSymbol :: Maybe SISRFormat -> CFTerm -> SRGSymbol -> Doc
+prSymbol sisr cn (NonTerminal n@(c,_)) = prCat c <+> tag sisr (catSISR cn n)
+prSymbol _ cn (Terminal t) | all isPunct t = empty  -- removes punctuation
+                           | otherwise = text t -- FIXME: quote if there is whitespace or odd chars
+
+tag :: Maybe SISRFormat -> (SISRFormat -> SISRTag) -> Doc
+tag Nothing _ = empty
+tag (Just fmt) t = case t fmt of
+                     [] -> empty
+                     ts -> char '{' <+> (text (e $ prSISR ts)) <+> char '}'
+  where e [] = []
+        e ('}':xs) = '\\':'}':e xs
+        e ('\n':xs) = ' ' : e (dropWhile isSpace xs)
+        e (x:xs) = x:e xs
+
+isPunct :: Char -> Bool
+isPunct c = c `elem` "-_.;.,?!"
+
+comment :: String -> Doc
+comment s = text "//" <+> text s
+
+alts :: [Doc] -> Doc
+alts = fsep . prepunctuate (text "| ")
+
+rule :: Bool -> Cat -> [Doc] -> Doc
+rule pub c xs = p <+> prCat c <+> char '=' <+> nest 2 (alts xs) <+> char ';'
+  where p = if pub then text "public" else empty
+
+-- Pretty-printing utilities
+
+emptyLine :: Doc
+emptyLine = text ""
+
+prepunctuate :: Doc -> [Doc] -> [Doc]
+prepunctuate _ [] = []
+prepunctuate p (x:xs) = x : map (p <>) xs
+
+($++$) :: Doc -> Doc -> Doc
+x $++$ y = x $$ emptyLine $$ y
+