module Shpell.Analytics where

import Shpell.Parser 
import Control.Monad
import Control.Monad.State
import qualified Data.Map as Map
import Data.List
import Debug.Trace

checks = map runBasicAnalysis basicChecks

checkAll = checkList checks
checkList l t m = foldl (\x f -> f t x) m l

runBasicAnalysis f t m = snd $ runState (doAnalysis f t) m
basicChecks = [
    checkUuoc,
    checkForInQuoted,
    checkForInLs,
    checkMissingForQuotes,
    checkUnquotedExpansions,
    checkRedirectToSame
    ]

modifyMap = modify
addNoteFor id note = modifyMap $ Map.adjust (\(Metadata pos notes) -> Metadata pos (note:notes)) id

willSplit x = 
  case x of 
    T_DollarVariable _ _ -> True
    T_DollarBraced _ _ -> True
    T_DollarExpansion _ _ -> True
    T_BraceExpansion _ s -> True
    T_NormalWord _ l -> any willSplit l
    T_Literal _ s -> isGlob s
    _ -> False


isGlob str = any (`elem` str) "*?"

makeSimple (T_NormalWord _ [f]) = f
makeSimple (T_Redirecting _ _ f) = f
makeSimple t = t
simplify = doTransform makeSimple

deadSimple (T_NormalWord _ l) = [concat (concatMap (deadSimple) l)]
deadSimple (T_DoubleQuoted _ l) = ["\"" ++(concat (concatMap (deadSimple) l)) ++ "\""]
deadSimple (T_SingleQuoted _ s) = [s]
deadSimple (T_DollarVariable _ _) = ["${VAR}"]
deadSimple (T_DollarBraced _ _) = ["${VAR}"]
deadSimple (T_DollarArithmetic _ _) = ["${VAR}"]
deadSimple (T_DollarExpansion _ _) = ["${VAR}"]
deadSimple (T_Pipeline _ [x]) = deadSimple x
deadSimple (T_Literal _ x) = [x]
deadSimple (T_SimpleCommand _ vars words) = concatMap (deadSimple) words
deadSimple (T_Redirecting _ _ foo) = deadSimple foo
deadSimple _ = []

verify f s = checkBasic f s == Just True
verifyNot f s = checkBasic f s == Just False

checkBasic f s = case parseShell "-" s of 
        (ParseResult (Just (t, m)) _) -> Just . not $ (notesFromMap $ runBasicAnalysis f t m) == (notesFromMap m)
        _ -> Nothing



prop_checkUuoc = verify checkUuoc "cat foo | grep bar"
checkUuoc (T_Pipeline _ (T_Redirecting _ _ f@(T_SimpleCommand id _ _):_:_)) = 
    case deadSimple f of ["cat", _] -> addNoteFor id $ Note InfoC "UUOC: 'cat foo | bar | baz' is better written as 'bar < foo | baz'"
                         _ -> return ()
checkUuoc _ = return ()


prop_checkForInQuoted = verify checkForInQuoted "for f in \"$(ls)\"; do echo foo; done"
checkForInQuoted (T_ForIn _ f [T_NormalWord _ [T_DoubleQuoted id list]] _) = 
    when (any willSplit list) $ addNoteFor id $ Note ErrorC $ "Since you double quoted this, it will not word split, and the loop will only run once"
checkForInQuoted _ = return ()


prop_checkForInLs = verify checkForInLs "for f in $(ls *.mp3); do mplayer \"$f\"; done"
checkForInLs (T_ForIn _ f [T_NormalWord _ [T_DollarExpansion id [x]]] _) = 
    case deadSimple x of ("ls":n) -> let args = (if n == [] then ["*"] else n) in 
                                        addNoteFor id $ Note WarningC $ "Don't use 'for "++f++" in $(ls " ++ (intercalate " " n) ++ ")'. Use 'for "++f++" in "++ (intercalate " " args) ++ "'"
                         _ -> return ()
checkForInLs _ = return ()


prop_checkMissingForQuotes = verify checkMissingForQuotes "for f in *.mp3; do rm $f; done"
prop_checkMissingForQuotes2 = verifyNot checkMissingForQuotes "for f in foo bar; do rm $f; done"
checkMissingForQuotes (T_ForIn _ f words cmds) = 
    if not $ any willSplit words then return () else do
        mapM_  (doAnalysis (markUnquoted f)) cmds
  where 
    markUnquoted f (T_NormalWord _ l) = mapM_ mu l
    markUnquoted _ _ = return ()
    mu (T_DollarVariable id s) | s == f = warning id
    mu (T_DollarBraced id s) | s == f = warning id
    mu _ = return ()
    warning id = addNoteFor id $ Note WarningC $ "Variables that could contain spaces should be quoted"
checkMissingForQuotes _ = return ()


prop_checkUnquotedExpansions = verify checkUnquotedExpansions "rm $(ls)"
checkUnquotedExpansions (T_SimpleCommand _ _ cmds) = mapM_ check cmds 
    where check (T_NormalWord _ [T_DollarExpansion id _]) = addNoteFor id $ Note WarningC "Quote the expansion to prevent word splitting"
          check _ = return ()
checkUnquotedExpansions _ = return ()

prop_checkRedirectToSame = verify checkRedirectToSame "cat foo > foo"
prop_checkRedirectToSame2 = verify checkRedirectToSame "cat lol | sed -e 's/a/b/g' > lol"
prop_checkRedirectToSame3 = verifyNot checkRedirectToSame "cat lol | sed -e 's/a/b/g' > foo.bar && mv foo.bar lol"
checkRedirectToSame s@(T_Pipeline _ list) = 
    mapM_ (\l -> (mapM_ (\x -> doAnalysis (checkOccurences x) l) (getAllRedirs list))) list
  where checkOccurences (T_NormalWord exceptId x) (T_NormalWord newId y) = 
            when (x == y && exceptId /= newId) (do
                let note = Note InfoC $ "Make sure not to read and write the same file in the same pipeline"
                addNoteFor newId $ note
                addNoteFor exceptId $ note)
        checkOccurences _ _ = return ()
        getAllRedirs l = concatMap (\(T_Redirecting _ ls _) -> concatMap getRedirs ls) l
        getRedirs (T_FdRedirect _ _ (T_IoFile _ op file)) = 
                case op of T_Greater _ -> [file]
                           T_Less _    -> [file]
                           T_DGREAT _  -> [file]
                           _ -> []
        getRedirs _ = []
checkRedirectToSame _ = return ()


lt x = trace (show x) x