content: {-# LANGUAGE OverloadedStrings #-}
  {-# LANGUAGE GADTs #-}
  {-# LANGUAGE TypeOperators #-}
  {-# LANGUAGE ForeignFunctionInterface #-}
  
  -- Trevor's Future Haskell DSL for Neuro-Symbolic Reasoning
  -- This represents the evolution of Trevor's reasoning engine into a typed DSL
  
  module Trevor.Reasoning.DSL where
  
  import Control.Monad
  import Data.Text (Text)
  import Foreign.Ptr (Ptr)
  
  -- | Core types for the reasoning DSL
  data CodePatch = CodePatch
    { patchId :: Text
    , originalCode :: Text
    , modifiedCode :: Text
    , language :: Language
    } deriving (Show, Eq)
  
  data Language = Rust | Python | JavaScript | TypeScript | Haskell
    deriving (Show, Eq)
  
  -- | Invariants and pre/postconditions
  data Invariant a where
    TypeSafety :: Invariant ()
    MemorySafety :: Invariant ()
    NoDataRaces :: Invariant ()
    Termination :: Invariant ()
    Custom :: Text -> (CodePatch -> Bool) -> Invariant Bool
  
  -- | Contract specification
  data Contract = Contract
    { preconditions :: [Invariant Bool]
    , postconditions :: [Invariant Bool]
    , invariants :: [Invariant ()]
    }
  
  -- | Reasoning rules
  data Rule a where
    SyntaxRule :: Rule Bool
    SecurityRule :: Rule Double
    PerformanceRule :: Rule Double
    CompositeRule :: Rule a -> Rule b -> (a -> b -> c) -> Rule c
  
  -- | Algorithm choices
  data Strategy 
    = Conservative  -- Minimal changes, high safety
    | Balanced      -- Balanced approach
    | Aggressive    -- More extensive refactoring
    deriving (Show, Eq)
  
  -- | DSL for expressing reasoning logic
  class Reasoning m where
    applyRule :: Rule a -> CodePatch -> m a
    checkInvariant :: Invariant a -> CodePatch -> m a
    selectStrategy :: [Strategy] -> m Strategy
    combineScores :: [Double] -> m Double
  
  -- | Monadic reasoning context
  newtype ReasoningM a = ReasoningM { runReasoning :: IO a }
  
  instance Functor ReasoningM where
    fmap f (ReasoningM x) = ReasoningM (fmap f x)
  
  instance Applicative ReasoningM where
    pure = ReasoningM . pure
    ReasoningM f <*> ReasoningM x = ReasoningM (f <*> x)
  
  instance Monad ReasoningM where
    ReasoningM x >>= f = ReasoningM (x >>= runReasoning . f)
  
  instance Reasoning ReasoningM where
    applyRule SyntaxRule patch = pure True -- Simplified
    applyRule SecurityRule patch = pure 0.8 -- Simplified
    applyRule PerformanceRule patch = pure 0.9 -- Simplified
    applyRule (CompositeRule r1 r2 combine) patch = do
      a <- applyRule r1 patch
      b <- applyRule r2 patch
      pure (combine a b)
    
    checkInvariant TypeSafety _ = pure ()
    checkInvariant MemorySafety _ = pure ()
    checkInvariant NoDataRaces _ = pure ()
    checkInvariant Termination _ = pure ()
    checkInvariant (Custom name predicate) patch = pure (predicate patch)
    
    selectStrategy strategies = pure (head strategies)
    
    combineScores scores = pure (sum scores / fromIntegral (length scores))
  
  -- | High-level reasoning workflow
  analyzePatch :: CodePatch -> Contract -> Strategy -> ReasoningM Double
  analyzePatch patch contract strategy = do
    -- Check preconditions
    mapM_ (`checkInvariant` patch) (preconditions contract)
    
    -- Apply rules based on strategy
    scores <- case strategy of
      Conservative -> do
        syntax <- applyRule SyntaxRule patch
        security <- applyRule SecurityRule patch
        pure [if syntax then 1.0 else 0.0, security]
      
      Balanced -> do
        syntax <- applyRule SyntaxRule patch
        security <- applyRule SecurityRule patch
        performance <- applyRule PerformanceRule patch
        pure [if syntax then 1.0 else 0.0, security, performance]
      
      Aggressive -> do
        -- More comprehensive analysis
        syntax <- applyRule SyntaxRule patch
        security <- applyRule SecurityRule patch
        performance <- applyRule PerformanceRule patch
        composite <- applyRule (CompositeRule SecurityRule PerformanceRule (*)) patch
        pure [if syntax then 1.0 else 0.0, security, performance, composite]
    
    -- Combine scores
    finalScore <- combineScores scores
    
    -- Check postconditions and invariants
    mapM_ (`checkInvariant` patch) (postconditions contract)
    mapM_ (`checkInvariant` patch) (invariants contract)
    
    pure finalScore
  
  -- | Example usage
  exampleContract :: Contract
  exampleContract = Contract
    { preconditions = []
    , postconditions = [Custom "no_regression" (\_ -> True)]
    , invariants = [TypeSafety, MemorySafety]
    }
  
  -- | Future: Integration with Rust via FFI
  foreign import ccall "trevor_analyze_patch" 
    c_analyze_patch :: Ptr () -> IO Double
  
  -- | Future: Formal verification integration
  -- This would integrate with tools like Dafny, Coq, or Lean
  data Proof a = Proof Text
  
  verify :: Invariant a -> CodePatch -> ReasoningM (Maybe (Proof a))
  verify invariant patch = do
    -- Placeholder for formal verification
    pure Nothing
  
  -- | Example workflow that could be called from Rust
  main :: IO ()
  main = do
    let patch = CodePatch "example" "old code" "new code" Rust
    score <- runReasoning $ analyzePatch patch exampleContract Conservative
    putStrLn $ "Patch analysis score: " ++ show score