Language.hs

-- SPDX-FileCopyrightText: 2020 Tocqueville Group
--
-- SPDX-License-Identifier: LicenseRef-MIT-TQ

-- | Duplication of Backend functions, but without input and output stack.

module Indigo.Frontend.Language
  ( -- * Assignment and modifications
    new
  , setVar
  , setField
  , (+=)
  , (-=)
  , (*=)
  , (<<<=)
  , (>>>=)
  , (&&=)
  , (||=)
  , (^=)
  , (=:)

  -- * Storage Fields
  , getStorageField
  , setStorageField
  , updateStorageField

  -- * Conditional
  , if_
  , when
  , unless
  , ifSome
  , ifNone
  , whenSome
  , whenNone
  , ifRight
  , ifLeft
  , whenRight
  , whenLeft
  , ifCons

  -- * Case
  , case_
  , caseRec
  , entryCase
  , entryCaseRec
  , entryCaseSimple
  , (//->)

  -- * Scope
  , scope
  , defFunction
  , defContract
  , defNamedPureLambda1
  , defNamedLambda1
  , defNamedLambda0
  , defNamedEffLambda1

  -- * Loop
  , while
  , whileLeft
  , forEach

  -- * Contract call
  , selfCalling
  , contractCalling

  -- * Documentation
  , doc
  , docGroup
  , docStorage
  , contractName
  , contractGeneral
  , contractGeneralDefault
  , finalizeParamCallingDoc

  -- * Side-effects operations
  , transferTokens
  , setDelegate
  , createContract
  , createLorentzContract

  -- * Failures
  , failWith
  , assert
  , failCustom
  , failCustom_
  , failUnexpected_
  , assertCustom
  , assertCustom_

  -- * Comments
  , comment
  , justComment
  , commentAroundFun
  , commentAroundStmt

  -- * Blocks
  , IndigoFunction
  , IndigoProcedure
  , IndigoEntrypoint

  -- * Helpers
  , liftIndigoState
  ) where

import qualified Indigo.Backend as B
import Indigo.Backend.Case hiding (caseRec, entryCaseRec)
import Indigo.Backend.Lambda
import Indigo.Backend.Scope
import Indigo.Compilation (compileIndigoContract)
import Indigo.Frontend.Program
import Indigo.Frontend.Statement
import Indigo.Internal hiding (SetField, return, (>>), (>>=))
import Indigo.Lorentz
import Indigo.Prelude
import Lorentz.EntryPoints.Helpers (RequireSumType)
import qualified Lorentz.Instr as L
import qualified Lorentz.Run as L
import qualified Michelson.Typed as MT
import qualified Michelson.Typed.Arith as M
import Michelson.Typed.Haskell.Instr.Sum (CaseClauseParam(..), CtorField(..))
import Util.TypeLits (AppendSymbol)
import Util.TypeTuple.Class

oneIndigoM :: StatementF IndigoM a -> IndigoM a
oneIndigoM st = IndigoM (Instr st)

liftIndigoState :: (forall inp. SomeIndigoState inp a) -> IndigoM a
liftIndigoState code = IndigoM (Instr $ LiftIndigoState code)

varModification
  :: (IsExpr ey y, IsObject x)
  => ([y, x] :-> '[x]) -> Var x -> ey -> IndigoM ()
varModification act v ex = oneIndigoM $ VarModification act v ex

----------------------------------------------------------------------------
-- Var creation and assignment
----------------------------------------------------------------------------

-- | Create a new variable with the result of the given expression as its initial value.
new :: IsExpr ex x => ex -> IndigoM (Var x)
new e = oneIndigoM $ NewVar e

-- | Set the given variable to the result of the given expression.
setVar :: (IsExpr ex x, IsObject x) => Var x -> ex -> IndigoM ()
setVar v e = oneIndigoM $ SetVar v e

infixr 0 =:
(=:) :: (IsExpr ex x, IsObject x) => Var x -> ex -> IndigoM ()
v =: e = setVar v e

setField
  :: ( ex :~> ftype
     , IsObject dt
     , IsObject ftype
     , HasField dt fname ftype
     )
  => Var dt -> Label fname -> ex -> IndigoM ()
setField v fName e = oneIndigoM $ SetField v fName e

(+=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Add n m, ArithResHs M.Add n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(+=) = varModification L.add

(-=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Sub n m, ArithResHs M.Sub n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(-=) = varModification L.sub

(*=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Mul n m, ArithResHs M.Mul n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(*=) = varModification L.mul

(||=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Or n m, ArithResHs M.Or n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(||=) = varModification L.or

(&&=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.And n m, ArithResHs M.And n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(&&=) = varModification L.and

(^=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Xor n m, ArithResHs M.Xor n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(^=) = varModification L.xor

(<<<=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Lsl n m, ArithResHs M.Lsl n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(<<<=) = varModification L.lsl

(>>>=)
  :: ( IsExpr ex1 n, IsObject m
     , ArithOpHs M.Lsr n m, ArithResHs M.Lsr n m ~ m
     ) => Var m -> ex1 -> IndigoM ()
(>>>=) = varModification L.lsr

----------------------------------------------------------------------------
-- Storage Fields
----------------------------------------------------------------------------

-- | Sets a storage field to a new value.
setStorageField
  :: forall store name ftype ex.
     ( HasStorage store
     , ex :~> ftype
     , IsObject store
     , IsObject ftype
     , HasField store name ftype
     )
  => Label name -> ex -> IndigoM ()
setStorageField field expr = setField (storageVar @store) field expr

-- | Updates a storage field by using an updating 'IndigoM'.
updateStorageField
  :: forall store ftype fname fex.
     ( HasStorage store
     , fex :~> ftype
     , HasField store fname ftype
     , IsObject store
     , IsObject ftype
     )
  => Label fname
  -> (Var ftype -> IndigoM fex)
  -> IndigoM ()
updateStorageField field upd = scope $ do
  let storage = storageVar @store
  fieldVar <- new$ storage #! field
  expr <- upd fieldVar
  setField storage field expr

-- | Get a field from the storage, returns a variable.
--
-- Note that the storage type almost always needs to be specified.
getStorageField
  :: forall store ftype fname .
     ( HasStorage store
     , HasField store fname ftype
     )
  => Label fname -> IndigoM (Var ftype)
getStorageField field = new$ storageVar @store #! field

----------------------------------------------------------------------------
-- Conditional
----------------------------------------------------------------------------

if_
  :: forall a b ex . (IfConstraint a b, ex :~> Bool)
  => ex
  -> IndigoM a
  -> IndigoM b
  -> IndigoM (RetVars a)
if_ ex tb fb = oneIndigoM $ If ex tb fb

-- | Run the instruction when the condition is met, do nothing otherwise.
when :: (exc :~> Bool) => exc -> IndigoM () -> IndigoM ()
when cond expr = if_ cond expr (return ())

-- | Reverse of 'when'.
unless :: (exc :~> Bool) => exc -> IndigoM () -> IndigoM ()
unless cond expr = if_ cond (return ()) expr

ifSome
  :: forall x a b ex . (KnownValue x, ex :~> Maybe x, IfConstraint a b)
  => ex
  -> (Var x -> IndigoM a)
  -> IndigoM b
  -> IndigoM (RetVars a)
ifSome ex tb fb = oneIndigoM $ IfSome ex tb fb

ifNone
  :: forall x a b ex . (KnownValue x, ex :~> Maybe x, IfConstraint a b)
  => ex
  -> IndigoM b
  -> (Var x -> IndigoM a)
  -> IndigoM (RetVars a)
ifNone ex fb tb = ifSome ex tb fb

-- | Run the instruction when the given expression returns 'Just' a value,
-- do nothing otherwise.
whenSome
  :: forall x exa .
     ( KnownValue x
     , exa :~> Maybe x
     )
  => exa
  -> (Var x -> IndigoM ())
  -> IndigoM ()
whenSome c f = ifSome c f (return ())

-- | Run the instruction when the given expression returns 'Nothing',
-- do nothing otherwise.
whenNone
  :: forall x exa .
     ( KnownValue x
     , exa :~> Maybe x
     )
  => exa
  -> IndigoM ()
  -> IndigoM ()
whenNone c f = ifSome c (\_ -> return ()) f

ifRight
  :: forall x y a b ex .
     ( KnownValue x
     , KnownValue y
     , ex :~> Either y x
     , IfConstraint a b
     )
  => ex
  -> (Var x -> IndigoM a)
  -> (Var y -> IndigoM b)
  -> IndigoM (RetVars a)
ifRight ex rb lb = oneIndigoM $ IfRight ex rb lb

ifLeft
  :: forall x y a b ex .
     ( KnownValue x
     , KnownValue y
     , ex :~> Either y x
     , IfConstraint a b
     )
  => ex
  -> (Var y -> IndigoM b)
  -> (Var x -> IndigoM a)
  -> IndigoM (RetVars a)
ifLeft ex lb rb = ifRight ex rb lb

whenRight
  :: forall x y ex .
     ( KnownValue x
     , KnownValue y
     , ex :~> Either y x
     )
  => ex
  -> (Var x -> IndigoM ())
  -> IndigoM ()
whenRight c f = ifRight c f (\_ -> return ())

whenLeft
  :: forall x y ex .
     ( KnownValue x
     , KnownValue y
     , ex :~> Either y x
     )
  => ex
  -> (Var y -> IndigoM ())
  -> IndigoM ()
whenLeft c f = ifRight c (\_ -> return ()) f

ifCons
  :: forall x a b ex . (KnownValue x, ex :~> List x, IfConstraint a b)
  => ex
  -> (Var x -> Var (List x) -> IndigoM a)
  -> IndigoM b
  -> IndigoM (RetVars a)
ifCons ex tb fb = oneIndigoM $ IfCons ex tb fb

----------------------------------------------------------------------------
-- Case
----------------------------------------------------------------------------

-- | A case statement for indigo. See examples for a sample usage.
caseRec
  :: forall dt guard ret clauses .
     CaseCommonF (IndigoMCaseClauseL IndigoM) dt guard ret clauses
  => guard
  -> clauses
  -> IndigoM (RetVars ret)
caseRec = oneIndigoM ... Case

-- | 'caseRec' for tuples.
case_
  :: forall dt guard ret clauses.
     ( CaseCommonF (IndigoMCaseClauseL IndigoM) dt guard ret clauses
     , RecFromTuple clauses
     )
  => guard
  -> IsoRecTuple clauses
  -> IndigoM (RetVars ret)
case_ g = caseRec g . recFromTuple @clauses


-- | 'caseRec' for pattern-matching on parameter.
entryCaseRec
  :: forall dt entryPointKind guard ret clauses .
     ( CaseCommonF (IndigoMCaseClauseL IndigoM) dt guard ret clauses
     , DocumentEntryPoints entryPointKind dt
     )
  => Proxy entryPointKind
  -> guard
  -> clauses
  -> IndigoM (RetVars ret)
entryCaseRec proxy g cls = oneIndigoM $ EntryCase proxy g cls

-- | 'entryCaseRec' for tuples.
entryCase
  :: forall dt entryPointKind guard ret clauses .
     ( CaseCommonF (IndigoMCaseClauseL IndigoM) dt guard ret clauses
     , RecFromTuple clauses
     , DocumentEntryPoints entryPointKind dt
     )
  => Proxy entryPointKind
  -> guard
  -> IsoRecTuple clauses
  -> IndigoM (RetVars ret)
entryCase proxy g = entryCaseRec proxy g . recFromTuple @clauses

entryCaseSimple
  :: forall cp guard ret clauses .
     ( CaseCommonF (IndigoMCaseClauseL IndigoM) cp guard ret clauses
     , RecFromTuple clauses
     , DocumentEntryPoints PlainEntryPointsKind cp
     , NiceParameterFull cp
     , RequireFlatParamEps cp
     )
  => guard
  -> IsoRecTuple clauses
  -> IndigoM (RetVars ret)
entryCaseSimple g = oneIndigoM . EntryCaseSimple g . recFromTuple @clauses

-- | Use this instead of '/->'.
--
-- This operator is like '/->' but wraps a body into 'IndigoAnyOut',
-- which is needed for two reasons: to allow having any output stack
-- and to allow returning not exactly the same values.
(//->)
  :: ( CaseArrow name (Var x -> IndigoAnyOut x ret)
                      (IndigoCaseClauseL ret ('CaseClauseParam ctor ('OneField x)))
     , ScopeCodeGen retBr
     , ret ~ RetExprs retBr
     , RetOutStack ret ~ RetOutStack retBr
     , KnownValue x
     , name ~ (AppendSymbol "c" ctor)
     )
  => Label name
  -> (Var x -> IndigoM retBr)
  -> IndigoMCaseClauseL IndigoM ret ('CaseClauseParam ctor ('OneField x))
(//->) cName b = OneFieldIndigoMCaseClauseL cName b
infixr 0 //->

----------------------------------------------------------------------------
-- Scope & Functions
----------------------------------------------------------------------------

-- | Utility type for an 'IndigoM' that adds one element to the stack and returns
-- a variable pointing at it.
type IndigoFunction ret = IndigoM (RetVars ret)

-- | Utility type for an 'IndigoM' that does not modify the stack (only the
-- values in it) and returns nothing.
type IndigoProcedure = IndigoM ()

type IndigoEntrypoint param = param -> IndigoProcedure

scope
  :: forall a . ScopeCodeGen a
  => IndigoM a
  -> IndigoFunction a
scope = oneIndigoM . Scope

-- | Alias for 'scope' we use in the tutorial.
defFunction
  :: forall a . ScopeCodeGen a
  => IndigoM a
  -> IndigoFunction a
defFunction = scope

-- | A more specific version of 'defFunction' meant to more easily create
-- 'IndigoContract's.
--
-- Used in the tutorial. The 'HasSideEffects' constraint is
-- specified to avoid the warning for redundant constraints.
defContract
  :: (HasSideEffects => IndigoM ())
  -> (HasSideEffects => IndigoProcedure)
defContract = scope

-- | Family of @defNamed*LambdaN@ functions put an Indigo computation
-- on the stack to later call it avoiding code duplication.
-- @defNamed*LambdaN@ takes a computation with N arguments.
-- This family of functions add some overhead to contract byte size
-- for every call of the function,
-- therefore, DON'T use @defNamed*LambdaN@ if:
-- * Your computation is pretty small.
--   It would be cheaper just to inline it, so use 'defFunction'.
-- * Your computation is called only once, in this case also use 'defFunction'.
--
-- Also, pay attention that @defNamed*LambdaN@ accepts a string that is
-- a name of the passed computation. Be careful and make sure that all
-- declared computations have different names.
-- Later the name will be removed.
--
-- Pay attention, that lambda argument will be evaluated
-- to variable before lambda calling.
--
-- TODO Approach with lambda names has critical pitfall:
-- in case if a function takes @Label name@, lambda body
-- won't be regenerated for every different label.
-- So be carefully, this will be fixed in a following issue.
defNamedEffLambda1
  :: forall st argExpr res .
  ( ToExpr argExpr
  , Typeable res
  , ExecuteLambdaEff1C st (ExprType argExpr) res
  , CreateLambdaEff1C st (ExprType argExpr) res)
  => String
  -> (Var (ExprType argExpr) -> IndigoM res)
  -> (argExpr -> IndigoM (RetVars res))
defNamedEffLambda1 lName body = \ex ->
  oneIndigoM $ LambdaEff1Call (Proxy @st) lName body (toExpr ex)

-- | Like defNamedEffLambda1 but doesn't make side effects.
defNamedLambda1
  :: forall st argExpr res .
  ( ToExpr argExpr
  , Typeable res
  , ExecuteLambda1C st (ExprType argExpr) res
  , CreateLambda1C st (ExprType argExpr) res)
  => String
  -> (Var (ExprType argExpr) -> IndigoM res)
  -> (argExpr -> IndigoM (RetVars res))
defNamedLambda1 lName body = \ex ->
  oneIndigoM $ Lambda1Call (Proxy @st) lName body (toExpr ex)

-- | Like defNamedLambda1 but doesn't take an argument.
defNamedLambda0
  :: forall st res .
  ( Typeable res
  , ExecuteLambda1C st () res
  , CreateLambda1C st () res)
  => String
  -> IndigoM res
  -> IndigoM (RetVars res)
defNamedLambda0 lName body = oneIndigoM $ Lambda1Call (Proxy @st) lName (\(_ :: Var ()) -> body) (C ())

-- | Like defNamedEffLambda1 but doesn't modify storage and doesn't make side effects.
defNamedPureLambda1
  :: forall argExpr res .
  ( ToExpr argExpr
  , Typeable res
  , ExecuteLambdaPure1C (ExprType argExpr) res
  , CreateLambdaPure1C (ExprType argExpr) res)
  => String
  -> (Var (ExprType argExpr) -> IndigoM res)
  -> (argExpr -> IndigoM (RetVars res))
defNamedPureLambda1 lName body = \ex ->
  oneIndigoM $ LambdaPure1Call lName body (toExpr ex)

----------------------------------------------------------------------------
-- Loop
----------------------------------------------------------------------------

-- | While statement.
while :: forall ex . ex :~> Bool => ex -> IndigoM () -> IndigoM ()
while e body = oneIndigoM $ While e body

whileLeft
  :: forall x y ex .
     ( ex :~> Either y x
     , KnownValue y
     , KnownValue x
     )
  => ex
  -> (Var y -> IndigoM ())
  -> IndigoM (Var x)
whileLeft e body = oneIndigoM $ WhileLeft e body

-- | For statements to iterate over a container.
forEach
  :: forall a e . (IterOpHs a, KnownValue (IterOpElHs a), e :~> a)
  => e -> (Var (IterOpElHs a) -> IndigoM ())
  -> IndigoM ()
forEach container body = oneIndigoM $ ForEach container body

----------------------------------------------------------------------------
-- Documentation
----------------------------------------------------------------------------

-- | Put a document item.
doc :: DocItem di => di -> IndigoM ()
doc di = liftIndigoState $ toSIS $ B.doc di

-- | Group documentation built in the given piece of code
-- into a block dedicated to one thing, e.g. to one entrypoint.
docGroup :: DocGrouping -> IndigoM () -> IndigoM ()
docGroup = oneIndigoM ... DocGroup

-- | Insert documentation of the contract's storage type. The type
-- should be passed using type applications.
docStorage :: forall storage. TypeHasDoc storage => IndigoM ()
docStorage = liftIndigoState $ toSIS $ B.docStorage @storage

-- | Give a name to the given contract. Apply it to the whole contract code.
contractName :: Text -> IndigoM () -> IndigoM ()
contractName = oneIndigoM ... ContractName

-- | Attach general info to the given contract.
contractGeneral :: IndigoM () -> IndigoM ()
contractGeneral = oneIndigoM . ContractGeneral

-- | Attach default general info to the contract documentation.
contractGeneralDefault :: IndigoM ()
contractGeneralDefault = liftIndigoState $ toSIS $ B.contractGeneralDefault

-- | Indigo version for the homonym Lorentz function.
finalizeParamCallingDoc
  :: forall param x.
     ( ToExpr param
     , NiceParameterFull (ExprType param)
     , RequireSumType (ExprType param)
     , HasCallStack
     )
  => (Var (ExprType param) -> IndigoM x) -> (param -> IndigoM x)
finalizeParamCallingDoc = oneIndigoM ... FinalizeParamCallingDoc

----------------------------------------------------------------------------
-- Contract call
----------------------------------------------------------------------------

selfCalling
  :: forall p mname.
     ( NiceParameterFull p
     , KnownValue (GetEntryPointArgCustom p mname)
     )
  => EntryPointRef mname
  -> IndigoM (Var (ContractRef (GetEntryPointArgCustom p mname)))
selfCalling ep = liftIndigoState $ toSIS $ B.selfCalling @p ep

contractCalling
  :: forall cp epRef epArg addr exAddr.
     ( HasEntryPointArg cp epRef epArg
     , ToTAddress cp addr
     , ToT addr ~ ToT Address
     , exAddr :~> addr
     , KnownValue epArg
     )
  => epRef -> exAddr -> IndigoM (Var (Maybe (ContractRef epArg)))
contractCalling = oneIndigoM ... ContractCalling (Proxy @cp)

----------------------------------------------------------------------------
-- Side-effects operations
----------------------------------------------------------------------------

transferTokens
  :: (IsExpr exp p, IsExpr exm Mutez, IsExpr exc (ContractRef p), NiceParameter p, HasSideEffects)
  => exp -> exm -> exc -> IndigoM ()
transferTokens = oneIndigoM ... TransferTokens

setDelegate :: (HasSideEffects, IsExpr ex (Maybe KeyHash)) => ex -> IndigoM ()
setDelegate =  oneIndigoM ... SetDelegate

-- | Create contract using default compilation options for Lorentz compiler.
--
-- See "Lorentz.Run".
createContract
  :: ( IsObject st
     , IsExpr exk (Maybe KeyHash), IsExpr exm Mutez, IsExpr exs st
     , NiceStorage st, NiceParameterFull param
     , HasSideEffects
     )
  => (HasStorage st => Var param -> IndigoM ())
  -> exk
  -> exm
  -> exs
  -> IndigoM (Var Address)
createContract iCtr ek em es = oneIndigoM $ CreateContract (defaultContract $ compileIndigoContract iCtr) ek em es

-- | Create contract from raw Lorentz 'L.Contract'.
createLorentzContract
  :: ( IsObject st
     , IsExpr exk (Maybe KeyHash), IsExpr exm Mutez, IsExpr exs st
     , NiceStorage st, NiceParameterFull param
     , HasSideEffects
     )
  => L.Contract param st
  -> exk
  -> exm
  -> exs
  -> IndigoM (Var Address)
createLorentzContract lCtr ek em es = oneIndigoM $ CreateContract lCtr ek em es

----------------------------------------------------------------------------
-- Error
----------------------------------------------------------------------------

assert
  :: forall x ex.
     ( IsError x
     , IsExpr ex Bool
     )
  => x -> ex -> IndigoM ()
assert = oneIndigoM ... Assert

failWith
  :: forall r a ex . IsExpr ex a
  => ex -> IndigoM r
failWith = oneIndigoM . FailWith

failCustom
  :: forall r tag err ex.
     ( err ~ ErrorArg tag
     , CustomErrorHasDoc tag
     , NiceConstant err
     , ex :~> err
     )
  => Label tag -> ex -> IndigoM r
failCustom l errEx = oneIndigoM $ FailCustom l errEx

failCustom_
  :: forall r tag notVoidErrorMsg.
     ( RequireNoArgError tag notVoidErrorMsg
     , CustomErrorHasDoc tag
     )
  => Label tag -> IndigoM r
failCustom_ lab = liftIndigoState $ toSIS $ B.failCustom_ lab

failUnexpected_ :: MText -> IndigoM r
failUnexpected_ tx = liftIndigoState $ toSIS $ B.failUnexpected_ tx

assertCustom
  :: forall tag err errEx ex .
     ( err ~ ErrorArg tag
     , CustomErrorHasDoc tag
     , NiceConstant err
     , IsExpr errEx err
     , IsExpr ex Bool
     )
  => Label tag -> errEx -> ex -> IndigoM ()
assertCustom tag errEx e = if_ (toExpr e) (return ()) (failCustom tag errEx :: IndigoM ())

assertCustom_
  :: forall tag notVoidErrorMsg ex.
     ( RequireNoArgError tag notVoidErrorMsg
     , CustomErrorHasDoc tag
     , IsExpr ex Bool
     )
  => Label tag -> ex -> IndigoM ()
assertCustom_ tag e = if_ (toExpr e) (return ()) (failCustom_ tag :: IndigoM ())

----------------------------------------------------------------------------
-- Comments
----------------------------------------------------------------------------

-- | Add a comment in a generated Michelson code
justComment :: Text -> IndigoM ()
justComment = comment . MT.JustComment

-- | Add a comment in a generated Michelson code
comment :: MT.CommentType -> IndigoM ()
comment t = liftIndigoState $ toSIS (B.comment t)

-- | Add a comment before and after the given Indigo function code.
-- The first argument is the name of the function.
commentAroundFun :: Text -> IndigoM a -> IndigoM a
commentAroundFun fName body =
  comment (MT.FunctionStarts fName) >>
  body >>=
  \res -> res <$ comment (MT.FunctionEnds fName)

-- | Add a comment before and after the given Indigo statement code.
-- The first argument is the name of the statement.
commentAroundStmt :: Text -> IndigoM a -> IndigoM a
commentAroundStmt sName body =
  comment (MT.StatementStarts sName) >>
  body >>=
  \res -> res <$ comment (MT.StatementEnds sName)