desugarVariantaLab

import Library._

object Desugar {


  def desugarList(es: List[ExprExt]): ExprC = es match {
    case h :: t => ConsC(desugar(h), desugarList(t))
    case h :: Nil => desugar(h)
    case _ => NilC()
  }

  def makeList(rows: List[ExprC]): ExprC = rows match {
    case rowList :: t => ConsC(rowList, makeList(t))
    case Nil => NilC()
  }

  def solveScalarMult(n: ExprC, m: ExprC): ExprC = m match {
    case ConsC(h, t) =>  ConsC(ListMapC(
      FdC("scalar-mult", MultC(n, IdC("scalar-mult"))), h)
      , solveScalarMult(n, t))
      case NilC() => NilC()
  }

  def desugar(e: ExprExt): ExprC = e match {
    case NumExt(n)           => NumC(n)
    case PlusExt(e1, e2)     => PlusC(desugar(e1), desugar(e2))
    case MultExt(e1, e2)     => MultC(desugar(e1), desugar(e2))
    case FdExt(x, e)         => FdC(x, desugar(e))
    case AppExt(f, a)        => AppC(desugar(f), desugar(a))
    case IdExt(x)            => IdC(x)
    case ConsExt(h, t)       => ConsC(desugar(h), desugar(t))
    case NilExt()            => NilC()

    case ListExt(es) =>
      desugarList(es)

    case ListMapExt(f, l) =>
      ListMapC(desugar(f), desugar(l))

    case MatrixExt(rs) =>
      val rows: List[ExprC] = rs.map(row => desugarList(row.es))
      makeList(rows)

    case ScalarMultExt(n, m) => solveScalarMult(desugar(n), desugar(m))
    // KEY
    // println(desugar(m))
    // desugar(m) match {
    // case ConsC(h, t) => println(h)
    // }
    // ListMapC(
    //   FdC("scalar-mult", MultC(desugar(n), IdC("scalar-mult"))), desugar(m)
    //   )

    // m match {
    //   case MatrixExt(rs) =>

    //     desugar(n) match {
    //       case num: NumC =>
    //           val rows: List[ExprC] = rs.map(row => row match {
    //           case RowExt(es) => desugarListMultiply(es, num)
    //         })
    //         //println(rows)
    //         makeList(rows)
    //       case _ => throw new RuntimeException(s"$n Does not evaluate to a number")
    //     }

    //   case _ => throw new RuntimeException(s"$m Does not evaluate to a matrix")

    // }



  }

}
//Expected ConsV(ConsV(NumV(3),ConsV(NumV(6),ConsV(NumV(9),NilV()))),ConsV(ConsV(NumV(12),ConsV(NumV(15),ConsV(NumV(18),NilV()))),NilV())),
// but got ConsV(ConsV(NumV(3),ConsV(NumV(2),ConsV(NumV(3),NilV()))),ConsV(ConsV(NumV(12),ConsV(NumV(5),ConsV(NumV(6),NilV()))),NilV()))