package wacc

import wacc.ast.Position
import wacc.types._

enum Error {
  case DuplicateDeclaration(ident: ast.Ident)
  case UndefinedIdentifier(ident: ast.Ident, identType: renamer.IdentType)

  case FunctionParamsMismatch(pos: Position, expected: Int, got: Int)
  case SemanticError(pos: Position, msg: String)
  case TypeMismatch(pos: Position, expected: SemType, got: SemType, msg: String)
  case InternalError(pos: Position, msg: String)
}

def printError(error: Error)(using errorContent: String): Unit = {
  println("Semantic error:")
  error match {
    case Error.DuplicateDeclaration(ident) =>
      println(
        s"Duplicate declaration of identifier ${ident.v} at line: ${ident.getPosition.line} column: ${ident.getPosition.column}"
      )
      highlight(ident)
    case Error.UndefinedIdentifier(ident, identType) =>
      println(
        s"Undefined ${identType.toString.toLowerCase()} ${ident.v} at line: ${ident.getPosition.line} column: ${ident.getPosition.column}"
      )
      highlight(ident)
    case Error.FunctionParamsMismatch(ident, expected, got) =>
      println(s"Function ${ident.v} expects $expected parameters, got $got")
    case Error.TypeMismatch(expected, got) =>
      println(s"Type mismatch: expected $expected, got $got")
  }

}

def highlight(ident: ast.Ident)(using errorContent: String): Unit = {
  val lines = errorContent.split("\n")

  val preLine = if (ident.getPosition.line > 1) lines(ident.getPosition.line - 2) else ""
  val midLine = lines(ident.getPosition.line - 1)
  val postLine = lines(ident.getPosition.line)
  val linePointer = " " * (ident.getPosition.column) + ("^" * (ident.v.length)) + "\n"

  println(
    s">$preLine\n>$midLine\n$linePointer>$postLine"
  )

  // var lines: Iterator[String] = errorContent.linesIterator

  // lines = lines.drop(Math.max(0, ident.getPosition.line - 2))
  // println(s">${lines.next()}")
  // if (lines.hasNext)
  //   println(s">${lines.next()}")
  // println(" " * (ident.getPosition.column) + ("^" * (ident.v.length)))
  // if(lines.hasNext)
  //   println(s">${lines.next()}")
}