package wacc

import scala.collection.mutable
import parsley.{Failure, Success}
import scopt.OParser
import java.io.File

case class CliConfig(
    file: File = new File(".")
)

val cliBuilder = OParser.builder[CliConfig]
val cliParser = {
  import cliBuilder._
  OParser.sequence(
    programName("wacc-compiler"),
    help('h', "help")
      .text("Prints this help message"),
    arg[File]("<file>")
      .text("Input WACC source file")
      .required()
      .action((f, c) => c.copy(file = f))
      .validate(f =>
        if (!f.exists) failure("File does not exist")
        else if (!f.isFile) failure("File must be a regular file")
        else if (!f.getName.endsWith(".wacc"))
          failure("File must have .wacc extension")
        else success
      )
  )
}

def compile(contents: String): Int = {
  parser.parse(contents) match {
    case Success(prog) =>
      given errors: mutable.Builder[Error, List[Error]] = List.newBuilder
      val names = renamer.rename(prog)
      given ctx: typeChecker.TypeCheckerCtx = typeChecker.TypeCheckerCtx(names, errors)
      typeChecker.check(prog)
      if (errors.result.nonEmpty) {
        errors.result.foreach(println)
        200
      } else 0
    case Failure(msg) =>
      println(msg)
      100
  }
}

def main(args: Array[String]): Unit =
  OParser.parse(cliParser, args, CliConfig()) match {
    case Some(config) =>
      System.exit(compile(os.read(os.Path(config.file.getAbsolutePath))))
    case None =>
  }