mtmc-web/src/jvmMain/kotlin/mtmc/asm/instructions/Instruction.kt

package mtmc.asm.instructions

import mtmc.asm.ASMElement
import mtmc.asm.Assembler
import mtmc.asm.instructions.ALUInstruction.Companion.disassemble
import mtmc.emulator.MonTanaMiniComputer.Companion.isDoubleWordInstruction
import mtmc.tokenizer.MTMCToken

abstract class Instruction(
  @JvmField val type: InstructionType,
  labels: List<MTMCToken>,
  @JvmField val instructionToken: MTMCToken
) : ASMElement(labels, instructionToken.line) {
  open fun validateLabel(assembler: Assembler) {
    // default does nothing
  }

  override fun addError(error: String) {
    addError(instructionToken, error)
  }

  abstract fun genCode(output: ByteArray, assembler: Assembler)

  override var sizeInBytes: Int = type.sizeInBytes
    get() = type.sizeInBytes

  companion object {
    @JvmStatic
    fun isInstruction(cmd: String): Boolean {
      return InstructionType.fromString(cmd) != null
    }

    fun disassemble(instruction: Short, previousInstruction: Short): String {
      if (isDoubleWordInstruction(previousInstruction)) {
        return instruction.toInt().toString()
      }
      val misc = MiscInstruction.disassemble(instruction)
      if (misc != null) {
        return misc
      }
      val aluOp = disassemble(instruction)
      if (aluOp != null) {
        return aluOp
      }
      val stack = StackInstruction.disassemble(instruction)
      if (stack != null) {
        return stack
      }
      val test = TestInstruction.disassemble(instruction)
      if (test != null) {
        return test
      }
      val lsr = LoadStoreRegisterInstruction.disassemble(instruction)
      if (lsr != null) {
        return lsr
      }
      val ls = LoadStoreInstruction.disassemble(instruction)
      if (ls != null) {
        return ls
      }
      val jumpReg = JumpInstruction.disassemble(instruction)
      if (jumpReg != null) {
        return jumpReg
      }
      val jump = JumpInstruction.disassemble(instruction)
      if (jump != null) {
        return jump
      }
      return "<unknown>"
    }
  }
}