#include "Instruction.h"

#include "Exceptions.h"

namespace x86 { 
  std::string Register2Str(x86::Register reg) {
    switch(reg){
    case x86::Register::EAX:    return "EAX";
    case x86::Register::ECX:    return "ECX";      
    case x86::Register::EDX:    return "EDX";      
    case x86::Register::EBX:    return "EBX";      
    case x86::Register::ESP:    return "ESP";      
    case x86::Register::EBP:    return "EBP";      
    case x86::Register::ESI:    return "ESI";      
    case x86::Register::EDI:    return "EDI";      
    }
    throw std::runtime_error("Register not found!");
  }

  SIB ProcessSIB(uint8_t sib) {
    uint8_t scale_mask = 0b11000000;
    uint8_t index_mask = 0b00111000;
    uint8_t base_mask  = 0b00000111;

    uint8_t scale = (sib & scale_mask) >> 6;
    uint8_t index = (sib & index_mask) >> 3;
    uint8_t base = sib & base_mask;

    if(index == 4) index = x86::Register::SIB_NONE;
    if(base == 4)  base  = x86::Register::SIB_DISP;

    return {.m_Scale = scale, .m_Index = (x86::Register)index, .m_Base = (x86::Register)base};	  
  }
}

std::string Opcode2Str(Opcode op) {
  switch(op) {
  case Opcode::INVALID:                    return "INVALID";
  case Opcode::ADD_RM32_R32:               return "ADD_RM32_R32";
  case Opcode::ADD_R32_RM32:               return "ADD_R32_RM32";
  case Opcode::MOV_R32_IMM32 ... 0xBF:     return "MOV_R32_IMM32";
  case Opcode::MOV_RM32_R32:               return "MOV_RM32_R32";
  case Opcode::NOP:                        return "NOP";
  case Opcode::HLT:                        return "HLT";
  }

  std::string what = "Opcode2Str could not find '" + std::to_string(op) + "'!"; 
  throw CPUException(what);
}