#include "sub.h"

#include "codes.h"

#include <asm/assembler.h>
#include <asm/operators.h>

using namespace std::string_literals;

Op_sub::Op_sub(const Asm::Args& args)
{
 if (args[0].type() == typeid(Asm::Args::Register32) &&
     std::any_cast<Asm::Args::Register32>(args[0]).name() == "eax" &&
     args[1].type() == typeid(Asm::Args::Immediate32))
 { // sub eax, imm32 (before "sub reg32, imm32"! It's shorter.)
  machine_code = std::vector<uint8_t>{ 0x2D } + std::any_cast<Asm::Args::Immediate32>(args[1]).getCode();

 } else if (args[0].type() == typeid(Asm::Args::Register32) && args[1].type() == typeid(Asm::Args::Immediate32)) { // sub reg32, imm32
  machine_code = std::vector<uint8_t>{ 0x81 } + ModRM("/5", std::any_cast<Asm::Args::Register32>(args[0]).name()) + std::any_cast<Asm::Args::Immediate32>(args[1]).getCode();

 } else if (args[0].type() == typeid(Asm::Args::Register32) && args[1].type() == typeid(Asm::Args::Mem32Ptr64)) { // sub reg32, [reg64]
  machine_code = std::vector<uint8_t>{ 0x2B } + ModRM(std::any_cast<Asm::Args::Register32>(args[0]).name(), std::any_cast<Asm::Args::Mem32Ptr64>(args[1]).reg());

 } else if (args[0].type() == typeid(Asm::Args::Register16) && args[1].type() == typeid(Asm::Args::Mem16Ptr64)) { // sub reg16, [reg64]
  machine_code = OpSizePrefix() + std::vector<uint8_t>{ 0x2B } + ModRM(std::any_cast<Asm::Args::Register16>(args[0]).name(), std::any_cast<Asm::Args::Mem16Ptr64>(args[1]).reg());

 } else if (args[0].type() == typeid(Asm::Args::Register64) &&
            std::any_cast<Asm::Args::Register64>(args[0]).name() == "rax"  &&
            args[1].type() == typeid(Asm::Args::Immediate32))
 { // sub reg, imm32
  machine_code = REX("W") + machine_code = std::vector<uint8_t>{ 0x81 } + ModRM("/5", std::any_cast<Asm::Args::Register32>(args[0]).name()) + std::any_cast<Asm::Args::Immediate32>(args[1]).getCode();

 } else {
  throw std::runtime_error("Unimplemented: sub "s + args[0].type().name() + " "s + args[1].type().name());
 }
}

namespace {

bool registered {
 registerOp(mangleName<Asm::Args::Register32, Asm::Args::Immediate32>("sub"), [](const Asm::Args& args) -> std::shared_ptr<Op>{
                             return std::make_shared<Op_sub>(args);
                             }) &&
 registerOp(mangleName<Asm::Args::Register64, Asm::Args::Immediate32>("sub"), [](const Asm::Args& args) -> std::shared_ptr<Op>{
                             return std::make_shared<Op_sub>(args);
                             }) &&
 registerOp(mangleName<Asm::Args::Register16, Asm::Args::Mem16Ptr64>("sub"), [](const Asm::Args& args) -> std::shared_ptr<Op>{
                             return std::make_shared<Op_sub>(args);
                             }) &&
 registerOp(mangleName<Asm::Args::Register32, Asm::Args::Mem32Ptr64>("sub"), [](const Asm::Args& args) -> std::shared_ptr<Op>{
                             return std::make_shared<Op_sub>(args);
                             })
};

}