/**
 ******************************************************************************
 * Xenia : Xbox 360 Emulator Research Project                                 *
 ******************************************************************************
 * Copyright 2020 Ben Vanik. All rights reserved.                             *
 * Released under the BSD license - see LICENSE in the root for more details. *
 ******************************************************************************
 */

#include "xenia/cpu/ppc/ppc_context.h"

#include <cstdlib>

#include "xenia/base/assert.h"
#include "xenia/base/string_util.h"

namespace xe {
namespace cpu {
namespace ppc {

uint64_t PPCContext::cr() const {
  uint64_t final_bits = 0;
  for (int i = 0; i < 8; ++i) {
    union {
      uint32_t value;
      struct {
        uint8_t lt;
        uint8_t gt;
        uint8_t eq;
        uint8_t so;
      };
    } crf;
    crf.value = *(&cr0.value + i);
    uint64_t bits = (crf.lt & 0x1) << 3 | (crf.gt & 0x1) << 2 |
                    (crf.eq & 0x1) << 1 | (crf.so & 0x1) << 0;
    final_bits |= bits << ((7 - i) * 4);
  }
  return final_bits;
}

void PPCContext::set_cr(uint64_t value) {
  assert_always("not yet implemented");
}

std::string PPCContext::GetRegisterName(PPCRegister reg) {
  switch (reg) {
    case PPCRegister::kLR:
      return "lr";
    case PPCRegister::kCTR:
      return "ctr";
    case PPCRegister::kXER:
      return "xer";
    case PPCRegister::kFPSCR:
      return "fpscr";
    case PPCRegister::kVSCR:
      return "vscr";
    case PPCRegister::kCR:
      return "cr";
    default:
      if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kR0) &&
          static_cast<int>(reg) <= static_cast<int>(PPCRegister::kR31)) {
        return std::string("r") +
               std::to_string(static_cast<int>(reg) -
                              static_cast<int>(PPCRegister::kR0));
      } else if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kFR0) &&
                 static_cast<int>(reg) <=
                     static_cast<int>(PPCRegister::kFR31)) {
        return std::string("fr") +
               std::to_string(static_cast<int>(reg) -
                              static_cast<int>(PPCRegister::kFR0));
      } else if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kVR0) &&
                 static_cast<int>(reg) <=
                     static_cast<int>(PPCRegister::kVR128)) {
        return std::string("vr") +
               std::to_string(static_cast<int>(reg) -
                              static_cast<int>(PPCRegister::kVR0));
      } else {
        assert_unhandled_case(reg);
        return "?";
      }
  }
}

std::string PPCContext::GetStringFromValue(PPCRegister reg) const {
  switch (reg) {
    case PPCRegister::kLR:
      return string_util::to_hex_string(lr);
    case PPCRegister::kCTR:
      return string_util::to_hex_string(ctr);
    case PPCRegister::kXER:
      // return Int64ToHex(xer_ca);
      return "?";
    case PPCRegister::kFPSCR:
      // return Int64ToHex(fpscr);
      return "?";
    case PPCRegister::kVSCR:
      // return Int64ToHex(vscr_sat);
      return "?";
    case PPCRegister::kCR:
      // return Int64ToHex(cr);
      return "?";
    default:
      if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kR0) &&
          static_cast<int>(reg) <= static_cast<int>(PPCRegister::kR31)) {
        return string_util::to_hex_string(
            r[static_cast<int>(reg) - static_cast<int>(PPCRegister::kR0)]);
      } else if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kFR0) &&
                 static_cast<int>(reg) <=
                     static_cast<int>(PPCRegister::kFR31)) {
        return string_util::to_hex_string(
            f[static_cast<int>(reg) - static_cast<int>(PPCRegister::kFR0)]);
      } else if (static_cast<int>(reg) >= static_cast<int>(PPCRegister::kVR0) &&
                 static_cast<int>(reg) <=
                     static_cast<int>(PPCRegister::kVR128)) {
        return string_util::to_hex_string(
            v[static_cast<int>(reg) - static_cast<int>(PPCRegister::kVR0)]);
      } else {
        assert_unhandled_case(reg);
        return "";
      }
  }
}

void PPCContext::SetValueFromString(PPCRegister reg, std::string value) {
  // TODO(benvanik): set value from string to replace SetRegFromString?
  assert_always(false);
}

void PPCContext::SetRegFromString(const char* name, const char* value) {
  int n;
  if (sscanf(name, "r%d", &n) == 1) {
    this->r[n] = string_util::from_string<uint64_t>(value);
  } else if (sscanf(name, "f%d", &n) == 1) {
    this->f[n] = string_util::from_string<double>(value);
  } else if (sscanf(name, "v%d", &n) == 1) {
    this->v[n] = string_util::from_string<vec128_t>(value);
  } else if (std::strcmp(name, "cr") == 0) {
    this->set_cr(string_util::from_string<uint64_t>(value));
  } else {
    printf("Unrecognized register name: %s\n", name);
  }
}

bool PPCContext::CompareRegWithString(const char* name, const char* value,
                                      std::string& result) const {
  int n;
  if (sscanf(name, "r%d", &n) == 1) {
    uint64_t expected = string_util::from_string<uint64_t>(value);
    if (this->r[n] != expected) {
      result = fmt::format("{:016X}", this->r[n]);
      return false;
    }
    return true;
  } else if (sscanf(name, "f%d", &n) == 1) {
    if (std::strstr(value, "0x")) {
      // Special case: Treat float as integer.
      uint64_t expected = string_util::from_string<uint64_t>(value, true);
      uint64_t pun;
      std::memcpy(&pun, &this->f[n], sizeof(pun));
      if (pun != expected) {
        result = fmt::format("{:016X}", pun);
        return false;
      }
    } else {
      double expected = string_util::from_string<double>(value);
      // TODO(benvanik): epsilon
      if (this->f[n] != expected) {
        result = fmt::format("{:.17f}", this->f[n]);
        return false;
      }
    }
    return true;
  } else if (sscanf(name, "v%d", &n) == 1) {
    vec128_t expected = string_util::from_string<vec128_t>(value);
    if (this->v[n] != expected) {
      result =
          fmt::format("[{:08X}, {:08X}, {:08X}, {:08X}]", this->v[n].i32[0],
                      this->v[n].i32[1], this->v[n].i32[2], this->v[n].i32[3]);
      return false;
    }
    return true;
  } else if (std::strcmp(name, "cr") == 0) {
    uint64_t actual = this->cr();
    uint64_t expected = string_util::from_string<uint64_t>(value);
    if (actual != expected) {
      result = fmt::format("{:016X}", actual);
      return false;
    }
    return true;
  } else {
    assert_always("Unrecognized register name: %s\n", name);
    return false;
  }
}

}  // namespace ppc
}  // namespace cpu
}  // namespace xe