// SPDX-License-Identifier: Apache-2.0

// SPDX-FileCopyrightText: Copyright The WasmEdge Authors

//===-- wasmedge/common/enum_errcode.h - Error code C++ enumerations ------===//

//

// Part of the WasmEdge Project.

//

//===----------------------------------------------------------------------===//

///

/// \file

/// This file contains the C++ enumerations of WasmEdge error code.

///

//===----------------------------------------------------------------------===//

#pragma once

#include "common/dense_enum_map.h"

#include "common/fmt.h"

#include "common/spare_enum_map.h"

#include "common/spdlog.h"

#include <cstdint>

#include <string_view>

namespace WasmEdge {

/// WasmEdge runtime phasing C++ enumeration class.

enum class WasmPhase : uint8_t {

#define UseWasmPhase

#define Line(NAME, VALUE, STRING) NAME = VALUE,

#include "enum.inc"

#undef Line

#undef UseWasmPhase

};

static inline constexpr auto WasmPhaseStr = []() constexpr {

  using namespace std::literals::string_view_literals;

  std::pair<WasmPhase, std::string_view> Array[] = {

#define UseWasmPhase

#define Line(NAME, VALUE, STRING) {WasmPhase::NAME, STRING},

#include "enum.inc"

#undef Line

#undef UseWasmPhase

  };

  return DenseEnumMap(Array);

}();

/// Error category C++ enumeration class.

enum class ErrCategory : uint8_t {

#define UseErrCategory

#define Line(NAME, VALUE) NAME = VALUE,

#include "enum.inc"

#undef Line

#undef UseErrCategory

};

/// ErrCode wraps a compact uint32_t error code used throughout WasmEdge.

///

/// Note: Parameterized error messages (e.g., embedding function names or

/// indices into error strings) are intentionally NOT stored in this class.

/// Adding a std::string member would prevent ErrCode from being constexpr and

/// introduce implicit heap allocations on every copy in Expected<T, ErrCode>

/// return paths, causing significant performance regression (~10% release,

/// ~16% debug). See PR #4625 for benchmarks and discussion.

/// Contextual debug information should be logged separately via spdlog instead.

class ErrCode {

public:

  /// Error code C++ enumeration class.

  enum class Value : uint32_t {

#define UseErrCode

#define Line(NAME, VALUE, STRING) NAME = VALUE,

#include "enum.inc"

#undef Line

#undef UseErrCode

  };

  constexpr ErrCategory getCategory() const noexcept {

    return static_cast<ErrCategory>(static_cast<uint8_t>(Inner.Num >> 24));

  }

  constexpr uint32_t getCode() const noexcept {

    return Inner.Num & 0x00FFFFFFU;

  }

  constexpr ErrCode::Value getEnum() const noexcept {

    return getCategory() != ErrCategory::WASM

               ? ErrCode::Value::UserDefError

               : static_cast<ErrCode::Value>(getCode());

  }

  constexpr WasmPhase getErrCodePhase() const noexcept {

    return getCategory() != ErrCategory::WASM

               ? WasmPhase::UserDefined

               : static_cast<WasmPhase>((getCode() >> 8) & 0x0FU);

  }

  constexpr ErrCode() noexcept : Inner(0) {}

  constexpr ErrCode(const ErrCode &E) noexcept : Inner(E.Inner.Num) {}

  constexpr ErrCode(const ErrCode::Value E) noexcept : Inner(E) {}

  constexpr ErrCode(const uint32_t N) noexcept

      : Inner((static_cast<uint32_t>(ErrCategory::UserLevelError) << 24) +

              (N & 0x00FFFFFFU)) {}

  constexpr ErrCode(const ErrCategory C, const uint32_t N) noexcept

      : Inner((static_cast<uint32_t>(C) << 24) + (N & 0x00FFFFFFU)) {}

  friend constexpr bool operator==(const ErrCode &LHS,

                                   const ErrCode::Value &RHS) noexcept {

    return LHS.Inner.Code == RHS;

  }

  friend constexpr bool operator==(const ErrCode::Value &LHS,

                                   const ErrCode &RHS) noexcept {

    return RHS.Inner.Code == LHS;

  }

  friend constexpr bool operator==(const ErrCode &LHS,

                                   const ErrCode &RHS) noexcept {

    return LHS.Inner.Num == RHS.Inner.Num;

  }

  friend constexpr bool operator!=(const ErrCode &LHS,

                                   const ErrCode::Value &RHS) noexcept {

    return !(LHS == RHS);

  }

  friend constexpr bool operator!=(const ErrCode::Value &LHS,

                                   const ErrCode &RHS) noexcept {

    return !(LHS == RHS);

  }

  friend constexpr bool operator!=(const ErrCode &LHS,

                                   const ErrCode &RHS) noexcept {

    return !(LHS == RHS);

  }

  constexpr ErrCode &operator=(const ErrCode &) noexcept = default;

  constexpr operator uint32_t() const noexcept { return Inner.Num; }

private:

  union InnerT {

    constexpr InnerT(uint32_t Num) : Num(Num) {}

    constexpr InnerT(ErrCode::Value Code) : Code(Code) {}

    uint32_t Num;

    ErrCode::Value Code;

  } Inner;

};

static inline constexpr const auto ErrCodeStr = []() constexpr {

  using namespace std::literals::string_view_literals;

  std::pair<ErrCode::Value, std::string_view> Array[] = {

#define UseErrCode

#define Line(NAME, VALUE, STRING) {ErrCode::Value::NAME, STRING},

#include "enum.inc"

#undef Line

#undef UseErrCode

  };

  return SpareEnumMap(Array);

}();

} // namespace WasmEdge

template <>

struct fmt::formatter<WasmEdge::WasmPhase> : fmt::formatter<std::string_view> {

  template <typename FmtCtx>

  auto format(const WasmEdge::WasmPhase &Phase,

              FmtCtx &Ctx) WASMEDGE_FMT_CONST noexcept -> decltype(Ctx.out()) {

    return formatter<std::string_view>::format(WasmEdge::WasmPhaseStr[Phase],

                                               Ctx);

  }

};