//===--- DarwinSDKInfo.h - SDK Information parser for darwin ----*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

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

#ifndef LLVM_CLANG_BASIC_DARWINSDKINFO_H

#define LLVM_CLANG_BASIC_DARWINSDKINFO_H

#include "clang/Basic/LLVM.h"

#include "llvm/ADT/DenseMap.h"

#include "llvm/ADT/Triple.h"

#include "llvm/Support/Error.h"

#include "llvm/Support/VersionTuple.h"

#include "llvm/Support/VirtualFileSystem.h"

namespace llvm {

namespace json {

class Object;

} // end namespace json

} // end namespace llvm

namespace clang {

/// The information about the darwin SDK that was used during this compilation.

class DarwinSDKInfo {

public:

  /// A value that describes two os-environment pairs that can be used as a key

  /// to the version map in the SDK.

  struct OSEnvPair {

  public:

    using StorageType = uint64_t;

    constexpr OSEnvPair(llvm::Triple::OSType FromOS,

                        llvm::Triple::EnvironmentType FromEnv,

                        llvm::Triple::OSType ToOS,

                        llvm::Triple::EnvironmentType ToEnv)

        : Value(((StorageType(FromOS) * StorageType(llvm::Triple::LastOSType) +

                  StorageType(FromEnv))

                 << 32ull) |

                (StorageType(ToOS) * StorageType(llvm::Triple::LastOSType) +

                 StorageType(ToEnv))) {}

    /// Returns the os-environment mapping pair that's used to represent the

    /// macOS -> Mac Catalyst version mapping.

    static inline constexpr OSEnvPair macOStoMacCatalystPair() {

      return OSEnvPair(llvm::Triple::MacOSX, llvm::Triple::UnknownEnvironment,

                       llvm::Triple::IOS, llvm::Triple::MacABI);

    }

    /// Returns the os-environment mapping pair that's used to represent the

    /// Mac Catalyst -> macOS version mapping.

    static inline constexpr OSEnvPair macCatalystToMacOSPair() {

      return OSEnvPair(llvm::Triple::IOS, llvm::Triple::MacABI,

                       llvm::Triple::MacOSX, llvm::Triple::UnknownEnvironment);

    }

    /// Returns the os-environment mapping pair that's used to represent the

    /// iOS -> watchOS version mapping.

    static inline constexpr OSEnvPair iOStoWatchOSPair() {

      return OSEnvPair(llvm::Triple::IOS, llvm::Triple::UnknownEnvironment,

                       llvm::Triple::WatchOS, llvm::Triple::UnknownEnvironment);

    }

    /// Returns the os-environment mapping pair that's used to represent the

    /// iOS -> tvOS version mapping.

    static inline constexpr OSEnvPair iOStoTvOSPair() {

      return OSEnvPair(llvm::Triple::IOS, llvm::Triple::UnknownEnvironment,

                       llvm::Triple::TvOS, llvm::Triple::UnknownEnvironment);

    }

  private:

    StorageType Value;

    friend class DarwinSDKInfo;

  };

  /// Represents a version mapping that maps from a version of one target to a

  /// version of a related target.

  ///

  /// e.g. "macOS_iOSMac":{"10.15":"13.1"} is an example of a macOS -> Mac

  /// Catalyst version map.

  class RelatedTargetVersionMapping {

  public:

    RelatedTargetVersionMapping(

        VersionTuple MinimumKeyVersion, VersionTuple MaximumKeyVersion,

        VersionTuple MinimumValue, VersionTuple MaximumValue,

        llvm::DenseMap<VersionTuple, VersionTuple> Mapping)

        : MinimumKeyVersion(MinimumKeyVersion),

          MaximumKeyVersion(MaximumKeyVersion), MinimumValue(MinimumValue),

          MaximumValue(MaximumValue), Mapping(Mapping) {

      assert(!this->Mapping.empty() && "unexpected empty mapping");

    }

    /// Returns the value with the lowest version in the mapping.

    const VersionTuple &getMinimumValue() const { return MinimumValue; }

    /// Returns the mapped key, or the appropriate Minimum / MaximumValue if

    /// they key is outside of the mapping bounds. If they key isn't mapped, but

    /// within the minimum and maximum bounds, None is returned.

    Optional<VersionTuple> map(const VersionTuple &Key,

                               const VersionTuple &MinimumValue,

                               Optional<VersionTuple> MaximumValue) const;

    static Optional<RelatedTargetVersionMapping>

    parseJSON(const llvm::json::Object &Obj,

              VersionTuple MaximumDeploymentTarget);

  private:

    VersionTuple MinimumKeyVersion;

    VersionTuple MaximumKeyVersion;

    VersionTuple MinimumValue;

    VersionTuple MaximumValue;

    llvm::DenseMap<VersionTuple, VersionTuple> Mapping;

  };

  DarwinSDKInfo(VersionTuple Version, VersionTuple MaximumDeploymentTarget,

                llvm::DenseMap<OSEnvPair::StorageType,

                               Optional<RelatedTargetVersionMapping>>

                    VersionMappings =

                        llvm::DenseMap<OSEnvPair::StorageType,

                                       Optional<RelatedTargetVersionMapping>>())

      : Version(Version), MaximumDeploymentTarget(MaximumDeploymentTarget),

        VersionMappings(std::move(VersionMappings)) {}

  const llvm::VersionTuple &getVersion() const { return Version; }

  // Returns the optional, target-specific version mapping that maps from one

  // target to another target.

  //

  // This mapping is constructed from an appropriate mapping in the SDKSettings,

  // for instance, when building for Mac Catalyst, the mapping would contain the

  // "macOS_iOSMac" mapping as it maps the macOS versions to the Mac Catalyst

  // versions.

  //

  // This mapping does not exist when the target doesn't have an appropriate

  // related version mapping, or when there was an error reading the mapping

  // from the SDKSettings, or when it's missing in the SDKSettings.

  const RelatedTargetVersionMapping *getVersionMapping(OSEnvPair Kind) const {

    auto Mapping = VersionMappings.find(Kind.Value);

    if (Mapping == VersionMappings.end())

      return nullptr;

    return Mapping->getSecond().hasValue() ? Mapping->getSecond().getPointer()

                                           : 
nullptr0
;

  }

  static Optional<DarwinSDKInfo>

  parseDarwinSDKSettingsJSON(const llvm::json::Object *Obj);

private:

  VersionTuple Version;

  VersionTuple MaximumDeploymentTarget;

  // Need to wrap the value in an optional here as the value has to be default

  // constructible, and std::unique_ptr doesn't like DarwinSDKInfo being

  // Optional as Optional is trying to copy it in emplace.

  llvm::DenseMap<OSEnvPair::StorageType, Optional<RelatedTargetVersionMapping>>

      VersionMappings;

};

/// Parse the SDK information from the SDKSettings.json file.

///

/// \returns an error if the SDKSettings.json file is invalid, None if the

/// SDK has no SDKSettings.json, or a valid \c DarwinSDKInfo otherwise.

Expected<Optional<DarwinSDKInfo>> parseDarwinSDKInfo(llvm::vfs::FileSystem &VFS,

                                                     StringRef SDKRootPath);

} // end namespace clang

#endif // LLVM_CLANG_BASIC_DARWINSDKINFO_H