/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

/*!
 * \file tvm/target/target_kind.h
 * \brief Target kind registry
 */
#ifndef TVM_TARGET_TARGET_KIND_H_
#define TVM_TARGET_TARGET_KIND_H_

#include <tvm/ffi/function.h>
#include <tvm/ffi/reflection/registry.h>
#include <tvm/ir/attr_registry_map.h>
#include <tvm/ir/config_schema.h>
#include <tvm/runtime/base.h>

#include <memory>
#include <unordered_map>
#include <utility>
#include <vector>

namespace tvm {

class Target;

/*!
 * \brief Target canonicalizer applied on instantiation of a given TargetKind.
 *
 * \param target_json Target in JSON format to be transformed during canonicalization.
 * \return The transformed Target JSON object.
 */
using FTargetCanonicalizer =
    ffi::TypedFunction<ffi::Map<ffi::String, ffi::Any>(ffi::Map<ffi::String, ffi::Any>)>;

class TargetInternal;

template <typename>
class TargetKindAttrMap;

/*! \brief Target kind, specifies the kind of the target */
class TargetKindNode : public ffi::Object {
 public:
  /*! \brief Name of the target kind */
  ffi::String name;
  /*! \brief Device type of target kind */
  int default_device_type;
  /*! \brief Default keys of the target */
  ffi::Array<ffi::String> default_keys;
  /*! \brief Function used to canonicalize a JSON target during creation */
  FTargetCanonicalizer target_canonicalizer;

  static void RegisterReflection() {
    namespace refl = tvm::ffi::reflection;
    refl::ObjectDef<TargetKindNode>()
        .def_ro("name", &TargetKindNode::name)
        .def_ro("default_device_type", &TargetKindNode::default_device_type,
                refl::AttachFieldFlag::SEqHashIgnore())
        .def_ro("default_keys", &TargetKindNode::default_keys,
                refl::AttachFieldFlag::SEqHashIgnore());
  }

  static constexpr TVMFFISEqHashKind _type_s_eq_hash_kind = kTVMFFISEqHashKindUniqueInstance;
  TVM_FFI_DECLARE_OBJECT_INFO_FINAL("target.TargetKind", TargetKindNode, ffi::Object);

 private:
  /*! \brief Return the index stored in attr registry */
  uint32_t AttrRegistryIndex() const { return index_; }
  /*! \brief Return the name stored in attr registry */
  ffi::String AttrRegistryName() const { return name; }
  /*! \brief ConfigSchema for validating and resolving target attributes */
  ir::ConfigSchema schema_;
  /*! \brief Index used for internal lookup of attribute registry */
  uint32_t index_;

  template <typename, typename>
  friend class AttrRegistry;
  template <typename>
  friend class AttrRegistryMapContainerMap;
  friend class TargetKindRegEntry;
  friend class TargetInternal;
};

/*!
 * \brief Managed reference class to TargetKindNode
 * \sa TargetKindNode
 */
class TargetKind : public ffi::ObjectRef {
 public:
  TargetKind() = default;
  explicit TargetKind(ffi::ObjectPtr<TargetKindNode> data) : ffi::ObjectRef(data) {
    TVM_FFI_ICHECK(data != nullptr);
  }
  /*! \brief Get the attribute map given the attribute name */
  template <typename ValueType>
  static inline TargetKindAttrMap<ValueType> GetAttrMap(const ffi::String& attr_name);
  /*!
   * \brief Retrieve the TargetKind given its name
   * \param target_kind_name Name of the target kind
   * \return The TargetKind requested
   */
  TVM_DLL static ffi::Optional<TargetKind> Get(const ffi::String& target_kind_name);
  /*! \brief Mutable access to the container class  */
  TargetKindNode* operator->() { return static_cast<TargetKindNode*>(data_.get()); }

  TVM_FFI_DEFINE_OBJECT_REF_METHODS_NOTNULLABLE(TargetKind, ffi::ObjectRef, TargetKindNode);

 private:
  TVM_DLL static const AttrRegistryMapContainerMap<TargetKind>& GetAttrMapContainer(
      const ffi::String& attr_name);
  friend class TargetKindRegEntry;
  friend class TargetInternal;
};

/*!
 * \brief ffi::Map<TargetKind, ValueType> used to store meta-information about TargetKind
 * \tparam ValueType The type of the value stored in map
 */
template <typename ValueType>
class TargetKindAttrMap : public AttrRegistryMap<TargetKind, ValueType> {
 public:
  using TParent = AttrRegistryMap<TargetKind, ValueType>;
  using TParent::count;
  using TParent::get;
  using TParent::operator[];
  explicit TargetKindAttrMap(const AttrRegistryMapContainerMap<TargetKind>& map) : TParent(map) {}
};

/*! \brief Value used with --runtime in target specs to indicate the C++ runtime. */
static constexpr const char* kTvmRuntimeCpp = "c++";

/*! \brief Value used with --runtime in target specs to indicate the C runtime. */
static constexpr const char* kTvmRuntimeCrt = "c";

/*!
 * \brief Helper structure to register TargetKind
 * \sa TVM_REGISTER_TARGET_KIND
 */
class TargetKindRegEntry {
 public:
  /*!
   * \brief Register additional attributes to target_kind.
   * \param attr_name The name of the attribute.
   * \param value The value to be set.
   * \param plevel The priority level of this attribute,
   *  an higher priority level attribute
   *  will replace lower priority level attribute.
   *  Must be bigger than 0.
   *
   *  Cannot set with same plevel twice in the code.
   *
   * \tparam ValueType The type of the value to be set.
   */
  template <typename ValueType>
  inline TargetKindRegEntry& set_attr(const ffi::String& attr_name, const ValueType& value,
                                      int plevel = 10);
  /*!
   * \brief Set DLPack's device_type the target
   * \param device_type Device type
   */
  inline TargetKindRegEntry& set_default_device_type(int device_type);
  /*!
   * \brief Set DLPack's device_type the target
   * \param keys The default keys
   */
  inline TargetKindRegEntry& set_default_keys(std::vector<ffi::String> keys);
  /*!
   * \brief Set the canonicalizer function applied upon target creation.
   * \param canonicalizer The target canonicalizer function.
   */
  inline TargetKindRegEntry& set_target_canonicalizer(FTargetCanonicalizer canonicalizer);
  /*!
   * \brief Register a valid configuration option and its ValueType for validation
   * \param key The configuration key
   * \param traits Optional traits (e.g. refl::DefaultValue, doc string, or raw default value)
   * \tparam ValueType The value type to be registered
   * \tparam Traits Optional trait types
   */
  template <typename ValueType, typename... Traits>
  inline TargetKindRegEntry& add_attr_option(const ffi::String& key, Traits&&... traits);
  /*! \brief Set name of the TargetKind to be the same as registry if it is empty */
  inline TargetKindRegEntry& set_name();
  /*!
   * \brief List all the entry names in the registry.
   * \return The entry names.
   */
  TVM_DLL static ffi::Array<ffi::String> ListTargetKinds();
  /*!
   * \brief Get all supported option names and types for a given Target kind.
   * \return Map of option name to type
   */
  TVM_DLL static ffi::Map<ffi::String, ffi::String> ListTargetKindOptions(const TargetKind& kind);

  /*!
   * \brief Register or get a new entry.
   * \param target_kind_name The name of the TargetKind.
   * \return the corresponding entry.
   */
  TVM_DLL static TargetKindRegEntry& RegisterOrGet(const ffi::String& target_kind_name);

 private:
  TargetKind kind_;
  ffi::String name;

  /*! \brief private constructor */
  explicit TargetKindRegEntry(uint32_t reg_index) : kind_(ffi::make_object<TargetKindNode>()) {
    kind_->index_ = reg_index;
  }
  /*!
   * \brief update the attribute TargetKindAttrMap
   * \param key The name of the attribute
   * \param value The value to be set
   * \param plevel The priority level
   */
  TVM_DLL void UpdateAttr(const ffi::String& key, ffi::Any value, int plevel);
  template <typename, typename>
  friend class AttrRegistry;
  friend class TargetKind;
};

template <typename ValueType>
inline TargetKindAttrMap<ValueType> TargetKind::GetAttrMap(const ffi::String& attr_name) {
  return TargetKindAttrMap<ValueType>(GetAttrMapContainer(attr_name));
}

template <typename ValueType>
inline TargetKindRegEntry& TargetKindRegEntry::set_attr(const ffi::String& attr_name,
                                                        const ValueType& value, int plevel) {
  TVM_FFI_ICHECK_GT(plevel, 0) << "plevel in set_attr must be greater than 0";
  ffi::Any rv;
  rv = value;
  UpdateAttr(attr_name, rv, plevel);
  return *this;
}

inline TargetKindRegEntry& TargetKindRegEntry::set_default_device_type(int device_type) {
  kind_->default_device_type = device_type;
  return *this;
}

inline TargetKindRegEntry& TargetKindRegEntry::set_default_keys(std::vector<ffi::String> keys) {
  kind_->default_keys = keys;
  return *this;
}

inline TargetKindRegEntry& TargetKindRegEntry::set_target_canonicalizer(
    FTargetCanonicalizer canonicalizer) {
  kind_->target_canonicalizer = canonicalizer;
  kind_->schema_.set_canonicalizer(canonicalizer);
  return *this;
}

template <typename ValueType, typename... Traits>
inline TargetKindRegEntry& TargetKindRegEntry::add_attr_option(const ffi::String& key,
                                                               Traits&&... traits) {
  kind_->schema_.def_option<ValueType>(key, std::forward<Traits>(traits)...);
  return *this;
}

inline TargetKindRegEntry& TargetKindRegEntry::set_name() {
  if (kind_->name.empty()) {
    kind_->name = name;
  }
  return *this;
}

#define TVM_TARGET_KIND_REGISTER_VAR_DEF \
  [[maybe_unused]] static ::tvm::TargetKindRegEntry& __make_##TargetKind

/*!
 * \def TVM_REGISTER_TARGET_KIND
 * \brief Register a new target kind, or set attribute of the corresponding target kind.
 *
 * \param TargetKindName The name of target kind
 * \param DeviceType The DLDeviceType of the target kind
 *
 * \code
 *
 *  TVM_REGISTER_TARGET_KIND("llvm")
 *  .set_attr<TPreCodegenPass>("TPreCodegenPass", a-pre-codegen-pass)
 *  .add_attr_option<Bool>("system_lib")
 *  .add_attr_option<ffi::String>("mtriple")
 *  .add_attr_option<ffi::String>("mattr");
 *
 * \endcode
 */
#define TVM_REGISTER_TARGET_KIND(TargetKindName, DeviceType)          \
  TVM_FFI_STR_CONCAT(TVM_TARGET_KIND_REGISTER_VAR_DEF, __COUNTER__) = \
      ::tvm::TargetKindRegEntry::RegisterOrGet(TargetKindName)        \
          .set_name()                                                 \
          .set_default_device_type(DeviceType)                        \
          .add_attr_option<ffi::String>("kind")                       \
          .add_attr_option<ffi::Array<ffi::String>>("keys")           \
          .add_attr_option<ffi::String>("tag")                        \
          .add_attr_option<ffi::String>("device")                     \
          .add_attr_option<ffi::String>("model")                      \
          .add_attr_option<ffi::Array<ffi::String>>("libs")           \
          .add_attr_option<Target>("host")                            \
          .add_attr_option<int64_t>("from_device")                    \
          .add_attr_option<int64_t>("target_device_type")

}  // namespace tvm

#endif  // TVM_TARGET_TARGET_KIND_H_