/**
 * This is the C++ adaptation and derivative work of Myia (https://github.com/mila-iqia/myia/).
 *
 * Copyright 2019-2020 Huawei Technologies Co., Ltd
 *
 * Licensed 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.
 */

#include "ir/anf.h"

#include <algorithm>
#include <sstream>
#include <vector>
#include <unordered_map>

#include "base/core_ops.h"
#include "ir/func_graph.h"
#include "ir/primitive.h"
#include "utils/ms_context.h"

namespace mindspore {
// namespace to support intermediate representation definition
CNode::CNode(const std::vector<AnfNodePtr> &inputs, const FuncGraphPtr &func_graph)
    : AnfNode(func_graph), inputs_(inputs), stop_gradient_(false), output_value_(std::make_pair(nullptr, "")) {}

// Check if CNode is an apply with the specific Primitive.
bool CNode::IsApply(const PrimitivePtr &value) const {
  if (value == nullptr) {
    return false;
  }

  if (inputs_.size() != 0 && IsValueNode<Primitive>(inputs_[0])) {
    PrimitivePtr fn_value = GetValueNode<PrimitivePtr>(inputs_[0]);
    if (fn_value->Hash() == value->Hash() && fn_value->name() == value->name()) {
      return true;
    }
  }

  return false;
}

void CNode::set_input(size_t i, const AnfNodePtr &new_input) { inputs_[i] = new_input; }

std::string CNode::DebugString(int recursive_level) const {
  std::ostringstream buffer;
  if (recursive_level > 0) {
    if (func_graph() != nullptr) {
      buffer << func_graph()->ToString() << ":";
    }
    buffer << ToString() << "{";
    bool is_first_node = true;
    int idx = 0;
    for (auto &node : inputs_) {
      MS_EXCEPTION_IF_NULL(node);
      if (is_first_node) {
        is_first_node = false;
      } else {
        buffer << ", ";
      }
      buffer << "[" << idx << "]: " << node->DebugString(recursive_level - 1);
      idx++;
    }
    buffer << "}";
  } else {
    buffer << ToString();
  }
  return buffer.str();
}

std::string Parameter::DebugString(int recursive_level) const {
  std::ostringstream buffer;
  if (recursive_level > 0) {
    if (func_graph() != nullptr) {
      buffer << func_graph()->ToString() << ":";
    }
  }
  buffer << ToString();
  return buffer.str();
}

ParamInfoPtr Parameter::param_info() const {
  if (!has_default()) {
    return nullptr;
  }
  auto tensor = default_param()->cast<tensor::MetaTensorPtr>();
  if (tensor == nullptr || !tensor->is_parameter()) {
    return nullptr;
  }
  return tensor->param_info();
}

std::string ValueNode::ToString() const {
  MS_EXCEPTION_IF_NULL(value_);
  if (value_->isa<FuncGraph>()) {
    return value_->cast<FuncGraphPtr>()->ToString();
  }
  std::ostringstream buffer;
  buffer << AnfNode::ToString();
  buffer << "(" << value_->ToString() << ")";
  return buffer.str();
}

std::string ValueNode::DebugString(int) const {
  MS_EXCEPTION_IF_NULL(value_);
  std::ostringstream buffer;
  buffer << "ValueNode<" << value_->type_name() << "> " << value_->ToString();
  return buffer.str();
}

std::string ValueNode::fullname_with_scope() {
  if (!fullname_with_scope_.empty()) {
    return fullname_with_scope_;
  }

  MS_EXCEPTION_IF_NULL(scope());
  fullname_with_scope_ = scope()->name() + "/" + "data-" + id_generator::get_id(shared_from_base<ValueNode>());
  return fullname_with_scope_;
}

bool IsPrimitiveCNode(const AnfNodePtr &node, const PrimitivePtr &value) {
  MS_EXCEPTION_IF_NULL(node);
  auto cnode = node->cast<CNodePtr>();
  if (cnode == nullptr) {
    return false;
  }
  if (value != nullptr) {
    return cnode->IsApply(value);
  }
  const auto &prim = GetValueNode<PrimitivePtr>(cnode->input(0));
  return prim != nullptr;
}

PrimitivePtr GetCNodePrimitive(const AnfNodePtr &node) {
  if (node == nullptr) {
    return nullptr;
  }
  auto cnode = node->cast<CNodePtr>();
  if (cnode != nullptr) {
    if (cnode->size() > 0) {
      auto prim = GetValueNode<PrimitivePtr>(cnode->input(0));
      return prim;
    }
  }
  return nullptr;
}

std::string GetCNodeFuncName(const CNodePtr cnode) {
  if (cnode->inputs().empty()) {
    return "";
  }

  AnfNodePtr valuenode = cnode->input(0);
  if (valuenode->isa<ValueNode>()) {
    auto value = GetValueNode(valuenode);
    // check whether the valuenode is primitive
    if (value->isa<Primitive>()) {
      return value->cast<PrimitivePtr>()->name();
    }
    return value->ToString();
  }
  return "";
}

bool IsPrimitive(const AnfNodePtr &node, const PrimitivePtr &value) {
  if (IsValueNode<Primitive>(node)) {
    PrimitivePtr fn_value = GetValueNode<PrimitivePtr>(node);
    MS_EXCEPTION_IF_NULL(value);
    if (fn_value->Hash() == value->Hash() && fn_value->name() == value->name()) {
      return true;
    }
  }
  return false;
}

size_t NewSeenGeneration() {
  static size_t seen_generation = 0;
  return ++seen_generation;
}

namespace id_generator {
static std::unordered_map<std::string, int> node_ids;
std::string get_id(const AnfNodePtr &node) {
  auto type_name = node->type_name();
  if (node_ids.find(type_name) == node_ids.end()) {
    node_ids[type_name] = 0;
  } else {
    node_ids[type_name]++;
  }
  return std::to_string(node_ids[type_name]);
}

void reset_id() { node_ids.clear(); }
}  // namespace id_generator

namespace {
std::string GetMaketupleNodeTarget(const CNodePtr &cnode) {
  MS_EXCEPTION_IF_NULL(cnode);
  auto func_graph = cnode->func_graph();
  MS_EXCEPTION_IF_NULL(func_graph);
  auto manager = func_graph->manager();
  MS_EXCEPTION_IF_NULL(manager);
  auto users = manager->node_users()[cnode];
  std::string first_user_target = GetCNodeTarget(users.back().first);
  bool is_used_by_different_target =
    std::any_of(std::begin(users), std::end(users), [&first_user_target](const std::pair<AnfNodePtr, int> &u) -> bool {
      return GetCNodeTarget(u.first) != first_user_target;
    });
  if (!is_used_by_different_target) {
    return first_user_target;
  }

  auto inputs = cnode->inputs();
  std::vector<AnfNodePtr> real_inputs;
  std::copy(inputs.begin() + 1, inputs.end(), std::back_inserter(real_inputs));
  std::string first_input_target = GetCNodeTarget(real_inputs[0]);
  bool is_from_different_target =
    std::any_of(std::begin(real_inputs), std::end(real_inputs),
                [&first_input_target](const AnfNodePtr &n) -> bool { return GetCNodeTarget(n) != first_input_target; });
  if (!is_from_different_target) {
    return first_input_target;
  }

  auto context_ptr = MsContext::GetInstance();
  MS_EXCEPTION_IF_NULL(context_ptr);
  std::string default_target = context_ptr->get_param<std::string>(MS_CTX_DEVICE_TARGET);
  return default_target;
}

std::string GetTupleGetItemTarget(const CNodePtr &cnode, const PrimitivePtr &primitive) {
  MS_EXCEPTION_IF_NULL(cnode);
  MS_EXCEPTION_IF_NULL(primitive);
  auto input_target = GetCNodeTarget(cnode->input(1));
  primitive->set_attr("primitive_target", MakeValue(input_target));
  return input_target;
}
}  // namespace

std::string GetCNodeTarget(const AnfNodePtr &node) {
  auto context_ptr = MsContext::GetInstance();
  MS_EXCEPTION_IF_NULL(context_ptr);
  std::string default_target = context_ptr->get_param<std::string>(MS_CTX_DEVICE_TARGET);
  if (!node->isa<CNode>()) {
    return default_target;
  }
  auto cnode = node->cast<CNodePtr>();
  MS_EXCEPTION_IF_NULL(cnode);
  auto attr_input = cnode->input(0);
  if (attr_input == nullptr) {
    return default_target;
  }
  auto value_node = attr_input->cast<ValueNodePtr>();
  if (value_node == nullptr) {
    return default_target;
  }
  auto value = value_node->value();
  if (value == nullptr) {
    return default_target;
  }
  if (!value->isa<Primitive>()) {
    return default_target;
  }
  auto primitive = value->cast<PrimitivePtr>();
  auto att_target = primitive->GetAttr("primitive_target");
  if (att_target != nullptr) {
    if (IsPrimitive(attr_input, prim::kPrimImageSummary) || IsPrimitive(attr_input, prim::kPrimScalarSummary) ||
        IsPrimitive(attr_input, prim::kPrimTensorSummary) || IsPrimitive(attr_input, prim::kPrimHistogramSummary) ||
        IsPrimitive(attr_input, prim::kPrimStateSetItem) || IsPrimitive(attr_input, prim::kPrimDepend) ||
        IsPrimitive(attr_input, prim::kPrimControlDepend) || IsPrimitive(attr_input, prim::kPrimReturn) ||
        IsPrimitive(attr_input, prim::kPrimPartial)) {
      primitive->EraseAttr("primitive_target");
      return default_target;
    }
    if (!att_target->isa<StringImm>()) {
      MS_LOG(EXCEPTION) << "Only support string CPU|GPU|Ascend for primitive_target";
    }
    auto target = GetValue<std::string>(att_target);
    if (kTargetSet.find(target) == kTargetSet.end()) {
      MS_LOG(EXCEPTION) << "Only support string CPU|GPU|Ascend for primitive_target, but get " << target;
    }
    return target;
  }
  if (IsPrimitiveCNode(node, prim::kPrimMakeTuple)) {
    return GetMaketupleNodeTarget(cnode);
  }
  if (IsPrimitiveCNode(node, prim::kPrimTupleGetItem)) {
    return GetTupleGetItemTarget(cnode, primitive);
  }
  return default_target;
}
}  // namespace mindspore