/* Copyright (c) 2016 PaddlePaddle Authors. All Rights Reserved.

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 "paddle/fluid/framework/program_desc.h"

extern "C" {
#include <xxhash.h>
}

#include <algorithm>
#include "paddle/fluid/framework/feed_fetch_type.h"
#include "paddle/fluid/framework/version.h"

namespace paddle {
namespace framework {

BlockDesc *ProgramDesc::AppendBlock(const BlockDesc &parent) {
  auto *b = desc_.add_blocks();
  b->set_parent_idx(parent.ID());
  b->set_idx(desc_.blocks_size() - 1);
  blocks_.emplace_back(new BlockDesc(this, b));
  return blocks_.back().get();
}

void ProgramDesc::Flush() {
  for (auto &block : blocks_) {
    block->Flush();
  }
}

proto::ProgramDesc *ProgramDesc::Proto() {
  Flush();
  return &desc_;
}

proto::OpVersionMap *ProgramDesc::OpVersionMap() {
  return desc_.mutable_op_version_map();
}

int64_t ProgramDesc::Version() const { return desc_.version().version(); }

void ProgramDesc::SetVersion(const int64_t version) {
  desc_.mutable_version()->set_version(version);
}

ProgramDesc::ProgramDesc() {
  SetVersion(kCurProgramVersion);
  auto *block = desc_.mutable_blocks()->Add();
  block->set_idx(kRootBlockIndex);
  block->set_parent_idx(kNoneBlockIndex);
  blocks_.emplace_back(new BlockDesc(this, block));
}

ProgramDesc::ProgramDesc(const ProgramDesc &o) {
  desc_ = o.desc_;
  std::vector<framework::BlockDesc *> old_block_desc;
  for (int i = 0; i < desc_.blocks_size(); ++i) {
    auto *block = desc_.mutable_blocks(i);
    blocks_.emplace_back(new BlockDesc(*o.blocks_[i], block, this));
    // record all block desc's ptr from origin program
    old_block_desc.emplace_back(o.blocks_[i].get());
  }
  for (size_t block_id = 0; block_id < blocks_.size(); ++block_id) {
    auto all_ops = blocks_[block_id]->AllOps();
    for (size_t op_id = 0; op_id < all_ops.size(); ++op_id) {
      auto &op = all_ops[op_id];

      for (const std::string &attr_name : op->AttrNames()) {
        if (op->GetAttrType(attr_name) == proto::AttrType::BLOCK) {
          framework::BlockDesc *block_desc =
              PADDLE_GET_CONST(framework::BlockDesc *, op->GetAttr(attr_name));
          if (std::find(old_block_desc.begin(),
                        old_block_desc.end(),
                        block_desc) != old_block_desc.end()) {
            // The block is owned by the origin program. Just use id to get
            // the corresponding block.
            int sub_block_id =
                o.Block(block_id).Op(op_id)->GetBlockAttrId(attr_name);
            op->SetBlockAttr(attr_name, MutableBlock(sub_block_id));
          } else {
            // The block is not owned by the origin program. Should copy
            // the real block desc instead of logical block in the program.
            VLOG(3) << "Set op's block attr with the original block";
            op->SetBlockAttr(attr_name, block_desc);
          }
        } else if (op->GetAttrType(attr_name) == proto::AttrType::BLOCKS) {
          std::vector<int> sub_block_ids =
              o.Block(block_id).Op(op_id)->GetBlocksAttrIds(attr_name);
          std::vector<BlockDesc *> block_descs;
          for (int block_id : sub_block_ids) {
            block_descs.push_back(MutableBlock(block_id));
          }
          op->SetBlocksAttr(attr_name, block_descs);
        } else if (op->GetAttrType(attr_name, true) == proto::AttrType::VAR) {
          VarDesc *var_desc =
              PADDLE_GET_CONST(VarDesc *, op->GetAttr(attr_name, true));
          op->SetVarAttr(attr_name,
                         o.Block(block_id).FindVarRecursive(var_desc->Name()));
        } else if (op->GetAttrType(attr_name, true) == proto::AttrType::VARS) {
          std::vector<VarDesc *> vars_desc = PADDLE_GET_CONST(
              std::vector<VarDesc *>, op->GetAttr(attr_name, true));
          std::vector<VarDesc *> new_vars_desc;
          std::transform(
              vars_desc.begin(),
              vars_desc.end(),
              std::back_inserter(new_vars_desc),
              [&](VarDesc *var_desc) {
                return o.Block(block_id).FindVarRecursive(var_desc->Name());
              });
          op->SetVarsAttr(attr_name, new_vars_desc);
        }
      }
    }
  }
}

ProgramDesc::ProgramDesc(const proto::ProgramDesc &desc) {
  desc_ = desc;
  InitFromProto();
}

void ProgramDesc::CopyFrom(const proto::ProgramDesc &desc) {
  blocks_.clear();
  desc_ = desc;
  InitFromProto();
}

ProgramDesc::ProgramDesc(const std::string &binary_str) {
  PADDLE_ENFORCE_EQ(desc_.ParseFromString(binary_str),
                    true,
                    platform::errors::InvalidArgument(
                        "Failed to parse program_desc from binary string."));
  InitFromProto();
}

void ProgramDesc::InitFromProto() {
  for (auto &block_desc : *desc_.mutable_blocks()) {
    blocks_.emplace_back(new BlockDesc(this, &block_desc));
  }
  for (auto &block : blocks_) {
    for (auto *op : block->AllOps()) {
      for (const auto &attr : op->Proto()->attrs()) {
        if (attr.type() == proto::AttrType::VAR) {
          std::string var_name = attr.var_name();
          VLOG(3) << "InitFromProto: SetVarAttr " << attr.name() << " from "
                  << var_name;
          op->SetVarAttr(attr.name(), op->FindVarRecursive(var_name));
        } else if (attr.type() == proto::AttrType::VARS) {
          auto vars_name = attr.vars_name();
          std::vector<VarDesc *> vars_desc;
          for (auto &var_name : vars_name) {
            VLOG(3) << "InitFromProto: SetVarsAttr " << attr.name() << " from "
                    << var_name;
            vars_desc.emplace_back(op->FindVarRecursive(var_name));
          }
          op->SetVarsAttr(attr.name(), vars_desc);
        } else if (attr.type() == proto::AttrType::BLOCK) {
          size_t blk_idx = attr.block_idx();
          op->SetBlockAttr(attr.name(), this->MutableBlock(blk_idx));
        } else if (attr.type() == proto::AttrType::BLOCKS) {
          auto blks_idx = attr.blocks_idx();
          std::vector<BlockDesc *> block_descs;
          for (int blk_idx : blks_idx) {
            block_descs.push_back(this->MutableBlock(blk_idx));
          }
          op->SetBlocksAttr(attr.name(), block_descs);
        }
      }
    }
  }
}

const std::vector<std::string> ProgramDesc::GetFeedTargetNames() {
  auto &global_block = Block(0);
  // The order of feed_target_names must follow the index specified in `col`.
  // since feed operator's order doesn't necessary follow 'col'.
  std::vector<std::string> feed_target_names;
  for (auto *op : global_block.AllOps()) {
    if (op->Type() == kFeedOpType) {
      size_t col = PADDLE_GET_CONST(int, op->GetAttr("col"));
      if (col >= feed_target_names.size()) {
        feed_target_names.resize(col + 1);
      }
      feed_target_names[col] = op->Output("Out")[0];
    }
  }
  return feed_target_names;
}

const std::vector<std::string> ProgramDesc::GetFetchTargetNames() {
  auto &global_block = Block(0);
  // The order of fetch_target_names must follow the index specified in `col`.
  // since fetch operator's order doesn't necessary follow 'col'.
  std::vector<std::string> fetch_target_names;
  for (auto *op : global_block.AllOps()) {
    if (op->Type() == kFetchOpType) {
      size_t col = PADDLE_GET_CONST(int, op->GetAttr("col"));
      if (col >= fetch_target_names.size()) {
        fetch_target_names.resize(col + 1);
      }
      fetch_target_names[col] = op->Input("X")[0];
    }
  }
  return fetch_target_names;
}

void ProgramDesc::SetFeedHolderName(const std::string &feed_holder_name) {
  auto *global_block = MutableBlock(0);
  int index = 0;
  for (auto *op : global_block->AllOps()) {
    if (op->Type() == kFeedOpType) {
      // Unify the input's name of all feed_ops to feed_holder_name
      global_block->RemoveVar(op->Input("X")[0]);
      op->SetInput("X", {feed_holder_name});
      op->SetAttr("col", {index});
      op->CheckAttrs();
      index++;
    }
  }

  auto *feed_holder = global_block->Var(feed_holder_name);
  feed_holder->SetType(proto::VarType::FEED_MINIBATCH);
  feed_holder->SetPersistable(true);
}

void ProgramDesc::SetFetchHolderName(const std::string &fetch_holder_name) {
  auto *global_block = MutableBlock(0);
  int index = 0;
  for (auto *op : global_block->AllOps()) {
    if (op->Type() == kFetchOpType) {
      // Unify the output's name of all fetch_ops to fetch_holder_name
      global_block->RemoveVar(op->Output("Out")[0]);
      op->SetOutput("Out", {fetch_holder_name});
      op->SetAttr("col", {index});
      op->CheckAttrs();
      index++;
    }
  }

  auto *fetch_holder = global_block->Var(fetch_holder_name);
  fetch_holder->SetType(proto::VarType::FETCH_LIST);
  fetch_holder->SetPersistable(true);
}

std::string ProgramDesc::CachedHashString() {
  std::string serialize_str;
  if (cached_hash_str_.size() == 0 || NeedUpdate()) {
    Flush();
    desc_.SerializePartialToString(&serialize_str);
    // non-cryptographic is enough
    cached_hash_str_ =
        std::to_string(XXH64(serialize_str.c_str(), serialize_str.size(), 1));
  }
  return cached_hash_str_;
}

bool ProgramDesc::NeedUpdate() const {
  bool need = false;
  for (auto &block : blocks_) {
    if (block->NeedUpdate()) {
      need = true;
      break;
    }
  }
  return need;
}

}  // namespace framework
}  // namespace paddle
