//
// Copyright Aliaksei Levin (levlam@telegram.org), Arseny Smirnov (arseny30@gmail.com) 2014-2018
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
#include "td/telegram/files/FileLoadManager.h"

#include "td/telegram/Global.h"

#include "td/utils/common.h"
#include "td/utils/filesystem.h"
#include "td/utils/logging.h"

namespace td {
FileLoadManager::FileLoadManager(ActorShared<Callback> callback, ActorShared<> parent)
    : callback_(std::move(callback)), parent_(std::move(parent)) {
}

void FileLoadManager::start_up() {
  upload_resource_manager_ =
      create_actor<ResourceManager>("UploadResourceManager", !G()->parameters().use_file_db /*tdlib_engine*/
                                                                 ? ResourceManager::Mode::Greedy
                                                                 : ResourceManager::Mode::Baseline);
  download_resource_manager_ =
      create_actor<ResourceManager>("DownloadResourceManager", ResourceManager::Mode::Baseline);
  download_small_resource_manager_ =
      create_actor<ResourceManager>("DownloadSmallResourceManager", ResourceManager::Mode::Baseline);
}

void FileLoadManager::download(QueryId id, const FullRemoteFileLocation &remote_location,
                               const LocalFileLocation &local, int64 size, string name,
                               const FileEncryptionKey &encryption_key, int priority) {
  if (stop_flag_) {
    return;
  }
  CHECK(query_id_to_node_id_.find(id) == query_id_to_node_id_.end());
  NodeId node_id = nodes_container_.create(Node());
  Node *node = nodes_container_.get(node_id);
  CHECK(node);
  node->query_id_ = id;
  auto callback = make_unique<FileDownloaderCallback>(actor_shared(this, node_id));
  bool is_small = size < 20 * 1024;
  node->loader_ = create_actor<FileDownloader>("Downloader", remote_location, local, size, std::move(name),
                                               encryption_key, is_small, std::move(callback));
  auto &resource_manager = is_small ? download_small_resource_manager_ : download_resource_manager_;
  send_closure(resource_manager, &ResourceManager::register_worker,
               ActorShared<FileLoaderActor>(node->loader_.get(), static_cast<uint64>(-1)), priority);
  query_id_to_node_id_[id] = node_id;
}

void FileLoadManager::upload(QueryId id, const LocalFileLocation &local_location,
                             const RemoteFileLocation &remote_location, int64 size,
                             const FileEncryptionKey &encryption_key, int priority, vector<int> bad_parts) {
  if (stop_flag_) {
    return;
  }
  CHECK(query_id_to_node_id_.find(id) == query_id_to_node_id_.end());
  NodeId node_id = nodes_container_.create(Node());
  Node *node = nodes_container_.get(node_id);
  CHECK(node);
  node->query_id_ = id;
  auto callback = make_unique<FileUploaderCallback>(actor_shared(this, node_id));
  node->loader_ = create_actor<FileUploader>("Uploader", local_location, remote_location, size, encryption_key,
                                             std::move(bad_parts), std::move(callback));
  send_closure(upload_resource_manager_, &ResourceManager::register_worker,
               ActorShared<FileLoaderActor>(node->loader_.get(), static_cast<uint64>(-1)), priority);
  query_id_to_node_id_[id] = node_id;
}

void FileLoadManager::upload_by_hash(QueryId id, const FullLocalFileLocation &local_location, int64 size,
                                     int priority) {
  if (stop_flag_) {
    return;
  }
  CHECK(query_id_to_node_id_.find(id) == query_id_to_node_id_.end());
  NodeId node_id = nodes_container_.create(Node());
  Node *node = nodes_container_.get(node_id);
  CHECK(node);
  node->query_id_ = id;
  auto callback = make_unique<FileHashUploaderCallback>(actor_shared(this, node_id));
  node->loader_ = create_actor<FileHashUploader>("HashUploader", local_location, size, std::move(callback));
  send_closure(upload_resource_manager_, &ResourceManager::register_worker,
               ActorShared<FileLoaderActor>(node->loader_.get(), static_cast<uint64>(-1)), priority);
  query_id_to_node_id_[id] = node_id;
}

void FileLoadManager::update_priority(QueryId id, int priority) {
  if (stop_flag_) {
    return;
  }
  auto it = query_id_to_node_id_.find(id);
  if (it == query_id_to_node_id_.end()) {
    return;
  }
  auto node = nodes_container_.get(it->second);
  if (node == nullptr) {
    return;
  }
  send_closure(node->loader_, &FileLoaderActor::update_priority, priority);
}

void FileLoadManager::from_bytes(QueryId id, FileType type, BufferSlice bytes, string name) {
  if (stop_flag_) {
    return;
  }
  CHECK(query_id_to_node_id_.find(id) == query_id_to_node_id_.end());
  NodeId node_id = nodes_container_.create(Node());
  Node *node = nodes_container_.get(node_id);
  CHECK(node);
  node->query_id_ = id;
  auto callback = make_unique<FileFromBytesCallback>(actor_shared(this, node_id));
  node->loader_ =
      create_actor<FileFromBytes>("FromBytes", type, std::move(bytes), std::move(name), std::move(callback));
  query_id_to_node_id_[id] = node_id;
}

void FileLoadManager::get_content(const FullLocalFileLocation &local_location, Promise<BufferSlice> promise) {
  // TODO: send query to other thread
  promise.set_result(read_file(local_location.path_));
}

// void upload_reload_parts(QueryId id, vector<int32> parts);
// void upload_restart(QueryId id);
void FileLoadManager::cancel(QueryId id) {
  if (stop_flag_) {
    return;
  }
  auto it = query_id_to_node_id_.find(id);
  if (it == query_id_to_node_id_.end()) {
    return;
  }
  on_error_impl(it->second, Status::Error(1, "Cancelled"));
}
void FileLoadManager::update_local_file_location(QueryId id, const LocalFileLocation &local) {
  if (stop_flag_) {
    return;
  }
  auto it = query_id_to_node_id_.find(id);
  if (it == query_id_to_node_id_.end()) {
    return;
  }
  auto node = nodes_container_.get(it->second);
  if (node == nullptr) {
    return;
  }
  send_closure(node->loader_, &FileLoaderActor::update_local_file_location, local);
}
void FileLoadManager::close() {
  nodes_container_.for_each([](auto id, auto &node) { node.loader_.reset(); });
  stop_flag_ = true;
  loop();
}

void FileLoadManager::on_start_download() {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_start_download, node->query_id_);
  }
}

void FileLoadManager::on_partial_download(const PartialLocalFileLocation &partial_local, int64 ready_size) {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_partial_download, node->query_id_, partial_local, ready_size);
  }
}

void FileLoadManager::on_partial_upload(const PartialRemoteFileLocation &partial_remote, int64 ready_size) {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_partial_upload, node->query_id_, partial_remote, ready_size);
  }
}

void FileLoadManager::on_ok_download(const FullLocalFileLocation &local, int64 size) {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_download_ok, node->query_id_, local, size);
  }
  close_node(node_id);
  loop();
}

void FileLoadManager::on_ok_upload(FileType file_type, const PartialRemoteFileLocation &remote, int64 size) {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_upload_ok, node->query_id_, file_type, remote, size);
  }
  close_node(node_id);
  loop();
}

void FileLoadManager::on_ok_upload_full(const FullRemoteFileLocation &remote) {
  auto node_id = get_link_token();
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_upload_full_ok, node->query_id_, remote);
  }
  close_node(node_id);
  loop();
}

void FileLoadManager::on_error(Status status) {
  auto node_id = get_link_token();
  on_error_impl(node_id, std::move(status));
}

void FileLoadManager::on_error_impl(NodeId node_id, Status status) {
  auto node = nodes_container_.get(node_id);
  if (node == nullptr) {
    status.ignore();
    return;
  }
  if (!stop_flag_) {
    send_closure(callback_, &Callback::on_error, node->query_id_, std::move(status));
  }
  close_node(node_id);
  loop();
}

void FileLoadManager::hangup_shared() {
  auto node_id = get_link_token();
  on_error_impl(node_id, Status::Error(1, "Cancelled"));
}

void FileLoadManager::loop() {
  if (stop_flag_) {
    if (nodes_container_.empty()) {
      stop();
    }
    return;
  }
}

void FileLoadManager::close_node(NodeId node_id) {
  auto node = nodes_container_.get(node_id);
  CHECK(node);
  query_id_to_node_id_.erase(node->query_id_);
  nodes_container_.erase(node_id);
}

}  // namespace td