/*  SPDX-License-Identifier: GPL-2.0-or-later */
/*!********************************************************************

  Audacity: A Digital Audio Editor

  DataUploader.cpp

  Dmitry Vedenko

**********************************************************************/

#include "DataUploader.h"

#include <variant>

#include <wx/file.h>

#include "CodeConversions.h"

#include "IResponse.h"
#include "NetworkManager.h"
#include "NetworkUtils.h"
#include "Request.h"

#include "RequestPayload.h"

#include "BasicUI.h"

using namespace audacity::network_manager;

namespace audacity::cloud::audiocom::sync
{
constexpr int RetriesCount { 3 };

using UploadData = std::variant<std::vector<uint8_t>, std::string>;

struct DataUploader::UploadOperation final :
    std::enable_shared_from_this<DataUploader::UploadOperation>
{
   DataUploader& Uploader;
   UploadUrls Target;
   std::function<void(ResponseResult)> Callback;
   std::function<void(double)> ProgressCallback;

   std::string MimeType;
   UploadData Data;

   ResponseResult CurrentResult;
   CancellationContextPtr CancelContext;

   std::atomic<bool> UploadFailed { false };

   UploadOperation(
      DataUploader& uploader, CancellationContextPtr cancellationContex,
      const UploadUrls& target, UploadData data, std::string mimeType,
      std::function<void(ResponseResult)> callback,
      std::function<void(double)> progressCallback)
       : Uploader { uploader }
       , Target { target }
       , Callback { std::move(callback) }
       , ProgressCallback { std::move(progressCallback) }
       , MimeType { std::move(mimeType) }
       , Data { std::move(data) }
       , CancelContext { std::move(cancellationContex) }
   {
   }

   void PerformUpload(int retriesLeft)
   {
      Request request { Target.UploadUrl };
      request.setHeader(common_headers::ContentType, MimeType);

      ResponsePtr networkResponse;

      if (std::holds_alternative<std::vector<uint8_t>>(Data))
      {
         auto data = *std::get_if<std::vector<uint8_t>>(&Data);

         networkResponse = NetworkManager::GetInstance().doPut(
            request, data.data(), data.size());
      }
      else
      {
         auto filePath = *std::get_if<std::string>(&Data);

         networkResponse = NetworkManager::GetInstance().doPut(
            request, CreateRequestPayloadStream(filePath));
      }

      CancelContext->OnCancelled(networkResponse);

      networkResponse->setRequestFinishedCallback(
         [this, retriesLeft, networkResponse, operation = weak_from_this()](auto)
         {
            auto strongThis = operation.lock();
            if (!strongThis)
               return;

            CurrentResult = GetResponseResult(*networkResponse, false);

            if (CurrentResult.Code == SyncResultCode::Success)
               ConfirmUpload(RetriesCount);
            else if (
               CurrentResult.Code == SyncResultCode::ConnectionFailed &&
               retriesLeft > 0)
               PerformUpload(retriesLeft - 1);
            else
               FailUpload(RetriesCount);
         });

      networkResponse->setUploadProgressCallback(
         [this, operation = weak_from_this()](
            int64_t current, int64_t total)
         {
            auto strongThis = operation.lock();
            if (!strongThis)
               return;

            if (total <= 0)
            {
               total   = 1;
               current = 0;
            }

            ProgressCallback(static_cast<double>(current) / total);
         });
   }

   void ConfirmUpload(int retriesLeft)
   {
      Data = {};
      Request request { Target.SuccessUrl };

      SetOptionalHeaders(request);

      auto networkResponse =
         NetworkManager::GetInstance().doPost(request, nullptr, 0);
      CancelContext->OnCancelled(networkResponse);

      networkResponse->setRequestFinishedCallback(
         [this, retriesLeft, networkResponse, operation = weak_from_this()](auto)
         {
            auto strongThis = operation.lock();
            if (!strongThis)
               return;

            CurrentResult = GetResponseResult(*networkResponse, false);

            if (CurrentResult.Code == SyncResultCode::Success)
            {
               Callback(ResponseResult { SyncResultCode::Success, {} });
               CleanUp();
            }
            else if (
               CurrentResult.Code == SyncResultCode::ConnectionFailed &&
               retriesLeft > 0)
            {
               ConfirmUpload(retriesLeft - 1);
            }
            else
            {
               FailUpload(RetriesCount);
            }
         });
   }

   void FailUpload(int retriesLeft)
   {
      if (!UploadFailed.exchange(true))
      {
         Data = {};
         Callback(CurrentResult);
      }

      Request request { Target.FailUrl };

      auto networkResponse =
         NetworkManager::GetInstance().doPost(request, nullptr, 0);
      CancelContext->OnCancelled(networkResponse);

      networkResponse->setRequestFinishedCallback(
         [this, retriesLeft, networkResponse, operation = weak_from_this()](auto)
         {
            auto strongThis = operation.lock();
            if (!strongThis)
               return;

            const auto result = GetResponseResult(*networkResponse, false);

            if (
               result.Code == SyncResultCode::ConnectionFailed &&
               retriesLeft > 0)
               FailUpload(retriesLeft - 1);
            else
               CleanUp();

            // Ignore other errors, server will collect garbage
            // and delete the file eventually
         });
   }

   void CleanUp()
   {
      BasicUI::CallAfter([this]() { Uploader.RemoveResponse(*this); });
   }
};

DataUploader::~DataUploader()
{
}

DataUploader& DataUploader::Get()
{
   static DataUploader instance;
   return instance;
}

void DataUploader::Upload(
   CancellationContextPtr cancellationContex, const ServiceConfig&,
   const UploadUrls& target, std::vector<uint8_t> data,
   std::function<void(ResponseResult)> callback,
   std::function<void(double)> progressCallback)
{
   if (!callback)
      callback = [](auto...) {};

   if (!progressCallback)
      progressCallback = [](auto...) { return true; };

   if (!cancellationContex)
      cancellationContex = concurrency::CancellationContext::Create();

   auto lock = std::lock_guard { mResponseMutex };

   mResponses.emplace_back(std::make_unique<UploadOperation>(
      *this, cancellationContex, target, std::move(data),
      audacity::network_manager::common_content_types::ApplicationXOctetStream,
      std::move(callback), std::move(progressCallback)));

   mResponses.back()->PerformUpload(RetriesCount);
}

void DataUploader::Upload(
   CancellationContextPtr cancellationContex, const ServiceConfig& config,
   const UploadUrls& target, std::string filePath,
   std::function<void(ResponseResult)> callback,
   std::function<void(double)> progressCallback)
{
   if (!callback)
      callback = [](auto...) {};

   if (!progressCallback)
      progressCallback = [](auto...) { return true; };

   if (!cancellationContex)
      cancellationContex = concurrency::CancellationContext::Create();

   if (!wxFileExists(audacity::ToWXString(filePath)))
   {
      if (callback)
         callback(ResponseResult {
            SyncResultCode::UnknownError,
            audacity::ToUTF8(XO("File not found").Translation()) });

      return;
   }

   auto lock = std::lock_guard { mResponseMutex };

   mResponses.emplace_back(std::make_shared<UploadOperation>(
      *this, cancellationContex, target, std::move(filePath),
      audacity::network_manager::common_content_types::ApplicationXOctetStream,
      std::move(callback), std::move(progressCallback)));

   mResponses.back()->PerformUpload(RetriesCount);
}

void DataUploader::RemoveResponse(UploadOperation& response)
{
   auto lock = std::lock_guard { mResponseMutex };

   mResponses.erase(
      std::remove_if(
         mResponses.begin(), mResponses.end(),
         [&response](const auto& item) { return item.get() == &response; }),
      mResponses.end());
}
} // namespace audacity::cloud::audiocom::sync