/*!********************************************************************

 Audacity: A Digital Audio Editor

 @file MultipartData.cpp

 Dmitry Vedenko
 **********************************************************************/

#include "MultipartData.h"

#include <algorithm>
#include <cstdint>
#include <cstring>

#include "AudacityException.h"

namespace audacity
{
namespace network_manager
{
namespace
{
class ByteBufferPart final : public MultipartData::Part
{
public:
   ByteBufferPart(const void* data, size_t size)
   {
      mData.resize(size);
      std::memcpy(mData.data(), data, size);
   }

   int64_t GetSize() const override
   {
      return static_cast<int64_t>(mData.size());
   }

   size_t GetOffset() const override
   {
      return mOffset;
   }

   size_t Read(void* buffer, size_t maxBytes) override
   {
      const size_t availableBytes = mData.size() - mOffset;

      maxBytes = std::min(maxBytes, availableBytes);

      std::memcpy(buffer, mData.data() + mOffset, maxBytes);

      mOffset += maxBytes;

      return maxBytes;
   }

   bool Seek(int64_t offset, int origin) override
   {
      switch (origin)
      {
      case SEEK_SET:
         if (offset <= GetSize())
         {
            mOffset = offset;
            return true;
         }
         break;
      case SEEK_CUR:
      {
         const int64_t targetOffset = offset + mOffset;

         if (targetOffset >= 0 && targetOffset < GetSize())
         {
            mOffset = targetOffset;
            return true;
         }
      }
      break;
      case SEEK_END:
      {
         const int64_t targetOffset = GetSize() + offset;

         if (targetOffset >= 0 && targetOffset < GetSize())
         {
            mOffset = targetOffset;
            return true;
         }
      }
      break;
      default:
         break;
      }

      return false;
   }

private:
   std::vector<uint8_t> mData;
   size_t mOffset { 0 };
};

class FilePart final : public MultipartData::Part
{
public:
   explicit FilePart(const wxFileName& fileName)
       : mFileName(fileName)
   {
      if (!fileName.FileExists())
      {
         throw SimpleMessageBoxException(ExceptionType::BadUserAction,
            XO("Failed to open the file for upload: %s")
               .Format(fileName.GetFullPath()));
      }

      if (!mFile.Open(fileName.GetFullPath()))
      {
         throw SimpleMessageBoxException(
            ExceptionType::BadUserAction,
            XO("Failed to open the file for upload: %s")
               .Format(fileName.GetFullPath()));
      }
   }

   int64_t GetSize() const override
   {
      return static_cast<int64_t>(mFileName.GetSize().GetValue());
   }

   size_t GetOffset() const override
   {
      return static_cast<size_t>(mFile.Tell());
   }

   size_t Read(void* buffer, size_t maxBytes) override
   {
      const auto bytesRead = mFile.Read(buffer, maxBytes);

      if (bytesRead == wxInvalidOffset)
         return 0;

      return static_cast<size_t>(bytesRead);
   }

   bool Seek(int64_t offset, int origin = SEEK_SET) override
   {
      static constexpr wxSeekMode map[] = { wxFromStart, wxFromCurrent,
                                            wxFromEnd };

      if (origin < SEEK_SET || origin > SEEK_END)
         return false;

      return wxInvalidOffset != mFile.Seek(offset, map[origin]);
   }

private:
   wxFile mFile;
   wxFileName mFileName;
};
}

void MultipartData::Part::SetHeader(
   const std::string& headerName, const std::string& headerValue)
{
   mHeaders.setHeader(headerName, headerValue);
}

void MultipartData::Part::SetContentType(const std::string& mimeType)
{
   SetHeader(common_headers::ContentType, mimeType);
}

void MultipartData::Part::SetContentDisposition(const std::string& disposition)
{
   SetHeader(common_headers::ContentDisposition, disposition);
}

const HeadersList& MultipartData::Part::GetHeaders() const
{
   return mHeaders;
}

void MultipartData::Add(std::string_view name, std::string_view value)
{
   Add(name, {}, value.data(), value.length());
}

void MultipartData::Add(
   std::string_view name, std::string_view contentType, const void* value,
   size_t size)
{
   mParts.emplace_back(std::make_unique<ByteBufferPart>(value, size));

   mParts.back()->SetContentDisposition("form-data; name=\"" + std::string(name) + "\"");

   if (!contentType.empty())
      mParts.back()->SetContentType(std::string(contentType));
}

void MultipartData::AddFile(
   std::string_view name, std::string_view contentType,
   const wxFileName& fileName)
{
   mParts.emplace_back(std::make_unique<FilePart>(fileName));

   mParts.back()->SetContentDisposition(
      "form-data; name=\"" + std::string(name) + "\"; filename=\"" +
      fileName.GetFullName().ToUTF8().data() + "\"");

   if (!contentType.empty())
      mParts.back()->SetContentType(std::string(contentType));
}

size_t MultipartData::GetPartsCount() const
{
   return mParts.size();
}

MultipartData::Part* MultipartData::GetPart(size_t idx)
{
   if (idx < mParts.size())
      return mParts[idx].get();

   return nullptr;
}

const MultipartData::Part* MultipartData::GetPart(size_t idx) const
{
   if (idx < mParts.size())
      return mParts[idx].get();

   return nullptr;
}

bool MultipartData::IsEmpty() const
{
   return mParts.empty();
}

}
}