#include "example.yunq.h"

namespace {

const uint64_t header_size = 24;  // 4x uint32, 1x uint64

struct ExtPointer {
  uint32_t offset;
  uint32_t length;
}

void CheckHeader(const glcr::ByteBuffer& bytes) {
  // TODO: Check ident.
  // TODO: Parse core size.
  // TODO: Parse extension size.
  // TODO: Check CRC32
  // TODO: Parse options.
}

void WriteHeader(glcr::ByteBuffer& bytes, uint32_t core_size, uint32_t extension_size) {
  bytes.WriteAt<uint32_t>(0, 0xDEADBEEF);  // TODO: Chose a more unique ident sequence.
  bytes.WriteAt<uint32_t>(4, core_size);
  bytes.WriteAt<uint32_t>(8, extension_size);
  bytes.WriteAt<uint32_t>(12, 0); // TODO: Calculate CRC32.
  bytes.WriteAt<uint64_t>(16, 0); // TODO: Add options.
}

}  // namespace

void OpenFileRequest::ParseFromBytes(const glcr::ByteBuffer& bytes) {
  CheckHeader();

  auto path_pointer = bytes.At<ExtPointer>(header_size + (8 * 0));

  set_path(bytes.StringAt(path_pointer.offset, path_pointer.length));

  set_options(bytes.At<uint64_t>(header_size + (8 * 1)));

}

void OpenFileRequest::ParseFromBytes(const glcr::ByteBuffer& bytes, const glcr::CapBuffer& caps) {
  CheckHeader();

  auto path_pointer = bytes.At<ExtPointer>(header_size + (8 * 0));

  set_path(bytes.StringAt(path_pointer.offset, path_pointer.length));

  set_options(bytes.At<uint64_t>(header_size + (8 * 1)));

}

OpenFileRequest::SerializeToBytes(glcr::ByteBuffer& bytes) {

  uint32_t next_extension = header_size + 8 * 2;
  const uint32_t core_size = next_extension;

  ExtPointer path_ptr{
    .offset = next_extension,
    // FIXME: Check downcast of str length.
    .length = path().length(),
  };

  bytes.WriteStringAt(next_extension, path());
  next_extension += path_ptr.length;

  bytes.WriteAt<ExtPointer>(header_size + (8 * 0), path_ptr);

  bytes.WriteAt<uint64_t>(header_size + (8 * 1), options());

  // The next extension pointer is the length of the message. 
  WriteHeader(bytes, core_size, next_extension);
}

OpenFileRequest::SerializeToBytes(glcr::ByteBuffer& bytes, glcr::CapBuffer& caps) {

  uint32_t next_extension = header_size + 8 * 2;
  const uint32_t core_size = next_extension;
  uint64_t next_cap = 0;

  ExtPointer path_ptr{
    .offset = next_extension,
    // FIXME: Check downcast of str length.
    .length = path().length(),
  };

  bytes.WriteStringAt(next_extension, path());
  next_extension += path_ptr.length;

  bytes.WriteAt<ExtPointer>(header_size + (8 * 0), path_ptr);

  bytes.WriteAt<uint64_t>(header_size + (8 * 1), options());

  // The next extension pointer is the length of the message. 
  WriteHeader(bytes, core_size, next_extension);
}

void File::ParseFromBytes(const glcr::ByteBuffer& bytes) {
  CheckHeader();

  auto path_pointer = bytes.At<ExtPointer>(header_size + (8 * 0));

  set_path(bytes.StringAt(path_pointer.offset, path_pointer.length));

  set_attrs(bytes.At<uint64_t>(header_size + (8 * 1)));

  set_mem_cap(0);

}

void File::ParseFromBytes(const glcr::ByteBuffer& bytes, const glcr::CapBuffer& caps) {
  CheckHeader();

  auto path_pointer = bytes.At<ExtPointer>(header_size + (8 * 0));

  set_path(bytes.StringAt(path_pointer.offset, path_pointer.length));

  set_attrs(bytes.At<uint64_t>(header_size + (8 * 1)));

  uint64_t mem_cap_ptr = bytes.At<uint64_t>(header_size + (8 * 2));

  set_mem_cap(caps.at(mem_cap_ptr));

}

File::SerializeToBytes(glcr::ByteBuffer& bytes) {

  uint32_t next_extension = header_size + 8 * 3;
  const uint32_t core_size = next_extension;

  ExtPointer path_ptr{
    .offset = next_extension,
    // FIXME: Check downcast of str length.
    .length = path().length(),
  };

  bytes.WriteStringAt(next_extension, path());
  next_extension += path_ptr.length;

  bytes.WriteAt<ExtPointer>(header_size + (8 * 0), path_ptr);

  bytes.WriteAt<uint64_t>(header_size + (8 * 1), attrs());

  // FIXME: Warn or error on serialization

  // The next extension pointer is the length of the message. 
  WriteHeader(bytes, core_size, next_extension);
}

File::SerializeToBytes(glcr::ByteBuffer& bytes, glcr::CapBuffer& caps) {

  uint32_t next_extension = header_size + 8 * 3;
  const uint32_t core_size = next_extension;
  uint64_t next_cap = 0;

  ExtPointer path_ptr{
    .offset = next_extension,
    // FIXME: Check downcast of str length.
    .length = path().length(),
  };

  bytes.WriteStringAt(next_extension, path());
  next_extension += path_ptr.length;

  bytes.WriteAt<ExtPointer>(header_size + (8 * 0), path_ptr);

  bytes.WriteAt<uint64_t>(header_size + (8 * 1), attrs());

  caps.Write(next_cap, mem_cap());
  bytes.WriteAt<uint64_t>(header_size + (8 * 2), next_cap++);

  // The next extension pointer is the length of the message. 
  WriteHeader(bytes, core_size, next_extension);
}