#include "library/common/http/header_utility.h"

#include "common/http/header_map_impl.h"

namespace Envoy {
namespace Http {
namespace Utility {

std::string convertToString(envoy_data s) {
  return std::string(reinterpret_cast<char*>(const_cast<uint8_t*>(s.bytes)), s.length);
}

RequestHeaderMapPtr toRequestHeaders(envoy_headers headers) {
  RequestHeaderMapPtr transformed_headers = RequestHeaderMapImpl::create();
  for (envoy_header_size_t i = 0; i < headers.length; i++) {
    transformed_headers->addCopy(LowerCaseString(convertToString(headers.headers[i].key)),
                                 convertToString(headers.headers[i].value));
  }
  // The C envoy_headers struct can be released now because the headers have been copied.
  release_envoy_headers(headers);
  return transformed_headers;
}

RequestTrailerMapPtr toRequestTrailers(envoy_headers trailers) {
  RequestTrailerMapPtr transformed_trailers = RequestTrailerMapImpl::create();
  for (envoy_header_size_t i = 0; i < trailers.length; i++) {
    transformed_trailers->addCopy(LowerCaseString(convertToString(trailers.headers[i].key)),
                                  convertToString(trailers.headers[i].value));
  }
  // The C envoy_headers struct can be released now because the headers have been copied.
  release_envoy_headers(trailers);
  return transformed_trailers;
}

envoy_headers toBridgeHeaders(const HeaderMap& header_map) {
  envoy_header* headers =
      static_cast<envoy_header*>(safe_malloc(sizeof(envoy_header) * header_map.size()));
  envoy_headers transformed_headers;
  transformed_headers.length = 0;
  transformed_headers.headers = headers;

  header_map.iterate([&transformed_headers](const HeaderEntry& header) -> HeaderMap::Iterate {
    const absl::string_view header_key = header.key().getStringView();
    const absl::string_view header_value = header.value().getStringView();

    envoy_data key =
        copy_envoy_data(header_key.size(), reinterpret_cast<const uint8_t*>(header_key.data()));
    envoy_data value =
        copy_envoy_data(header_value.size(), reinterpret_cast<const uint8_t*>(header_value.data()));

    transformed_headers.headers[transformed_headers.length] = {key, value};
    transformed_headers.length++;

    return HeaderMap::Iterate::Continue;
  });
  return transformed_headers;
}

} // namespace Utility
} // namespace Http
} // namespace Envoy