#include "peer_identity_grpc.h"

#include <string_view>

#include "absl/strings/match.h"
#include "peer_identity.h"
#include "g3/grpc_headers.h"

namespace milotic::authz {

grpc::Status ExtractPeerIdentityFromAuthContext(
    const grpc::AuthContext& context, PeerSpiffeIdentity& peer_identity) {
  if (!context.IsPeerAuthenticated()) {
    return grpc::Status(grpc::StatusCode::UNAUTHENTICATED,
                        "Peer is unauthenticated");
  }
  if (context.GetPeerIdentityPropertyName() != GRPC_X509_SAN_PROPERTY_NAME) {
    return grpc::Status(grpc::StatusCode::PERMISSION_DENIED,
                        "Peer identity isn't X.509 SAN");
  }
  for (const grpc::string_ref& val : context.GetPeerIdentity()) {
    std::string_view str(val.data(), val.size());
    // As per SPIFFE specification, SPIFFE schema and trust domain are case
    // insensitive.
    // https://github.com/spiffe/spiffe/blob/main/standards/SPIFFE-ID.md#24-spiffe-id-parsing
    if (absl::StartsWithIgnoreCase(str, "spiffe://")) {
      peer_identity.spiffe_id = str;
    } else if (absl::EndsWith(str, ".prod.google.com")) {
      // BMC peers are expected to have only one FQDN.
      peer_identity.fqdn = str;
    }
  }
  return grpc::Status::OK;
}

}  // namespace milotic::authz