public:

enum class progress { complete, input, output, eof, failed };

struct result {

progress state;

std::size_t bytes = 0;

http::outcome_code failure = http::outcome_code::protocol_error;

};

tls_session(std::shared_ptr<const tls_context> context, bool server, tls_handshake_context handshake = {});

tls_session(tls_credentials_selection selection, bool server, tls_handshake_context handshake = {});

~tls_session();

// Serialized pump access only. Null before success or after failed auth.

std::shared_ptr<const server::tls_peer_metadata> peer_metadata() const;

// Unknown until a successful authenticated handshake; owned protocol value.

tls_negotiated_protocol negotiated_protocol() const;

result handshake();

std::shared_ptr<tls_psk_runtime> handshake_runtime() const;

void handshake_limits(std::chrono::steady_clock::time_point deadline, std::stop_token cancellation);

result read(std::span<std::byte> buffer);

result write(std::span<const std::byte> bytes);

result shutdown();

std::size_t input_capacity() const;

bool feed(std::span<const std::byte> bytes);

std::size_t drain(std::span<std::byte> bytes);

bool output_pending() const;

private:

friend class tls_context;

struct impl;

std::unique_ptr<impl> impl_;