WebsocketFrame.h

/*
 * WebsocketFrame.h
 *
 *  Created on: 13 nov. 2016 г.
 *  Author: https://github.com/avr39-ripe - Alexander V, Ribchansky
 *
 *  Some parts of code inspired by: https://github.com/Links2004/arduinoWebSockets and
 *  https://github.com/m8rge/cwebsocket
 */

#ifndef SMINGCORE_NETWORK_WEBSOCKETFRAME_H_
#define SMINGCORE_NETWORK_WEBSOCKETFRAME_H_
#include "../Wiring/WiringFrameworkIncludes.h"

enum class WSFrameType : uint8_t
{
    continuation = 0x00, // continuation frame, UNSUPPORTED BY NOW!
    text = 0x01,        // text frame
    binary = 0x02,      // binary frame
                                                        // %x3-7 are reserved for further non-control frames
    close = 0x08,       // connection close frame
    ping = 0x09,        // ping frame
    pong = 0x0A,        // pong frame
    empty = 0xF0,       // Empty frame, length == 0. Not from RFC6455! For internal class usage!
    error = 0xF1,       // Error while farsing frame. Not from RFC6455! For internal class usage!
    incomplete = 0xF2   // Incomplete, inconsistent frame. Not from RFC6455! For internal class usage!
};

namespace WSFlags
{
    static const uint8_t payloadDeleteMemBit = 1u; //Delete memory reserved for payload in destructor
    static const uint8_t headerDeleteMemBit = 2u; //Delete memory reserved for header in destructor
};

// Declare classes where WebsocketFrameClass can be used they will have access to _payload and _header members
class HttpServer;
class Websocket;
class WebsocketClient;

class WebsocketFrameClass
{
    friend class HttpServer;
    friend class Websocket;
    friend class WebsocketClient;
public:
    WebsocketFrameClass() {};
    virtual ~WebsocketFrameClass();
    uint8_t encodeFrame(WSFrameType frameType, uint8_t * payload, size_t length, uint8_t mask, uint8_t fin,  uint8_t headerToPayload = true);
    uint8_t decodeFrame(uint8_t * buffer, size_t length);
protected:
    uint8_t* _payload = nullptr; // pointer to payload; in encode - will point to proper websocket frame payload, in decode - will point to websocket frame's decoded data
    size_t _payloadLength = 0;
    uint8_t* _header = nullptr; // pointer to header; in encode - will point to websocket frame header
    size_t _headerLength = 0;
    WSFrameType _frameType = WSFrameType::empty;
    uint8_t _mask = 0;
    uint8_t _getFrameSizes(uint8_t* buffer, size_t length); // used to get frame size from websocket buffer
private:
    uint8_t _flags = 0; //Store flags for further freeing memory
    size_t _nextReadOffset = 0; //Store offset in multiframe tcp buffer for next decodeFrame
};
#endif /* SMINGCORE_NETWORK_WEBSOCKETFRAME_H_ */