/* * Copyright (c)
 * 		2018 - present: Slavey Karadzhov <slav@attachix.com>
 * 		2014: Deoxxa Development (https://github.com/deoxxa/mqtt-protocol-c/)
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *  * Neither the name of Slavey Karadzhov and Deoxxa Development nor the names
 * of its contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef MQTT_PARSER_H
#define MQTT_PARSER_H

#include <stddef.h>
#include <stdint.h>

#include "platform.h"
#include "errors.h"
#include "message.h"

#ifdef __cplusplus
extern "C" {
#endif

typedef enum mqtt_parser_rc_e {
  MQTT_PARSER_RC_INCOMPLETE = 0,
  MQTT_PARSER_RC_ERROR,
  MQTT_PARSER_RC_CONTINUE,
  MQTT_PARSER_RC_DONE,
  MQTT_PARSER_RC_WANT_MEMORY,
} mqtt_parser_rc_t;

typedef enum mqtt_parser_state_e {
  MQTT_PARSER_STATE_INITIAL,
  MQTT_PARSER_STATE_REMAINING_LENGTH,
  MQTT_PARSER_STATE_REMAINING_LENGTH_DONE,
  MQTT_PARSER_STATE_VARIABLE_HEADER,
#if MQTT_ENABLE_SERVER
  // Client to server
  MQTT_PARSER_STATE_CONNECT,
  MQTT_PARSER_STATE_CONNECT_PROTOCOL_NAME,
  MQTT_PARSER_STATE_CONNECT_PROTOCOL_VERSION,
  MQTT_PARSER_STATE_CONNECT_FLAGS,
  MQTT_PARSER_STATE_CONNECT_KEEP_ALIVE,
  MQTT_PARSER_STATE_CONNECT_CLIENT_IDENTIFIER,
  MQTT_PARSER_STATE_CONNECT_WILL_TOPIC,
  MQTT_PARSER_STATE_CONNECT_WILL_MESSAGE,
  MQTT_PARSER_STATE_CONNECT_USERNAME,
  MQTT_PARSER_STATE_CONNECT_PASSWORD,
  MQTT_PARSER_STATE_SUBSCRIBE,
  MQTT_PARSER_STATE_SUBSCRIBE_TOPICS,
  MQTT_PARSER_STATE_SUBSCRIBE_TOPIC_NAME,
  MQTT_PARSER_STATE_SUBSCRIBE_TOPIC_QOS,
  MQTT_PARSER_STATE_UNSUBSCRIBE,
  MQTT_PARSER_STATE_UNSUBSCRIBE_TOPICS,
  MQTT_PARSER_STATE_UNSUBSCRIBE_TOPIC_NAME,
  MQTT_PARSER_STATE_PINGREQ,
  MQTT_PARSER_STATE_DISCONNECT,
#endif /* MQTT_ENABLE_SERVER */
#if MQTT_ENABLE_CLIENT
  // Server to client
  MQTT_PARSER_STATE_CONNACK,
  MQTT_PARSER_STATE_SUBACK,
  MQTT_PARSER_STATE_SUBACK_QOS,
  MQTT_PARSER_STATE_UNSUBACK,
  MQTT_PARSER_STATE_PINGRESP,
#endif /* MQTT_ENABLE_CLIENT */

  // Bi-directional
  MQTT_PARSER_STATE_PUBLISH,
  MQTT_PARSER_STATE_PUBLISH_TOPIC_NAME,
  MQTT_PARSER_STATE_PUBLISH_MESSAGE_ID,
  MQTT_PARSER_STATE_PUBLISH_PAYLOAD,
  MQTT_PARSER_STATE_PUBLISH_PAYLOAD_READ,
  MQTT_PARSER_STATE_PUBACK,
  MQTT_PARSER_STATE_PUBREC,
  MQTT_PARSER_STATE_PUBREL,
  MQTT_PARSER_STATE_PUBCOMP,

  MQTT_PARSER_STATE_DONE,
} mqtt_parser_state_t;

typedef struct {
  /* In the message the correct type and expected length will be set. */
  int (*on_message_begin)(void*, mqtt_message_t*);

  /* If the message is PUBLISH the following data methods will be called */
  int (*on_data_begin)(void*, mqtt_message_t*);
  int (*on_data_payload)(void*, mqtt_message_t*, const char*, size_t);
  int (*on_data_end)(void*, mqtt_message_t*);

  /* The complete message will be delivered. If PUBLISH the payload will not be
     * set by default. */
  int (*on_message_end)(void*, mqtt_message_t*);

} mqtt_parser_callbacks_t;

#define MQTT_PARSER_STATE_READ_STRING (1 << 7)

typedef struct mqtt_parser_s {
  const mqtt_parser_callbacks_t* callbacks;

  mqtt_parser_state_t state;
  mqtt_error_t error;

  size_t needs; /* bytes needed to read the full content of a package */
  size_t string_length;
  size_t nread;      /* bytes read */
  uint8_t stored[2]; /* stored characters */
  uint8_t flags;     /*
                         Order: First bit is the on the right, Last bit is on the
                         left.     7 - set if a string is started to be read     6-2 -
                         unused     1-0 - the last two bits are used to specify the number
                         of     stored bytes
                         */

  char buffer_pending;
  uint8_t* buffer;
  size_t buffer_length;

  /** PUBLIC **/
  void* data; /* A pointer to get hook to the "connection" or "socket" object */

} mqtt_parser_t;

void mqtt_parser_init(mqtt_parser_t* parser, mqtt_parser_callbacks_t* callbacks);
void mqtt_parser_buffer(mqtt_parser_t* parser, uint8_t* buffer, size_t buffer_length);
mqtt_parser_rc_t mqtt_parser_execute(mqtt_parser_t* parser, mqtt_message_t* message, uint8_t* data, size_t len);

#ifdef __cplusplus
}
#endif

#endif