/*
 * Copyright (c) 2016, Yasuyuki Tanaka
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the copyright holder 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 HOLDER 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.
 */
/**
 * \addtogroup sixtop
 * @{
 */
/**
 * \file
 *         Transaction Management APIs for 6top Protocol (6P)
 * \author
 *         Yasuyuki Tanaka <yasuyuki.tanaka@inf.ethz.ch>
 */

#include "sixp.h"
#include "sixp-pkt.h"

/**
 * \brief 6P Transaction States (for internal use)
 */
typedef enum {
  SIXP_TRANS_STATE_UNAVAILABLE = 0,
  SIXP_TRANS_STATE_INIT,
  SIXP_TRANS_STATE_REQUEST_SENT,
  SIXP_TRANS_STATE_REQUEST_RECEIVED,
  SIXP_TRANS_STATE_RESPONSE_SENT,
  SIXP_TRANS_STATE_RESPONSE_RECEIVED,
  SIXP_TRANS_STATE_CONFIRMATION_SENT,
  SIXP_TRANS_STATE_CONFIRMATION_RECEIVED,
  SIXP_TRANS_STATE_TERMINATING,
} sixp_trans_state_t;

/**
 * \brief 6P Transaction Modes (for internal use)
 */
typedef enum {
  SIXP_TRANS_MODE_UNAVAILABLE = 0,
  SIXP_TRANS_MODE_2_STEP,
  SIXP_TRANS_MODE_3_STEP
} sixp_trans_mode_t;

typedef struct sixp_trans sixp_trans_t;

/**
 * \brief Change the state of a specified transaction
 * \param trans The pointer to a transaction
 * \param new_state New state to move the transaction to
 * \return 0 on success, -1 on failure
 */
int sixp_trans_transit_state(sixp_trans_t *trans,
                             sixp_trans_state_t new_state);

/**
 * \brief Return the command associated with a specified transaction
 * \param trans The pointer to  a transaction
 * \return Command identifier; SIXP_PKT_CMD_UNAVAILABLE on failure
 */
sixp_pkt_cmd_t sixp_trans_get_cmd(sixp_trans_t *trans);

/**
 * \brief Return the state of a specified transaction
 * \param trans The pointer to a transaction
 * \return a state of the transaction; SIXP_TRANS_STATE_UNAVAILABLE if the
 * transaction is not found in the system.
 */
sixp_trans_state_t sixp_trans_get_state(sixp_trans_t *trans);

/**
 * \brief Return the sequence number associated with a specified transaction
 * \param trans The pointer of a transaction
 * \return 0 or larger than 0 on success, -1 on failure
 */
int16_t sixp_trans_get_seqno(sixp_trans_t *trans);

/**
 * \brief Return the mode, 2-step or 3-step, of a specified transaction
 * \param trans The pointer to a transaction
 * \return The mode of the transaction, SIXP_TRANS_MODE_UNAVAILABLE on failure
 */
sixp_trans_mode_t sixp_trans_get_mode(sixp_trans_t *trans);

/**
 * \brief Invoke the output callback of a specified transaction
 * \param trans The pointer to a transaction
 * \param status An output result value
 */
void sixp_trans_invoke_callback(sixp_trans_t *trans,
                                sixp_output_status_t status);

/**
 * \brief Set an output callback to a specified transaction
 * \param trans The pointer to a transaction
 * \param func The pointer to a callback function
 * \param arg The pointer to an argument which will be passed to func
 * \param arg_len The length of the argument
 */
void sixp_trans_set_callback(sixp_trans_t *trans,
                             sixp_sent_callback_t func,
                             void *arg,
                             uint16_t arg_len);

/**
 * \brief Allocate a transaction
 * \param pkt The pointer to a packet which triggers the allocation
 * \param peer_addr The peer address which will be associated
 * \return A pointer to an newly allocated transaction, NULL on failure
 */
sixp_trans_t *sixp_trans_alloc(const sixp_pkt_t *pkt,
                               const linkaddr_t *peer_addr);

/**
 * \brief Find a transaction
 * \param peer_addr The peer address
 * \return The pointer to a transaction; NULL on failure
 */
sixp_trans_t *sixp_trans_find(const linkaddr_t *peer_addr);

/**
 * \brief Initialize Memory and List for 6P transactions
 * This function removes and frees existing transactions.
 */
int sixp_trans_init(void);

/*---------------------------------------------------------------------------*/
/** @} */